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/*
* Copyright (c) by Jaroslav Kysela <perex@perex.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. Without interrupt,
* 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 <linux/io.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <sound/core.h>
#include <sound/mpu401.h>
MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
MODULE_DESCRIPTION("Routines for control of MPU-401 in UART mode");
MODULE_LICENSE("GPL");
static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu);
static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu);
/*
*/
#define snd_mpu401_input_avail(mpu) \
(!(mpu->read(mpu, MPU401C(mpu)) & MPU401_RX_EMPTY))
#define snd_mpu401_output_ready(mpu) \
(!(mpu->read(mpu, MPU401C(mpu)) & MPU401_TX_FULL))
/* Build in lowlevel io */
static void mpu401_write_port(struct snd_mpu401 *mpu, unsigned char data,
unsigned long addr)
{
outb(data, addr);
}
static unsigned char mpu401_read_port(struct snd_mpu401 *mpu,
unsigned long addr)
{
return inb(addr);
}
static void mpu401_write_mmio(struct snd_mpu401 *mpu, unsigned char data,
unsigned long addr)
{
writeb(data, (void __iomem *)addr);
}
static unsigned char mpu401_read_mmio(struct snd_mpu401 *mpu,
unsigned long addr)
{
return readb((void __iomem *)addr);
}
/* */
static void snd_mpu401_uart_clear_rx(struct snd_mpu401 *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(KERN_ERR "cmd: clear rx timeout (status = 0x%x)\n",
mpu->read(mpu, MPU401C(mpu)));
#endif
}
static void uart_interrupt_tx(struct snd_mpu401 *mpu)
{
unsigned long flags;
if (test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode) &&
test_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode)) {
spin_lock_irqsave(&mpu->output_lock, flags);
snd_mpu401_uart_output_write(mpu);
spin_unlock_irqrestore(&mpu->output_lock, flags);
}
}
static void _snd_mpu401_uart_interrupt(struct snd_mpu401 *mpu)
{
unsigned long flags;
if (mpu->info_flags & MPU401_INFO_INPUT) {
spin_lock_irqsave(&mpu->input_lock, flags);
if (test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode))
snd_mpu401_uart_input_read(mpu);
else
snd_mpu401_uart_clear_rx(mpu);
spin_unlock_irqrestore(&mpu->input_lock, flags);
}
if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
/* ok. for better Tx performance try do some output
when input is done */
uart_interrupt_tx(mpu);
}
/**
* snd_mpu401_uart_interrupt - generic MPU401-UART interrupt handler
* @irq: the irq number
* @dev_id: mpu401 instance
*
* Processes the interrupt for MPU401-UART i/o.
*
* Return: %IRQ_HANDLED if the interrupt was handled. %IRQ_NONE otherwise.
*/
irqreturn_t snd_mpu401_uart_interrupt(int irq, void *dev_id)
{
struct snd_mpu401 *mpu = dev_id;
if (!mpu)
return IRQ_NONE;
_snd_mpu401_uart_interrupt(mpu);
return IRQ_HANDLED;
}
EXPORT_SYMBOL(snd_mpu401_uart_interrupt);
/**
* snd_mpu401_uart_interrupt_tx - generic MPU401-UART transmit irq handler
* @irq: the irq number
* @dev_id: mpu401 instance
*
* Processes the interrupt for MPU401-UART output.
*
* Return: %IRQ_HANDLED if the interrupt was handled. %IRQ_NONE otherwise.
*/
irqreturn_t snd_mpu401_uart_interrupt_tx(int irq, void *dev_id)
{
struct snd_mpu401 *mpu = dev_id;
if (!mpu)
return IRQ_NONE;
uart_interrupt_tx(mpu);
return IRQ_HANDLED;
}
EXPORT_SYMBOL(snd_mpu401_uart_interrupt_tx);
/*
* timer callback
* reprogram the timer and call the interrupt job
*/
static void snd_mpu401_uart_timer(struct timer_list *t)
{
struct snd_mpu401 *mpu = from_timer(mpu, t, timer);
unsigned long flags;
spin_lock_irqsave(&mpu->timer_lock, flags);
/*mpu->mode |= MPU401_MODE_TIMER;*/
mod_timer(&mpu->timer, 1 + jiffies);
spin_unlock_irqrestore(&mpu->timer_lock, flags);
if (mpu->rmidi)
_snd_mpu401_uart_interrupt(mpu);
}
/*
* initialize the timer callback if not programmed yet
*/
static void snd_mpu401_uart_add_timer (struct snd_mpu401 *mpu, int input)
{
unsigned long flags;
spin_lock_irqsave (&mpu->timer_lock, flags);
if (mpu->timer_invoked == 0) {
timer_setup(&mpu->timer, snd_mpu401_uart_timer, 0);
mod_timer(&mpu->timer, 1 + jiffies);
}
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 (struct snd_mpu401 *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);
}
/*
* send a UART command
* return zero if successful, non-zero for some errors
*/
static int snd_mpu401_uart_cmd(struct snd_mpu401 * 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(KERN_ERR "cmd: tx timeout (status = 0x%x)\n",
mpu->read(mpu, MPU401C(mpu)));
#endif
}
mpu->write(mpu, cmd, MPU401C(mpu));
if (ack && !(mpu->info_flags & MPU401_INFO_NO_ACK)) {
ok = 0;
timeout = 10000;
while (!ok && timeout-- > 0) {
if (snd_mpu401_input_avail(mpu
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