URL
https://opencores.org/ocsvn/openrisc/openrisc/trunk
Subversion Repositories openrisc
[/] [openrisc/] [trunk/] [rtos/] [ecos-3.0/] [packages/] [devs/] [usb/] [sa11x0/] [current/] [src/] [usbs_sa11x0.c] - Rev 786
Compare with Previous | Blame | View Log
//========================================================================== // // usbs_sa11x0.c // // Device driver for the SA11x0 USB port. // //========================================================================== // ####ECOSGPLCOPYRIGHTBEGIN#### // ------------------------------------------- // This file is part of eCos, the Embedded Configurable Operating System. // Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc. // // eCos is free software; you can redistribute it and/or modify it under // the terms of the GNU General Public License as published by the Free // Software Foundation; either version 2 or (at your option) any later // version. // // eCos is distributed in the hope that it will be useful, but WITHOUT // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License // for more details. // // You should have received a copy of the GNU General Public License // along with eCos; if not, write to the Free Software Foundation, Inc., // 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. // // As a special exception, if other files instantiate templates or use // macros or inline functions from this file, or you compile this file // and link it with other works to produce a work based on this file, // this file does not by itself cause the resulting work to be covered by // the GNU General Public License. However the source code for this file // must still be made available in accordance with section (3) of the GNU // General Public License v2. // // This exception does not invalidate any other reasons why a work based // on this file might be covered by the GNU General Public License. // ------------------------------------------- // ####ECOSGPLCOPYRIGHTEND#### //========================================================================== //#####DESCRIPTIONBEGIN#### // // Author(s): bartv // Contributors: bartv // Date: 2000-10-04 // // This code implements support for the on-chip USB port on the SA11x0 // family of processors. The code has been developed on the SA1110 and // may or may not work on other members of the SA11x0 family. There // have problems with the USB support on certain revisions of the silicon, // so the errata sheet appropriate to the specific processor being used // should be consulted. There also appear to be problems which do not // appear on any errata, which this code attempts to work around. // //####DESCRIPTIONEND#### //========================================================================== #include <cyg/infra/cyg_type.h> #include <cyg/infra/cyg_ass.h> #include <cyg/infra/cyg_trac.h> #include <cyg/infra/diag.h> #include <pkgconf/hal_arm.h> #include <pkgconf/devs_usb_sa11x0.h> #include <cyg/hal/drv_api.h> #include <cyg/hal/hal_arch.h> #include <cyg/hal/hal_io.h> #include <cyg/hal/hal_cache.h> #include <cyg/hal/hal_sa11x0.h> #include <cyg/error/codes.h> #include <cyg/io/usb/usb.h> #include <cyg/io/usb/usbs.h> // Debugging support. By default this driver operates mostly at // DSR level, with the ISR doing a minimal amount of processing. // However is also possible to run most of the code at thread-level, // This is subject to some restrictions because the USB standard // imposes timing constraints, e.g. some control operations such // as SET-ADDRESS have to complete within 50ms. However it is // very useful for debugging, specifically it allows you to put // printf()'s in various places. // // Right now these configuration options are not exported to the // user because running at DSR level is likely to be good enough // for everybody not actively debugging this code. The options // could be exported if necessary. //#define CYGPKG_DEVS_USB_SA11X0_THREAD #undef CYGPKG_DEVS_USB_SA11X0_THREAD #ifdef CYGPKG_DEVS_USB_SA11X0_THREAD // Default stack size should be CYGNUM_HAL_STACK_SIZE_TYPICAL # define CYGNUM_DEVS_USB_SA11X0_THREAD_STACK_SIZE 4096 # define CYGNUM_DEVS_USB_SA11X0_THREAD_PRIORITY 7 # include <cyg/kernel/kapi.h> #endif #if 0 # define DBG(a) diag_printf a #else # define DBG(a) #endif #undef FAILURES #ifdef FAILURES static volatile int ep1_failure = 7; #endif #undef STATS #ifdef STATS int ep1_receives = 0; int ep1_errors = 0; int ep2_transmits = 0; int ep2_errors = 0; # define INCR_STAT(a) (a) += 1 # define SET_STAT(a, b) (a) = (b) #else # define INCR_STAT(a) # define SET_STAT(a, b) #endif // ---------------------------------------------------------------------------- // Serial port 0 on the SA11x0 provides a USB slave connection (aka a // USB device controller or UDC). The functionality is somewhat // limited, there are just three endpoints. // // Endpoint 0 can only be used for control messages. It has an 8 byte // fifo which cannot be connected to a DMA engine. Hence incoming // control packets have to be limited to 8 bytes by the enumeration // data. The endpoint has to be managed at a low-level, i.e. the // incoming request has to be extracted from the fifo, processed, and // any response put back into the fifo within the permitted USB // response times. // // Endpoint 1 can only be used for host->slave bulk OUT transfers. It // has a 20 byte receive fifo, and it can be hooked up to any of the // six DMA engines. Since bulk transfers will typically involve 64 // byte packets, most applications will require the use of DMA. // // Endpoint 2 can only be used for slave-host bulk IN transfers. There // is a 16 byte transmit fifo so small messages can be transferred in // software. The fifo can also be hooked up to DMA, which is a more // likely scenario. // // Start with definitions of the hardware. The use of a structure and // a const base pointer should allow the compiler to do base/offset // addressing and keep the hardware base address in a register. This // is better than defining each hardware register via a separate // address. Although the registers are only a byte wide, the peripheral // bus only supports word accesses. // // The USBS_CONTROL etc. macros allow for an alternative way of // accessing the hardware if a better approach is presented, without // having to rewrite all the code. Macros that correspond to registers // are actually addresses, making it easier in the code to distinguish // them from bit values: the & and * operators will just cancel out. typedef struct usbs_sa11x0_hardware { volatile int control; volatile int address; volatile int out_size; volatile int in_size; volatile int ep0_control; volatile int ep1_control; volatile int ep2_control; volatile int ep0_data; volatile int ep0_write_count; int dummy1; volatile int fifo; int dummy2; volatile int status; } usbs_sa11x0_hardware; static usbs_sa11x0_hardware* const usbs_sa11x0_base = (usbs_sa11x0_hardware* const) 0x80000000; #define USBS_CONTROL (&(usbs_sa11x0_base->control)) #define USBS_ADDRESS (&(usbs_sa11x0_base->address)) #define USBS_OUT_SIZE (&(usbs_sa11x0_base->out_size)) #define USBS_IN_SIZE (&(usbs_sa11x0_base->in_size)) #define EP0_CONTROL (&(usbs_sa11x0_base->ep0_control)) #define EP1_CONTROL (&(usbs_sa11x0_base->ep1_control)) #define EP2_CONTROL (&(usbs_sa11x0_base->ep2_control)) #define EP0_DATA (&(usbs_sa11x0_base->ep0_data)) #define EP0_WRITE_COUNT (&(usbs_sa11x0_base->ep0_write_count)) #define EP1_DATA (&(usbs_sa11x0_base->fifo)) #define EP2_DATA (&(usbs_sa11x0_base->fifo)) #define USBS_STATUS (&(usbs_sa11x0_base->status)) #define CONTROL_DISABLE (1 << 0) #define CONTROL_ACTIVE (1 << 1) // The meaning of bit 2 changed, see errata #define CONTROL_RESUME_INTR (1 << 2) #define CONTROL_EP0_INTR (1 << 3) #define CONTROL_EP1_INTR (1 << 4) #define CONTROL_EP2_INTR (1 << 5) // The meaning of bit 6 also changed, see errata #define CONTROL_SUSPEND_INTR (1 << 6) #define CONTROL_RESET_INTR (1 << 7) // Getting the control register settings right is a little bit tricky. // Bit 0 is the disable bit so touching that is dangerous, and the // other bits have inverted meanings i.e. 0 enables interrupts. The // following macro encapsulates this. #define CONTROL_ALL_INTR 0x00FC #define CONTROL_INTR_ENABLE(bits) ((~(bits)) & CONTROL_ALL_INTR) #define CONTROL_INTR_CLEAR(bits) ((bits) & CONTROL_ALL_INTR) // All the endpoint interrupt numbers can be handled en masse, // but some of the endpoints may be disabled. #if defined(CYGPKG_DEVS_USB_SA11X0_EP1) && defined(CYGPKG_DEVS_USB_SA11X0_EP2) # define CONTROL_EP_INTR_BITS (CONTROL_EP0_INTR | CONTROL_EP1_INTR | CONTROL_EP2_INTR) #elif defined(CYGPKG_DEVS_USB_SA11X0_EP1) # define CONTROL_EP_INTR_BITS (CONTROL_EP0_INTR | CONTROL_EP1_INTR) #elif defined(CYGPKG_DEVS_USB_SA11X0_EP2) # define CONTROL_EP_INTR_BITS (CONTROL_EP0_INTR | CONTROL_EP2_INTR) #else # define CONTROL_EP_INTR_BITS (CONTROL_EP0_INTR) #endif #define EP0_OUT_READY (1 << 0) #define EP0_IN_READY (1 << 1) #define EP0_SENT_STALL (1 << 2) #define EP0_FORCE_STALL (1 << 3) #define EP0_DATA_END (1 << 4) #define EP0_SETUP_END (1 << 5) #define EP0_SERVICED_OPR (1 << 6) #define EP0_SERVICED_SETUP_END (1 << 7) #define EP1_FIFO_SERVICE (1 << 0) #define EP1_PACKET_COMPLETE (1 << 1) #define EP1_PACKET_ERROR (1 << 2) #define EP1_SENT_STALL (1 << 3) #define EP1_FORCE_STALL (1 << 4) #define EP1_FIFO_NOT_EMPTY (1 << 5) #define EP2_FIFO_SERVICE (1 << 0) #define EP2_PACKET_COMPLETE (1 << 1) #define EP2_PACKET_ERROR (1 << 2) #define EP2_PACKET_UNDERRUN (1 << 3) #define EP2_SENT_STALL (1 << 4) #define EP2_FORCE_STALL (1 << 5) #define STATUS_EP0_INTR (1 << 0) #define STATUS_EP1_INTR (1 << 1) #define STATUS_EP2_INTR (1 << 2) #define STATUS_SUSPEND_INTR (1 << 3) #define STATUS_RESUME_INTR (1 << 4) #define STATUS_RESET_INTR (1 << 5) #define EP0_FIFO_SIZE 8 #define EP0_MTU 8 #define EP1_FIFO_SIZE 20 #ifdef CYGNUM_DEVS_USB_SA11X0_EP1_DMA_CHANNEL # define EP1_MTU 64 #else # define EP1_MTU 16 #endif #define EP2_FIFO_SIZE 16 #ifdef CYGNUM_DEVS_USB_SA11X0_EP2_DMA_CHANNEL # define EP2_MTU 64 #else # define EP2_MTU 16 #endif #if defined(CYGNUM_DEVS_USB_SA11X0_EP1_DMA_CHANNEL) || defined(CYGNUM_DEVS_USB_SA11X0_EP2_DMA_CHANNEL) typedef struct usbs_sa11x0_dma { volatile int address; volatile int control_set; volatile int control_clear; volatile int status; volatile int buf_a_address; // Absolute, not remapped volatile int buf_a_size; volatile int buf_b_address; // Absolute, not remapped volatile int buf_b_size; } usbs_sa11x0_dma; #define DMA_CONTROL_RUN (1 << 0) #define DMA_CONTROL_INTR_ENABLE (1 << 1) #define DMA_STATUS_ERROR (1 << 2) #define DMA_STATUS_DONE_A (1 << 3) #define DMA_CONTROL_START_A (1 << 4) #define DMA_STATUS_DONE_B (1 << 5) #define DMA_CONTROL_START_B (1 << 6) #define DMA_STATUS_BUFFER_IN_USE (1 << 7) // All the bits that are useful to clear. BUFFER_IN_USE is read-only. #define DMA_CONTROL_CLEAR_ALL (DMA_CONTROL_RUN | DMA_CONTROL_INTR_ENABLE | DMA_STATUS_ERROR | \ DMA_STATUS_DONE_A | DMA_CONTROL_START_A | DMA_STATUS_DONE_B | DMA_CONTROL_START_B) // The DMA engines operate eight-bytes at a time. This affects issues // such as alignment. #define DMA_BURST_SIZE 8 // The DMA engines bypass the cache and MMU, accessing physical // memory directly. Newer HALS should provide appropriate macros. #ifndef HAL_VIRT_TO_PHYS_ADDRESS # error HAL macros for translating between virtual and physical memory are required. #endif // Make absolutely sure that the two endpoints use different // DMA channels. Right now this check cannot be done easily // at the CDL level. # if defined(CYGNUM_DEVS_USB_SA11X0_EP1_DMA_CHANNEL) && defined(CYGNUM_DEVS_USB_SA11X0_EP2_DMA_CHANNEL) # if (CYGNUM_DEVS_USB_SA11X0_EP1_DMA_CHANNEL == CYGNUM_DEVS_USB_SA11X0_EP2_DMA_CHANNEL) # error Different DMA channels must be selected for the two endpoints. # endif # endif # ifdef CYGNUM_DEVS_USB_SA11X0_EP1_DMA_CHANNEL static usbs_sa11x0_dma* const ep1_dma_base = (usbs_sa11x0_dma* const)(0xB0000000 | (0x20 * CYGNUM_DEVS_USB_SA11X0_EP1_DMA_CHANNEL)); # define EP1_DMA_ADDRESS (&(ep1_dma_base->address)) # define EP1_DMA_CONTROL_SET (&(ep1_dma_base->control_set)) # define EP1_DMA_CONTROL_CLEAR (&(ep1_dma_base->control_clear)) # define EP1_DMA_STATUS (&(ep1_dma_base->status)) # define EP1_DMA_BUF_A_ADDRESS (&(ep1_dma_base->buf_a_address)) # define EP1_DMA_BUF_A_SIZE (&(ep1_dma_base->buf_a_size)) # define EP1_DMA_BUF_B_ADDRESS (&(ep1_dma_base->buf_b_address)) # define EP1_DMA_BUF_B_SIZE (&(ep1_dma_base->buf_b_size)) // The correct value for the DMA address register is fixed for USB transfers // See table 11.6 of the SA1110 Advanced Developer's Manual // Device datum width == 1 byte // Device burst size == 8 bytes // Device transfer direction == read (device->memory) // Endianness is controlled by the ARM architectural HAL package # ifdef CYGHWR_HAL_ARM_BIGENDIAN # define EP1_DMA_ADDRESS_VALUE (0x80000A00 | 0x10 | 0x0 | 0x4 | 0x2 | 0x1) # else # define EP1_DMA_ADDRESS_VALUE (0x80000A00 | 0x10 | 0x0 | 0x4 | 0x0 | 0x1) # endif # endif // EP1_DMA # ifdef CYGNUM_DEVS_USB_SA11X0_EP2_DMA_CHANNEL static usbs_sa11x0_dma* const ep2_dma_base = (usbs_sa11x0_dma* const)(0xB0000000 | (0x20 * CYGNUM_DEVS_USB_SA11X0_EP2_DMA_CHANNEL)); # define EP2_DMA_ADDRESS (&(ep2_dma_base->address)) # define EP2_DMA_CONTROL_SET (&(ep2_dma_base->control_set)) # define EP2_DMA_CONTROL_CLEAR (&(ep2_dma_base->control_clear)) # define EP2_DMA_STATUS (&(ep2_dma_base->status)) # define EP2_DMA_BUF_A_ADDRESS (&(ep2_dma_base->buf_a_address)) # define EP2_DMA_BUF_A_SIZE (&(ep2_dma_base->buf_a_size)) # define EP2_DMA_BUF_B_ADDRESS (&(ep2_dma_base->buf_b_address)) # define EP2_DMA_BUF_B_SIZE (&(ep2_dma_base->buf_b_size)) # ifdef CYGHWR_HAL_ARM_BIGENDIAN # define EP2_DMA_ADDRESS_VALUE (0x80000A00 | 0x00 | 0x0 | 0x4 | 0x2 | 0x0) # else # define EP2_DMA_ADDRESS_VALUE (0x80000A00 | 0x00 | 0x0 | 0x4 | 0x0 | 0x0) # endif # endif // EP2_DMA #endif // EP1_DMA || EP2_DMA // ---------------------------------------------------------------------------- // Static data. There is a data structure for each endpoint. The // implementation is essentially a private class that inherits from // common classes for control and data endpoints, but device drivers // are supposed to be written in C so some ugliness is required. // // Devtab entries are defined in usbs_sa11x0_data.cxx to make sure // that the linker does not garbage-collect them. // Support for the interrupt handling code. static cyg_interrupt usbs_sa11x0_intr_data; static cyg_handle_t usbs_sa11x0_intr_handle; static volatile int isr_status_bits = 0; // Endpoint 0 is always present, this module would not get compiled // otherwise. static void usbs_sa11x0_ep0_start(usbs_control_endpoint*); static void usbs_sa11x0_poll(usbs_control_endpoint*); typedef enum ep0_state { EP0_STATE_IDLE = 0, EP0_STATE_IN = 1, EP0_STATE_OUT = 2 } ep0_state; typedef struct ep0_impl { usbs_control_endpoint common; ep0_state ep_state; int length; int transmitted; } ep0_impl; static ep0_impl ep0 = { common: { state: USBS_STATE_POWERED, // The hardware does not distinguish between detached, attached and powered. enumeration_data: (usbs_enumeration_data*) 0, start_fn: &usbs_sa11x0_ep0_start, poll_fn: &usbs_sa11x0_poll, interrupt_vector: SA11X0_IRQ_USB_SERVICE_REQUEST, control_buffer: { 0, 0, 0, 0, 0, 0, 0, 0 }, state_change_fn: (void (*)(usbs_control_endpoint*, void*, usbs_state_change, int)) 0, state_change_data: (void*) 0, standard_control_fn: (usbs_control_return (*)(usbs_control_endpoint*, void*)) 0, standard_control_data: (void*) 0, class_control_fn: (usbs_control_return (*)(usbs_control_endpoint*, void*)) 0, class_control_data: (void*) 0, vendor_control_fn: (usbs_control_return (*)(usbs_control_endpoint*, void*)) 0, vendor_control_data: (void*) 0, reserved_control_fn: (usbs_control_return (*)(usbs_control_endpoint*, void*)) 0, reserved_control_data: (void*) 0, buffer: (unsigned char*) 0, buffer_size: 0, fill_buffer_fn: (void (*)(usbs_control_endpoint*)) 0, fill_data: (void*) 0, fill_index: 0, complete_fn: (usbs_control_return (*)(usbs_control_endpoint*, int)) 0 }, ep_state: EP0_STATE_IDLE, length: 0, transmitted: 0 }; extern usbs_control_endpoint usbs_sa11x0_ep0 __attribute__((alias ("ep0"))); // Endpoint 1 is optional. If the application only involves control // messages or only slave->host transfers then the endpoint 1 // support can be disabled. #ifdef CYGPKG_DEVS_USB_SA11X0_EP1 typedef struct ep1_impl { usbs_rx_endpoint common; int fetched; cyg_bool using_buf_a; } ep1_impl; static void ep1_start_rx(usbs_rx_endpoint*); static void ep1_set_halted(usbs_rx_endpoint*, cyg_bool); static ep1_impl ep1 = { common: { start_rx_fn: &ep1_start_rx, set_halted_fn: &ep1_set_halted, complete_fn: (void (*)(void*, int)) 0, complete_data: (void*) 0, buffer: (unsigned char*) 0, buffer_size: 0, halted: 0, }, fetched: 0, using_buf_a: 0 }; extern usbs_rx_endpoint usbs_sa11x0_ep1 __attribute__((alias ("ep1"))); #endif // Endpoint 2 is optional. If the application only involves control // messages or only host->slave transfers then the endpoint 2 support // can be disabled. #ifdef CYGPKG_DEVS_USB_SA11X0_EP2 typedef struct ep2_impl { usbs_tx_endpoint common; int transmitted; int pkt_size; } ep2_impl; static void ep2_start_tx(usbs_tx_endpoint*); static void ep2_set_halted(usbs_tx_endpoint*, cyg_bool); static ep2_impl ep2 = { common: { start_tx_fn: &ep2_start_tx, set_halted_fn: &ep2_set_halted, complete_fn: (void (*)(void*, int)) 0, complete_data: (void*) 0, buffer: (const unsigned char*) 0, buffer_size: 0, halted: 0, }, transmitted: 0, pkt_size: 0 }; extern usbs_tx_endpoint usbs_sa11x0_ep2 __attribute__ ((alias ("ep2"))); #endif // ---------------------------------------------------------------------------- // Hardware problem: experiments indicate that manipulating the USB // controller registers does not always work as expected. The control // fifo is especially badly affected, with e.g. writes just being lost // completely. It is necessary to work around these problems using // retry loops. MAX_RETRIES controls the total number of attempts to // access a register. MAX_CHECKS controls the number of times a // register is checked to determine whether or not the attempt has // been succesful. These constants are used to access the data fifo, // so MAX_RETRIES has to be > 20 bytes. #define MAX_RETRIES 32 #define MAX_CHECKS 8 // Write one or more bits to a register. This should result in some // bits ending up set and other bits ending up clear. Some register // bits are write-1-to-clear or may have side effects. static cyg_bool usbs_sa11x0_poke(volatile int* addr, int value, int should_be_set, int should_be_clear) { cyg_bool result = false; int retries, checks; for (retries = 0; !result && (retries < MAX_RETRIES); retries++) { *addr = value; (void) *addr; // The first read is always invalid. for (checks = 0; !result && (checks < MAX_CHECKS); checks++) { int current_value = *addr; if (should_be_set != (should_be_set & current_value)) { continue; } if ((0 != should_be_clear) && (0 != (should_be_clear & current_value))) { continue; } result = true; } } if (!result) { DBG(("usbs_sa11x0_poke failed: addr %x, value %x, should_be_set %x, should_be_clear %x, actual %x\n", \ (int) addr, value, should_be_set, should_be_clear, *addr)); } return result; } // Write a whole value to a register, rather than just manipulating // individual bits. static cyg_bool usbs_sa11x0_poke_value(volatile int* addr, int value) { cyg_bool result = false; int retries, checks; for (retries = 0; !result && (retries < MAX_RETRIES); retries++) { *addr = value; (void) *addr; // The first read is always invalid. for (checks = 0; !result && (checks < MAX_CHECKS); checks++) { if (value == *addr) { result = true; } } } if (!result) { DBG(("usbs_sa11x0_poke_value failed: addr %x, value %x, actual %x\n", (int) addr, value, *addr)); } return result; } // ---------------------------------------------------------------------------- // Control transfers // // Endpoint 0 is rather more complicated than the others. This is // partly due to the nature of the control protocol, for example it is // bidirectional and transfer sizes are unpredictable. // // The USB standard imposes some timing constraints on endpoint 0, see // section 9.2.6 of the spec. For example the set-address operation is // supposed to take at most 50ms. In general the timings are reasonably // generous so no special action is taken here. There could be problems // when debugging, but that is pretty much inevitable. // // It is necessary to maintain a state for the control endpoint, the // default state being idle. Control operations involve roughly the // following sequence of events: // // 1) the host transmits a special setup token, indicating the start // of a control operation and possibly cancelling any existing control // operation that may be in progress. USB peripherals cannot NAK this // even if they are busy. // // 2) the setup operation is followed by an eight-byte packet from the host // that describes the specific control operation. This fits into the // SA11X0's eight-byte control fifo. There will be an endpoint 0 // interrupt with the out-packet-ready bit set. If the setup token // was sent while a previous control operation was also in progress // then the setup-end bit will be set as well. // // 3) the eight-byte packet is described in section 9.3 of the USB spec. // The first byte holds three fields, with the top bit indicating the // direction of subsequent data transfer. There are also two bytes // specifying the size of the subsequent transfer. Obviously the // packet also contains information such as the request type. // // If the specified size is zero then the endpoint will remain in // its idle state. Otherwise the endpoint will switch to either // IN or OUT state, depending on the direction of subsequent // transfers. // // 4) some standard control operations can be handled by the code // here. Set-address involves poking the address register and // a change of state. Set-feature and clear-feature on the // data endpoints can be used in conjunction with endpoint-halt. // Get-status on the data endpoints tests the halt condition. // It is also possible for the hardware-specific code to // implement set-feature, clear-feature and get-status // for the device as a whole since the SA11x0 always has to // be self-powered and is incapable of initiating a remote // wakeup. // // Other standard control operations will be handled by the // application-specific installed handler, if any, or by the // default handler usbs_handle_standard_control(). Class-specific // and vendor-specific functions require appropriate handlers to be // installed as well, If a particular request is not recognized // then a stall condition should be raised. This will not prevent // subsequent control operations, just the current one. // // Data transfers on endpoint 0 involve at most eight bytes at // a time. More data will only be accepted if the out-packet-ready // bit has been cleared via the serviced-opr bit, with the // hardware nak'ing OUT requests. To send data back to the host // the FIFO should be filled and then the in-packet-ready bit // should be set. // // It looks like processing all control packets at DSR level should be // sufficient. During the data phase the hardware will NAK IN and // OUT requests if the fifo is still empty/full, so timing is not // an issue. Timing after receipt of the initial control message // may be more important, e.g. the 50ms upper limit on processing // the set-address control message, but this should still be ok. // This decision may have to be re-examined in the light of // experience. // Init may get called during system startup or following a reset. // During startup no work is needed since the hardware will // have been reset and everything should be fine. After a reset // the hardware will also be ok but there may be state information // in ep0 that needs to be reset. static void usbs_sa11x0_ep0_init(void) { if ((EP0_STATE_IDLE != ep0.ep_state) && ((usbs_control_return (*)(usbs_control_endpoint*, int)) 0 != ep0.common.complete_fn)) { (*ep0.common.complete_fn)(&ep0.common, -EPIPE); } ep0.common.state = USBS_STATE_POWERED; memset(ep0.common.control_buffer, 0, 8); ep0.common.buffer = (unsigned char*) 0; ep0.common.buffer_size = 0; ep0.common.fill_buffer_fn = (void (*)(usbs_control_endpoint*)) 0; ep0.common.fill_data = (void*) 0; ep0.common.fill_index = 0; ep0.common.complete_fn = (usbs_control_return (*)(usbs_control_endpoint*, int)) 0; ep0.ep_state = EP0_STATE_IDLE; ep0.length = 0; ep0.transmitted = 0; } // The start function is called by higher-level code when things have // been set up, i.e. the enumeration data is available, appropriate // handlers have been installed for the different types of control // messages, and communication with the host is allowed to start. The // next event that should happen is a reset operation from the host, // so all other interrupts should be blocked. However it is likely // that the hardware will detect a suspend state before the reset // arrives, and hence the reset will act as a resume as well as a // reset. static void usbs_sa11x0_ep0_start(usbs_control_endpoint* endpoint) { CYG_ASSERT( endpoint == &ep0.common, "USB startup involves the wrong endpoint"); // Activate the hardware. Write a 0 to the enable/disable bit 0. // Bit 1 is read-only. The other bits are set to 1 to disable // the corresponding interrupt source. usbs_sa11x0_poke(USBS_CONTROL, CONTROL_ALL_INTR, CONTROL_ALL_INTR, 0); // If there is additional platform-specific initialization to // perform, do it now. This macro can come from the platform HAL. #ifdef SA11X0_USB_PLATFORM_INIT SA11X0_USB_PLATFORM_INIT; #endif // Clear any pending interrupts. There should not be any, but just // in case. Note: passing 0x00FF as the should_be_clear argument // is a race condition, an external event can happen at any time, // so we may loop unnecessarily and lose an interrupt. However // the initial reset should last for 10ms. usbs_sa11x0_poke(USBS_STATUS, 0x00FF, 0x00, 0x00FF); // The only interrupt really of interest right now is reset, but // it is likely to be preceded by a resume. usbs_sa11x0_poke(USBS_CONTROL, CONTROL_INTR_ENABLE(CONTROL_RESET_INTR | CONTROL_RESUME_INTR), 0, CONTROL_INTR_CLEAR(CONTROL_RESET_INTR | CONTROL_RESUME_INTR)); } // Filling the fifo with a reply to the host. This can be called // immediately at the end of a control message, to prepare for // the next IN token. It will also get called after each subsequent // IN operation when the fifo has been emptied. // // Experiments have indicated serious problems with the control fifo: // some writes to the fifo just get lost completely. The failure rate // is sufficiently high that more often than not the host will be // unable to read all the enumeration data. However, the write-count // register appears to give a valid indication of the current fifo // contents. This means the code can retry stuffing a particular byte // into the fifo until the write-count goes up. static void usbs_sa11x0_ep0_fill_fifo(void) { cyg_bool ok = true; int filled = 0; int max; int fifo_count = *EP0_WRITE_COUNT; int bits_to_set = 0; // The host can interrupt the current control message at any time // with a new one. In practice this is unlikely, things could get // rather confused on the host side. However if a control message // has been received then the fifo should obviously not be filled. // A new control message is indicated by the SETUP_END bit. // // The hardware design means that there is a race condition: the // new control message can come in at any time, even in the middle // of filling the fifo. Checking the SETUP_END more often would // reduce the probability of things getting messed up, but not // eliminate it. // // There is a check for SETUP_END at the start of the DSR, so // the setting of this bit should have resulted in another ISR // and another DSR being scheduled. Hence there is no need for // special action here. if (0 != (*EP0_CONTROL & EP0_SETUP_END)) { DBG(("EP0_fill_fifo(), interrupted by SETUP_END\n")); return; } // There should never be any data in the fifo. Any such data could // be the remnant of a previous transfer to the host, but that // should all have gone out already. Alternatively it could be // incoming data, but that means a new control message. if (0 != fifo_count) { DBG(("EP0_fill_fifo(), fifo already contains %d bytes", fifo_count)); return; } // The IN_READY bit should never be set on entry. It can only get // set by a previous call to fill_fifo(), and the data should // have gone out before we get back here. if (0 != (*EP0_CONTROL & EP0_IN_READY)) { DBG(("EP0 fill_fifo(), in-packet-ready bit already set, state %x\n", *EP0_CONTROL)); return; } // Now put up to another eight bytes into the fifo. max = ((ep0.length - ep0.transmitted) > EP0_FIFO_SIZE) ? EP0_FIFO_SIZE : (ep0.length - ep0.transmitted); while (ok && (filled < max)) { if (0 != ep0.common.buffer_size) { int datum; int retries, checks; cyg_bool written; datum = *ep0.common.buffer++; ep0.common.buffer_size--; written = false; for (retries = 0; ok && !written && (retries < MAX_RETRIES); retries++) { if (filled != *EP0_WRITE_COUNT) { DBG(("EP0 fill_fifo, inconsistency, written %d but write count %d\n", filled, *EP0_WRITE_COUNT)); ok = false; } *EP0_DATA = datum; // The write-count may take a few cycles to settle down. for (checks = 0; !written && (checks < MAX_CHECKS); checks++) { if (filled < *EP0_WRITE_COUNT) { filled++; written = true; // DBG(("Transferred %d byte (%x) after %d checks, %d retries\n", filled - 1, datum, checks, retries)); } } } } else if ((void (*)(usbs_control_endpoint*))0 != ep0.common.fill_buffer_fn) { (*ep0.common.fill_buffer_fn)(&ep0.common); } else { break; } } // At this point either it has proved impossible to fill the fifo, // e.g. because of a new control message, or up to another eight // bytes have been sent. if (!ok) { if (0 == (EP0_SETUP_END & *EP0_CONTROL)) { // There is something seriously wrong. DBG(("ep0_fill_fifo(), failed, only filled %d bytes, status %x\n", filled, *EP0_CONTROL)); usbs_sa11x0_poke(EP0_CONTROL, EP0_FORCE_STALL, EP0_FORCE_STALL, 0); } return; } // The following conditions are possible: // 1) amount transferred == amount requested, transfer complete. // 2) amount transferred < amount requested, this fill involved // <eight bytes, transfer complete by definition of the protocol. // 3) amount transferred < amount requested but exactly eight // bytes were sent this time. It will be necessary to send // another packet of zero bytes to complete the transfer. ep0.transmitted += filled; if ((ep0.transmitted == ep0.length) || (filled < EP0_FIFO_SIZE)) { ep0.ep_state = EP0_STATE_IDLE; if ((usbs_control_return (*)(usbs_control_endpoint*, int))0 != ep0.common.complete_fn) { (void) (*ep0.common.complete_fn)(&ep0.common, 0); } ep0.common.buffer = (unsigned char*) 0; ep0.common.buffer_size = 0; ep0.common.fill_buffer_fn = (void (*)(usbs_control_endpoint*)) 0; // This informs the hardware that the control message has been // handled. bits_to_set = EP0_DATA_END; } // This allows another IN operation to empty the fifo. bits_to_set |= EP0_IN_READY; usbs_sa11x0_poke(EP0_CONTROL, bits_to_set, bits_to_set, 0); } // Another utility function to empty the fifo. This involves similar // hardware problems to writing, it is possible to read a byte without // changing the fifo state so that next time the same byte would be // read again. Again there is a possible race condition if another // control message arrives while emptying the fifo. static int usbs_sa11x0_ep0_empty_fifo(unsigned char* buf) { int count = *EP0_WRITE_COUNT & 0x00FF; int emptied = 0; cyg_bool ok = true; CYG_ASSERT( (count >= 0) & (count <= 8), "EP0 write count must be in range"); while (ok && (emptied < count)) { int retries, checks; cyg_bool read = false; for (retries = 0; !read && (retries < MAX_RETRIES); retries++) { if ((count - emptied) != *EP0_WRITE_COUNT) { DBG(("EP0_empty_fifo, inconsistency, read %d bytes of %d, but fifo count %d\n", emptied, count, *EP0_WRITE_COUNT)); ok = false; } else { buf[emptied] = *EP0_DATA; for (checks = 0; !read && (checks < MAX_CHECKS); checks++) { if ((count - emptied) > *EP0_WRITE_COUNT) { //DBG(("Read %d byte (%x) after %d checks, %d retries\n", emptied, buf[emptied], checks, retries)); read = true; emptied++; } } } } if (ok && !read) { DBG(("EP0 empty fifo, failed to read byte from fifo\n")); ok = false; } } return emptied; } // This is where all the hard work happens. It is a very large routine // for a DSR, but in practice nearly all of it is nested if's and very // little code actually gets executed. Note that there may be // invocations of callback functions and the driver has no control // over how much time those will take, but those callbacks should be // simple. static void usbs_sa11x0_ep0_dsr(void) { int hw_state = *EP0_CONTROL; // Handle the stall bits. // // Force-stall should not be a problem. It is set by the code here // if the host needs to be told that the control message was // unacceptable and is cleared automatically by the hardware after // the stall is sent. // NOTE: it is not clear the hardware actually works in this // respect. The FORCE_STALL bit has been observed still set during // the next interrupt, and the host appears to receive spurious // data back in response to the next control packet. // // Sent-stall is set by the hardware following a protocol // violation, e.g. if there is an IN token when a new control // message is expected. There is nothing the software can do about // this. However if we are in the middle of an IN or OUT transfer // then those are not going to complete successfully. if (0 != (hw_state & EP0_SENT_STALL)) { if (EP0_STATE_IDLE != ep0.ep_state) { if ((usbs_control_return (*)(usbs_control_endpoint*, int))0 != ep0.common.complete_fn) { (*ep0.common.complete_fn)(&ep0.common, -EIO); } ep0.ep_state = EP0_STATE_IDLE; ep0.common.buffer = (unsigned char*) 0; ep0.common.buffer_size = 0; ep0.common.fill_buffer_fn = 0; ep0.common.complete_fn = (usbs_control_return (*)(usbs_control_endpoint*, int)) 0; } usbs_sa11x0_poke(EP0_CONTROL, EP0_SENT_STALL, 0, EP0_SENT_STALL); } // STALL condition // Next, check whether we have received a new control message // while still busy processing an old one. if (0 != (hw_state & EP0_SETUP_END)) { if (EP0_STATE_IDLE != ep0.ep_state) { if ((usbs_control_return (*)(usbs_control_endpoint*, int)) 0 != ep0.common.complete_fn) { (*ep0.common.complete_fn)(&ep0.common, -EIO); } ep0.ep_state = EP0_STATE_IDLE; ep0.common.buffer = (unsigned char*) 0; ep0.common.buffer_size = 0; ep0.common.fill_buffer_fn = 0; ep0.common.complete_fn = (usbs_control_return (*)(usbs_control_endpoint*, int)) 0; } // We are now back in idle state so the control message will be // extracted and processed. usbs_sa11x0_poke(EP0_CONTROL, EP0_SERVICED_SETUP_END, 0, EP0_SETUP_END); } // Interrupted control transaction // The endpoint can be in one of three states: IN, OUT, or IDLE. // For the first two it should mean that there is more data to be // transferred, which is pretty straightforward. IDLE means // that a new control message has arrived. if ((EP0_STATE_IN == ep0.ep_state) && (0 == (EP0_IN_READY & hw_state))) { usbs_sa11x0_ep0_fill_fifo(); } else if ((EP0_STATE_OUT == ep0.ep_state) && (0 != (EP0_OUT_READY & hw_state))) { // A host->device transfer. Higher level code must have // provided a suitable buffer. CYG_ASSERT( (unsigned char*)0 != ep0.common.buffer, "A receive buffer should have been provided" ); ep0.transmitted += usbs_sa11x0_ep0_empty_fifo(ep0.common.buffer + ep0.transmitted); if (ep0.transmitted != ep0.length) { // The host is not allowed to send more data than it // indicated in the original control message, and all // messages until the last one should be full size. CYG_ASSERT( ep0.transmitted < ep0.length, "The host must not send more data than expected"); CYG_ASSERT( 0 == (ep0.transmitted % EP0_FIFO_SIZE), "All OUT packets until the last one should be full-size"); usbs_sa11x0_poke(EP0_CONTROL, EP0_SERVICED_OPR, 0, EP0_OUT_READY); } else { // The whole transfer is now complete. Invoke the // completion function, and based on its return value // either generate a stall or complete the message. usbs_control_return result; CYG_ASSERT( (usbs_control_return (*)(usbs_control_endpoint*, int))0 != ep0.common.complete_fn, \ "A completion function should be provided for OUT control messages"); result = (*ep0.common.complete_fn)(&ep0.common, 0); ep0.common.buffer = (unsigned char*) 0; ep0.common.buffer_size = 0; ep0.common.complete_fn = (usbs_control_return (*)(usbs_control_endpoint*, int)) 0; if (USBS_CONTROL_RETURN_HANDLED == result) { usbs_sa11x0_poke(EP0_CONTROL, EP0_SERVICED_OPR | EP0_DATA_END, EP0_DATA_END, EP0_OUT_READY); } else { usbs_sa11x0_poke(EP0_CONTROL, EP0_SERVICED_OPR | EP0_DATA_END | EP0_FORCE_STALL, EP0_FORCE_STALL, EP0_OUT_READY); } // Also remember to switch back to IDLE state ep0.ep_state = EP0_STATE_IDLE; } } else if (0 != (EP0_OUT_READY & hw_state)) { int emptied = usbs_sa11x0_ep0_empty_fifo(ep0.common.control_buffer); if (8 != emptied) { // This indicates a serious problem somewhere. Respond by // stalling. Hopefully the host will take some action that // sorts out the mess. usbs_sa11x0_poke(EP0_CONTROL, EP0_SERVICED_OPR | EP0_DATA_END | EP0_FORCE_STALL, EP0_FORCE_STALL, EP0_OUT_READY); } else { usbs_control_return result = USBS_CONTROL_RETURN_UNKNOWN; usb_devreq* req = (usb_devreq*) ep0.common.control_buffer; int length, direction, protocol, recipient; // Now we need to do some decoding of the data. A non-zero // length field indicates that there will be a subsequent // IN or OUT phase. The direction is controlled by the // top bit of the first byte. The protocol is determined // by other bits of the top byte. length = (req->length_hi << 8) | req->length_lo; direction = req->type & USB_DEVREQ_DIRECTION_MASK; protocol = req->type & USB_DEVREQ_TYPE_MASK; recipient = req->type & USB_DEVREQ_RECIPIENT_MASK; #if 0 DBG(("ep0, new control request: type %x, code %x\n", req->type, req->request)); DBG((" %s, length %d, value hi %x lo %x, index hi %x lo %x\n", (USB_DEVREQ_DIRECTION_OUT == direction) ? "out" : "in", length, req->value_hi, req->value_lo, req->index_hi, req->index_lo)); #endif if (0 != length){ // Clear the fifo straightaway. There is no harm in // doing this here. It may or may not do some good. usbs_sa11x0_poke(EP0_CONTROL, EP0_SERVICED_OPR, 0, EP0_OUT_READY); } if (USB_DEVREQ_TYPE_STANDARD == protocol) { // First see if the request can be handled entirely in // this module. if (USB_DEVREQ_SET_ADDRESS == req->request) { // The USB device address should be in value_lo. // No more data is expected. int address = req->value_lo; if ((0 != length) || (address > 127)) { result = USBS_CONTROL_RETURN_STALL; } else { // poke_value() cannot be used here because // setting the address does not take effect // until the status phase. *USBS_ADDRESS = address; result = USBS_CONTROL_RETURN_HANDLED; } } else if (USB_DEVREQ_GET_STATUS == req->request) { // GET_STATUS on the device as a whole is used to // check the remote-wakeup and self-powered bits. // GET_STATUS on an endpoint is used to determine // the halted condition. // GET_STATUS on anything else has to be left to // other code. if (USB_DEVREQ_RECIPIENT_DEVICE == recipient) { // The host should expect two bytes back. if ((2 == length) && (USB_DEVREQ_DIRECTION_IN == direction)) { ep0.common.control_buffer[0] = 0; // Not self-powered, no remote wakeup ep0.common.control_buffer[1] = 0; ep0.common.buffer = ep0.common.control_buffer; ep0.common.buffer_size = 2; result = USBS_CONTROL_RETURN_HANDLED; } else { result = USBS_CONTROL_RETURN_STALL; } } else if (USB_DEVREQ_RECIPIENT_ENDPOINT == recipient) { if ((2 == length) && (USB_DEVREQ_DIRECTION_IN == direction)) { int endpoint = req->index_lo; if (0 == endpoint) { // get-status on endpoint 0 is either undefined or always valid. // endpoint 0 is always up. ep0.common.control_buffer[0] = 0; result = USBS_CONTROL_RETURN_HANDLED; } #ifdef CYGPKG_DEVS_USB_SA11X0_EP1 else if (((USB_DEVREQ_INDEX_DIRECTION_OUT | 1) == endpoint) && (USBS_STATE_CONFIGURED == (ep0.common.state & USBS_STATE_MASK))) { ep0.common.control_buffer[0] = ep1.common.halted; result = USBS_CONTROL_RETURN_HANDLED; } #endif #ifdef CYGPKG_DEVS_USB_SA11X0_EP2 else if (((USB_DEVREQ_INDEX_DIRECTION_IN | 2) == endpoint) && (USBS_STATE_CONFIGURED == (ep0.common.state & USBS_STATE_MASK))) { ep0.common.control_buffer[0] = ep2.common.halted; result = USBS_CONTROL_RETURN_HANDLED; } #endif else { // An invalid endpoint has been specified or the // endpoint can only be examined in configured state. result = USBS_CONTROL_RETURN_STALL; } if (USBS_CONTROL_RETURN_HANDLED == result) { ep0.common.control_buffer[1] = 0; ep0.common.buffer = ep0.common.control_buffer; ep0.common.buffer_size = 2; } } else { result = USBS_CONTROL_RETURN_STALL; } } // Endpoint or device get-status } else if (USB_DEVREQ_CLEAR_FEATURE == req->request) { // CLEAR_FEATURE operates in much the same way as // GET_STATUS if (USB_DEVREQ_RECIPIENT_DEVICE == recipient) { // No data should be transferred, and only remote-wakeup can be cleared. if ((0 != length) || (USB_DEVREQ_FEATURE_DEVICE_REMOTE_WAKEUP != req->value_lo)) { result = USBS_CONTROL_RETURN_STALL; } else { // Clearing remote-wakeup is a no-op. result = USBS_CONTROL_RETURN_HANDLED; } } else if (USB_DEVREQ_RECIPIENT_ENDPOINT == recipient) { // The only feature that can be cleared is endpoint-halt, no data should be transferred. if ((0 != length) || (USB_DEVREQ_FEATURE_ENDPOINT_HALT != req->value_lo)) { result = USBS_CONTROL_RETURN_STALL; } else { int endpoint = req->index_lo; if (0 == endpoint) { // Clearing halt on endpoint 0 is always a no-op since that endpoint cannot be halted } #ifdef CYGPKG_DEVS_USB_SA11X0_EP1 else if (((USB_DEVREQ_INDEX_DIRECTION_OUT | 1) == endpoint) && (USBS_STATE_CONFIGURED == (ep0.common.state & USBS_STATE_MASK))) { ep1_set_halted(&ep1.common, false); result = USBS_CONTROL_RETURN_HANDLED; } #endif #ifdef CYGPKG_DEVS_USB_SA11X0_EP2 else if (((USB_DEVREQ_INDEX_DIRECTION_IN | 2) == endpoint) && (USBS_STATE_CONFIGURED == (ep0.common.state & USBS_STATE_MASK))) { ep2_set_halted(&ep2.common, false); result = USBS_CONTROL_RETURN_HANDLED; } #endif else { // Invalid endpoint or not in configured state. result = USBS_CONTROL_RETURN_STALL; } } } // Endpoing or device clear-feature } else if (USB_DEVREQ_SET_FEATURE == req->request) { // SET_FEATURE also operates in much the same way as // GET_STATUS if (USB_DEVREQ_RECIPIENT_DEVICE == recipient) { // The only valid feature that can be set is remote-wakeup, // which is not supported by the hardware. result = USBS_CONTROL_RETURN_STALL; } else if (USB_DEVREQ_RECIPIENT_ENDPOINT == recipient) { // Only the halt condition can be set, and no data should be transferred. // Halting endpoint 0 should probably be disallowed although the // standard does not explicitly say so. if ((0 != length) || (USB_DEVREQ_FEATURE_ENDPOINT_HALT != req->value_lo) || (USBS_STATE_CONFIGURED != (ep0.common.state & USBS_STATE_MASK))) { result = USBS_CONTROL_RETURN_STALL; } else { int endpoint = req->index_lo; if (0) { } #ifdef CYGPKG_DEVS_USB_SA11X0_EP1 else if ((USB_DEVREQ_INDEX_DIRECTION_OUT | 1) == endpoint) { ep1_set_halted(&ep1.common, true); result = USBS_CONTROL_RETURN_HANDLED; } #endif #ifdef CYGPKG_DEVS_USB_SA11X0_EP2 else if ((USB_DEVREQ_INDEX_DIRECTION_IN | 2) == endpoint) { ep2_set_halted(&ep2.common, true); result = USBS_CONTROL_RETURN_HANDLED; } #endif else { result = USBS_CONTROL_RETURN_STALL; } } } // Endpoint or device set-feature } // If the result has not been handled yet, pass it to // the installed callback function (if any). if (USBS_CONTROL_RETURN_UNKNOWN == result) { if ((usbs_control_return (*)(usbs_control_endpoint*, void*))0 != ep0.common.standard_control_fn) { result = (*ep0.common.standard_control_fn)(&ep0.common, ep0.common.standard_control_data); } } #if 1 if ((USBS_CONTROL_RETURN_UNKNOWN == result) && (USB_DEVREQ_SET_INTERFACE == req->request)) { // This code should not be necessary. For // non-trivial applications which involve // alternate interfaces and the like, this request // should be handled by the application itself. // For other applications, the default handler // will ignore this request so we end up falling // through without actually handling the request // and hence returning a stall condition. That // is legitimate behaviour according to the standard. // // However, there are appear to be problems with // the SA1110 USB hardware when it comes to stall // conditions: they appear to affect some // subsequent messages from target to host as // well. Hence rather than returning a stall // condition this code instead generates a dummy // reply, which is also valid according to the // standard. This avoids complications with certain // USB compliance testers. if ((0 != length) || (0 != req->value_hi) || (0 != req->index_hi) || (USBS_STATE_CONFIGURED != (ep0.common.state & USBS_STATE_MASK))) { result = USBS_CONTROL_RETURN_STALL; } else { int interface_id; int alternate; CYG_ASSERT( (1 == ep0.common.enumeration_data->device.number_configurations) && \ (1 == ep0.common.enumeration_data->total_number_interfaces), \ "Higher level code should have handled this request"); interface_id = req->index_lo; alternate = req->value_lo; if ((interface_id != ep0.common.enumeration_data->interfaces[0].interface_id) || (alternate != ep0.common.enumeration_data->interfaces[0].alternate_setting)) { result = USBS_CONTROL_RETURN_STALL; } else { result = USBS_CONTROL_RETURN_HANDLED; } } } #endif // If the result has still not been handled, leave it to // the default implementation in the USB slave common package if (USBS_CONTROL_RETURN_UNKNOWN == result) { result = usbs_handle_standard_control(&ep0.common); } } else { // The other three types of control message can be // handled by similar code. usbs_control_return (*callback_fn)(usbs_control_endpoint*, void*); void* callback_arg; //DBG(("non-standard control request %x", req->request)); if (USB_DEVREQ_TYPE_CLASS == protocol) { callback_fn = ep0.common.class_control_fn; callback_arg = ep0.common.class_control_data; } else if (USB_DEVREQ_TYPE_VENDOR == protocol) { callback_fn = ep0.common.vendor_control_fn; callback_arg = ep0.common.vendor_control_data; } else { callback_fn = ep0.common.reserved_control_fn; callback_arg = ep0.common.reserved_control_data; } if ((usbs_control_return (*)(usbs_control_endpoint*, void*)) 0 == callback_fn) { result = USBS_CONTROL_RETURN_STALL; } else { result = (*callback_fn)(&ep0.common, callback_arg); } } //DBG(("Control request done, %d\n", result)); if (USBS_CONTROL_RETURN_HANDLED != result) { // This control request cannot be handled. Generate a stall. usbs_sa11x0_poke(EP0_CONTROL, EP0_FORCE_STALL | EP0_SERVICED_OPR | EP0_DATA_END, EP0_FORCE_STALL, EP0_OUT_READY); } else { // The control request has been handled. Is there any more // data to be transferred? if (0 == length) { usbs_sa11x0_poke(EP0_CONTROL, EP0_SERVICED_OPR | EP0_DATA_END, EP0_DATA_END, EP0_OUT_READY); } else { // The endpoint should now go into IN or OUT mode while the // remaining data is transferred. ep0.transmitted = 0; ep0.length = length; if (USB_DEVREQ_DIRECTION_OUT == direction) { // Wait for the next packet from the host. ep0.ep_state = EP0_STATE_OUT; CYG_ASSERT( (unsigned char*) 0 != ep0.common.buffer, "A receive buffer should have been provided"); CYG_ASSERT( (usbs_control_return (*)(usbs_control_endpoint*, int))0 != ep0.common.complete_fn, \ "A completion function should be provided for OUT control messages"); } else { ep0.ep_state = EP0_STATE_IN; usbs_sa11x0_ep0_fill_fifo(); } } } // Control message handled } // Received 8-byte control message } // Idle state, i.e. control message } // ep0_dsr #ifdef CYGPKG_DEVS_USB_SA11X0_EP1 // ---------------------------------------------------------------------------- // Endpoint 1 is used for OUT transfers, i.e. receive operations. Only // the bulk protocol is supported by the hardware. The semantics allow // for two different modes of operation: higher-level code can ask for // exactly one or more bulk packets of 64 bytes each, allowing buffer // requirements to be determined from a header; alternatively the // rx request can just supply a large buffer. Processing the first // packet of a larger transfer separately does not introduce any // special problems at the protocol level. // // It is not legal to receive just part of a packet and expect the // hardware or the driver to buffer the rest. Not all hardware will // be capable of doing this buffering, and there should not be // a driver design requirement to provide buffering space. // // // The hardware design for endpoint 1 is flawed in a number of // respects. The receive fifo is only 20 bytes, less than the packet // size, so it is essential to use DMA (there is a configuration // option to allow for communication protocols where packets will // never exceed 16 bytes, but that is not the normal case). The DMA // engine is triggered by a receive-fifo-service high-water mark // bit. DMA transfers operate in bursts of eight bytes. Therefore // it would make sense if the high-water mark was set when the // receive fifo contained eight bytes or more. // // Instead the high-water mark is set when the fifo contains twelve // bytes or more. Worse, there is no way of measuring how many bytes // there are left in the fifo without actually extracting those bytes. // // For a full-size 64-byte packet, the first 56 bytes will be // transferred by DMA and the remainder will remain in the fifo. For a // partial packet of between 56 and 63 bytes, the first 56 bytes will // be transferred by DMA and the remainder will remain in the fifo. There // is no way to distinguish between these scenarios without emptying // the fifo. // // The result is that there is never any point in attempting a DMA // transfer of more than 56 bytes, and for every endpoint 1 interrupt // it is necessary to read the remainder from the fifo. This adds // a lot of software overhead, and it is not clear that DMA is // particularly useful. It is still necessary because of the limited // fifo size. // // // Because DMA involves the use of physical rather than virtual // memory, there are also cache interaction problems. Specifically it // would be necessary to invalidate cache lines after a DMA transfer // has completed, but that only works sensibly if the buffer is // aligned to a cache-line boundary and is a multiple of the // cache-line size. Imposing such restrictions on higher-level code // is undesirable. Also the DMA engines have an apparently undocumented // restriction that the buffer must be eight-byte aligned. // // To work around all these problems, the receive code works in terms // of a small private buffer. After a packet has been received, data // will be copied from this private buffer to the destination. Obviously // this copy operation is overhead and, because the code is expected // to run at DSR level, However the copy operation is limited to at // most 64 bytes, which is not good but not disastrous either. // // For data transfers the entry points are: // // 1) ep1_start_rx_packet() - prepare to receive another packet from // the host. // 2) ep1_clear_error() - an error condition has occurred (CRC, // bit-stuffing, fifo overrun). It appears that the only way // to clear this is to clear the receive-packet-complete bit, // which unfortunately allows in another packet from the host // before we are ready for it. Doing anything else while // the error bit is set does not work, for example it is not // possible to empty the fifo by hand. // 3) ep1_process_packet() - a whole packet has been received // and now needs to be moved into application space. // // These three routines are called by the start_rx() routine and // by the DSR. There are different implementations for DMA and // non-DMA. // // There is another hardware problem: the receive-packet-complete bit // comes up with the wrong default value, allowing the host to start // transmitting before the target is ready to receive. Unfortunately // there is not much that can be done about this: the // receive-packet-complete bit cannot be set by software and the OUT // max register has a minimum size of eight bytes. Fortunately for // many protocols the target-side code has a chance to start a receive // before the host is allowed to send, so this problem is mostly // ignored for now. // // Another potential problem arises if the host sends more data than // is expected for a given transfer. It would be possible to address // this by manipulating the OUT max packet register and getting the // hardware to generate protocol violation stalls. This would also // eliminate the need to test for buffer overflows. For now it is // left to higher-level code to sort it all out. #ifdef CYGNUM_DEVS_USB_SA11X0_EP1_DMA_CHANNEL // DMA needs an area of physical memory. To avoid conflicts with // the cached shadow of this memory, this area needs to start at // a cache line boundary and there must be padding at the end // to the next cache line boundary, thus ensuring that the // processor will not accidentally overwrite the physical // memory because it is manipulating some other variable. // // NOTE: at the time of writing the toolchain has a problem with // the aligned attribute, so instead the start alignment has // to be handled in software. # define EP1_DMA_MTU 56 # define EP1_DMA_BUFSIZE ((EP1_DMA_MTU + HAL_DCACHE_LINE_SIZE - 1) - \ ((EP1_DMA_MTU + HAL_DCACHE_LINE_SIZE - 1) % HAL_DCACHE_LINE_SIZE)) # define EP1_DMA_ALLOCSIZE (EP1_DMA_BUFSIZE + HAL_DCACHE_LINE_SIZE - 1) static unsigned char ep1_dma_data[EP1_DMA_ALLOCSIZE]; // This variable cannot be initialized statically, instead it is // set by ep1_init(). It corresponds to the physical address // for the buffer. static unsigned char* ep1_dma_buf; static void ep1_start_rx_packet(void) { int dma_size = EP1_DMA_MTU; // This assertion does not always hold: clearing an error condition // involves the packet-complete bit so another message may have // started to arrive. // CYG_ASSERT( 0 == (EP1_FIFO_NOT_EMPTY & *EP1_CONTROL), "The receive fifo should be empty"); CYG_ASSERT( 0 == ((DMA_CONTROL_RUN | DMA_CONTROL_START_A) & *EP1_DMA_STATUS), "EP1 DMA should be inactive"); #ifdef FAILURES ep1_failure = (ep1_failure + 1) % 32; if (0 == ep1_failure) { dma_size = 8; } #endif // The full flexibility of the DMA engines is not required here, // specifically the automatic chaining between buffers A and B. // Instead always using buffer A is sufficient. To avoid the // However the hardware still requires the software to alternate // between A and B. To avoid switching between buffers during a // transfer an excessive size field is used, EP1_MTU rather than // EP1_DMA_MTU, and hence the DMA transfer will never complete. // // With some silicon revisions writing to the DMA registers does // not always work either, so a retry is in order. Possibly // some short delays immediately after the clear and before the // set would be sufficient. *EP1_DMA_CONTROL_CLEAR = DMA_CONTROL_CLEAR_ALL; if (0 == (DMA_STATUS_BUFFER_IN_USE & *EP1_DMA_STATUS)) { ep1.using_buf_a = true; usbs_sa11x0_poke_value(EP1_DMA_BUF_A_ADDRESS, (unsigned int) ep1_dma_buf); usbs_sa11x0_poke_value(EP1_DMA_BUF_A_SIZE, dma_size); *EP1_DMA_CONTROL_SET = DMA_CONTROL_RUN | DMA_CONTROL_START_A; } else { ep1.using_buf_a = false; usbs_sa11x0_poke_value(EP1_DMA_BUF_B_ADDRESS, (unsigned int) ep1_dma_buf); usbs_sa11x0_poke_value(EP1_DMA_BUF_B_SIZE, dma_size); *EP1_DMA_CONTROL_SET = DMA_CONTROL_RUN | DMA_CONTROL_START_B; } // This should not be necessary, but occasionally the equivalent // operation during ep1_init() fails. Strictly speaking it should // be calling poke_value(), but the added overheads for that are // not worthwhile. *USBS_OUT_SIZE = EP1_MTU - 1; // Now allow the host to send the packet. usbs_sa11x0_poke(EP1_CONTROL, EP1_PACKET_COMPLETE | EP1_SENT_STALL, 0, EP1_PACKET_COMPLETE | EP1_SENT_STALL | EP1_FORCE_STALL); } // Clear an error condition following a CRC, bit stuffing or overrun // error. The only reliable way to do this is to halt DMA and clear // the packet-complete bit. Unfortunately this allows the host to send // another packet immediately, before start_rx_packet can be called, // introducing another race condition. The hardware does not appear // to offer any alternatives. static void ep1_clear_error(void) { *EP1_DMA_CONTROL_CLEAR = DMA_CONTROL_CLEAR_ALL; usbs_sa11x0_poke(EP1_CONTROL, EP1_PACKET_COMPLETE | EP1_SENT_STALL, 0, EP1_PACKET_COMPLETE | EP1_PACKET_ERROR | EP1_SENT_STALL | EP1_FORCE_STALL | EP1_FIFO_NOT_EMPTY); // Clearing the packet-complete bit may cause the host to send // another packet, immediately causing another error, so this // assertion does not hold. // CYG_ASSERT( 0 == (*EP1_CONTROL & (EP1_PACKET_ERROR | EP1_FIFO_NOT_EMPTY)), "Receive error should have been cleared"); } // A packet has been received. Some of it may still be in the fifo // and must be extracted by hand. The data then has to copied to // a higher-level buffer. static int ep1_process_packet(void) { int pkt_size; // First, work out how much data has been processed by the DMA // engine. This is the amount originally poked into the size // register minus its current value. *EP1_DMA_CONTROL_CLEAR = DMA_CONTROL_CLEAR_ALL; if (ep1.using_buf_a) { pkt_size = EP1_DMA_MTU - *EP1_DMA_BUF_A_SIZE; } else { pkt_size = EP1_DMA_MTU - *EP1_DMA_BUF_B_SIZE; } CYG_ASSERT( 0 == (pkt_size % DMA_BURST_SIZE), "DMA transfers must be in multiples of the burst size"); // Move these bytes from physical memory to the target buffer. if ((pkt_size > 0) && ((ep1.fetched + pkt_size) < ep1.common.buffer_size)) { memcpy(ep1.common.buffer + ep1.fetched, ep1_dma_buf, pkt_size); } // Copy remaining bytes into the target buffer directly. // The DMA buffer could be used instead, moving the memcpy() // down and avoiding the need for a buffer overflow check // inside the loop, but at the cost of accessing physical // memory every time. That cost is too high. while (1) { int status = *EP1_CONTROL; if ((EP1_PACKET_COMPLETE | EP1_PACKET_ERROR) == ((EP1_PACKET_COMPLETE | EP1_PACKET_ERROR) & status)) { break; } else if (0 == (EP1_FIFO_NOT_EMPTY & status)) { break; } else { int datum = *EP1_DATA; if (ep1.fetched < ep1.common.buffer_size) { ep1.common.buffer[ep1.fetched + pkt_size] = datum; } pkt_size++; } } ep1.fetched += pkt_size; return pkt_size; } #else // Transfers not involving DMA. Obviously these are much simpler // but restricted to packets of 16 bytes. static void ep1_start_rx_packet(void) { // Nothing to be done, just let the host send a packet and it will // end up in the fifo. usbs_sa11x0_poke(EP1_CONTROL, EP1_PACKET_COMPLETE | EP1_SENT_STALL, 0, EP1_PACKET_COMPLETE | EP1_SENT_STALL | EP1_FORCE_STALL); } static void ep1_clear_error(void) { usbs_sa11x0_poke(EP1_CONTROL, EP1_PACKET_COMPLETE | EP1_SENT_STALL, 0, EP1_PACKET_COMPLETE | EP1_SENT_STALL | EP1_FORCE_STALL); } static int ep1_process_packet(void) { int pkt_size = 0; while (0 != (*EP1_CONTROL & EP1_FIFO_NOT_EMPTY)) { int datum = *EP1_DATA; pkt_size++; if (ep1.fetched < ep1.common.buffer_size) { ep1.common.buffer[ep1.fetched + pkt_size] = datum; } } return pkt_size; } #endif // Complete a transfer. This takes care of invoking the completion // callback and resetting the buffer. static void ep1_rx_complete(int result) { void (*complete_fn)(void*, int) = ep1.common.complete_fn; void* complete_data = ep1.common.complete_data; ep1.common.buffer = (unsigned char*) 0; ep1.common.buffer_size = 0; ep1.common.complete_fn = (void (*)(void*, int)) 0; ep1.common.complete_data = (void*) 0; if ((void (*)(void*, int))0 != complete_fn) { (*complete_fn)(complete_data, result); } } // Start a transmission. This functionality is overloaded to cope with // waiting for stalls to complete. static void ep1_start_rx(usbs_rx_endpoint* endpoint) { CYG_ASSERT( endpoint == &ep1.common, "USB data transfer involves the wrong endpoint"); // Is this endpoint currently stalled? If so then a size of 0 can // be used to block until the stall condition is clear, anything // else should result in an immediate callback. if (ep1.common.halted) { if (0 != ep1.common.buffer_size) { ep1_rx_complete(-EAGAIN); } } else if (0 == ep1.common.buffer_size) { // A check to see if the endpoint is halted. It isn't. ep1_rx_complete(0); } else { int status = *EP1_CONTROL; CYG_ASSERT((void*) 0 != ep1.common.buffer, "USB receives should not override the interrupt vectors"); // This indicates the start of a transfer. ep1.fetched = 0; // The sent-stall bit may get set by hardware because of // a protocol violation. If so it must be cleared here. if (0 != (status & EP1_SENT_STALL)) { usbs_sa11x0_poke(EP1_CONTROL, EP1_SENT_STALL, 0, EP1_SENT_STALL | EP1_FORCE_STALL); status = *EP1_CONTROL; } // The bogus initial value for the receive-packet-complete // bit means that we may start off with an error condition. if ((EP1_PACKET_COMPLETE | EP1_PACKET_ERROR) == (status & (EP1_PACKET_COMPLETE | EP1_PACKET_ERROR))) { ep1_clear_error(); ep1_start_rx_packet(); } else if (0 != (status & EP1_FIFO_NOT_EMPTY)) { // No error but data in the fifo. This implies a small // initial packet, all held in the fifo. #ifdef CYGNUM_DEVS_USB_SA11X0_EP1_DMA_CHANNEL *EP1_DMA_BUF_A_SIZE = EP1_MTU; ep1.using_buf_a = true; #endif (void) ep1_process_packet(); ep1_rx_complete(ep1.fetched); } else { // Start a new transfer. ep1_start_rx_packet(); } } } static void ep1_set_halted(usbs_rx_endpoint* endpoint, cyg_bool new_value) { CYG_ASSERT( endpoint == &ep1.common, "USB set-stall operation involves the wrong endpoint"); if (ep1.common.halted == new_value) { return; } if (new_value) { // The endpoint should be stalled. There is a potential race // condition here with a current transfer. Updating the // stalled flag means that the dsr will do nothing. ep1.common.halted = true; HAL_REORDER_BARRIER(); // Now perform the actual stall. If we are in the middle of a // transfer then the stall bit may not get set for a while, so // poke() is inappropriate. *EP1_CONTROL = EP1_FORCE_STALL; } else { // The stall condition should be cleared. First take care of // things at the hardware level so that a new transfer is // allowed. usbs_sa11x0_poke(EP1_CONTROL, EP1_SENT_STALL, 0, EP1_SENT_STALL | EP1_FORCE_STALL); // Now allow new transfers to begin. ep1.common.halted = false; } } // The DSR is invoked following an interrupt. According to the docs an // endpoint 1 interrupt can only happen if the receive-packet-complete // bit is set. static void usbs_sa11x0_ep1_dsr(void) { int status = *EP1_CONTROL; // This assertion does not always hold. During long runs // spurious interrupts have been observed. // CYG_ASSERT( 0 != (status & EP1_PACKET_COMPLETE), "ep1 dsr should only be invoked when there is data"); if (0 == (status & EP1_PACKET_COMPLETE)) { return; } if (ep1.common.halted) { // Do nothing. What may have happened is that a transfer // was in progress when the stall bit was set. The // set_halted() call above will have taken care of things. return; } // The sent-stall bit should never get set, since we always // accept full-size 64-byte packets. Just in case... if (0 != (status & EP1_SENT_STALL)) { DBG(("ep1_dsr(), sent-stall bit\n")); usbs_sa11x0_poke(EP1_CONTROL, EP1_SENT_STALL, 0, EP1_SENT_STALL | EP1_FORCE_STALL); } // Was there a receive error (CRC, bit-stuffing, fifo-overrun?). // Whichever bits of the current packet have been received must be // discarded, and the current packet must be retried. if (0 != (status & EP1_PACKET_ERROR)) { INCR_STAT(ep1_errors); ep1_clear_error(); ep1_start_rx_packet(); } else { // Another packet has been received. Process it, which may // complete the transfer or it may leave more to be done. // // The hardware starts with the wrong default value for // the receive-packet-complete bit, so a packet may arrive // even though no rx operation has started yet. The // packets must be ignored for now. start_rx_packet() // will detect data in the fifo and do the right thing. int pkt_size; if ((unsigned char*)0 != ep1.common.buffer) { pkt_size = ep1_process_packet(); INCR_STAT(ep1_receives); if (0 != (EP1_PACKET_ERROR & *EP1_CONTROL)) { CYG_ASSERT( 0, "an error has occurred inside ep1_process_packet()\n"); } else if ((ep1.fetched != ep1.common.buffer_size) && (0 != pkt_size) && (0 == (ep1.fetched % EP1_MTU))) { ep1_start_rx_packet(); } else if (ep1.fetched > ep1.common.buffer_size) { // The host has sent too much data. ep1_rx_complete(-EMSGSIZE); } else { #if 0 int i; diag_printf("------------------------------------------------------\n"); diag_printf("rx: buf %x, total size %d\n", ep1.common.buffer, ep1.fetched); for (i = 0; (i < ep1.fetched) && (i < 128); i+= 8) { diag_printf("rx %x %x %x %x %x %x %x %x\n", ep1.common.buffer[i+0], ep1.common.buffer[i+1], ep1.common.buffer[i+2], ep1.common.buffer[i+3], ep1.common.buffer[i+4], ep1.common.buffer[i+5], ep1.common.buffer[i+6], ep1.common.buffer[i+7]); } diag_printf("------------------------------------------------------\n"); #endif ep1_rx_complete(ep1.fetched); } } } } // Initialization. // // This may get called during system start-up or following a reset // from the host. static void usbs_sa11x0_ep1_init(void) { #ifdef CYGNUM_DEVS_USB_SA11X0_EP1_DMA_CHANNEL // What is the physical address that should be used for // transfers? unsigned int phys; HAL_VIRT_TO_PHYS_ADDRESS( ep1_dma_data, phys); phys += (HAL_DCACHE_LINE_SIZE - 1); phys -= (phys % HAL_DCACHE_LINE_SIZE); CYG_ASSERT( 0 == (phys % HAL_DCACHE_LINE_SIZE), "DMA buffer must be aligned to a cache-line boundary"); ep1_dma_buf = (unsigned char*)phys; // Clear the DMA channel and fix the DMA address register. The // value is determined above. *EP1_DMA_CONTROL_CLEAR = DMA_CONTROL_CLEAR_ALL; *EP1_DMA_ADDRESS = EP1_DMA_ADDRESS_VALUE; #endif // Always allow the host to send full-size packets. If there is a // protocol problem and the host sends packets that are too large, // it will have to be handled at a level above the device driver. // // With some silicon revisions reading back the register does not // work, so poke_value() is not applicable. This may be an issue // with reset timing. *USBS_OUT_SIZE = EP1_MTU - 1; // Endpoints should never be halted during a start-up. ep1.common.halted = false; // If there has been a reset and there was a receive in progress, // abort it. This also takes care of sorting out the endpoint // fields ready for the next rx. ep1_rx_complete(-EPIPE); } #endif // CYGPKG_DEVS_USB_SA11X0_EP1 #ifdef CYGPKG_DEVS_USB_SA11X0_EP2 // ---------------------------------------------------------------------------- // Endpoint 2 is used for IN transfers, i.e. transmitting data to the // host. The code is mostly similar to that for endpoint 1, although // a little bit simpler (e.g. there is no need to worry about // buffer overflow, that is the host's problem). // // There is a flaw in the hardware design. If the transfer involves an // exact multiple of 64 bytes then according to the USB spec there // should be a terminating packet of 0 bytes. However the size of the // current outgoing packet is determined by the IN_SIZE register and // that only allows for packets between 1 and 256 bytes - even though // USB bulk transfers can only go up to 64 bytes. This can be worked // around at this level by transmitting an extra byte, at the risk of // upsetting host-side device drivers. Both higher-level and host-side // code need to be aware of this problem. // // Again there appear to be problems with the DMA engine. This time it // appears that the transmit-fifo-service bit does not always work // correctly. If you set up a DMA transfer for more than the packet // size than once the packet has gone out the fifo-service bit just // remains set, the DMA engine continues to fill the fifo, and the // data gets lost. Instead DMA can only happen one packet at a time. // The same issues regarding cache line alignment etc. arise, so // using a small buffer here is convenient. // // 1) process_packet moves a packet from the main transmit buffer // into the dma buffer. // 2) start_tx_packet() starts a transfer to the host // 3) clear_error() copes with error conditions. #ifdef CYGNUM_DEVS_USB_SA11X0_EP2_DMA_CHANNEL // See the equivalent EP1 DMA definitions. # define EP2_DMA_MTU 64 # define EP2_DMA_BUFSIZE ((EP2_DMA_MTU + HAL_DCACHE_LINE_SIZE - 1) - \ ((EP2_DMA_MTU + HAL_DCACHE_LINE_SIZE - 1) % HAL_DCACHE_LINE_SIZE)) # define EP2_DMA_ALLOCSIZE (EP2_DMA_BUFSIZE + HAL_DCACHE_LINE_SIZE - 1) static unsigned char ep2_dma_data[EP2_DMA_ALLOCSIZE]; static unsigned char* ep2_dma_buf; static void ep2_process_packet(void) { ep2.pkt_size = ep2.common.buffer_size - ep2.transmitted; if (ep2.pkt_size > EP2_MTU) { ep2.pkt_size = EP2_MTU; } // Work around the hardware's inability to send a zero-byte packet. if (0 == ep2.pkt_size) { ep2.pkt_size = 1; ep2_dma_buf[0] = 0; } else { memcpy(ep2_dma_buf, ep2.common.buffer + ep2.transmitted, ep2.pkt_size); } } static void ep2_tx_packet(void) { int dma_size, dma_control_settings; // CYG_ASSERT( 0 != (*EP2_CONTROL & EP2_FIFO_SERVICE), "Fifo should be empty"); // Halt any DMA that may still be going on (there should not // be any). Then work out the desired DMA settings for the // current packet. The DMA engine needs to transfer a multiple // of the burst size. If the packet size is not a multiple of // the burst size, this presents a minor problem. The chances // of an interrupt handler running in time to put the // remaining bytes into the fifo by hand are not good, so // instead more data is DMA'd in then is absolutely necessary // and the surplus bytes will be cleared out during the next // tx_packet. // // A possible optimisation is to detect small packets of // less than the fifo size and byte-stuff those, bypassing // DMA. It is not clear that would give any performance benefits. *EP2_DMA_CONTROL_CLEAR = DMA_CONTROL_CLEAR_ALL; dma_size = ep2.pkt_size + DMA_BURST_SIZE - 1; dma_size -= (dma_size % DMA_BURST_SIZE); CYG_ASSERT(dma_size > 0, "DMA calculations should result in a transfer of at least 8 bytes"); // Now clear the fifo, after DMA has stopped. usbs_sa11x0_poke(EP2_CONTROL, EP2_SENT_STALL, 0, EP2_SENT_STALL); // Should we be using buf_a or buf_b for this transfer? // Getting this wrong means that the DMA engine just idles. if (0 == (*EP2_DMA_STATUS & DMA_STATUS_BUFFER_IN_USE)) { usbs_sa11x0_poke_value(EP2_DMA_BUF_A_ADDRESS, (int) ep2_dma_buf); usbs_sa11x0_poke_value(EP2_DMA_BUF_A_SIZE, dma_size); dma_control_settings = DMA_CONTROL_RUN | DMA_CONTROL_START_A; } else { usbs_sa11x0_poke_value(EP2_DMA_BUF_B_ADDRESS, (int) ep2_dma_buf); usbs_sa11x0_poke_value(EP2_DMA_BUF_B_SIZE, dma_size); dma_control_settings = DMA_CONTROL_RUN | DMA_CONTROL_START_B; } // Poke the tx size register while the fifo is clearing. // This operation must be reliable or the host will get // confused by funny-sized packets. usbs_sa11x0_poke_value(USBS_IN_SIZE, ep2.pkt_size - 1); // The USB hardware must be updated before the DMA engine // starts filling the fifo. Otherwise ~48% of outgoing // packets fail with a DMA underrun. When called from // start_tx() there is a race condition: if the host // request comes in before the DMA starts then an // error interrupt will be raised, to be processed by // the DSR, and then the DMA engine gets updated again. // Locking the scheduler eliminates this race. cyg_drv_dsr_lock(); usbs_sa11x0_poke(EP2_CONTROL, EP2_PACKET_COMPLETE, 0, EP2_PACKET_COMPLETE | EP2_PACKET_ERROR | EP2_PACKET_UNDERRUN); *EP2_DMA_CONTROL_SET = dma_control_settings; cyg_drv_dsr_unlock(); // CYG_ASSERT(0 == (*EP2_CONTROL & EP2_FIFO_SERVICE), "DMA engine should have filled up the fifo by now"); } // Clearing an error should be a no-op when DMA is involved. // In practice clearing the packet-complete bit appears to // have some desirable effects, at the risk of the host // getting bogus data. This should only happen when there // is a real transfer in progress: an error early on is // likely because the PACKET_COMPLETE bit has a bogus initial // value. static void ep2_clear_error(void) { usbs_sa11x0_poke(EP2_CONTROL, EP2_PACKET_COMPLETE, 0, EP2_PACKET_COMPLETE | EP2_PACKET_ERROR | EP2_PACKET_UNDERRUN); } #else // EP2_DMA // When not using DMA, process_packet() is responsible for filling the // fifo and keeping a shadow copy in a static buffer. clear_error() // refills the fifo using the shadow copy. tx_packet() starts the // actual transfer. static unsigned char ep2_tx_buf[EP2_MTU]; static void ep2_process_packet() { int i; // Clear the fifo, just in case. usbs_sa11x0_poke(EP2_CONTROL, EP2_SENT_STALL, 0, EP2_SENT_STALL); ep2.pkt_size = ep2.common.buffer_size - ep2.transmitted; if (ep2.pkt_size > EP2_MTU) { ep2.pkt_size = EP2_MTU; } if (0 == ep2.pkt_size) { ep2.pkt_size = 1; ep2_tx_buf[i] = 0; *EP2_DATA = 0; } else { for (i = 0; i < ep2.pkt_size; i++) { unsigned int datum = ep2.common.buffer[ep2.transmitted + i]; ep2_tx_buf[i] = datum; *EP2_DATA = datum; } } } static void ep2_tx_packet() { usbs_sa11x0_poke_value(USBS_IN_SIZE, ep2.pkt_size - 1); usbs_sa11x0_poke(EP2_CONTROL, EP2_PACKET_COMPLETE, 0, EP2_PACKET_COMPLETE | EP2_PACKET_ERROR | EP2_PACKET_UNDERRUN); } static void ep2_clear_error() { int i; // Clear the fifo, just in case. usbs_sa11x0_poke(EP2_CONTROL, EP2_SENT_STALL, 0, EP2_SENT_STALL); for (i = 0; i < ep2.pkt_size; i++) { *EP2_DATA = ep2_tx_buf[i]; } } #endif // !EP2_DMA // A utility routine for completing a transfer. This takes care of the // callback as well as resetting the buffer. static void ep2_tx_complete(int result) { void (*complete_fn)(void*, int) = ep2.common.complete_fn; void* complete_data = ep2.common.complete_data; ep2.common.buffer = (unsigned char*) 0; ep2.common.buffer_size = 0; ep2.common.complete_fn = (void (*)(void*, int)) 0; ep2.common.complete_data = (void*) 0; if ((void (*)(void*, int))0 != complete_fn) { (*complete_fn)(complete_data, result); } } // The exported interface to start a transmission. static void ep2_start_tx(usbs_tx_endpoint* endpoint) { CYG_ASSERT( endpoint == &ep2.common, "USB data transfer involves the wrong endpoint"); // Is this endpoint currently stalled? If so then a size of 0 can // be used to block until the stall condition is clear, anything // else should result in an immediate callback. if (ep2.common.halted) { if (0 != ep2.common.buffer_size) { ep2_tx_complete(-EAGAIN); } } else if (0 == ep2.common.buffer_size) { // A check to see if the endpoint is halted. It isn't. ep2_tx_complete(0); } else { // There should not be any errors at the start of a // transmission, but if there is one then there is no safe way // to recover. process_packet() and tx_packet() will hopefully // do the right thing. CYG_ASSERT((void*) 0 != ep2.common.buffer, "Transmitting the interrupt vectors is unlikely to be useful"); #if 0 { int i; diag_printf("----------------------------------------------\n"); diag_printf("ep2_start_tx: buf %x, %d bytes\n", ep2.common.buffer, ep2.common.buffer_size); for (i = 0; (i < ep2.common.buffer_size) && (i < 128); i+= 8) { diag_printf("tx: %x %x %x %x %x %x %x %x\n", ep2.common.buffer[i+0], ep2.common.buffer[i+1], ep2.common.buffer[i+2], ep2.common.buffer[i+3], ep2.common.buffer[i+4], ep2.common.buffer[i+5], ep2.common.buffer[i+6], ep2.common.buffer[i+7]); } diag_printf("----------------------------------------------\n"); } #endif // Prepare the first packet for transmission, then send it. ep2.transmitted = 0; ep2_process_packet(); ep2_tx_packet(); } } static void ep2_set_halted(usbs_tx_endpoint* endpoint, cyg_bool new_value) { CYG_ASSERT(endpoint == &ep2.common, "USB set-stall operation involves the wrong endpoint"); if (ep2.common.halted == new_value) { return; } if (new_value) { // The endpoint should be stalled. There is a potential race // condition here with the current transfer and DSR invocation. // Updating the stalled flag means that the DSR will do nothing. ep2.common.halted = true; HAL_REORDER_BARRIER(); // Now perform the actual stall. This may be delayed by the hardware // so poke() cannot be used. *EP2_CONTROL = EP2_FORCE_STALL; // If in the middle of a transfer then that cannot be aborted, // the DMA engines etc. would get very confused. } else { // Take care of the hardware so that a new transfer is allowed. usbs_sa11x0_poke(EP2_CONTROL, EP2_SENT_STALL, 0, EP2_SENT_STALL | EP2_FORCE_STALL); ep2.common.halted = false; } } // The dsr will be invoked when the transmit-packet-complete bit is // set. Typically this happens when a packet has been completed // (surprise surprise) but it can also happen for error conditions. static void usbs_sa11x0_ep2_dsr(void) { int status = *EP2_CONTROL; // This assertion does not always hold - spurious interrupts have // been observed if you run for a few hours. // CYG_ASSERT( 0 != (status & EP2_PACKET_COMPLETE), "ep2 dsr should only be invoked when the packet-complete bit is set"); if (0 == (status & EP2_PACKET_COMPLETE)) { // Spurious interrupt, do nothing. } else if (ep2.common.halted) { // There is a possible race condition between a packet // completing and the stalled condition being set. // set_halted() above does everything that is needed. } else if (0 == ep2.pkt_size) { // This can happen because of the initial value for the // packet-complete bit, allowing the host to retrieve data // before the target is ready. The correct action is to do // nothing. } else if (0 != (status & (EP2_PACKET_ERROR | EP2_PACKET_UNDERRUN))) { // A transmit error occurred, the details are not important. INCR_STAT(ep2_errors); ep2_clear_error(); ep2_tx_packet(); } else { // Another packet has gone out. INCR_STAT(ep2_transmits); ep2.transmitted += ep2.pkt_size; if ((ep2.transmitted < ep2.common.buffer_size) || ((ep2.transmitted == ep2.common.buffer_size) && (0 == (ep2.common.buffer_size % EP2_MTU)))) { ep2_process_packet(); ep2_tx_packet(); } else { ep2_tx_complete(ep2.transmitted); } } } // Endpoint 2 initialization. // // This may be called during system start-up or following a reset // from the host. static void usbs_sa11x0_ep2_init(void) { #ifdef CYGNUM_DEVS_USB_SA11X0_EP2_DMA_CHANNEL // What is the physical address that should be used for // transfers? unsigned int phys; HAL_VIRT_TO_PHYS_ADDRESS(ep2_dma_data, phys); phys += (HAL_DCACHE_LINE_SIZE - 1); phys -= (phys % HAL_DCACHE_LINE_SIZE); CYG_ASSERT(0 == (phys % HAL_DCACHE_LINE_SIZE), "DMA buffer must be aligned to a cache-line boundary"); ep2_dma_buf = (unsigned char*) phys; // Clear the DMA channel completely, otherwise it may not be // possible to write the ADDRESS register. Then set the DMA // address register. The value is determined above. *EP2_DMA_CONTROL_CLEAR = DMA_CONTROL_CLEAR_ALL; *EP2_DMA_ADDRESS = EP2_DMA_ADDRESS_VALUE; #endif // Endpoints should never be halted after a reset ep2.common.halted = false; // If there has been a reset and there was a receive in progress, // abort it. This also takes care of clearing the endpoint // structure fields. ep2_tx_complete(-EPIPE); } #endif // CYGPKG_DEVS_USB_SA11X0_EP2 // ---------------------------------------------------------------------------- // Interrupt handling // // As much work as possible is deferred to the DSR (or to the debug // thread). Interrupts for the endpoints are never a problem: the // variuos packet-complete etc. bits ensure that the endpoints // remain quiescent until the relevant interrupt has been serviced. // Suspend and resume are more complicated. A suspend means that // there has been no activity for 3ms, which should be enough // time for the whole thing to be handled. A resume means that there // has been bus activity after a suspend, and again it is infrequent. // // Reset appears to be much more complicated. A reset means that the // host is holding the USB lines to a specific state for 10ms. This is // detected by the hardware, causing the USB controller to be reset // (i.e. any pending transfers are discarded, etc.). The reset bit in // the status register will be set, and an interrupt will be raised. // Now, in theory the correct thing to do is to process this // interrupt, block reset interrupts for the duration of these 10ms, // and wait for further activity such as the control message to set // the address. // // In practice this does not seem to work. Possibly the USB controller // gets reset continuously while the external reset signal is applied, // but I have not been able to confirm this. Messing about with the // reset interrupt control bit causes the system to go off into // never-never land. 10ms is too short a time to allow for manual // debugging of what happens. So for now the interrupt source is // blocked at the interrupt mask level and the dsr will do the // right thing. This causes a significant number of spurious interrupts // for the duration of the reset signal and not a lot else can happen. // Perform reset operations on all endpoints that have been // configured in. It is convenient to keep this in a separate // routine to allow for polling, where manipulating the // interrupt controller mask is a bad idea. static void usbs_sa11x0_handle_reset(void) { int old_state = ep0.common.state; // Any state change must be reported to higher-level code ep0.common.state = USBS_STATE_DEFAULT; if ((void (*)(usbs_control_endpoint*, void*, usbs_state_change, int))0 != ep0.common.state_change_fn) { (*ep0.common.state_change_fn)(&ep0.common, ep0.common.state_change_data, USBS_STATE_CHANGE_RESET, old_state); } // Reinitialize all the endpoints that have been configured in. usbs_sa11x0_ep0_init(); #ifdef CYGPKG_DEVS_USB_SA11X0_EP1 usbs_sa11x0_ep1_init(); #endif #ifdef CYGPKG_DEVS_USB_SA11X0_EP2 usbs_sa11x0_ep2_init(); #endif // After a reset we need to handle endpoint interrupts, reset // interrupts, and suspend interrupts. There should not be a // resume since we have not suspended, but leaving resume // interrupts enabled appears to be desirable with some hardware. // // With some silicon revisions it appears that a longer delay // is needed after reset, so this poke() may not work. if (!usbs_sa11x0_poke(USBS_CONTROL, CONTROL_INTR_ENABLE(CONTROL_EP_INTR_BITS|CONTROL_RESET_INTR|CONTROL_SUSPEND_INTR|CONTROL_RESUME_INTR), 0, CONTROL_INTR_CLEAR(CONTROL_EP_INTR_BITS|CONTROL_RESET_INTR|CONTROL_SUSPEND_INTR|CONTROL_RESUME_INTR))) { // DBG(("usbs_sa11x0_handle_reset(), update of control register failed, status %x\n", *USBS_STATUS)); } } // The DSR. This can be invoked directly by poll(), or via the usual // interrupt subsystem. It acts as per the current value of // isr_status_bits. If another interrupt goes off while this // DSR is running, there will be another invocation of the DSR and // the status bits will be updated. static void usbs_sa11x0_dsr(cyg_vector_t vector, cyg_ucount32 count, cyg_addrword_t data) { int status = 0; CYG_ASSERT(SA11X0_IRQ_USB_SERVICE_REQUEST == vector, "USB DSR should only be invoked for USB interrupts" ); CYG_ASSERT(0 == data, "The SA11X0 USB DSR needs no global data pointer"); // There is no atomic swap support, so interrupts have to be // blocked. It might be possible to do this via the USBS_CONTROL // register, but at the risk of messing up the status register // if another interrupt comes in. Blocking interrupts at the // processor level is less intrusive on the USB code. cyg_drv_isr_lock(); status = isr_status_bits; isr_status_bits = 0; cyg_drv_isr_unlock(); // Reset is special, since it invalidates everything else. // If the reset is still ongoing then do not attempt any // further processing, there will just be another interrupt. // Otherwise handle_reset() does the hard work. Unmasking // the interrupt means that another interrupt will occur // immediately if reset is still asserted, i.e. no threads // will run, but there is no easy way of triggering action // at the end of reset. if (0 != (status & STATUS_RESET_INTR)) { int new_status = *USBS_STATUS; if (0 == (new_status & STATUS_RESET_INTR)) { usbs_sa11x0_handle_reset(); } // This unmask is likely to cause another interrupt immediately cyg_drv_interrupt_unmask(SA11X0_IRQ_USB_SERVICE_REQUEST); } else { // Process resume first. Ignore any resumes when we are not // actually suspended yet, this happens mainly during system // startup. If there has been a state change to suspended // then we need a matching state change to resumed. if (0 != (status & STATUS_RESUME_INTR)) { int old_state = ep0.common.state; if (0 != (old_state & USBS_STATE_SUSPENDED)) { ep0.common.state &= ~USBS_STATE_SUSPENDED; if ((void (*)(usbs_control_endpoint*, void*, usbs_state_change, int))0 != ep0.common.state_change_fn) { (*ep0.common.state_change_fn)(&ep0.common, ep0.common.state_change_data, USBS_STATE_CHANGE_RESUMED, old_state); } // After a resume, all interrupts should be enabled. // In theory there is no need to worry about further // resume interrupts, but strange hardware behaviour // has been observed if resume interrupts are left // disabled. usbs_sa11x0_poke(USBS_CONTROL, CONTROL_INTR_ENABLE(CONTROL_EP_INTR_BITS|CONTROL_RESET_INTR|CONTROL_SUSPEND_INTR|CONTROL_RESUME_INTR), 0, CONTROL_INTR_CLEAR(CONTROL_EP_INTR_BITS|CONTROL_RESET_INTR|CONTROL_SUSPEND_INTR|CONTROL_RESUME_INTR)); } } // Now process endpoint interrupts. Control operations on // endpoint 0 may have side effects on the other endpoints // so it is better to leave them until last. #ifdef CYGPKG_DEVS_USB_SA11X0_EP1 if (0 != (status & STATUS_EP1_INTR)) { usbs_sa11x0_ep1_dsr(); } #endif #ifdef CYGPKG_DEVS_USB_SA11X0_EP2 if (0 != (status & STATUS_EP2_INTR)) { usbs_sa11x0_ep2_dsr(); } #endif if (0 != (status & STATUS_EP0_INTR)) { usbs_sa11x0_ep0_dsr(); } // Process suspend last, but only if there has not also been // a resume. A suspend immediately followed by a resume should // be ignored. A resume immediately followed by a suspend // would be unfortunate, but suspend means that there has been // at least 3ms of inactivity so the DSR latency would have // to be pretty bad. // // Total robustness is possible but requires more work in the ISR. if ((0 != (status & STATUS_SUSPEND_INTR)) && (0 == (status & STATUS_RESUME_INTR))) { int old_state = ep0.common.state; ep0.common.state |= USBS_STATE_SUSPENDED; if ((void (*)(usbs_control_endpoint*, void*, usbs_state_change, int))0 != ep0.common.state_change_fn) { (*ep0.common.state_change_fn)(&ep0.common, ep0.common.state_change_data, USBS_STATE_CHANGE_SUSPENDED, old_state); } // We are no longer interested in further suspend interrupts, // which could happen every 3 ms, but resume has become // very interesting. usbs_sa11x0_poke(USBS_CONTROL, CONTROL_INTR_ENABLE(CONTROL_EP_INTR_BITS | CONTROL_RESET_INTR | CONTROL_RESUME_INTR), 0, CONTROL_INTR_CLEAR(CONTROL_EP_INTR_BITS | CONTROL_RESET_INTR | CONTROL_RESUME_INTR)); } } } // ---------------------------------------------------------------------------- // Optionally the USB code can do most of its processing in a thread // rather than in a DSR. #ifdef CYGPKG_DEVS_USB_SA11X0_THREAD static unsigned char usbs_sa11x0_thread_stack[CYGNUM_DEVS_USB_SA11X0_THREAD_STACK_SIZE]; static cyg_thread usbs_sa11x0_thread; static cyg_handle_t usbs_sa11x0_thread_handle; static cyg_sem_t usbs_sa11x0_sem; static void usbs_sa11x0_thread_fn(cyg_addrword_t param) { for (;;) { cyg_semaphore_wait(&usbs_sa11x0_sem); usbs_sa11x0_dsr(SA11X0_IRQ_USB_SERVICE_REQUEST, 0, 0); } CYG_UNUSED_PARAM(cyg_addrword_t, param); } static void usbs_sa11x0_thread_dsr(cyg_vector_t vector, cyg_ucount32 count, cyg_addrword_t data) { CYG_ASSERT( 0 != isr_status_bits, "DSR's should only be scheduled when there is work to do"); cyg_semaphore_post(&usbs_sa11x0_sem); CYG_UNUSED_PARAM(cyg_vector_t, vector); CYG_UNUSED_PARAM(cyg_ucount32, count); CYG_UNUSED_PARAM(cyg_addrword_t, data); } #endif // ---------------------------------------------------------------------------- // The interrupt handler. This does as little as possible. static cyg_uint32 usbs_sa11x0_isr(cyg_vector_t vector, cyg_addrword_t data) { int old_status_bits = isr_status_bits; int status_bits; CYG_ASSERT(SA11X0_IRQ_USB_SERVICE_REQUEST == vector, "USB ISR should only be invoked for USB interrupts" ); CYG_ASSERT(0 == data, "The SA11X0 USB ISR needs no global data pointer" ); // Read the current status. Reset is special, it means that the // whole chip has been reset apart from the one bit in the status // register. Nothing should be done about this until the DSR sets // the endpoints back to a consistent state and re-enables // interrupts in the control register. status_bits = *USBS_STATUS; if (0 != (status_bits & STATUS_RESET_INTR)) { isr_status_bits = STATUS_RESET_INTR; *USBS_STATUS = status_bits; cyg_drv_interrupt_mask(SA11X0_IRQ_USB_SERVICE_REQUEST); } else { *USBS_STATUS = status_bits; isr_status_bits |= status_bits; } // Now keep the rest of the system happy. cyg_drv_interrupt_acknowledge(vector); return (old_status_bits != isr_status_bits) ? CYG_ISR_CALL_DSR : CYG_ISR_HANDLED; } // ---------------------------------------------------------------------------- // Polling support. This acts mostly like the interrupt handler: it // sets the isr status bits and causes the dsr to run. Reset has to be // handled specially: polling does nothing as long as reset is asserted. static void usbs_sa11x0_poll(usbs_control_endpoint* endpoint) { CYG_ASSERT( endpoint == &ep0.common, "USB poll involves the wrong endpoint"); if (0 != (isr_status_bits & STATUS_RESET_INTR)) { // Reset was detected the last time poll() was invoked. If // reset is still active, do nothing. Once the reset has // completed things can continue. if (0 == (STATUS_RESET_INTR & *USBS_STATUS)) { isr_status_bits = 0; usbs_sa11x0_handle_reset(); } } else { isr_status_bits = *USBS_STATUS; if (0 != (STATUS_RESET_INTR & isr_status_bits)) { // Reset has just been asserted. Do nothing, just continue // polling for the duration of the reset signal. } else if (0 != isr_status_bits) { usbs_sa11x0_dsr(SA11X0_IRQ_USB_SERVICE_REQUEST, 0, (cyg_addrword_t) 0); } } } // ---------------------------------------------------------------------------- // Initialization. void usbs_sa11x0_init(void) { // Start by disabling/resetting the hardware. This is easy. *USBS_CONTROL = CONTROL_DISABLE; *USBS_CONTROL = CONTROL_DISABLE; *USBS_CONTROL = CONTROL_DISABLE; // The USB bus is now tristated, preventing any communications. // This is a good thing, the situation should change only when // higher-level code has provided the enumeration data and done an // explicit start. usbs_sa11x0_ep0_init(); #ifdef CYGPKG_DEVS_USB_SA11X0_EP1 usbs_sa11x0_ep1_init(); #endif #ifdef CYGPKG_DEVS_USB_SA11X0_EP2 usbs_sa11x0_ep2_init(); #endif // If processing is supposed to happen in a thread rather // than in DSR, initialize the threads. #ifdef CYGPKG_DEVS_USB_SA11X0_THREAD cyg_semaphore_init(&usbs_sa11x0_sem, 0); cyg_thread_create(CYGNUM_DEVS_USB_SA11X0_THREAD_PRIORITY, &usbs_sa11x0_thread_fn, 0, "SA11X0 USB support", usbs_sa11x0_thread_stack, CYGNUM_DEVS_USB_SA11X0_THREAD_STACK_SIZE, &usbs_sa11x0_thread_handle, &usbs_sa11x0_thread ); cyg_thread_resume(usbs_sa11x0_thread_handle); #endif // It is also possible and desirable to install the interrupt // handler here, even though there will be no interrupts for a // while yet. cyg_drv_interrupt_create(SA11X0_IRQ_USB_SERVICE_REQUEST, 99, // priority 0, // data &usbs_sa11x0_isr, #ifdef CYGPKG_DEVS_USB_SA11X0_THREAD &usbs_sa11x0_thread_dsr, #else &usbs_sa11x0_dsr, #endif &usbs_sa11x0_intr_handle, &usbs_sa11x0_intr_data); cyg_drv_interrupt_attach(usbs_sa11x0_intr_handle); cyg_drv_interrupt_unmask(SA11X0_IRQ_USB_SERVICE_REQUEST); } // ---------------------------------------------------------------------------- // Testing support. usbs_testing_endpoint usbs_testing_endpoints[] = { { endpoint_type : USB_ENDPOINT_DESCRIPTOR_ATTR_CONTROL, endpoint_number : 0, endpoint_direction : USB_ENDPOINT_DESCRIPTOR_ENDPOINT_IN, endpoint : (void*) &ep0.common, #ifdef CYGVAR_DEVS_USB_SA11X0_EP0_DEVTAB_ENTRY devtab_entry : CYGDAT_DEVS_USB_SA11X0_DEVTAB_BASENAME "0c", #else devtab_entry : (const char*) 0, #endif min_size : 1, // zero-byte control transfers are meaningless max_size : 0x0FFFF, // limit imposed by protocol max_in_padding : 0, alignment : 0 }, #ifdef CYGPKG_DEVS_USB_SA11X0_EP1 { endpoint_type : USB_ENDPOINT_DESCRIPTOR_ATTR_BULK, endpoint_number : 1, endpoint_direction : USB_ENDPOINT_DESCRIPTOR_ENDPOINT_OUT, endpoint : (void*) &ep1.common, #ifdef CYGVAR_DEVS_USB_SA11X0_EP1_DEVTAB_ENTRY devtab_entry : CYGDAT_DEVS_USB_SA11X0_DEVTAB_BASENAME "1r", #else devtab_entry : (const char*) 0, #endif min_size : 1, max_size : -1, // No hardware or driver limitation max_in_padding : 0, alignment : 0 }, #endif #ifdef CYGPKG_DEVS_USB_SA11X0_EP2 { endpoint_type : USB_ENDPOINT_DESCRIPTOR_ATTR_BULK, endpoint_number : 2, endpoint_direction : USB_ENDPOINT_DESCRIPTOR_ENDPOINT_IN, endpoint : (void*) &ep2.common, #ifdef CYGVAR_DEVS_USB_SA11X0_EP2_DEVTAB_ENTRY devtab_entry : CYGDAT_DEVS_USB_SA11X0_DEVTAB_BASENAME "2w", #else devtab_entry : (const char*) 0, #endif min_size : 1, max_size : -1, // No hardware or driver limitation max_in_padding : 1, // hardware limitation alignment : 0 }, #endif USBS_TESTING_ENDPOINTS_TERMINATOR };