Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * sound/oss/uart401.c

 *

 * MPU-401 UART driver (formerly uart401_midi.c)

 *

 *

 * Copyright (C) by Hannu Savolainen 1993-1997

 *

 * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)

 * Version 2 (June 1991). See the "COPYING" file distributed with this software

 * for more info.

 *

 * Changes:

 *      Alan Cox                Reformatted, removed sound_mem usage, use normal Linux

 *                              interrupt allocation. Protect against bogus unload

 *                              Fixed to allow IRQ > 15

 *      Christoph Hellwig       Adapted to module_init/module_exit

 *      Arnaldo C. de Melo      got rid of check_region

 *

 * Status:

 *              Untested

 */

#include <linux/init.h>

#include <linux/interrupt.h>

#include <linux/module.h>

#include <linux/spinlock.h>

#include "sound_config.h"

#include "mpu401.h"

typedef struct uart401_devc

{

        int             base;

        int             irq;

        int            *osp;

        void            (*midi_input_intr) (int dev, unsigned char data);

        int             opened, disabled;

        volatile unsigned char input_byte;

        int             my_dev;

        int             share_irq;

        spinlock_t      lock;

}

uart401_devc;

#define DATAPORT   (devc->base)

#define COMDPORT   (devc->base+1)

#define STATPORT   (devc->base+1)

static int uart401_status(uart401_devc * devc)

{

        return inb(STATPORT);

}

#define input_avail(devc) (!(uart401_status(devc)&INPUT_AVAIL))

#define output_ready(devc)      (!(uart401_status(devc)&OUTPUT_READY))

static void uart401_cmd(uart401_devc * devc, unsigned char cmd)

{

        outb((cmd), COMDPORT);

}

static int uart401_read(uart401_devc * devc)

{

        return inb(DATAPORT);

}

static void uart401_write(uart401_devc * devc, unsigned char byte)

{

        outb((byte), DATAPORT);

}

#define OUTPUT_READY    0x40

#define INPUT_AVAIL     0x80

#define MPU_ACK         0xFE

#define MPU_RESET       0xFF

#define UART_MODE_ON    0x3F

static int      reset_uart401(uart401_devc * devc);

static void     enter_uart_mode(uart401_devc * devc);

static void uart401_input_loop(uart401_devc * devc)

{

        int work_limit=30000;

        while (input_avail(devc) && --work_limit)

        {

                unsigned char   c = uart401_read(devc);

                if (c == MPU_ACK)

                        devc->input_byte = c;

                else if (devc->opened & OPEN_READ && devc->midi_input_intr)

                        devc->midi_input_intr(devc->my_dev, c);

        }

        if(work_limit==0)

                printk(KERN_WARNING "Too much work in interrupt on uart401 (0x%X). UART jabbering ??\n", devc->base);

}

irqreturn_t uart401intr(int irq, void *dev_id)

{

        uart401_devc *devc = dev_id;

        if (devc == NULL)

        {

                printk(KERN_ERR "uart401: bad devc\n");

                return IRQ_NONE;

        }

        if (input_avail(devc))

                uart401_input_loop(devc);

        return IRQ_HANDLED;

}

static int

uart401_open(int dev, int mode,

             void            (*input) (int dev, unsigned char data),

             void            (*output) (int dev)

)

{

        uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;

        if (devc->opened)

                return -EBUSY;

        /* Flush the UART */

        while (input_avail(devc))

                uart401_read(devc);

        devc->midi_input_intr = input;

        devc->opened = mode;

        enter_uart_mode(devc);

        devc->disabled = 0;

        return 0;

}

static void uart401_close(int dev)

{

        uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;

        reset_uart401(devc);

        devc->opened = 0;

}

static int uart401_out(int dev, unsigned char midi_byte)

{

        int timeout;

        unsigned long flags;

        uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;

        if (devc->disabled)

                return 1;

        /*

         * Test for input since pending input seems to block the output.

         */

        spin_lock_irqsave(&devc->lock,flags);

        if (input_avail(devc))

                uart401_input_loop(devc);

        spin_unlock_irqrestore(&devc->lock,flags);

        /*

         * Sometimes it takes about 13000 loops before the output becomes ready

         * (After reset). Normally it takes just about 10 loops.

         */

        for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);

        if (!output_ready(devc))

        {

                  printk(KERN_WARNING "uart401: Timeout - Device not responding\n");

                  devc->disabled = 1;

                  reset_uart401(devc);

                  enter_uart_mode(devc);

                  return 1;

        }

        uart401_write(devc, midi_byte);

        return 1;

}

static inline int uart401_start_read(int dev)

{

        return 0;

}

static inline int uart401_end_read(int dev)

{

        return 0;

}

static inline void uart401_kick(int dev)

{

}

static inline int uart401_buffer_status(int dev)

{

        return 0;

}

#define MIDI_SYNTH_NAME "MPU-401 UART"

#define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT

#include "midi_synth.h"

static const struct midi_operations uart401_operations =

{

        .owner          = THIS_MODULE,

        .info           = {"MPU-401 (UART) MIDI", 0, 0, SNDCARD_MPU401},

        .converter      = &std_midi_synth,

        .in_info        = {0},

        .open           = uart401_open,

        .close          = uart401_close,

        .outputc        = uart401_out,

        .start_read     = uart401_start_read,

        .end_read       = uart401_end_read,

        .kick           = uart401_kick,

        .buffer_status  = uart401_buffer_status,

};

static void enter_uart_mode(uart401_devc * devc)

{

        int ok, timeout;

        unsigned long flags;

        spin_lock_irqsave(&devc->lock,flags);

        for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);

        devc->input_byte = 0;

        uart401_cmd(devc, UART_MODE_ON);

        ok = 0;

        for (timeout = 50000; timeout > 0 && !ok; timeout--)

                if (devc->input_byte == MPU_ACK)

                        ok = 1;

                else if (input_avail(devc))

                        if (uart401_read(devc) == MPU_ACK)

                                ok = 1;

        spin_unlock_irqrestore(&devc->lock,flags);

}

static int reset_uart401(uart401_devc * devc)

{

        int ok, timeout, n;

        /*

         * Send the RESET command. Try again if no success at the first time.

         */

        ok = 0;

        for (n = 0; n < 2 && !ok; n++)

        {

                for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);

                devc->input_byte = 0;

                uart401_cmd(devc, MPU_RESET);

                /*

                 * Wait at least 25 msec. This method is not accurate so let's make the

                 * loop bit longer. Cannot sleep since this is called during boot.

                 */

                for (timeout = 50000; timeout > 0 && !ok; timeout--)

                {

                        if (devc->input_byte == MPU_ACK)        /* Interrupt */

                                ok = 1;

                        else if (input_avail(devc))

                        {

                                if (uart401_read(devc) == MPU_ACK)

                                        ok = 1;

                        }

                }

        }

        if (ok)

        {

                DEB(printk("Reset UART401 OK\n"));

        }

        else

                DDB(printk("Reset UART401 failed - No hardware detected.\n"));

        if (ok)

                uart401_input_loop(devc);       /*

                                                 * Flush input before enabling interrupts

                                                 */

        return ok;

}

int probe_uart401(struct address_info *hw_config, struct module *owner)

{

        uart401_devc *devc;

        char *name = "MPU-401 (UART) MIDI";

        int ok = 0;

        unsigned long flags;

        DDB(printk("Entered probe_uart401()\n"));

        /* Default to "not found" */

        hw_config->slots[4] = -1;

        if (!request_region(hw_config->io_base, 4, "MPU-401 UART")) {

                printk(KERN_INFO "uart401: could not request_region(%d, 4)\n", hw_config->io_base);

                return 0;

        }

        devc = kmalloc(sizeof(uart401_devc), GFP_KERNEL);

        if (!devc) {

                printk(KERN_WARNING "uart401: Can't allocate memory\n");

                goto cleanup_region;

        }

        devc->base = hw_config->io_base;

        devc->irq = hw_config->irq;

        devc->osp = hw_config->osp;

        devc->midi_input_intr = NULL;

        devc->opened = 0;

        devc->input_byte = 0;

        devc->my_dev = 0;

        devc->share_irq = 0;

        spin_lock_init(&devc->lock);

        spin_lock_irqsave(&devc->lock,flags);

        ok = reset_uart401(devc);

        spin_unlock_irqrestore(&devc->lock,flags);

        if (!ok)

                goto cleanup_devc;

        if (hw_config->name)

                name = hw_config->name;

        if (devc->irq < 0) {

                devc->share_irq = 1;

                devc->irq *= -1;

        } else

                devc->share_irq = 0;

        if (!devc->share_irq)

                if (request_irq(devc->irq, uart401intr, 0, "MPU-401 UART", devc) < 0) {

                        printk(KERN_WARNING "uart401: Failed to allocate IRQ%d\n", devc->irq);

                        devc->share_irq = 1;

                }

        devc->my_dev = sound_alloc_mididev();

        enter_uart_mode(devc);

        if (devc->my_dev == -1) {

                printk(KERN_INFO "uart401: Too many midi devices detected\n");

                goto cleanup_irq;

        }

        conf_printf(name, hw_config);

        midi_devs[devc->my_dev] = kmalloc(sizeof(struct midi_operations), GFP_KERNEL);

        if (!midi_devs[devc->my_dev]) {

                printk(KERN_ERR "uart401: Failed to allocate memory\n");

                goto cleanup_unload_mididev;

        }

        memcpy(midi_devs[devc->my_dev], &uart401_operations, sizeof(struct midi_operations));

        if (owner)

                midi_devs[devc->my_dev]->owner = owner;

        midi_devs[devc->my_dev]->devc = devc;

        midi_devs[devc->my_dev]->converter = kmalloc(sizeof(struct synth_operations), GFP_KERNEL);

        if (!midi_devs[devc->my_dev]->converter) {

                printk(KERN_WARNING "uart401: Failed to allocate memory\n");

                goto cleanup_midi_devs;

        }

        memcpy(midi_devs[devc->my_dev]->converter, &std_midi_synth, sizeof(struct synth_operations));

        strcpy(midi_devs[devc->my_dev]->info.name, name);

        midi_devs[devc->my_dev]->converter->id = "UART401";

        midi_devs[devc->my_dev]->converter->midi_dev = devc->my_dev;

        if (owner)

                midi_devs[devc->my_dev]->converter->owner = owner;

        hw_config->slots[4] = devc->my_dev;

        sequencer_init();

        devc->opened = 0;

        return 1;

cleanup_midi_devs:

        kfree(midi_devs[devc->my_dev]);

cleanup_unload_mididev:

        sound_unload_mididev(devc->my_dev);

cleanup_irq:

        if (!devc->share_irq)

                free_irq(devc->irq, devc);

cleanup_devc:

        kfree(devc);

cleanup_region:

        release_region(hw_config->io_base, 4);

        return 0;

}

void unload_uart401(struct address_info *hw_config)

{

        uart401_devc *devc;

        int n=hw_config->slots[4];

        /* Not set up */

        if(n==-1 || midi_devs[n]==NULL)

                return;

        /* Not allocated (erm ??) */

        devc = midi_devs[hw_config->slots[4]]->devc;

        if (devc == NULL)

                return;

        reset_uart401(devc);

        release_region(hw_config->io_base, 4);

        if (!devc->share_irq)

                free_irq(devc->irq, devc);

        if (devc)

        {

                kfree(midi_devs[devc->my_dev]->converter);

                kfree(midi_devs[devc->my_dev]);

                kfree(devc);

                devc = NULL;

        }

        /* This kills midi_devs[x] */

        sound_unload_mididev(hw_config->slots[4]);

}

EXPORT_SYMBOL(probe_uart401);

EXPORT_SYMBOL(unload_uart401);

EXPORT_SYMBOL(uart401intr);

static struct address_info cfg_mpu;

static int io = -1;

static int irq = -1;

module_param(io, int, 0444);

module_param(irq, int, 0444);

static int __init init_uart401(void)

{

        cfg_mpu.irq = irq;

        cfg_mpu.io_base = io;

        /* Can be loaded either for module use or to provide functions

           to others */

        if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1) {

                printk(KERN_INFO "MPU-401 UART driver Copyright (C) Hannu Savolainen 1993-1997");

                if (!probe_uart401(&cfg_mpu, THIS_MODULE))

                        return -ENODEV;

        }

        return 0;

}

static void __exit cleanup_uart401(void)

{

        if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1)

                unload_uart401(&cfg_mpu);

}

module_init(init_uart401);

module_exit(cleanup_uart401);

#ifndef MODULE

static int __init setup_uart401(char *str)

{

        /* io, irq */

        int ints[3];

        str = get_options(str, ARRAY_SIZE(ints), ints);

        io = ints[1];

        irq = ints[2];

        return 1;

}

__setup("uart401=", setup_uart401);

#endif

MODULE_LICENSE("GPL");