URL
https://opencores.org/ocsvn/or1k/or1k/trunk
Subversion Repositories or1k
[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [drivers/] [char/] [serial_amba.c] - Rev 1765
Compare with Previous | Blame | View Log
/* * linux/drivers/char/serial_amba.c * * Driver for AMBA serial ports * * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. * * Copyright 1999 ARM Limited * Copyright (C) 2000 Deep Blue Solutions Ltd. * * This program 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 of the License, or * (at your option) any later version. * * This program 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 this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * * This is a generic driver for ARM AMBA-type serial ports. They * have a lot of 16550-like features, but are not register compatable. * Note that although they do have CTS, DCD and DSR inputs, they do * not have an RI input, nor do they have DTR or RTS outputs. If * required, these have to be supplied via some other means (eg, GPIO) * and hooked into this driver. * * This could very easily become a generic serial driver for dumb UARTs * (eg, {82,16x}50, 21285, SA1100). */ #include <linux/config.h> #include <linux/module.h> #include <linux/errno.h> #include <linux/signal.h> #include <linux/sched.h> #include <linux/interrupt.h> #include <linux/tty.h> #include <linux/tty_flip.h> #include <linux/major.h> #include <linux/string.h> #include <linux/fcntl.h> #include <linux/ptrace.h> #include <linux/ioport.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/circ_buf.h> #include <linux/serial.h> #include <linux/console.h> #include <linux/sysrq.h> #include <asm/system.h> #include <asm/io.h> #include <asm/irq.h> #include <asm/uaccess.h> #include <asm/bitops.h> #include <asm/hardware/serial_amba.h> #define SERIAL_AMBA_NAME "ttyAM" #define SERIAL_AMBA_MAJOR 204 #define SERIAL_AMBA_MINOR 16 #define SERIAL_AMBA_NR 2 #define CALLOUT_AMBA_NAME "cuaam" #define CALLOUT_AMBA_MAJOR 205 #define CALLOUT_AMBA_MINOR 16 #define CALLOUT_AMBA_NR SERIAL_AMBA_NR #ifndef TRUE #define TRUE 1 #endif #ifndef FALSE #define FALSE 0 #endif #define DEBUG 0 #define DEBUG_LEDS 0 #if DEBUG_LEDS extern int get_leds(void); extern int set_leds(int); #endif /* * Access routines for the AMBA UARTs */ #define UART_GET_INT_STATUS(p) IO_READ((p)->uart_base + AMBA_UARTIIR) #define UART_GET_FR(p) IO_READ((p)->uart_base + AMBA_UARTFR) #define UART_GET_CHAR(p) IO_READ((p)->uart_base + AMBA_UARTDR) #define UART_PUT_CHAR(p, c) IO_WRITE((p)->uart_base + AMBA_UARTDR, (c)) #define UART_GET_RSR(p) IO_READ((p)->uart_base + AMBA_UARTRSR) #define UART_GET_CR(p) IO_READ((p)->uart_base + AMBA_UARTCR) #define UART_PUT_CR(p,c) IO_WRITE((p)->uart_base + AMBA_UARTCR, (c)) #define UART_GET_LCRL(p) IO_READ((p)->uart_base + AMBA_UARTLCR_L) #define UART_PUT_LCRL(p,c) IO_WRITE((p)->uart_base + AMBA_UARTLCR_L, (c)) #define UART_GET_LCRM(p) IO_READ((p)->uart_base + AMBA_UARTLCR_M) #define UART_PUT_LCRM(p,c) IO_WRITE((p)->uart_base + AMBA_UARTLCR_M, (c)) #define UART_GET_LCRH(p) IO_READ((p)->uart_base + AMBA_UARTLCR_H) #define UART_PUT_LCRH(p,c) IO_WRITE((p)->uart_base + AMBA_UARTLCR_H, (c)) #define UART_RX_DATA(s) (((s) & AMBA_UARTFR_RXFE) == 0) #define UART_TX_READY(s) (((s) & AMBA_UARTFR_TXFF) == 0) #define UART_TX_EMPTY(p) ((UART_GET_FR(p) & AMBA_UARTFR_TMSK) == 0) #define AMBA_UARTRSR_ANY (AMBA_UARTRSR_OE|AMBA_UARTRSR_BE|AMBA_UARTRSR_PE|AMBA_UARTRSR_FE) #define AMBA_UARTFR_MODEM_ANY (AMBA_UARTFR_DCD|AMBA_UARTFR_DSR|AMBA_UARTFR_CTS) /* * Things needed by tty driver */ static struct tty_driver ambanormal_driver, ambacallout_driver; static int ambauart_refcount; static struct tty_struct *ambauart_table[SERIAL_AMBA_NR]; static struct termios *ambauart_termios[SERIAL_AMBA_NR]; static struct termios *ambauart_termios_locked[SERIAL_AMBA_NR]; #if defined(CONFIG_SERIAL_AMBA_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) #define SUPPORT_SYSRQ #endif /* * Things needed internally to this driver */ /* * tmp_buf is used as a temporary buffer by serial_write. We need to * lock it in case the copy_from_user blocks while swapping in a page, * and some other program tries to do a serial write at the same time. * Since the lock will only come under contention when the system is * swapping and available memory is low, it makes sense to share one * buffer across all the serial ports, since it significantly saves * memory if large numbers of serial ports are open. */ static u_char *tmp_buf; static DECLARE_MUTEX(tmp_buf_sem); #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8) /* number of characters left in xmit buffer before we ask for more */ #define WAKEUP_CHARS 256 #define AMBA_ISR_PASS_LIMIT 256 #define EVT_WRITE_WAKEUP 0 struct amba_icount { __u32 cts; __u32 dsr; __u32 rng; __u32 dcd; __u32 rx; __u32 tx; __u32 frame; __u32 overrun; __u32 parity; __u32 brk; __u32 buf_overrun; }; /* * Static information about the port */ struct amba_port { unsigned int uart_base; unsigned int irq; unsigned int uartclk; unsigned int fifosize; unsigned int tiocm_support; void (*set_mctrl)(struct amba_port *, u_int mctrl); }; /* * This is the state information which is persistent across opens */ struct amba_state { struct amba_icount icount; unsigned int line; unsigned int close_delay; unsigned int closing_wait; unsigned int custom_divisor; unsigned int flags; struct termios normal_termios; struct termios callout_termios; int count; struct amba_info *info; }; #define AMBA_XMIT_SIZE 1024 /* * This is the state information which is only valid when the port is open. */ struct amba_info { struct amba_port *port; struct amba_state *state; struct tty_struct *tty; unsigned char x_char; unsigned char old_status; unsigned char read_status_mask; unsigned char ignore_status_mask; struct circ_buf xmit; unsigned int flags; #ifdef SUPPORT_SYSRQ unsigned long sysrq; #endif unsigned int event; unsigned int timeout; unsigned int lcr_h; unsigned int mctrl; int blocked_open; pid_t session; pid_t pgrp; struct tasklet_struct tlet; wait_queue_head_t open_wait; wait_queue_head_t close_wait; wait_queue_head_t delta_msr_wait; }; #ifdef CONFIG_SERIAL_AMBA_CONSOLE static struct console ambauart_cons; #endif static void ambauart_change_speed(struct amba_info *info, struct termios *old_termios); static void ambauart_wait_until_sent(struct tty_struct *tty, int timeout); #if 1 //def CONFIG_SERIAL_INTEGRATOR static void amba_set_mctrl_null(struct amba_port *port, u_int mctrl) { } static struct amba_port amba_ports[SERIAL_AMBA_NR] = { { uart_base: IO_ADDRESS(INTEGRATOR_UART0_BASE), irq: IRQ_UARTINT0, uartclk: 14745600, fifosize: 8, set_mctrl: amba_set_mctrl_null, }, { uart_base: IO_ADDRESS(INTEGRATOR_UART1_BASE), irq: IRQ_UARTINT1, uartclk: 14745600, fifosize: 8, set_mctrl: amba_set_mctrl_null, } }; #endif static struct amba_state amba_state[SERIAL_AMBA_NR]; static void ambauart_enable_rx_interrupt(struct amba_info *info) { unsigned int cr; cr = UART_GET_CR(info->port); cr |= AMBA_UARTCR_RIE | AMBA_UARTCR_RTIE; UART_PUT_CR(info->port, cr); } static void ambauart_disable_rx_interrupt(struct amba_info *info) { unsigned int cr; cr = UART_GET_CR(info->port); cr &= ~(AMBA_UARTCR_RIE | AMBA_UARTCR_RTIE); UART_PUT_CR(info->port, cr); } static void ambauart_enable_tx_interrupt(struct amba_info *info) { unsigned int cr; cr = UART_GET_CR(info->port); cr |= AMBA_UARTCR_TIE; UART_PUT_CR(info->port, cr); } static void ambauart_disable_tx_interrupt(struct amba_info *info) { unsigned int cr; cr = UART_GET_CR(info->port); cr &= ~AMBA_UARTCR_TIE; UART_PUT_CR(info->port, cr); } static void ambauart_stop(struct tty_struct *tty) { struct amba_info *info = tty->driver_data; unsigned long flags; save_flags(flags); cli(); ambauart_disable_tx_interrupt(info); restore_flags(flags); } static void ambauart_start(struct tty_struct *tty) { struct amba_info *info = tty->driver_data; unsigned long flags; save_flags(flags); cli(); if (info->xmit.head != info->xmit.tail && info->xmit.buf) ambauart_enable_tx_interrupt(info); restore_flags(flags); } /* * This routine is used by the interrupt handler to schedule * processing in the software interrupt portion of the driver. */ static void ambauart_event(struct amba_info *info, int event) { info->event |= 1 << event; tasklet_schedule(&info->tlet); } static void #ifdef SUPPORT_SYSRQ ambauart_rx_chars(struct amba_info *info, struct pt_regs *regs) #else ambauart_rx_chars(struct amba_info *info) #endif { struct tty_struct *tty = info->tty; unsigned int status, ch, rsr, flg, ignored = 0; struct amba_icount *icount = &info->state->icount; struct amba_port *port = info->port; status = UART_GET_FR(port); while (UART_RX_DATA(status)) { ch = UART_GET_CHAR(port); if (tty->flip.count >= TTY_FLIPBUF_SIZE) goto ignore_char; icount->rx++; flg = TTY_NORMAL; /* * Note that the error handling code is * out of the main execution path */ rsr = UART_GET_RSR(port); if (rsr & AMBA_UARTRSR_ANY) goto handle_error; #ifdef SUPPORT_SYSRQ if (info->sysrq) { if (ch && time_before(jiffies, info->sysrq)) { handle_sysrq(ch, regs, NULL, NULL); info->sysrq = 0; goto ignore_char; } info->sysrq = 0; } #endif error_return: *tty->flip.flag_buf_ptr++ = flg; *tty->flip.char_buf_ptr++ = ch; tty->flip.count++; ignore_char: status = UART_GET_FR(port); } out: tty_flip_buffer_push(tty); return; handle_error: if (rsr & AMBA_UARTRSR_BE) { rsr &= ~(AMBA_UARTRSR_FE | AMBA_UARTRSR_PE); icount->brk++; #ifdef SUPPORT_SYSRQ if (info->state->line == ambauart_cons.index) { if (!info->sysrq) { info->sysrq = jiffies + HZ*5; goto ignore_char; } } #endif } else if (rsr & AMBA_UARTRSR_PE) icount->parity++; else if (rsr & AMBA_UARTRSR_FE) icount->frame++; if (rsr & AMBA_UARTRSR_OE) icount->overrun++; if (rsr & info->ignore_status_mask) { if (++ignored > 100) goto out; goto ignore_char; } rsr &= info->read_status_mask; if (rsr & AMBA_UARTRSR_BE) flg = TTY_BREAK; else if (rsr & AMBA_UARTRSR_PE) flg = TTY_PARITY; else if (rsr & AMBA_UARTRSR_FE) flg = TTY_FRAME; if (rsr & AMBA_UARTRSR_OE) { /* * CHECK: does overrun affect the current character? * ASSUMPTION: it does not. */ *tty->flip.flag_buf_ptr++ = flg; *tty->flip.char_buf_ptr++ = ch; tty->flip.count++; if (tty->flip.count >= TTY_FLIPBUF_SIZE) goto ignore_char; ch = 0; flg = TTY_OVERRUN; } #ifdef SUPPORT_SYSRQ info->sysrq = 0; #endif goto error_return; } static void ambauart_tx_chars(struct amba_info *info) { struct amba_port *port = info->port; int count; if (info->x_char) { UART_PUT_CHAR(port, info->x_char); info->state->icount.tx++; info->x_char = 0; return; } if (info->xmit.head == info->xmit.tail || info->tty->stopped || info->tty->hw_stopped) { ambauart_disable_tx_interrupt(info); return; } count = port->fifosize; do { UART_PUT_CHAR(port, info->xmit.buf[info->xmit.tail]); info->xmit.tail = (info->xmit.tail + 1) & (AMBA_XMIT_SIZE - 1); info->state->icount.tx++; if (info->xmit.head == info->xmit.tail) break; } while (--count > 0); if (CIRC_CNT(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE) < WAKEUP_CHARS) ambauart_event(info, EVT_WRITE_WAKEUP); if (info->xmit.head == info->xmit.tail) { ambauart_disable_tx_interrupt(info); } } static void ambauart_modem_status(struct amba_info *info) { unsigned int status, delta; struct amba_icount *icount = &info->state->icount; status = UART_GET_FR(info->port) & AMBA_UARTFR_MODEM_ANY; delta = status ^ info->old_status; info->old_status = status; if (!delta) return; if (delta & AMBA_UARTFR_DCD) { icount->dcd++; #ifdef CONFIG_HARD_PPS if ((info->flags & ASYNC_HARDPPS_CD) && (status & AMBA_UARTFR_DCD) hardpps(); #endif if (info->flags & ASYNC_CHECK_CD) { if (status & AMBA_UARTFR_DCD) wake_up_interruptible(&info->open_wait); else if (!((info->flags & ASYNC_CALLOUT_ACTIVE) && (info->flags & ASYNC_CALLOUT_NOHUP))) { if (info->tty) tty_hangup(info->tty); } } } if (delta & AMBA_UARTFR_DSR) icount->dsr++; if (delta & AMBA_UARTFR_CTS) { icount->cts++; if (info->flags & ASYNC_CTS_FLOW) { status &= AMBA_UARTFR_CTS; if (info->tty->hw_stopped) { if (status) { info->tty->hw_stopped = 0; ambauart_enable_tx_interrupt(info); ambauart_event(info, EVT_WRITE_WAKEUP); } } else { if (!status) { info->tty->hw_stopped = 1; ambauart_disable_tx_interrupt(info); } } } } wake_up_interruptible(&info->delta_msr_wait); } static void ambauart_int(int irq, void *dev_id, struct pt_regs *regs) { struct amba_info *info = dev_id; unsigned int status, pass_counter = 0; #if DEBUG_LEDS // tell the world set_leds(get_leds() | RED_LED); #endif status = UART_GET_INT_STATUS(info->port); do { /* * FIXME: what about clearing the interrupts? */ if (status & (AMBA_UARTIIR_RTIS | AMBA_UARTIIR_RIS)) #ifdef SUPPORT_SYSRQ ambauart_rx_chars(info, regs); #else ambauart_rx_chars(info); #endif if (status & AMBA_UARTIIR_TIS) ambauart_tx_chars(info); if (status & AMBA_UARTIIR_MIS) ambauart_modem_status(info); if (pass_counter++ > AMBA_ISR_PASS_LIMIT) break; status = UART_GET_INT_STATUS(info->port); } while (status & (AMBA_UARTIIR_RTIS | AMBA_UARTIIR_RIS | AMBA_UARTIIR_TIS)); #if DEBUG_LEDS // tell the world set_leds(get_leds() & ~RED_LED); #endif } static void ambauart_tasklet_action(unsigned long data) { struct amba_info *info = (struct amba_info *)data; struct tty_struct *tty; tty = info->tty; if (!tty || !test_and_clear_bit(EVT_WRITE_WAKEUP, &info->event)) return; if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup) (tty->ldisc.write_wakeup)(tty); wake_up_interruptible(&tty->write_wait); } static int ambauart_startup(struct amba_info *info) { unsigned long flags; unsigned long page; int retval = 0; page = get_zeroed_page(GFP_KERNEL); if (!page) return -ENOMEM; save_flags(flags); cli(); if (info->flags & ASYNC_INITIALIZED) { free_page(page); goto errout; } if (info->xmit.buf) free_page(page); else info->xmit.buf = (unsigned char *) page; /* * Allocate the IRQ */ retval = request_irq(info->port->irq, ambauart_int, 0, "amba", info); if (retval) { if (capable(CAP_SYS_ADMIN)) { if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags); retval = 0; } goto errout; } info->mctrl = 0; if (info->tty->termios->c_cflag & CBAUD) info->mctrl = TIOCM_RTS | TIOCM_DTR; info->port->set_mctrl(info->port, info->mctrl); /* * initialise the old status of the modem signals */ info->old_status = UART_GET_FR(info->port) & AMBA_UARTFR_MODEM_ANY; /* * Finally, enable interrupts */ ambauart_enable_rx_interrupt(info); if (info->tty) clear_bit(TTY_IO_ERROR, &info->tty->flags); info->xmit.head = info->xmit.tail = 0; /* * Set up the tty->alt_speed kludge */ if (info->tty) { if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI) info->tty->alt_speed = 57600; if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI) info->tty->alt_speed = 115200; if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI) info->tty->alt_speed = 230400; if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP) info->tty->alt_speed = 460800; } /* * and set the speed of the serial port */ ambauart_change_speed(info, 0); info->flags |= ASYNC_INITIALIZED; restore_flags(flags); return 0; errout: restore_flags(flags); return retval; } /* * This routine will shutdown a serial port; interrupts are disabled, and * DTR is dropped if the hangup on close termio flag is on. */ static void ambauart_shutdown(struct amba_info *info) { unsigned long flags; if (!(info->flags & ASYNC_INITIALIZED)) return; save_flags(flags); cli(); /* Disable interrupts */ /* * clear delta_msr_wait queue to avoid mem leaks: we may free the irq * here so the queue might never be woken up */ wake_up_interruptible(&info->delta_msr_wait); /* * Free the IRQ */ free_irq(info->port->irq, info); if (info->xmit.buf) { unsigned long pg = (unsigned long) info->xmit.buf; info->xmit.buf = NULL; free_page(pg); } /* * disable all interrupts, disable the port */ UART_PUT_CR(info->port, 0); /* disable break condition and fifos */ UART_PUT_LCRH(info->port, UART_GET_LCRH(info->port) & ~(AMBA_UARTLCR_H_BRK | AMBA_UARTLCR_H_FEN)); if (!info->tty || (info->tty->termios->c_cflag & HUPCL)) info->mctrl &= ~(TIOCM_DTR|TIOCM_RTS); info->port->set_mctrl(info->port, info->mctrl); /* kill off our tasklet */ tasklet_kill(&info->tlet); if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags); info->flags &= ~ASYNC_INITIALIZED; restore_flags(flags); } static void ambauart_change_speed(struct amba_info *info, struct termios *old_termios) { unsigned int lcr_h, baud, quot, cflag, old_cr, bits; unsigned long flags; if (!info->tty || !info->tty->termios) return; cflag = info->tty->termios->c_cflag; #if DEBUG printk("ambauart_set_cflag(0x%x) called\n", cflag); #endif /* byte size and parity */ switch (cflag & CSIZE) { case CS5: lcr_h = AMBA_UARTLCR_H_WLEN_5; bits = 7; break; case CS6: lcr_h = AMBA_UARTLCR_H_WLEN_6; bits = 8; break; case CS7: lcr_h = AMBA_UARTLCR_H_WLEN_7; bits = 9; break; default: lcr_h = AMBA_UARTLCR_H_WLEN_8; bits = 10; break; // CS8 } if (cflag & CSTOPB) { lcr_h |= AMBA_UARTLCR_H_STP2; bits ++; } if (cflag & PARENB) { lcr_h |= AMBA_UARTLCR_H_PEN; bits++; if (!(cflag & PARODD)) lcr_h |= AMBA_UARTLCR_H_EPS; } if (info->port->fifosize > 1) lcr_h |= AMBA_UARTLCR_H_FEN; do { /* Determine divisor based on baud rate */ baud = tty_get_baud_rate(info->tty); if (!baud) baud = 9600; if (baud == 38400 && ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)) quot = info->state->custom_divisor; else quot = (info->port->uartclk / (16 * baud)) - 1; if (!quot && old_termios) { info->tty->termios->c_cflag &= ~CBAUD; info->tty->termios->c_cflag |= (old_termios->c_cflag & CBAUD); old_termios = NULL; } } while (quot == 0 && old_termios); /* As a last resort, if the quotient is zero, default to 9600 bps */ if (!quot) quot = (info->port->uartclk / (16 * 9600)) - 1; info->timeout = (info->port->fifosize * HZ * bits * quot) / (info->port->uartclk / 16); info->timeout += HZ/50; /* Add .02 seconds of slop */ if (cflag & CRTSCTS) info->flags |= ASYNC_CTS_FLOW; else info->flags &= ~ASYNC_CTS_FLOW; if (cflag & CLOCAL) info->flags &= ~ASYNC_CHECK_CD; else info->flags |= ASYNC_CHECK_CD; /* * Set up parity check flag */ #define RELEVENT_IFLAG(iflag) ((iflag) & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK)) info->read_status_mask = AMBA_UARTRSR_OE; if (I_INPCK(info->tty)) info->read_status_mask |= AMBA_UARTRSR_FE | AMBA_UARTRSR_PE; if (I_BRKINT(info->tty) || I_PARMRK(info->tty)) info->read_status_mask |= AMBA_UARTRSR_BE; /* * Characters to ignore */ info->ignore_status_mask = 0; if (I_IGNPAR(info->tty)) info->ignore_status_mask |= AMBA_UARTRSR_FE | AMBA_UARTRSR_PE; if (I_IGNBRK(info->tty)) { info->ignore_status_mask |= AMBA_UARTRSR_BE; /* * If we're ignoring parity and break indicators, * ignore overruns to (for real raw support). */ if (I_IGNPAR(info->tty)) info->ignore_status_mask |= AMBA_UARTRSR_OE; } /* first, disable everything */ save_flags(flags); cli(); old_cr = UART_GET_CR(info->port) &= ~AMBA_UARTCR_MSIE; if ((info->flags & ASYNC_HARDPPS_CD) || (cflag & CRTSCTS) || !(cflag & CLOCAL)) old_cr |= AMBA_UARTCR_MSIE; UART_PUT_CR(info->port, 0); restore_flags(flags); /* Set baud rate */ UART_PUT_LCRM(info->port, ((quot & 0xf00) >> 8)); UART_PUT_LCRL(info->port, (quot & 0xff)); /* * ----------v----------v----------v----------v----- * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L * ----------^----------^----------^----------^----- */ UART_PUT_LCRH(info->port, lcr_h); UART_PUT_CR(info->port, old_cr); } static void ambauart_put_char(struct tty_struct *tty, u_char ch) { struct amba_info *info = tty->driver_data; unsigned long flags; if (!tty || !info->xmit.buf) return; save_flags(flags); cli(); if (CIRC_SPACE(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE) != 0) { info->xmit.buf[info->xmit.head] = ch; info->xmit.head = (info->xmit.head + 1) & (AMBA_XMIT_SIZE - 1); } restore_flags(flags); } static void ambauart_flush_chars(struct tty_struct *tty) { struct amba_info *info = tty->driver_data; unsigned long flags; if (info->xmit.head == info->xmit.tail || tty->stopped || tty->hw_stopped || !info->xmit.buf) return; save_flags(flags); cli(); ambauart_enable_tx_interrupt(info); restore_flags(flags); } static int ambauart_write(struct tty_struct *tty, int from_user, const u_char * buf, int count) { struct amba_info *info = tty->driver_data; unsigned long flags; int c, ret = 0; if (!tty || !info->xmit.buf || !tmp_buf) return 0; save_flags(flags); if (from_user) { down(&tmp_buf_sem); while (1) { int c1; c = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE); if (count < c) c = count; if (c <= 0) break; c -= copy_from_user(tmp_buf, buf, c); if (!c) { if (!ret) ret = -EFAULT; break; } cli(); c1 = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE); if (c1 < c) c = c1; memcpy(info->xmit.buf + info->xmit.head, tmp_buf, c); info->xmit.head = (info->xmit.head + c) & (AMBA_XMIT_SIZE - 1); restore_flags(flags); buf += c; count -= c; ret += c; } up(&tmp_buf_sem); } else { cli(); while (1) { c = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE); if (count < c) c = count; if (c <= 0) break; memcpy(info->xmit.buf + info->xmit.head, buf, c); info->xmit.head = (info->xmit.head + c) & (AMBA_XMIT_SIZE - 1); buf += c; count -= c; ret += c; } restore_flags(flags); } if (info->xmit.head != info->xmit.tail && !tty->stopped && !tty->hw_stopped) ambauart_enable_tx_interrupt(info); return ret; } static int ambauart_write_room(struct tty_struct *tty) { struct amba_info *info = tty->driver_data; return CIRC_SPACE(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE); } static int ambauart_chars_in_buffer(struct tty_struct *tty) { struct amba_info *info = tty->driver_data; return CIRC_CNT(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE); } static void ambauart_flush_buffer(struct tty_struct *tty) { struct amba_info *info = tty->driver_data; unsigned long flags; #if DEBUG printk("ambauart_flush_buffer(%d) called\n", MINOR(tty->device) - tty->driver.minor_start); #endif save_flags(flags); cli(); info->xmit.head = info->xmit.tail = 0; restore_flags(flags); wake_up_interruptible(&tty->write_wait); if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup) (tty->ldisc.write_wakeup)(tty); } /* * This function is used to send a high-priority XON/XOFF character to * the device */ static void ambauart_send_xchar(struct tty_struct *tty, char ch) { struct amba_info *info = tty->driver_data; info->x_char = ch; if (ch) ambauart_enable_tx_interrupt(info); } static void ambauart_throttle(struct tty_struct *tty) { struct amba_info *info = tty->driver_data; unsigned long flags; if (I_IXOFF(tty)) ambauart_send_xchar(tty, STOP_CHAR(tty)); if (tty->termios->c_cflag & CRTSCTS) { save_flags(flags); cli(); info->mctrl &= ~TIOCM_RTS; info->port->set_mctrl(info->port, info->mctrl); restore_flags(flags); } } static void ambauart_unthrottle(struct tty_struct *tty) { struct amba_info *info = (struct amba_info *) tty->driver_data; unsigned long flags; if (I_IXOFF(tty)) { if (info->x_char) info->x_char = 0; else ambauart_send_xchar(tty, START_CHAR(tty)); } if (tty->termios->c_cflag & CRTSCTS) { save_flags(flags); cli(); info->mctrl |= TIOCM_RTS; info->port->set_mctrl(info->port, info->mctrl); restore_flags(flags); } } static int get_serial_info(struct amba_info *info, struct serial_struct *retinfo) { struct amba_state *state = info->state; struct amba_port *port = info->port; struct serial_struct tmp; memset(&tmp, 0, sizeof(tmp)); tmp.type = 0; tmp.line = state->line; tmp.port = port->uart_base; if (HIGH_BITS_OFFSET) tmp.port_high = port->uart_base >> HIGH_BITS_OFFSET; tmp.irq = port->irq; tmp.flags = 0; tmp.xmit_fifo_size = port->fifosize; tmp.baud_base = port->uartclk / 16; tmp.close_delay = state->close_delay; tmp.closing_wait = state->closing_wait; tmp.custom_divisor = state->custom_divisor; if (copy_to_user(retinfo, &tmp, sizeof(*retinfo))) return -EFAULT; return 0; } static int set_serial_info(struct amba_info *info, struct serial_struct *newinfo) { struct serial_struct new_serial; struct amba_state *state, old_state; struct amba_port *port; unsigned long new_port; unsigned int i, change_irq, change_port; int retval = 0; if (copy_from_user(&new_serial, newinfo, sizeof(new_serial))) return -EFAULT; state = info->state; old_state = *state; port = info->port; new_port = new_serial.port; if (HIGH_BITS_OFFSET) new_port += (unsigned long) new_serial.port_high << HIGH_BITS_OFFSET; change_irq = new_serial.irq != port->irq; change_port = new_port != port->uart_base; if (!capable(CAP_SYS_ADMIN)) { if (change_irq || change_port || (new_serial.baud_base != port->uartclk / 16) || (new_serial.close_delay != state->close_delay) || (new_serial.xmit_fifo_size != port->fifosize) || ((new_serial.flags & ~ASYNC_USR_MASK) != (state->flags & ~ASYNC_USR_MASK))) return -EPERM; state->flags = ((state->flags & ~ASYNC_USR_MASK) | (new_serial.flags & ASYNC_USR_MASK)); info->flags = ((info->flags & ~ASYNC_USR_MASK) | (new_serial.flags & ASYNC_USR_MASK)); state->custom_divisor = new_serial.custom_divisor; goto check_and_exit; } if ((new_serial.irq >= NR_IRQS) || (new_serial.irq < 0) || (new_serial.baud_base < 9600)) return -EINVAL; if (new_serial.type && change_port) { for (i = 0; i < SERIAL_AMBA_NR; i++) if ((port != amba_ports + i) && amba_ports[i].uart_base != new_port) return -EADDRINUSE; } if ((change_port || change_irq) && (state->count > 1)) return -EBUSY; /* * OK, past this point, all the error checking has been done. * At this point, we start making changes..... */ port->uartclk = new_serial.baud_base * 16; state->flags = ((state->flags & ~ASYNC_FLAGS) | (new_serial.flags & ASYNC_FLAGS)); info->flags = ((state->flags & ~ASYNC_INTERNAL_FLAGS) | (info->flags & ASYNC_INTERNAL_FLAGS)); state->custom_divisor = new_serial.custom_divisor; state->close_delay = new_serial.close_delay * HZ / 100; state->closing_wait = new_serial.closing_wait * HZ / 100; info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0; port->fifosize = new_serial.xmit_fifo_size; if (change_port || change_irq) { /* * We need to shutdown the serial port at the old * port/irq combination. */ ambauart_shutdown(info); port->irq = new_serial.irq; port->uart_base = new_port; } check_and_exit: if (!port->uart_base) return 0; if (info->flags & ASYNC_INITIALIZED) { if ((old_state.flags & ASYNC_SPD_MASK) != (state->flags & ASYNC_SPD_MASK) || (old_state.custom_divisor != state->custom_divisor)) { if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI) info->tty->alt_speed = 57600; if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI) info->tty->alt_speed = 115200; if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI) info->tty->alt_speed = 230400; if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP) info->tty->alt_speed = 460800; ambauart_change_speed(info, NULL); } } else retval = ambauart_startup(info); return retval; } /* * get_lsr_info - get line status register info */ static int get_lsr_info(struct amba_info *info, unsigned int *value) { unsigned int result, status; unsigned long flags; save_flags(flags); cli(); status = UART_GET_FR(info->port); restore_flags(flags); result = status & AMBA_UARTFR_BUSY ? TIOCSER_TEMT : 0; /* * If we're about to load something into the transmit * register, we'll pretend the transmitter isn't empty to * avoid a race condition (depending on when the transmit * interrupt happens). */ if (info->x_char || ((CIRC_CNT(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE) > 0) && !info->tty->stopped && !info->tty->hw_stopped)) result &= TIOCSER_TEMT; return put_user(result, value); } static int get_modem_info(struct amba_info *info, unsigned int *value) { unsigned int result = info->mctrl; unsigned int status; status = UART_GET_FR(info->port); if (status & AMBA_UARTFR_DCD) result |= TIOCM_CAR; if (status & AMBA_UARTFR_DSR) result |= TIOCM_DSR; if (status & AMBA_UARTFR_CTS) result |= TIOCM_CTS; return put_user(result, value); } static int set_modem_info(struct amba_info *info, unsigned int cmd, unsigned int *value) { unsigned int arg, old; unsigned long flags; if (get_user(arg, value)) return -EFAULT; old = info->mctrl; switch (cmd) { case TIOCMBIS: info->mctrl |= arg; break; case TIOCMBIC: info->mctrl &= ~arg; break; case TIOCMSET: info->mctrl = arg; break; default: return -EINVAL; } save_flags(flags); cli(); if (old != info->mctrl) info->port->set_mctrl(info->port, info->mctrl); restore_flags(flags); return 0; } static void ambauart_break_ctl(struct tty_struct *tty, int break_state) { struct amba_info *info = tty->driver_data; unsigned long flags; unsigned int lcr_h; save_flags(flags); cli(); lcr_h = UART_GET_LCRH(info->port); if (break_state == -1) lcr_h |= AMBA_UARTLCR_H_BRK; else lcr_h &= ~AMBA_UARTLCR_H_BRK; UART_PUT_LCRH(info->port, lcr_h); restore_flags(flags); } static int ambauart_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg) { struct amba_info *info = tty->driver_data; struct amba_icount cprev, cnow; struct serial_icounter_struct icount; unsigned long flags; if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) && (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) && (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) { if (tty->flags & (1 << TTY_IO_ERROR)) return -EIO; } switch (cmd) { case TIOCMGET: return get_modem_info(info, (unsigned int *)arg); case TIOCMBIS: case TIOCMBIC: case TIOCMSET: return set_modem_info(info, cmd, (unsigned int *)arg); case TIOCGSERIAL: return get_serial_info(info, (struct serial_struct *)arg); case TIOCSSERIAL: return set_serial_info(info, (struct serial_struct *)arg); case TIOCSERGETLSR: /* Get line status register */ return get_lsr_info(info, (unsigned int *)arg); /* * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change * - mask passed in arg for lines of interest * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking) * Caller should use TIOCGICOUNT to see which one it was */ case TIOCMIWAIT: save_flags(flags); cli(); /* note the counters on entry */ cprev = info->state->icount; /* Force modem status interrupts on */ UART_PUT_CR(info->port, UART_GET_CR(info->port) | AMBA_UARTCR_MSIE); restore_flags(flags); while (1) { interruptible_sleep_on(&info->delta_msr_wait); /* see if a signal did it */ if (signal_pending(current)) return -ERESTARTSYS; save_flags(flags); cli(); cnow = info->state->icount; /* atomic copy */ restore_flags(flags); if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) return -EIO; /* no change => error */ if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) || ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) || ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) || ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) { return 0; } cprev = cnow; } /* NOTREACHED */ /* * Get counter of input serial line interrupts (DCD,RI,DSR,CTS) * Return: write counters to the user passed counter struct * NB: both 1->0 and 0->1 transitions are counted except for * RI where only 0->1 is counted. */ case TIOCGICOUNT: save_flags(flags); cli(); cnow = info->state->icount; restore_flags(flags); icount.cts = cnow.cts; icount.dsr = cnow.dsr; icount.rng = cnow.rng; icount.dcd = cnow.dcd; icount.rx = cnow.rx; icount.tx = cnow.tx; icount.frame = cnow.frame; icount.overrun = cnow.overrun; icount.parity = cnow.parity; icount.brk = cnow.brk; icount.buf_overrun = cnow.buf_overrun; return copy_to_user((void *)arg, &icount, sizeof(icount)) ? -EFAULT : 0; default: return -ENOIOCTLCMD; } return 0; } static void ambauart_set_termios(struct tty_struct *tty, struct termios *old_termios) { struct amba_info *info = tty->driver_data; unsigned long flags; unsigned int cflag = tty->termios->c_cflag; if ((cflag ^ old_termios->c_cflag) == 0 && RELEVENT_IFLAG(tty->termios->c_iflag ^ old_termios->c_iflag) == 0) return; ambauart_change_speed(info, old_termios); /* Handle transition to B0 status */ if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD)) { save_flags(flags); cli(); info->mctrl &= ~(TIOCM_RTS | TIOCM_DTR); info->port->set_mctrl(info->port, info->mctrl); restore_flags(flags); } /* Handle transition away from B0 status */ if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) { save_flags(flags); cli(); info->mctrl |= TIOCM_DTR; if (!(cflag & CRTSCTS) || !test_bit(TTY_THROTTLED, &tty->flags)) info->mctrl |= TIOCM_RTS; info->port->set_mctrl(info->port, info->mctrl); restore_flags(flags); } /* Handle turning off CRTSCTS */ if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) { tty->hw_stopped = 0; ambauart_start(tty); } #if 0 /* * No need to wake up processes in open wait, since they * sample the CLOCAL flag once, and don't recheck it. * XXX It's not clear whether the current behavior is correct * or not. Hence, this may change..... */ if (!(old_termios->c_cflag & CLOCAL) && (tty->termios->c_cflag & CLOCAL)) wake_up_interruptible(&info->open_wait); #endif } static void ambauart_close(struct tty_struct *tty, struct file *filp) { struct amba_info *info = tty->driver_data; struct amba_state *state; unsigned long flags; if (!info) return; state = info->state; #if DEBUG printk("ambauart_close() called\n"); #endif save_flags(flags); cli(); if (tty_hung_up_p(filp)) { MOD_DEC_USE_COUNT; restore_flags(flags); return; } if ((tty->count == 1) && (state->count != 1)) { /* * Uh, oh. tty->count is 1, which means that the tty * structure will be freed. state->count should always * be one in these conditions. If it's greater than * one, we've got real problems, since it means the * serial port won't be shutdown. */ printk("ambauart_close: bad serial port count; tty->count is 1, " "state->count is %d\n", state->count); state->count = 1; } if (--state->count < 0) { printk("rs_close: bad serial port count for %s%d: %d\n", tty->driver.name, info->state->line, state->count); state->count = 0; } if (state->count) { MOD_DEC_USE_COUNT; restore_flags(flags); return; } info->flags |= ASYNC_CLOSING; restore_flags(flags); /* * Save the termios structure, since this port may have * separate termios for callout and dialin. */ if (info->flags & ASYNC_NORMAL_ACTIVE) info->state->normal_termios = *tty->termios; if (info->flags & ASYNC_CALLOUT_ACTIVE) info->state->callout_termios = *tty->termios; /* * Now we wait for the transmit buffer to clear; and we notify * the line discipline to only process XON/XOFF characters. */ tty->closing = 1; if (info->state->closing_wait != ASYNC_CLOSING_WAIT_NONE) tty_wait_until_sent(tty, info->state->closing_wait); /* * At this point, we stop accepting input. To do this, we * disable the receive line status interrupts. */ if (info->flags & ASYNC_INITIALIZED) { ambauart_disable_rx_interrupt(info); /* * Before we drop DTR, make sure the UART transmitter * has completely drained; this is especially * important if there is a transmit FIFO! */ ambauart_wait_until_sent(tty, info->timeout); } ambauart_shutdown(info); if (tty->driver.flush_buffer) tty->driver.flush_buffer(tty); if (tty->ldisc.flush_buffer) tty->ldisc.flush_buffer(tty); tty->closing = 0; info->event = 0; info->tty = NULL; if (info->blocked_open) { if (info->state->close_delay) { set_current_state(TASK_INTERRUPTIBLE); schedule_timeout(info->state->close_delay); } wake_up_interruptible(&info->open_wait); } info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE| ASYNC_CLOSING); wake_up_interruptible(&info->close_wait); MOD_DEC_USE_COUNT; } static void ambauart_wait_until_sent(struct tty_struct *tty, int timeout) { struct amba_info *info = (struct amba_info *) tty->driver_data; unsigned long char_time, expire; unsigned int status; if (info->port->fifosize == 0) return; /* * Set the check interval to be 1/5 of the estimated time to * send a single character, and make it at least 1. The check * interval should also be less than the timeout. * * Note: we have to use pretty tight timings here to satisfy * the NIST-PCTS. */ char_time = (info->timeout - HZ/50) / info->port->fifosize; char_time = char_time / 5; if (char_time == 0) char_time = 1; if (timeout && timeout < char_time) char_time = timeout; /* * If the transmitter hasn't cleared in twice the approximate * amount of time to send the entire FIFO, it probably won't * ever clear. This assumes the UART isn't doing flow * control, which is currently the case. Hence, if it ever * takes longer than info->timeout, this is probably due to a * UART bug of some kind. So, we clamp the timeout parameter at * 2*info->timeout. */ if (!timeout || timeout > 2 * info->timeout) timeout = 2 * info->timeout; expire = jiffies + timeout; #if DEBUG printk("ambauart_wait_until_sent(%d), jiff=%lu, expire=%lu...\n", MINOR(tty->device) - tty->driver.minor_start, jiffies, expire); #endif while (UART_GET_FR(info->port) & AMBA_UARTFR_BUSY) { set_current_state(TASK_INTERRUPTIBLE); schedule_timeout(char_time); if (signal_pending(current)) break; if (timeout && time_after(jiffies, expire)) break; status = UART_GET_FR(info->port); } set_current_state(TASK_RUNNING); } static void ambauart_hangup(struct tty_struct *tty) { struct amba_info *info = tty->driver_data; struct amba_state *state = info->state; ambauart_flush_buffer(tty); if (info->flags & ASYNC_CLOSING) return; ambauart_shutdown(info); info->event = 0; state->count = 0; info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE); info->tty = NULL; wake_up_interruptible(&info->open_wait); } static int block_til_ready(struct tty_struct *tty, struct file *filp, struct amba_info *info) { DECLARE_WAITQUEUE(wait, current); struct amba_state *state = info->state; unsigned long flags; int do_clocal = 0, extra_count = 0, retval; /* * If the device is in the middle of being closed, then block * until it's done, and then try again. */ if (tty_hung_up_p(filp) || (info->flags & ASYNC_CLOSING)) { if (info->flags & ASYNC_CLOSING) interruptible_sleep_on(&info->close_wait); return (info->flags & ASYNC_HUP_NOTIFY) ? -EAGAIN : -ERESTARTSYS; } /* * If this is a callout device, then just make sure the normal * device isn't being used. */ if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) { if (info->flags & ASYNC_NORMAL_ACTIVE) return -EBUSY; if ((info->flags & ASYNC_CALLOUT_ACTIVE) && (info->flags & ASYNC_SESSION_LOCKOUT) && (info->session != current->session)) return -EBUSY; if ((info->flags & ASYNC_CALLOUT_ACTIVE) && (info->flags & ASYNC_PGRP_LOCKOUT) && (info->pgrp != current->pgrp)) return -EBUSY; info->flags |= ASYNC_CALLOUT_ACTIVE; return 0; } /* * If non-blocking mode is set, or the port is not enabled, * then make the check up front and then exit. */ if ((filp->f_flags & O_NONBLOCK) || (tty->flags & (1 << TTY_IO_ERROR))) { if (info->flags & ASYNC_CALLOUT_ACTIVE) return -EBUSY; info->flags |= ASYNC_NORMAL_ACTIVE; return 0; } if (info->flags & ASYNC_CALLOUT_ACTIVE) { if (state->normal_termios.c_cflag & CLOCAL) do_clocal = 1; } else { if (tty->termios->c_cflag & CLOCAL) do_clocal = 1; } /* * Block waiting for the carrier detect and the line to become * free (i.e., not in use by the callout). While we are in * this loop, state->count is dropped by one, so that * rs_close() knows when to free things. We restore it upon * exit, either normal or abnormal. */ retval = 0; add_wait_queue(&info->open_wait, &wait); save_flags(flags); cli(); if (!tty_hung_up_p(filp)) { extra_count = 1; state->count--; } restore_flags(flags); info->blocked_open++; while (1) { save_flags(flags); cli(); if (!(info->flags & ASYNC_CALLOUT_ACTIVE) && (tty->termios->c_cflag & CBAUD)) { info->mctrl = TIOCM_DTR | TIOCM_RTS; info->port->set_mctrl(info->port, info->mctrl); } restore_flags(flags); set_current_state(TASK_INTERRUPTIBLE); if (tty_hung_up_p(filp) || !(info->flags & ASYNC_INITIALIZED)) { if (info->flags & ASYNC_HUP_NOTIFY) retval = -EAGAIN; else retval = -ERESTARTSYS; break; } if (!(info->flags & ASYNC_CALLOUT_ACTIVE) && !(info->flags & ASYNC_CLOSING) && (do_clocal || (UART_GET_FR(info->port) & AMBA_UARTFR_DCD))) break; if (signal_pending(current)) { retval = -ERESTARTSYS; break; } schedule(); } set_current_state(TASK_RUNNING); remove_wait_queue(&info->open_wait, &wait); if (extra_count) state->count++; info->blocked_open--; if (retval) return retval; info->flags |= ASYNC_NORMAL_ACTIVE; return 0; } static struct amba_info *ambauart_get(int line) { struct amba_info *info; struct amba_state *state = amba_state + line; state->count++; if (state->info) return state->info; info = kmalloc(sizeof(struct amba_info), GFP_KERNEL); if (info) { memset(info, 0, sizeof(struct amba_info)); init_waitqueue_head(&info->open_wait); init_waitqueue_head(&info->close_wait); init_waitqueue_head(&info->delta_msr_wait); info->flags = state->flags; info->state = state; info->port = amba_ports + line; tasklet_init(&info->tlet, ambauart_tasklet_action, (unsigned long)info); } if (state->info) { kfree(info); return state->info; } state->info = info; return info; } static int ambauart_open(struct tty_struct *tty, struct file *filp) { struct amba_info *info; int retval, line = MINOR(tty->device) - tty->driver.minor_start; #if DEBUG printk("ambauart_open(%d) called\n", line); #endif // is this a line that we've got? MOD_INC_USE_COUNT; if (line >= SERIAL_AMBA_NR) { MOD_DEC_USE_COUNT; return -ENODEV; } info = ambauart_get(line); if (!info) return -ENOMEM; tty->driver_data = info; info->tty = tty; info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0; /* * Make sure we have the temporary buffer allocated */ if (!tmp_buf) { unsigned long page = get_zeroed_page(GFP_KERNEL); if (tmp_buf) free_page(page); else if (!page) { MOD_DEC_USE_COUNT; return -ENOMEM; } tmp_buf = (u_char *)page; } /* * If the port is in the middle of closing, bail out now. */ if (tty_hung_up_p(filp) || (info->flags & ASYNC_CLOSING)) { if (info->flags & ASYNC_CLOSING) interruptible_sleep_on(&info->close_wait); MOD_DEC_USE_COUNT; return -EAGAIN; } /* * Start up the serial port */ retval = ambauart_startup(info); if (retval) { MOD_DEC_USE_COUNT; return retval; } retval = block_til_ready(tty, filp, info); if (retval) { MOD_DEC_USE_COUNT; return retval; } if ((info->state->count == 1) && (info->flags & ASYNC_SPLIT_TERMIOS)) { if (tty->driver.subtype == SERIAL_TYPE_NORMAL) *tty->termios = info->state->normal_termios; else *tty->termios = info->state->callout_termios; } #ifdef CONFIG_SERIAL_AMBA_CONSOLE if (ambauart_cons.cflag && ambauart_cons.index == line) { tty->termios->c_cflag = ambauart_cons.cflag; ambauart_cons.cflag = 0; } #endif ambauart_change_speed(info, NULL); info->session = current->session; info->pgrp = current->pgrp; return 0; } int __init ambauart_init(void) { int i; ambanormal_driver.magic = TTY_DRIVER_MAGIC; ambanormal_driver.driver_name = "serial_amba"; ambanormal_driver.name = SERIAL_AMBA_NAME; ambanormal_driver.major = SERIAL_AMBA_MAJOR; ambanormal_driver.minor_start = SERIAL_AMBA_MINOR; ambanormal_driver.num = SERIAL_AMBA_NR; ambanormal_driver.type = TTY_DRIVER_TYPE_SERIAL; ambanormal_driver.subtype = SERIAL_TYPE_NORMAL; ambanormal_driver.init_termios = tty_std_termios; ambanormal_driver.init_termios.c_cflag = B38400 | CS8 | CREAD | HUPCL | CLOCAL; ambanormal_driver.flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS; ambanormal_driver.refcount = &ambauart_refcount; ambanormal_driver.table = ambauart_table; ambanormal_driver.termios = ambauart_termios; ambanormal_driver.termios_locked = ambauart_termios_locked; ambanormal_driver.open = ambauart_open; ambanormal_driver.close = ambauart_close; ambanormal_driver.write = ambauart_write; ambanormal_driver.put_char = ambauart_put_char; ambanormal_driver.flush_chars = ambauart_flush_chars; ambanormal_driver.write_room = ambauart_write_room; ambanormal_driver.chars_in_buffer = ambauart_chars_in_buffer; ambanormal_driver.flush_buffer = ambauart_flush_buffer; ambanormal_driver.ioctl = ambauart_ioctl; ambanormal_driver.throttle = ambauart_throttle; ambanormal_driver.unthrottle = ambauart_unthrottle; ambanormal_driver.send_xchar = ambauart_send_xchar; ambanormal_driver.set_termios = ambauart_set_termios; ambanormal_driver.stop = ambauart_stop; ambanormal_driver.start = ambauart_start; ambanormal_driver.hangup = ambauart_hangup; ambanormal_driver.break_ctl = ambauart_break_ctl; ambanormal_driver.wait_until_sent = ambauart_wait_until_sent; ambanormal_driver.read_proc = NULL; /* * The callout device is just like the normal device except for * the major number and the subtype code. */ ambacallout_driver = ambanormal_driver; ambacallout_driver.name = CALLOUT_AMBA_NAME; ambacallout_driver.major = CALLOUT_AMBA_MAJOR; ambacallout_driver.subtype = SERIAL_TYPE_CALLOUT; ambacallout_driver.read_proc = NULL; ambacallout_driver.proc_entry = NULL; if (tty_register_driver(&ambanormal_driver)) panic("Couldn't register AMBA serial driver\n"); if (tty_register_driver(&ambacallout_driver)) panic("Couldn't register AMBA callout driver\n"); for (i = 0; i < SERIAL_AMBA_NR; i++) { struct amba_state *state = amba_state + i; state->line = i; state->close_delay = 5 * HZ / 10; state->closing_wait = 30 * HZ; state->callout_termios = ambacallout_driver.init_termios; state->normal_termios = ambanormal_driver.init_termios; } return 0; } __initcall(ambauart_init); #ifdef CONFIG_SERIAL_AMBA_CONSOLE /************** console driver *****************/ /* * This code is currently never used; console->read is never called. * Therefore, although we have an implementation, we don't use it. * FIXME: the "const char *s" should be fixed to "char *s" some day. * (when the definition in include/linux/console.h is also fixed) */ #ifdef used_and_not_const_char_pointer static int ambauart_console_read(struct console *co, const char *s, u_int count) { struct amba_port *port = &amba_ports[co->index]; unsigned int status; char *w; int c; #if DEBUG printk("ambauart_console_read() called\n"); #endif c = 0; w = s; while (c < count) { status = UART_GET_FR(port); if (UART_RX_DATA(status)) { *w++ = UART_GET_CHAR(port); c++; } else { // nothing more to get, return return c; } } // return the count return c; } #endif /* * Print a string to the serial port trying not to disturb * any possible real use of the port... * * The console must be locked when we get here. */ static void ambauart_console_write(struct console *co, const char *s, u_int count) { struct amba_port *port = &amba_ports[co->index]; unsigned int status, old_cr; int i; /* * First save the CR then disable the interrupts */ old_cr = UART_GET_CR(port); UART_PUT_CR(port, AMBA_UARTCR_UARTEN); /* * Now, do each character */ for (i = 0; i < count; i++) { do { status = UART_GET_FR(port); } while (!UART_TX_READY(status)); UART_PUT_CHAR(port, s[i]); if (s[i] == '\n') { do { status = UART_GET_FR(port); } while (!UART_TX_READY(status)); UART_PUT_CHAR(port, '\r'); } } /* * Finally, wait for transmitter to become empty * and restore the TCR */ do { status = UART_GET_FR(port); } while (status & AMBA_UARTFR_BUSY); UART_PUT_CR(port, old_cr); } static kdev_t ambauart_console_device(struct console *c) { return MKDEV(SERIAL_AMBA_MAJOR, SERIAL_AMBA_MINOR + c->index); } static int __init ambauart_console_setup(struct console *co, char *options) { struct amba_port *port; int baud = 38400; int bits = 8; int parity = 'n'; u_int cflag = CREAD | HUPCL | CLOCAL; u_int lcr_h, quot; if (co->index >= SERIAL_AMBA_NR) co->index = 0; port = &amba_ports[co->index]; if (options) { char *s = options; baud = simple_strtoul(s, NULL, 10); while (*s >= '0' && *s <= '9') s++; if (*s) parity = *s++; if (*s) bits = *s - '0'; } /* * Now construct a cflag setting. */ switch (baud) { case 1200: cflag |= B1200; break; case 2400: cflag |= B2400; break; case 4800: cflag |= B4800; break; default: cflag |= B9600; baud = 9600; break; case 19200: cflag |= B19200; break; case 38400: cflag |= B38400; break; case 57600: cflag |= B57600; break; case 115200: cflag |= B115200; break; } switch (bits) { case 7: cflag |= CS7; lcr_h = AMBA_UARTLCR_H_WLEN_7; break; default: cflag |= CS8; lcr_h = AMBA_UARTLCR_H_WLEN_8; break; } switch (parity) { case 'o': case 'O': cflag |= PARODD; lcr_h |= AMBA_UARTLCR_H_PEN; break; case 'e': case 'E': cflag |= PARENB; lcr_h |= AMBA_UARTLCR_H_PEN | AMBA_UARTLCR_H_EPS; break; } co->cflag = cflag; if (port->fifosize > 1) lcr_h |= AMBA_UARTLCR_H_FEN; quot = (port->uartclk / (16 * baud)) - 1; UART_PUT_LCRL(port, (quot & 0xff)); UART_PUT_LCRM(port, (quot >> 8)); UART_PUT_LCRH(port, lcr_h); /* we will enable the port as we need it */ UART_PUT_CR(port, 0); return 0; } static struct console ambauart_cons = { name: SERIAL_AMBA_NAME, write: ambauart_console_write, #ifdef used_and_not_const_char_pointer read: ambauart_console_read, #endif device: ambauart_console_device, setup: ambauart_console_setup, flags: CON_PRINTBUFFER, index: -1, }; void __init ambauart_console_init(void) { register_console(&ambauart_cons); } #endif /* CONFIG_SERIAL_AMBA_CONSOLE */ MODULE_LICENSE("GPL"); EXPORT_NO_SYMBOLS;