Linux-2.6.12-rc2

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / sound / drivers / mpu401 / mpu401_uart.c

/*
 *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
 *  Routines for control of MPU-401 in UART mode
 *
 *  MPU-401 supports UART mode which is not capable generate transmit
 *  interrupts thus output is done via polling. Also, if irq < 0, then
 *  input is done also via polling. Do not expect good performance.
 *
 *
 *   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
 *
 *   13-03-2003:
 *      Added support for different kind of hardware I/O. Build in choices
 *      are port and mmio. For other kind of I/O, set mpu->read and
 *      mpu->write to your own I/O functions.
 *
 */

#include <sound/driver.h>
#include <asm/io.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <sound/core.h>
#include <sound/mpu401.h>

MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
MODULE_DESCRIPTION("Routines for control of MPU-401 in UART mode");
MODULE_LICENSE("GPL");

static void snd_mpu401_uart_input_read(mpu401_t * mpu);
static void snd_mpu401_uart_output_write(mpu401_t * mpu);

/*

 */

#define snd_mpu401_input_avail(mpu)     (!(mpu->read(mpu, MPU401C(mpu)) & 0x80))
#define snd_mpu401_output_ready(mpu)    (!(mpu->read(mpu, MPU401C(mpu)) & 0x40))

#define MPU401_RESET            0xff
#define MPU401_ENTER_UART       0x3f
#define MPU401_ACK              0xfe

/* Build in lowlevel io */
static void mpu401_write_port(mpu401_t *mpu, unsigned char data, unsigned long addr)
{
        outb(data, addr);
}

static unsigned char mpu401_read_port(mpu401_t *mpu, unsigned long addr)
{
        return inb(addr);
}

static void mpu401_write_mmio(mpu401_t *mpu, unsigned char data, unsigned long addr)
{
        writeb(data, (void __iomem *)addr);
}

static unsigned char mpu401_read_mmio(mpu401_t *mpu, unsigned long addr)
{
        return readb((void __iomem *)addr);
}
/*  */

static void snd_mpu401_uart_clear_rx(mpu401_t *mpu)
{
        int timeout = 100000;
        for (; timeout > 0 && snd_mpu401_input_avail(mpu); timeout--)
                mpu->read(mpu, MPU401D(mpu));
#ifdef CONFIG_SND_DEBUG
        if (timeout <= 0)
                snd_printk("cmd: clear rx timeout (status = 0x%x)\n", mpu->read(mpu, MPU401C(mpu)));
#endif
}

static void _snd_mpu401_uart_interrupt(mpu401_t *mpu)
{
        spin_lock(&mpu->input_lock);
        if (test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode)) {
                snd_mpu401_uart_input_read(mpu);
        } else {
                snd_mpu401_uart_clear_rx(mpu);
        }
        spin_unlock(&mpu->input_lock);
        /* ok. for better Tx performance try do some output when input is done */
        if (test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode) &&
            test_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode)) {
                spin_lock(&mpu->output_lock);
                snd_mpu401_uart_output_write(mpu);
                spin_unlock(&mpu->output_lock);
        }
}

/**
 * snd_mpu401_uart_interrupt - generic MPU401-UART interrupt handler
 * @irq: the irq number
 * @dev_id: mpu401 instance
 * @regs: the reigster
 *
 * Processes the interrupt for MPU401-UART i/o.
 */
irqreturn_t snd_mpu401_uart_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
        mpu401_t *mpu = dev_id;
        
        if (mpu == NULL)
                return IRQ_NONE;
        _snd_mpu401_uart_interrupt(mpu);
        return IRQ_HANDLED;
}

/*
 * timer callback
 * reprogram the timer and call the interrupt job
 */
static void snd_mpu401_uart_timer(unsigned long data)
{
        mpu401_t *mpu = (mpu401_t *)data;

        spin_lock(&mpu->timer_lock);
        /*mpu->mode |= MPU401_MODE_TIMER;*/
        mpu->timer.expires = 1 + jiffies;
        add_timer(&mpu->timer);
        spin_unlock(&mpu->timer_lock);
        if (mpu->rmidi)
                _snd_mpu401_uart_interrupt(mpu);
}

/*
 * initialize the timer callback if not programmed yet
 */
static void snd_mpu401_uart_add_timer (mpu401_t *mpu, int input)
{
        unsigned long flags;

        spin_lock_irqsave (&mpu->timer_lock, flags);
        if (mpu->timer_invoked == 0) {
                init_timer(&mpu->timer);
                mpu->timer.data = (unsigned long)mpu;
                mpu->timer.function = snd_mpu401_uart_timer;
                mpu->timer.expires = 1 + jiffies;
                add_timer(&mpu->timer);
        } 
        mpu->timer_invoked |= input ? MPU401_MODE_INPUT_TIMER : MPU401_MODE_OUTPUT_TIMER;
        spin_unlock_irqrestore (&mpu->timer_lock, flags);
}

/*
 * remove the timer callback if still active
 */
static void snd_mpu401_uart_remove_timer (mpu401_t *mpu, int input)
{
        unsigned long flags;

        spin_lock_irqsave (&mpu->timer_lock, flags);
        if (mpu->timer_invoked) {
                mpu->timer_invoked &= input ? ~MPU401_MODE_INPUT_TIMER : ~MPU401_MODE_OUTPUT_TIMER;
                if (! mpu->timer_invoked)
                        del_timer(&mpu->timer);
        }
        spin_unlock_irqrestore (&mpu->timer_lock, flags);
}

/*

 */

static void snd_mpu401_uart_cmd(mpu401_t * mpu, unsigned char cmd, int ack)
{
        unsigned long flags;
        int timeout, ok;

        spin_lock_irqsave(&mpu->input_lock, flags);
        if (mpu->hardware != MPU401_HW_TRID4DWAVE) {
                mpu->write(mpu, 0x00, MPU401D(mpu));
                /*snd_mpu401_uart_clear_rx(mpu);*/
        }
        /* ok. standard MPU-401 initialization */
        if (mpu->hardware != MPU401_HW_SB) {
                for (timeout = 1000; timeout > 0 && !snd_mpu401_output_ready(mpu); timeout--)
                        udelay(10);
#ifdef CONFIG_SND_DEBUG
                if (!timeout)
                        snd_printk("cmd: tx timeout (status = 0x%x)\n", mpu->read(mpu, MPU401C(mpu)));
#endif
        }
        mpu->write(mpu, cmd, MPU401C(mpu));
        if (ack) {
                ok = 0;
                timeout = 10000;
                while (!ok && timeout-- > 0) {
                        if (snd_mpu401_input_avail(mpu)) {
                                if (mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
                                        ok = 1;
                        }
                }
                if (!ok && mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
                        ok = 1;
        } else {
                ok = 1;
        }
        spin_unlock_irqrestore(&mpu->input_lock, flags);
        if (! ok)
                snd_printk("cmd: 0x%x failed at 0x%lx (status = 0x%x, data = 0x%x)\n", cmd, mpu->port, mpu->read(mpu, MPU401C(mpu)), mpu->read(mpu, MPU401D(mpu)));
        // snd_printk("cmd: 0x%x at 0x%lx (status = 0x%x, data = 0x%x)\n", cmd, mpu->port, mpu->read(mpu, MPU401C(mpu)), mpu->read(mpu, MPU401D(mpu)));
}

/*
 * input/output open/close - protected by open_mutex in rawmidi.c
 */
static int snd_mpu401_uart_input_open(snd_rawmidi_substream_t * substream)
{
        mpu401_t *mpu;
        int err;

        mpu = substream->rmidi->private_data;
        if (mpu->open_input && (err = mpu->open_input(mpu)) < 0)
                return err;
        if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode)) {
                snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1);
                snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 1);
        }
        mpu->substream_input = substream;
        set_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
        return 0;
}

static int snd_mpu401_uart_output_open(snd_rawmidi_substream_t * substream)
{
        mpu401_t *mpu;
        int err;

        mpu = substream->rmidi->private_data;
        if (mpu->open_output && (err = mpu->open_output(mpu)) < 0)
                return err;
        if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode)) {
                snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1);
                snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 1);
        }
        mpu->substream_output = substream;
        set_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
        return 0;
}

static int snd_mpu401_uart_input_close(snd_rawmidi_substream_t * substream)
{
        mpu401_t *mpu;

        mpu = substream->rmidi->private_data;
        clear_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
        mpu->substream_input = NULL;
        if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode))
                snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
        if (mpu->close_input)
                mpu->close_input(mpu);
        return 0;
}

static int snd_mpu401_uart_output_close(snd_rawmidi_substream_t * substream)
{
        mpu401_t *mpu;

        mpu = substream->rmidi->private_data;
        clear_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
        mpu->substream_output = NULL;
        if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode))
                snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
        if (mpu->close_output)
                mpu->close_output(mpu);
        return 0;
}

/*
 * trigger input callback
 */
static void snd_mpu401_uart_input_trigger(snd_rawmidi_substream_t * substream, int up)
{
        unsigned long flags;
        mpu401_t *mpu;
        int max = 64;

        mpu = substream->rmidi->private_data;
        if (up) {
                if (! test_and_set_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode)) {
                        /* first time - flush FIFO */
                        while (max-- > 0)
                                mpu->read(mpu, MPU401D(mpu));
                        if (mpu->irq < 0)
                                snd_mpu401_uart_add_timer(mpu, 1);
                }
                
                /* read data in advance */
                spin_lock_irqsave(&mpu->input_lock, flags);
                snd_mpu401_uart_input_read(mpu);
                spin_unlock_irqrestore(&mpu->input_lock, flags);
        } else {
                if (mpu->irq < 0)
                        snd_mpu401_uart_remove_timer(mpu, 1);
                clear_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode);
        }
}

/*
 * transfer input pending data
 * call with input_lock spinlock held
 */
static void snd_mpu401_uart_input_read(mpu401_t * mpu)
{
        int max = 128;
        unsigned char byte;

        while (max-- > 0) {
                if (snd_mpu401_input_avail(mpu)) {
                        byte = mpu->read(mpu, MPU401D(mpu));
                        if (test_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode))
                                snd_rawmidi_receive(mpu->substream_input, &byte, 1);
                } else {
                        break; /* input not available */
                }
        }
}

/*
 *  Tx FIFO sizes:
 *    CS4237B                   - 16 bytes
 *    AudioDrive ES1688         - 12 bytes
 *    S3 SonicVibes             -  8 bytes
 *    SoundBlaster AWE 64       -  2 bytes (ugly hardware)
 */

/*
 * write output pending bytes
 * call with output_lock spinlock held
 */
static void snd_mpu401_uart_output_write(mpu401_t * mpu)
{
        unsigned char byte;
        int max = 256, timeout;

        do {
                if (snd_rawmidi_transmit_peek(mpu->substream_output, &byte, 1) == 1) {
                        for (timeout = 100; timeout > 0; timeout--) {
                                if (snd_mpu401_output_ready(mpu)) {
                                        mpu->write(mpu, byte, MPU401D(mpu));
                                        snd_rawmidi_transmit_ack(mpu->substream_output, 1);
                                        break;
                                }
                        }
                        if (timeout == 0)
                                break;  /* Tx FIFO full - try again later */
                } else {
                        snd_mpu401_uart_remove_timer (mpu, 0);
                        break;  /* no other data - leave the tx loop */
                }
        } while (--max > 0);
}

/*
 * output trigger callback
 */
static void snd_mpu401_uart_output_trigger(snd_rawmidi_substream_t * substream, int up)
{
        unsigned long flags;
        mpu401_t *mpu;

        mpu = substream->rmidi->private_data;
        if (up) {
                set_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);

                /* try to add the timer at each output trigger,
                 * since the output timer might have been removed in
                 * snd_mpu401_uart_output_write().
                 */
                snd_mpu401_uart_add_timer(mpu, 0);

                /* output pending data */
                spin_lock_irqsave(&mpu->output_lock, flags);
                snd_mpu401_uart_output_write(mpu);
                spin_unlock_irqrestore(&mpu->output_lock, flags);
        } else {
                snd_mpu401_uart_remove_timer(mpu, 0);
                clear_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
        }
}

/*

 */

static snd_rawmidi_ops_t snd_mpu401_uart_output =
{
        .open =         snd_mpu401_uart_output_open,
        .close =        snd_mpu401_uart_output_close,
        .trigger =      snd_mpu401_uart_output_trigger,
};

static snd_rawmidi_ops_t snd_mpu401_uart_input =
{
        .open =         snd_mpu401_uart_input_open,
        .close =        snd_mpu401_uart_input_close,
        .trigger =      snd_mpu401_uart_input_trigger,
};

static void snd_mpu401_uart_free(snd_rawmidi_t *rmidi)
{
        mpu401_t *mpu = rmidi->private_data;
        if (mpu->irq_flags && mpu->irq >= 0)
                free_irq(mpu->irq, (void *) mpu);
        if (mpu->res) {
                release_resource(mpu->res);
                kfree_nocheck(mpu->res);
        }
        kfree(mpu);
}

/**
 * snd_mpu401_uart_new - create an MPU401-UART instance
 * @card: the card instance
 * @device: the device index, zero-based
 * @hardware: the hardware type, MPU401_HW_XXXX
 * @port: the base address of MPU401 port
 * @integrated: non-zero if the port was already reserved by the chip
 * @irq: the irq number, -1 if no interrupt for mpu
 * @irq_flags: the irq request flags (SA_XXX), 0 if irq was already reserved.
 * @rrawmidi: the pointer to store the new rawmidi instance
 *
 * Creates a new MPU-401 instance.
 *
 * Note that the rawmidi instance is returned on the rrawmidi argument,
 * not the mpu401 instance itself.  To access to the mpu401 instance,
 * cast from rawmidi->private_data (with mpu401_t magic-cast).
 *
 * Returns zero if successful, or a negative error code.
 */
int snd_mpu401_uart_new(snd_card_t * card, int device,
                        unsigned short hardware,
                        unsigned long port, int integrated,
                        int irq, int irq_flags,
                        snd_rawmidi_t ** rrawmidi)
{
        mpu401_t *mpu;
        snd_rawmidi_t *rmidi;
        int err;

        if (rrawmidi)
                *rrawmidi = NULL;
        if ((err = snd_rawmidi_new(card, "MPU-401U", device, 1, 1, &rmidi)) < 0)
                return err;
        mpu = kcalloc(1, sizeof(*mpu), GFP_KERNEL);
        if (mpu == NULL) {
                snd_device_free(card, rmidi);
                return -ENOMEM;
        }
        rmidi->private_data = mpu;
        rmidi->private_free = snd_mpu401_uart_free;
        spin_lock_init(&mpu->input_lock);
        spin_lock_init(&mpu->output_lock);
        spin_lock_init(&mpu->timer_lock);
        mpu->hardware = hardware;
        if (!integrated) {
                int res_size = hardware == MPU401_HW_PC98II ? 4 : 2;
                if ((mpu->res = request_region(port, res_size, "MPU401 UART")) == NULL) {
                        snd_printk(KERN_ERR "mpu401_uart: unable to grab port 0x%lx size %d\n", port, res_size);
                        snd_device_free(card, rmidi);
                        return -EBUSY;
                }
        }
        switch (hardware) {
        case MPU401_HW_AUREAL:
                mpu->write = mpu401_write_mmio;
                mpu->read = mpu401_read_mmio;
                break;
        default:
                mpu->write = mpu401_write_port;
                mpu->read = mpu401_read_port;
                break;
        }
        mpu->port = port;
        if (hardware == MPU401_HW_PC98II)
                mpu->cport = port + 2;
        else
                mpu->cport = port + 1;
        if (irq >= 0 && irq_flags) {
                if (request_irq(irq, snd_mpu401_uart_interrupt, irq_flags, "MPU401 UART", (void *) mpu)) {
                        snd_printk(KERN_ERR "mpu401_uart: unable to grab IRQ %d\n", irq);
                        snd_device_free(card, rmidi);
                        return -EBUSY;
                }
        }
        mpu->irq = irq;
        mpu->irq_flags = irq_flags;
        if (card->shortname[0])
                snprintf(rmidi->name, sizeof(rmidi->name), "%s MIDI", card->shortname);
        else
                sprintf(rmidi->name, "MPU-401 MIDI %d-%d", card->number, device);
        snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_mpu401_uart_output);
        snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_mpu401_uart_input);
        rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
                             SNDRV_RAWMIDI_INFO_INPUT |
                             SNDRV_RAWMIDI_INFO_DUPLEX;
        mpu->rmidi = rmidi;
        if (rrawmidi)
                *rrawmidi = rmidi;
        return 0;
}

EXPORT_SYMBOL(snd_mpu401_uart_interrupt);
EXPORT_SYMBOL(snd_mpu401_uart_new);

/*
 *  INIT part
 */

static int __init alsa_mpu401_uart_init(void)
{
        return 0;
}

static void __exit alsa_mpu401_uart_exit(void)
{
}

module_init(alsa_mpu401_uart_init)
module_exit(alsa_mpu401_uart_exit)