4 * MPU-401 UART driver (formerly uart401_midi.c)
7 * Copyright (C) by Hannu Savolainen 1993-1997
9 * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
10 * Version 2 (June 1991). See the "COPYING" file distributed with this software
14 * Alan Cox Reformatted, removed sound_mem usage, use normal Linux
15 * interrupt allocation. Protect against bogus unload
16 * Fixed to allow IRQ > 15
17 * Christoph Hellwig Adapted to module_init/module_exit
18 * Arnaldo C. de Melo got rid of check_region
24 #include <linux/init.h>
25 #include <linux/interrupt.h>
26 #include <linux/module.h>
27 #include <linux/spinlock.h>
28 #include "sound_config.h"
32 typedef struct uart401_devc
37 void (*midi_input_intr) (int dev, unsigned char data);
39 volatile unsigned char input_byte;
46 #define DATAPORT (devc->base)
47 #define COMDPORT (devc->base+1)
48 #define STATPORT (devc->base+1)
50 static int uart401_status(uart401_devc * devc)
55 #define input_avail(devc) (!(uart401_status(devc)&INPUT_AVAIL))
56 #define output_ready(devc) (!(uart401_status(devc)&OUTPUT_READY))
58 static void uart401_cmd(uart401_devc * devc, unsigned char cmd)
60 outb((cmd), COMDPORT);
63 static int uart401_read(uart401_devc * devc)
68 static void uart401_write(uart401_devc * devc, unsigned char byte)
70 outb((byte), DATAPORT);
73 #define OUTPUT_READY 0x40
74 #define INPUT_AVAIL 0x80
76 #define MPU_RESET 0xFF
77 #define UART_MODE_ON 0x3F
79 static int reset_uart401(uart401_devc * devc);
80 static void enter_uart_mode(uart401_devc * devc);
82 static void uart401_input_loop(uart401_devc * devc)
86 while (input_avail(devc) && --work_limit)
88 unsigned char c = uart401_read(devc);
92 else if (devc->opened & OPEN_READ && devc->midi_input_intr)
93 devc->midi_input_intr(devc->my_dev, c);
96 printk(KERN_WARNING "Too much work in interrupt on uart401 (0x%X). UART jabbering ??\n", devc->base);
99 irqreturn_t uart401intr(int irq, void *dev_id)
101 uart401_devc *devc = dev_id;
105 printk(KERN_ERR "uart401: bad devc\n");
109 if (input_avail(devc))
110 uart401_input_loop(devc);
115 uart401_open(int dev, int mode,
116 void (*input) (int dev, unsigned char data),
117 void (*output) (int dev)
120 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
127 while (input_avail(devc))
130 devc->midi_input_intr = input;
132 enter_uart_mode(devc);
138 static void uart401_close(int dev)
140 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
146 static int uart401_out(int dev, unsigned char midi_byte)
150 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
155 * Test for input since pending input seems to block the output.
158 spin_lock_irqsave(&devc->lock,flags);
159 if (input_avail(devc))
160 uart401_input_loop(devc);
162 spin_unlock_irqrestore(&devc->lock,flags);
165 * Sometimes it takes about 13000 loops before the output becomes ready
166 * (After reset). Normally it takes just about 10 loops.
169 for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
171 if (!output_ready(devc))
173 printk(KERN_WARNING "uart401: Timeout - Device not responding\n");
176 enter_uart_mode(devc);
179 uart401_write(devc, midi_byte);
183 static inline int uart401_start_read(int dev)
188 static inline int uart401_end_read(int dev)
193 static inline void uart401_kick(int dev)
197 static inline int uart401_buffer_status(int dev)
202 #define MIDI_SYNTH_NAME "MPU-401 UART"
203 #define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
204 #include "midi_synth.h"
206 static const struct midi_operations uart401_operations =
208 .owner = THIS_MODULE,
209 .info = {"MPU-401 (UART) MIDI", 0, 0, SNDCARD_MPU401},
210 .converter = &std_midi_synth,
212 .open = uart401_open,
213 .close = uart401_close,
214 .outputc = uart401_out,
215 .start_read = uart401_start_read,
216 .end_read = uart401_end_read,
217 .kick = uart401_kick,
218 .buffer_status = uart401_buffer_status,
221 static void enter_uart_mode(uart401_devc * devc)
226 spin_lock_irqsave(&devc->lock,flags);
227 for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
229 devc->input_byte = 0;
230 uart401_cmd(devc, UART_MODE_ON);
233 for (timeout = 50000; timeout > 0 && !ok; timeout--)
234 if (devc->input_byte == MPU_ACK)
236 else if (input_avail(devc))
237 if (uart401_read(devc) == MPU_ACK)
240 spin_unlock_irqrestore(&devc->lock,flags);
243 static int reset_uart401(uart401_devc * devc)
248 * Send the RESET command. Try again if no success at the first time.
253 for (n = 0; n < 2 && !ok; n++)
255 for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
256 devc->input_byte = 0;
257 uart401_cmd(devc, MPU_RESET);
260 * Wait at least 25 msec. This method is not accurate so let's make the
261 * loop bit longer. Cannot sleep since this is called during boot.
264 for (timeout = 50000; timeout > 0 && !ok; timeout--)
266 if (devc->input_byte == MPU_ACK) /* Interrupt */
268 else if (input_avail(devc))
270 if (uart401_read(devc) == MPU_ACK)
279 DEB(printk("Reset UART401 OK\n"));
282 DDB(printk("Reset UART401 failed - No hardware detected.\n"));
285 uart401_input_loop(devc); /*
286 * Flush input before enabling interrupts
292 int probe_uart401(struct address_info *hw_config, struct module *owner)
295 char *name = "MPU-401 (UART) MIDI";
299 DDB(printk("Entered probe_uart401()\n"));
301 /* Default to "not found" */
302 hw_config->slots[4] = -1;
304 if (!request_region(hw_config->io_base, 4, "MPU-401 UART")) {
305 printk(KERN_INFO "uart401: could not request_region(%d, 4)\n", hw_config->io_base);
309 devc = kmalloc(sizeof(uart401_devc), GFP_KERNEL);
311 printk(KERN_WARNING "uart401: Can't allocate memory\n");
315 devc->base = hw_config->io_base;
316 devc->irq = hw_config->irq;
317 devc->osp = hw_config->osp;
318 devc->midi_input_intr = NULL;
320 devc->input_byte = 0;
323 spin_lock_init(&devc->lock);
325 spin_lock_irqsave(&devc->lock,flags);
326 ok = reset_uart401(devc);
327 spin_unlock_irqrestore(&devc->lock,flags);
333 name = hw_config->name;
341 if (!devc->share_irq)
342 if (request_irq(devc->irq, uart401intr, 0, "MPU-401 UART", devc) < 0) {
343 printk(KERN_WARNING "uart401: Failed to allocate IRQ%d\n", devc->irq);
346 devc->my_dev = sound_alloc_mididev();
347 enter_uart_mode(devc);
349 if (devc->my_dev == -1) {
350 printk(KERN_INFO "uart401: Too many midi devices detected\n");
353 conf_printf(name, hw_config);
354 midi_devs[devc->my_dev] = kmalloc(sizeof(struct midi_operations), GFP_KERNEL);
355 if (!midi_devs[devc->my_dev]) {
356 printk(KERN_ERR "uart401: Failed to allocate memory\n");
357 goto cleanup_unload_mididev;
359 memcpy(midi_devs[devc->my_dev], &uart401_operations, sizeof(struct midi_operations));
362 midi_devs[devc->my_dev]->owner = owner;
364 midi_devs[devc->my_dev]->devc = devc;
365 midi_devs[devc->my_dev]->converter = kmalloc(sizeof(struct synth_operations), GFP_KERNEL);
366 if (!midi_devs[devc->my_dev]->converter) {
367 printk(KERN_WARNING "uart401: Failed to allocate memory\n");
368 goto cleanup_midi_devs;
370 memcpy(midi_devs[devc->my_dev]->converter, &std_midi_synth, sizeof(struct synth_operations));
371 strcpy(midi_devs[devc->my_dev]->info.name, name);
372 midi_devs[devc->my_dev]->converter->id = "UART401";
373 midi_devs[devc->my_dev]->converter->midi_dev = devc->my_dev;
376 midi_devs[devc->my_dev]->converter->owner = owner;
378 hw_config->slots[4] = devc->my_dev;
383 kfree(midi_devs[devc->my_dev]);
384 cleanup_unload_mididev:
385 sound_unload_mididev(devc->my_dev);
387 if (!devc->share_irq)
388 free_irq(devc->irq, devc);
392 release_region(hw_config->io_base, 4);
396 void unload_uart401(struct address_info *hw_config)
399 int n=hw_config->slots[4];
402 if(n==-1 || midi_devs[n]==NULL)
405 /* Not allocated (erm ??) */
407 devc = midi_devs[hw_config->slots[4]]->devc;
412 release_region(hw_config->io_base, 4);
414 if (!devc->share_irq)
415 free_irq(devc->irq, devc);
418 kfree(midi_devs[devc->my_dev]->converter);
419 kfree(midi_devs[devc->my_dev]);
423 /* This kills midi_devs[x] */
424 sound_unload_mididev(hw_config->slots[4]);
427 EXPORT_SYMBOL(probe_uart401);
428 EXPORT_SYMBOL(unload_uart401);
429 EXPORT_SYMBOL(uart401intr);
431 static struct address_info cfg_mpu;
436 module_param(io, int, 0444);
437 module_param(irq, int, 0444);
440 static int __init init_uart401(void)
443 cfg_mpu.io_base = io;
445 /* Can be loaded either for module use or to provide functions
447 if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1) {
448 printk(KERN_INFO "MPU-401 UART driver Copyright (C) Hannu Savolainen 1993-1997");
449 if (!probe_uart401(&cfg_mpu, THIS_MODULE))
456 static void __exit cleanup_uart401(void)
458 if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1)
459 unload_uart401(&cfg_mpu);
462 module_init(init_uart401);
463 module_exit(cleanup_uart401);
466 static int __init setup_uart401(char *str)
471 str = get_options(str, ARRAY_SIZE(ints), ints);
479 __setup("uart401=", setup_uart401);
481 MODULE_LICENSE("GPL");