https://github.com/torvalds/linux
Tip revision: 2ea659a9ef488125eb46da6eb571de5eae5c43f6 authored by Linus Torvalds on 13 May 2017, 20:19:49 UTC
Linux 4.12-rc1
Linux 4.12-rc1
Tip revision: 2ea659a
uart6850.c
/*
* sound/oss/uart6850.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.
* Extended by Alan Cox for Red Hat Software. Now a loadable MIDI driver.
* 28/4/97 - (C) Copyright Alan Cox. Released under the GPL version 2.
*
* Alan Cox: Updated for new modular code. Removed snd_* irq handling. Now
* uses native linux resources
* Christoph Hellwig: Adapted to module_init/module_exit
* Jeff Garzik: Made it work again, in theory
* FIXME: If the request_irq() succeeds, the probe succeeds. Ug.
*
* Status: Testing required (no shit -jgarzik)
*
*
*/
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/spinlock.h>
/* Mon Nov 22 22:38:35 MET 1993 marco@driq.home.usn.nl:
* added 6850 support, used with COVOX SoundMaster II and custom cards.
*/
#include "sound_config.h"
static int uart6850_base = 0x330;
static int *uart6850_osp;
#define DATAPORT (uart6850_base)
#define COMDPORT (uart6850_base+1)
#define STATPORT (uart6850_base+1)
static int uart6850_status(void)
{
return inb(STATPORT);
}
#define input_avail() (uart6850_status()&INPUT_AVAIL)
#define output_ready() (uart6850_status()&OUTPUT_READY)
static void uart6850_cmd(unsigned char cmd)
{
outb(cmd, COMDPORT);
}
static int uart6850_read(void)
{
return inb(DATAPORT);
}
static void uart6850_write(unsigned char byte)
{
outb(byte, DATAPORT);
}
#define OUTPUT_READY 0x02 /* Mask for data ready Bit */
#define INPUT_AVAIL 0x01 /* Mask for Data Send Ready Bit */
#define UART_RESET 0x95
#define UART_MODE_ON 0x03
static int uart6850_opened;
static int uart6850_irq;
static int uart6850_detected;
static int my_dev;
static DEFINE_SPINLOCK(lock);
static void (*midi_input_intr) (int dev, unsigned char data);
static void poll_uart6850(unsigned long dummy);
static DEFINE_TIMER(uart6850_timer, poll_uart6850, 0, 0);
static void uart6850_input_loop(void)
{
int count = 10;
while (count)
{
/*
* Not timed out
*/
if (input_avail())
{
unsigned char c = uart6850_read();
count = 100;
if (uart6850_opened & OPEN_READ)
midi_input_intr(my_dev, c);
}
else
{
while (!input_avail() && count)
count--;
}
}
}
static irqreturn_t m6850intr(int irq, void *dev_id)
{
if (input_avail())
uart6850_input_loop();
return IRQ_HANDLED;
}
/*
* It looks like there is no input interrupts in the UART mode. Let's try
* polling.
*/
static void poll_uart6850(unsigned long dummy)
{
unsigned long flags;
if (!(uart6850_opened & OPEN_READ))
return; /* Device has been closed */
spin_lock_irqsave(&lock,flags);
if (input_avail())
uart6850_input_loop();
uart6850_timer.expires = 1 + jiffies;
add_timer(&uart6850_timer);
/*
* Come back later
*/
spin_unlock_irqrestore(&lock,flags);
}
static int uart6850_open(int dev, int mode,
void (*input) (int dev, unsigned char data),
void (*output) (int dev)
)
{
if (uart6850_opened)
{
/* printk("Midi6850: Midi busy\n");*/
return -EBUSY;
}
uart6850_cmd(UART_RESET);
uart6850_input_loop();
midi_input_intr = input;
uart6850_opened = mode;
poll_uart6850(0); /*
* Enable input polling
*/
return 0;
}
static void uart6850_close(int dev)
{
uart6850_cmd(UART_MODE_ON);
del_timer(&uart6850_timer);
uart6850_opened = 0;
}
static int uart6850_out(int dev, unsigned char midi_byte)
{
int timeout;
unsigned long flags;
/*
* Test for input since pending input seems to block the output.
*/
spin_lock_irqsave(&lock,flags);
if (input_avail())
uart6850_input_loop();
spin_unlock_irqrestore(&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(); timeout--); /*
* Wait
*/
if (!output_ready())
{
printk(KERN_WARNING "Midi6850: Timeout\n");
return 0;
}
uart6850_write(midi_byte);
return 1;
}
static inline int uart6850_command(int dev, unsigned char *midi_byte)
{
return 1;
}
static inline int uart6850_start_read(int dev)
{
return 0;
}
static inline int uart6850_end_read(int dev)
{
return 0;
}
static inline void uart6850_kick(int dev)
{
}
static inline int uart6850_buffer_status(int dev)
{
return 0; /*
* No data in buffers
*/
}
#define MIDI_SYNTH_NAME "6850 UART Midi"
#define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
#include "midi_synth.h"
static struct midi_operations uart6850_operations =
{
.owner = THIS_MODULE,
.info = {"6850 UART", 0, 0, SNDCARD_UART6850},
.converter = &std_midi_synth,
.in_info = {0},
.open = uart6850_open,
.close = uart6850_close,
.outputc = uart6850_out,
.start_read = uart6850_start_read,
.end_read = uart6850_end_read,
.kick = uart6850_kick,
.command = uart6850_command,
.buffer_status = uart6850_buffer_status
};
static void __init attach_uart6850(struct address_info *hw_config)
{
int ok, timeout;
unsigned long flags;
if (!uart6850_detected)
return;
if ((my_dev = sound_alloc_mididev()) == -1)
{
printk(KERN_INFO "uart6850: Too many midi devices detected\n");
return;
}
uart6850_base = hw_config->io_base;
uart6850_osp = hw_config->osp;
uart6850_irq = hw_config->irq;
spin_lock_irqsave(&lock,flags);
for (timeout = 30000; timeout > 0 && !output_ready(); timeout--); /*
* Wait
*/
uart6850_cmd(UART_MODE_ON);
ok = 1;
spin_unlock_irqrestore(&lock,flags);
conf_printf("6850 Midi Interface", hw_config);
std_midi_synth.midi_dev = my_dev;
hw_config->slots[4] = my_dev;
midi_devs[my_dev] = &uart6850_operations;
sequencer_init();
}
static inline int reset_uart6850(void)
{
uart6850_read();
return 1; /*
* OK
*/
}
static int __init probe_uart6850(struct address_info *hw_config)
{
int ok;
uart6850_osp = hw_config->osp;
uart6850_base = hw_config->io_base;
uart6850_irq = hw_config->irq;
if (request_irq(uart6850_irq, m6850intr, 0, "MIDI6850", NULL) < 0)
return 0;
ok = reset_uart6850();
uart6850_detected = ok;
return ok;
}
static void __exit unload_uart6850(struct address_info *hw_config)
{
free_irq(hw_config->irq, NULL);
sound_unload_mididev(hw_config->slots[4]);
}
static struct address_info cfg_mpu;
static int __initdata io = -1;
static int __initdata irq = -1;
module_param_hw(io, int, ioport, 0);
module_param_hw(irq, int, irq, 0);
static int __init init_uart6850(void)
{
cfg_mpu.io_base = io;
cfg_mpu.irq = irq;
if (cfg_mpu.io_base == -1 || cfg_mpu.irq == -1) {
printk(KERN_INFO "uart6850: irq and io must be set.\n");
return -EINVAL;
}
if (probe_uart6850(&cfg_mpu))
return -ENODEV;
attach_uart6850(&cfg_mpu);
return 0;
}
static void __exit cleanup_uart6850(void)
{
unload_uart6850(&cfg_mpu);
}
module_init(init_uart6850);
module_exit(cleanup_uart6850);
#ifndef MODULE
static int __init setup_uart6850(char *str)
{
/* io, irq */
int ints[3];
str = get_options(str, ARRAY_SIZE(ints), ints);
io = ints[1];
irq = ints[2];
return 1;
}
__setup("uart6850=", setup_uart6850);
#endif
MODULE_LICENSE("GPL");