1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * serial.c
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>,
5 * Isaku Yamahata <yamahata@private.email.ne.jp>,
6 * George Hansper <ghansper@apana.org.au>,
7 * Hannu Savolainen
8 *
9 * This code is based on the code from ALSA 0.5.9, but heavily rewritten.
10 *
11 * Sat Mar 31 17:27:57 PST 2001 tim.mann@compaq.com
12 * Added support for the Midiator MS-124T and for the MS-124W in
13 * Single Addressed (S/A) or Multiple Burst (M/B) mode, with
14 * power derived either parasitically from the serial port or
15 * from a separate power supply.
16 *
17 * More documentation can be found in serial-u16550.txt.
18 */
19
20 #include <linux/init.h>
21 #include <linux/interrupt.h>
22 #include <linux/err.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/ioport.h>
26 #include <linux/module.h>
27 #include <linux/io.h>
28 #include <sound/core.h>
29 #include <sound/rawmidi.h>
30 #include <sound/initval.h>
31
32 #include <linux/serial_reg.h>
33 #include <linux/jiffies.h>
34
35 MODULE_DESCRIPTION("MIDI serial u16550");
36 MODULE_LICENSE("GPL");
37 MODULE_SUPPORTED_DEVICE("{{ALSA, MIDI serial u16550}}");
38
39 #define SNDRV_SERIAL_SOUNDCANVAS 0 /* Roland Soundcanvas; F5 NN selects part */
40 #define SNDRV_SERIAL_MS124T 1 /* Midiator MS-124T */
41 #define SNDRV_SERIAL_MS124W_SA 2 /* Midiator MS-124W in S/A mode */
42 #define SNDRV_SERIAL_MS124W_MB 3 /* Midiator MS-124W in M/B mode */
43 #define SNDRV_SERIAL_GENERIC 4 /* Generic Interface */
44 #define SNDRV_SERIAL_MAX_ADAPTOR SNDRV_SERIAL_GENERIC
45 static const char * const adaptor_names[] = {
46 "Soundcanvas",
47 "MS-124T",
48 "MS-124W S/A",
49 "MS-124W M/B",
50 "Generic"
51 };
52
53 #define SNDRV_SERIAL_NORMALBUFF 0 /* Normal blocking buffer operation */
54 #define SNDRV_SERIAL_DROPBUFF 1 /* Non-blocking discard operation */
55
56 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; /* Index 0-MAX */
57 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* ID for this card */
58 static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE; /* Enable this card */
59 static long port[SNDRV_CARDS] = SNDRV_DEFAULT_PORT; /* 0x3f8,0x2f8,0x3e8,0x2e8 */
60 static int irq[SNDRV_CARDS] = SNDRV_DEFAULT_IRQ; /* 3,4,5,7,9,10,11,14,15 */
61 static int speed[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 38400}; /* 9600,19200,38400,57600,115200 */
62 static int base[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 115200}; /* baud base */
63 static int outs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1}; /* 1 to 16 */
64 static int ins[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1}; /* 1 to 16 */
65 static int adaptor[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = SNDRV_SERIAL_SOUNDCANVAS};
66 static bool droponfull[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS -1)] = SNDRV_SERIAL_NORMALBUFF };
67
68 module_param_array(index, int, NULL, 0444);
69 MODULE_PARM_DESC(index, "Index value for Serial MIDI.");
70 module_param_array(id, charp, NULL, 0444);
71 MODULE_PARM_DESC(id, "ID string for Serial MIDI.");
72 module_param_array(enable, bool, NULL, 0444);
73 MODULE_PARM_DESC(enable, "Enable UART16550A chip.");
74 module_param_hw_array(port, long, ioport, NULL, 0444);
75 MODULE_PARM_DESC(port, "Port # for UART16550A chip.");
76 module_param_hw_array(irq, int, irq, NULL, 0444);
77 MODULE_PARM_DESC(irq, "IRQ # for UART16550A chip.");
78 module_param_array(speed, int, NULL, 0444);
79 MODULE_PARM_DESC(speed, "Speed in bauds.");
80 module_param_array(base, int, NULL, 0444);
81 MODULE_PARM_DESC(base, "Base for divisor in bauds.");
82 module_param_array(outs, int, NULL, 0444);
83 MODULE_PARM_DESC(outs, "Number of MIDI outputs.");
84 module_param_array(ins, int, NULL, 0444);
85 MODULE_PARM_DESC(ins, "Number of MIDI inputs.");
86 module_param_array(droponfull, bool, NULL, 0444);
87 MODULE_PARM_DESC(droponfull, "Flag to enable drop-on-full buffer mode");
88
89 module_param_array(adaptor, int, NULL, 0444);
90 MODULE_PARM_DESC(adaptor, "Type of adaptor.");
91
92 /*#define SNDRV_SERIAL_MS124W_MB_NOCOMBO 1*/ /* Address outs as 0-3 instead of bitmap */
93
94 #define SNDRV_SERIAL_MAX_OUTS 16 /* max 64, min 16 */
95 #define SNDRV_SERIAL_MAX_INS 16 /* max 64, min 16 */
96
97 #define TX_BUFF_SIZE (1<<15) /* Must be 2^n */
98 #define TX_BUFF_MASK (TX_BUFF_SIZE - 1)
99
100 #define SERIAL_MODE_NOT_OPENED (0)
101 #define SERIAL_MODE_INPUT_OPEN (1 << 0)
102 #define SERIAL_MODE_OUTPUT_OPEN (1 << 1)
103 #define SERIAL_MODE_INPUT_TRIGGERED (1 << 2)
104 #define SERIAL_MODE_OUTPUT_TRIGGERED (1 << 3)
105
106 struct snd_uart16550 {
107 struct snd_card *card;
108 struct snd_rawmidi *rmidi;
109 struct snd_rawmidi_substream *midi_output[SNDRV_SERIAL_MAX_OUTS];
110 struct snd_rawmidi_substream *midi_input[SNDRV_SERIAL_MAX_INS];
111
112 int filemode; /* open status of file */
113
114 spinlock_t open_lock;
115
116 int irq;
117
118 unsigned long base;
119 struct resource *res_base;
120
121 unsigned int speed;
122 unsigned int speed_base;
123 unsigned char divisor;
124
125 unsigned char old_divisor_lsb;
126 unsigned char old_divisor_msb;
127 unsigned char old_line_ctrl_reg;
128
129 /* parameter for using of write loop */
130 short int fifo_limit; /* used in uart16550 */
131 short int fifo_count; /* used in uart16550 */
132
133 /* type of adaptor */
134 int adaptor;
135
136 /* inputs */
137 int prev_in;
138 unsigned char rstatus;
139
140 /* outputs */
141 int prev_out;
142 unsigned char prev_status[SNDRV_SERIAL_MAX_OUTS];
143
144 /* write buffer and its writing/reading position */
145 unsigned char tx_buff[TX_BUFF_SIZE];
146 int buff_in_count;
147 int buff_in;
148 int buff_out;
149 int drop_on_full;
150
151 /* wait timer */
152 unsigned int timer_running:1;
153 struct timer_list buffer_timer;
154
155 };
156
157 static struct platform_device *devices[SNDRV_CARDS];
158
snd_uart16550_add_timer(struct snd_uart16550 * uart)159 static inline void snd_uart16550_add_timer(struct snd_uart16550 *uart)
160 {
161 if (!uart->timer_running) {
162 /* timer 38600bps * 10bit * 16byte */
163 mod_timer(&uart->buffer_timer, jiffies + (HZ + 255) / 256);
164 uart->timer_running = 1;
165 }
166 }
167
snd_uart16550_del_timer(struct snd_uart16550 * uart)168 static inline void snd_uart16550_del_timer(struct snd_uart16550 *uart)
169 {
170 if (uart->timer_running) {
171 del_timer(&uart->buffer_timer);
172 uart->timer_running = 0;
173 }
174 }
175
176 /* This macro is only used in snd_uart16550_io_loop */
snd_uart16550_buffer_output(struct snd_uart16550 * uart)177 static inline void snd_uart16550_buffer_output(struct snd_uart16550 *uart)
178 {
179 unsigned short buff_out = uart->buff_out;
180 if (uart->buff_in_count > 0) {
181 outb(uart->tx_buff[buff_out], uart->base + UART_TX);
182 uart->fifo_count++;
183 buff_out++;
184 buff_out &= TX_BUFF_MASK;
185 uart->buff_out = buff_out;
186 uart->buff_in_count--;
187 }
188 }
189
190 /* This loop should be called with interrupts disabled
191 * We don't want to interrupt this,
192 * as we're already handling an interrupt
193 */
snd_uart16550_io_loop(struct snd_uart16550 * uart)194 static void snd_uart16550_io_loop(struct snd_uart16550 * uart)
195 {
196 unsigned char c, status;
197 int substream;
198
199 /* recall previous stream */
200 substream = uart->prev_in;
201
202 /* Read Loop */
203 while ((status = inb(uart->base + UART_LSR)) & UART_LSR_DR) {
204 /* while receive data ready */
205 c = inb(uart->base + UART_RX);
206
207 /* keep track of last status byte */
208 if (c & 0x80)
209 uart->rstatus = c;
210
211 /* handle stream switch */
212 if (uart->adaptor == SNDRV_SERIAL_GENERIC) {
213 if (uart->rstatus == 0xf5) {
214 if (c <= SNDRV_SERIAL_MAX_INS && c > 0)
215 substream = c - 1;
216 if (c != 0xf5)
217 /* prevent future bytes from being
218 interpreted as streams */
219 uart->rstatus = 0;
220 } else if ((uart->filemode & SERIAL_MODE_INPUT_OPEN)
221 && uart->midi_input[substream])
222 snd_rawmidi_receive(uart->midi_input[substream],
223 &c, 1);
224 } else if ((uart->filemode & SERIAL_MODE_INPUT_OPEN) &&
225 uart->midi_input[substream])
226 snd_rawmidi_receive(uart->midi_input[substream], &c, 1);
227
228 if (status & UART_LSR_OE)
229 snd_printk(KERN_WARNING
230 "%s: Overrun on device at 0x%lx\n",
231 uart->rmidi->name, uart->base);
232 }
233
234 /* remember the last stream */
235 uart->prev_in = substream;
236
237 /* no need of check SERIAL_MODE_OUTPUT_OPEN because if not,
238 buffer is never filled. */
239 /* Check write status */
240 if (status & UART_LSR_THRE)
241 uart->fifo_count = 0;
242 if (uart->adaptor == SNDRV_SERIAL_MS124W_SA
243 || uart->adaptor == SNDRV_SERIAL_GENERIC) {
244 /* Can't use FIFO, must send only when CTS is true */
245 status = inb(uart->base + UART_MSR);
246 while (uart->fifo_count == 0 && (status & UART_MSR_CTS) &&
247 uart->buff_in_count > 0) {
248 snd_uart16550_buffer_output(uart);
249 status = inb(uart->base + UART_MSR);
250 }
251 } else {
252 /* Write loop */
253 while (uart->fifo_count < uart->fifo_limit /* Can we write ? */
254 && uart->buff_in_count > 0) /* Do we want to? */
255 snd_uart16550_buffer_output(uart);
256 }
257 if (uart->irq < 0 && uart->buff_in_count > 0)
258 snd_uart16550_add_timer(uart);
259 }
260
261 /* NOTES ON SERVICING INTERUPTS
262 * ---------------------------
263 * After receiving a interrupt, it is important to indicate to the UART that
264 * this has been done.
265 * For a Rx interrupt, this is done by reading the received byte.
266 * For a Tx interrupt this is done by either:
267 * a) Writing a byte
268 * b) Reading the IIR
269 * It is particularly important to read the IIR if a Tx interrupt is received
270 * when there is no data in tx_buff[], as in this case there no other
271 * indication that the interrupt has been serviced, and it remains outstanding
272 * indefinitely. This has the curious side effect that and no further interrupts
273 * will be generated from this device AT ALL!!.
274 * It is also desirable to clear outstanding interrupts when the device is
275 * opened/closed.
276 *
277 *
278 * Note that some devices need OUT2 to be set before they will generate
279 * interrupts at all. (Possibly tied to an internal pull-up on CTS?)
280 */
snd_uart16550_interrupt(int irq,void * dev_id)281 static irqreturn_t snd_uart16550_interrupt(int irq, void *dev_id)
282 {
283 struct snd_uart16550 *uart;
284
285 uart = dev_id;
286 spin_lock(&uart->open_lock);
287 if (uart->filemode == SERIAL_MODE_NOT_OPENED) {
288 spin_unlock(&uart->open_lock);
289 return IRQ_NONE;
290 }
291 /* indicate to the UART that the interrupt has been serviced */
292 inb(uart->base + UART_IIR);
293 snd_uart16550_io_loop(uart);
294 spin_unlock(&uart->open_lock);
295 return IRQ_HANDLED;
296 }
297
298 /* When the polling mode, this function calls snd_uart16550_io_loop. */
snd_uart16550_buffer_timer(struct timer_list * t)299 static void snd_uart16550_buffer_timer(struct timer_list *t)
300 {
301 unsigned long flags;
302 struct snd_uart16550 *uart;
303
304 uart = from_timer(uart, t, buffer_timer);
305 spin_lock_irqsave(&uart->open_lock, flags);
306 snd_uart16550_del_timer(uart);
307 snd_uart16550_io_loop(uart);
308 spin_unlock_irqrestore(&uart->open_lock, flags);
309 }
310
311 /*
312 * this method probes, if an uart sits on given port
313 * return 0 if found
314 * return negative error if not found
315 */
snd_uart16550_detect(struct snd_uart16550 * uart)316 static int snd_uart16550_detect(struct snd_uart16550 *uart)
317 {
318 unsigned long io_base = uart->base;
319 int ok;
320 unsigned char c;
321
322 /* Do some vague tests for the presence of the uart */
323 if (io_base == 0 || io_base == SNDRV_AUTO_PORT) {
324 return -ENODEV; /* Not configured */
325 }
326
327 uart->res_base = request_region(io_base, 8, "Serial MIDI");
328 if (uart->res_base == NULL) {
329 snd_printk(KERN_ERR "u16550: can't grab port 0x%lx\n", io_base);
330 return -EBUSY;
331 }
332
333 /* uart detected unless one of the following tests should fail */
334 ok = 1;
335 /* 8 data-bits, 1 stop-bit, parity off, DLAB = 0 */
336 outb(UART_LCR_WLEN8, io_base + UART_LCR); /* Line Control Register */
337 c = inb(io_base + UART_IER);
338 /* The top four bits of the IER should always == 0 */
339 if ((c & 0xf0) != 0)
340 ok = 0; /* failed */
341
342 outb(0xaa, io_base + UART_SCR);
343 /* Write arbitrary data into the scratch reg */
344 c = inb(io_base + UART_SCR);
345 /* If it comes back, it's OK */
346 if (c != 0xaa)
347 ok = 0; /* failed */
348
349 outb(0x55, io_base + UART_SCR);
350 /* Write arbitrary data into the scratch reg */
351 c = inb(io_base + UART_SCR);
352 /* If it comes back, it's OK */
353 if (c != 0x55)
354 ok = 0; /* failed */
355
356 return ok;
357 }
358
snd_uart16550_do_open(struct snd_uart16550 * uart)359 static void snd_uart16550_do_open(struct snd_uart16550 * uart)
360 {
361 char byte;
362
363 /* Initialize basic variables */
364 uart->buff_in_count = 0;
365 uart->buff_in = 0;
366 uart->buff_out = 0;
367 uart->fifo_limit = 1;
368 uart->fifo_count = 0;
369 uart->timer_running = 0;
370
371 outb(UART_FCR_ENABLE_FIFO /* Enable FIFO's (if available) */
372 | UART_FCR_CLEAR_RCVR /* Clear receiver FIFO */
373 | UART_FCR_CLEAR_XMIT /* Clear transmitter FIFO */
374 | UART_FCR_TRIGGER_4 /* Set FIFO trigger at 4-bytes */
375 /* NOTE: interrupt generated after T=(time)4-bytes
376 * if less than UART_FCR_TRIGGER bytes received
377 */
378 ,uart->base + UART_FCR); /* FIFO Control Register */
379
380 if ((inb(uart->base + UART_IIR) & 0xf0) == 0xc0)
381 uart->fifo_limit = 16;
382 if (uart->divisor != 0) {
383 uart->old_line_ctrl_reg = inb(uart->base + UART_LCR);
384 outb(UART_LCR_DLAB /* Divisor latch access bit */
385 ,uart->base + UART_LCR); /* Line Control Register */
386 uart->old_divisor_lsb = inb(uart->base + UART_DLL);
387 uart->old_divisor_msb = inb(uart->base + UART_DLM);
388
389 outb(uart->divisor
390 ,uart->base + UART_DLL); /* Divisor Latch Low */
391 outb(0
392 ,uart->base + UART_DLM); /* Divisor Latch High */
393 /* DLAB is reset to 0 in next outb() */
394 }
395 /* Set serial parameters (parity off, etc) */
396 outb(UART_LCR_WLEN8 /* 8 data-bits */
397 | 0 /* 1 stop-bit */
398 | 0 /* parity off */
399 | 0 /* DLAB = 0 */
400 ,uart->base + UART_LCR); /* Line Control Register */
401
402 switch (uart->adaptor) {
403 default:
404 outb(UART_MCR_RTS /* Set Request-To-Send line active */
405 | UART_MCR_DTR /* Set Data-Terminal-Ready line active */
406 | UART_MCR_OUT2 /* Set OUT2 - not always required, but when
407 * it is, it is ESSENTIAL for enabling interrupts
408 */
409 ,uart->base + UART_MCR); /* Modem Control Register */
410 break;
411 case SNDRV_SERIAL_MS124W_SA:
412 case SNDRV_SERIAL_MS124W_MB:
413 /* MS-124W can draw power from RTS and DTR if they
414 are in opposite states. */
415 outb(UART_MCR_RTS | (0&UART_MCR_DTR) | UART_MCR_OUT2,
416 uart->base + UART_MCR);
417 break;
418 case SNDRV_SERIAL_MS124T:
419 /* MS-124T can draw power from RTS and/or DTR (preferably
420 both) if they are both asserted. */
421 outb(UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2,
422 uart->base + UART_MCR);
423 break;
424 }
425
426 if (uart->irq < 0) {
427 byte = (0 & UART_IER_RDI) /* Disable Receiver data interrupt */
428 |(0 & UART_IER_THRI) /* Disable Transmitter holding register empty interrupt */
429 ;
430 } else if (uart->adaptor == SNDRV_SERIAL_MS124W_SA) {
431 byte = UART_IER_RDI /* Enable Receiver data interrupt */
432 | UART_IER_MSI /* Enable Modem status interrupt */
433 ;
434 } else if (uart->adaptor == SNDRV_SERIAL_GENERIC) {
435 byte = UART_IER_RDI /* Enable Receiver data interrupt */
436 | UART_IER_MSI /* Enable Modem status interrupt */
437 | UART_IER_THRI /* Enable Transmitter holding register empty interrupt */
438 ;
439 } else {
440 byte = UART_IER_RDI /* Enable Receiver data interrupt */
441 | UART_IER_THRI /* Enable Transmitter holding register empty interrupt */
442 ;
443 }
444 outb(byte, uart->base + UART_IER); /* Interrupt enable Register */
445
446 inb(uart->base + UART_LSR); /* Clear any pre-existing overrun indication */
447 inb(uart->base + UART_IIR); /* Clear any pre-existing transmit interrupt */
448 inb(uart->base + UART_RX); /* Clear any pre-existing receive interrupt */
449 }
450
snd_uart16550_do_close(struct snd_uart16550 * uart)451 static void snd_uart16550_do_close(struct snd_uart16550 * uart)
452 {
453 if (uart->irq < 0)
454 snd_uart16550_del_timer(uart);
455
456 /* NOTE: may need to disable interrupts before de-registering out handler.
457 * For now, the consequences are harmless.
458 */
459
460 outb((0 & UART_IER_RDI) /* Disable Receiver data interrupt */
461 |(0 & UART_IER_THRI) /* Disable Transmitter holding register empty interrupt */
462 ,uart->base + UART_IER); /* Interrupt enable Register */
463
464 switch (uart->adaptor) {
465 default:
466 outb((0 & UART_MCR_RTS) /* Deactivate Request-To-Send line */
467 |(0 & UART_MCR_DTR) /* Deactivate Data-Terminal-Ready line */
468 |(0 & UART_MCR_OUT2) /* Deactivate OUT2 */
469 ,uart->base + UART_MCR); /* Modem Control Register */
470 break;
471 case SNDRV_SERIAL_MS124W_SA:
472 case SNDRV_SERIAL_MS124W_MB:
473 /* MS-124W can draw power from RTS and DTR if they
474 are in opposite states; leave it powered. */
475 outb(UART_MCR_RTS | (0&UART_MCR_DTR) | (0&UART_MCR_OUT2),
476 uart->base + UART_MCR);
477 break;
478 case SNDRV_SERIAL_MS124T:
479 /* MS-124T can draw power from RTS and/or DTR (preferably
480 both) if they are both asserted; leave it powered. */
481 outb(UART_MCR_RTS | UART_MCR_DTR | (0&UART_MCR_OUT2),
482 uart->base + UART_MCR);
483 break;
484 }
485
486 inb(uart->base + UART_IIR); /* Clear any outstanding interrupts */
487
488 /* Restore old divisor */
489 if (uart->divisor != 0) {
490 outb(UART_LCR_DLAB /* Divisor latch access bit */
491 ,uart->base + UART_LCR); /* Line Control Register */
492 outb(uart->old_divisor_lsb
493 ,uart->base + UART_DLL); /* Divisor Latch Low */
494 outb(uart->old_divisor_msb
495 ,uart->base + UART_DLM); /* Divisor Latch High */
496 /* Restore old LCR (data bits, stop bits, parity, DLAB) */
497 outb(uart->old_line_ctrl_reg
498 ,uart->base + UART_LCR); /* Line Control Register */
499 }
500 }
501
snd_uart16550_input_open(struct snd_rawmidi_substream * substream)502 static int snd_uart16550_input_open(struct snd_rawmidi_substream *substream)
503 {
504 unsigned long flags;
505 struct snd_uart16550 *uart = substream->rmidi->private_data;
506
507 spin_lock_irqsave(&uart->open_lock, flags);
508 if (uart->filemode == SERIAL_MODE_NOT_OPENED)
509 snd_uart16550_do_open(uart);
510 uart->filemode |= SERIAL_MODE_INPUT_OPEN;
511 uart->midi_input[substream->number] = substream;
512 spin_unlock_irqrestore(&uart->open_lock, flags);
513 return 0;
514 }
515
snd_uart16550_input_close(struct snd_rawmidi_substream * substream)516 static int snd_uart16550_input_close(struct snd_rawmidi_substream *substream)
517 {
518 unsigned long flags;
519 struct snd_uart16550 *uart = substream->rmidi->private_data;
520
521 spin_lock_irqsave(&uart->open_lock, flags);
522 uart->filemode &= ~SERIAL_MODE_INPUT_OPEN;
523 uart->midi_input[substream->number] = NULL;
524 if (uart->filemode == SERIAL_MODE_NOT_OPENED)
525 snd_uart16550_do_close(uart);
526 spin_unlock_irqrestore(&uart->open_lock, flags);
527 return 0;
528 }
529
snd_uart16550_input_trigger(struct snd_rawmidi_substream * substream,int up)530 static void snd_uart16550_input_trigger(struct snd_rawmidi_substream *substream,
531 int up)
532 {
533 unsigned long flags;
534 struct snd_uart16550 *uart = substream->rmidi->private_data;
535
536 spin_lock_irqsave(&uart->open_lock, flags);
537 if (up)
538 uart->filemode |= SERIAL_MODE_INPUT_TRIGGERED;
539 else
540 uart->filemode &= ~SERIAL_MODE_INPUT_TRIGGERED;
541 spin_unlock_irqrestore(&uart->open_lock, flags);
542 }
543
snd_uart16550_output_open(struct snd_rawmidi_substream * substream)544 static int snd_uart16550_output_open(struct snd_rawmidi_substream *substream)
545 {
546 unsigned long flags;
547 struct snd_uart16550 *uart = substream->rmidi->private_data;
548
549 spin_lock_irqsave(&uart->open_lock, flags);
550 if (uart->filemode == SERIAL_MODE_NOT_OPENED)
551 snd_uart16550_do_open(uart);
552 uart->filemode |= SERIAL_MODE_OUTPUT_OPEN;
553 uart->midi_output[substream->number] = substream;
554 spin_unlock_irqrestore(&uart->open_lock, flags);
555 return 0;
556 };
557
snd_uart16550_output_close(struct snd_rawmidi_substream * substream)558 static int snd_uart16550_output_close(struct snd_rawmidi_substream *substream)
559 {
560 unsigned long flags;
561 struct snd_uart16550 *uart = substream->rmidi->private_data;
562
563 spin_lock_irqsave(&uart->open_lock, flags);
564 uart->filemode &= ~SERIAL_MODE_OUTPUT_OPEN;
565 uart->midi_output[substream->number] = NULL;
566 if (uart->filemode == SERIAL_MODE_NOT_OPENED)
567 snd_uart16550_do_close(uart);
568 spin_unlock_irqrestore(&uart->open_lock, flags);
569 return 0;
570 };
571
snd_uart16550_buffer_can_write(struct snd_uart16550 * uart,int Num)572 static inline int snd_uart16550_buffer_can_write(struct snd_uart16550 *uart,
573 int Num)
574 {
575 if (uart->buff_in_count + Num < TX_BUFF_SIZE)
576 return 1;
577 else
578 return 0;
579 }
580
snd_uart16550_write_buffer(struct snd_uart16550 * uart,unsigned char byte)581 static inline int snd_uart16550_write_buffer(struct snd_uart16550 *uart,
582 unsigned char byte)
583 {
584 unsigned short buff_in = uart->buff_in;
585 if (uart->buff_in_count < TX_BUFF_SIZE) {
586 uart->tx_buff[buff_in] = byte;
587 buff_in++;
588 buff_in &= TX_BUFF_MASK;
589 uart->buff_in = buff_in;
590 uart->buff_in_count++;
591 if (uart->irq < 0) /* polling mode */
592 snd_uart16550_add_timer(uart);
593 return 1;
594 } else
595 return 0;
596 }
597
snd_uart16550_output_byte(struct snd_uart16550 * uart,struct snd_rawmidi_substream * substream,unsigned char midi_byte)598 static int snd_uart16550_output_byte(struct snd_uart16550 *uart,
599 struct snd_rawmidi_substream *substream,
600 unsigned char midi_byte)
601 {
602 if (uart->buff_in_count == 0 /* Buffer empty? */
603 && ((uart->adaptor != SNDRV_SERIAL_MS124W_SA &&
604 uart->adaptor != SNDRV_SERIAL_GENERIC) ||
605 (uart->fifo_count == 0 /* FIFO empty? */
606 && (inb(uart->base + UART_MSR) & UART_MSR_CTS)))) { /* CTS? */
607
608 /* Tx Buffer Empty - try to write immediately */
609 if ((inb(uart->base + UART_LSR) & UART_LSR_THRE) != 0) {
610 /* Transmitter holding register (and Tx FIFO) empty */
611 uart->fifo_count = 1;
612 outb(midi_byte, uart->base + UART_TX);
613 } else {
614 if (uart->fifo_count < uart->fifo_limit) {
615 uart->fifo_count++;
616 outb(midi_byte, uart->base + UART_TX);
617 } else {
618 /* Cannot write (buffer empty) -
619 * put char in buffer */
620 snd_uart16550_write_buffer(uart, midi_byte);
621 }
622 }
623 } else {
624 if (!snd_uart16550_write_buffer(uart, midi_byte)) {
625 snd_printk(KERN_WARNING
626 "%s: Buffer overrun on device at 0x%lx\n",
627 uart->rmidi->name, uart->base);
628 return 0;
629 }
630 }
631
632 return 1;
633 }
634
snd_uart16550_output_write(struct snd_rawmidi_substream * substream)635 static void snd_uart16550_output_write(struct snd_rawmidi_substream *substream)
636 {
637 unsigned long flags;
638 unsigned char midi_byte, addr_byte;
639 struct snd_uart16550 *uart = substream->rmidi->private_data;
640 char first;
641 static unsigned long lasttime = 0;
642
643 /* Interrupts are disabled during the updating of the tx_buff,
644 * since it is 'bad' to have two processes updating the same
645 * variables (ie buff_in & buff_out)
646 */
647
648 spin_lock_irqsave(&uart->open_lock, flags);
649
650 if (uart->irq < 0) /* polling */
651 snd_uart16550_io_loop(uart);
652
653 if (uart->adaptor == SNDRV_SERIAL_MS124W_MB) {
654 while (1) {
655 /* buffer full? */
656 /* in this mode we need two bytes of space */
657 if (uart->buff_in_count > TX_BUFF_SIZE - 2)
658 break;
659 if (snd_rawmidi_transmit(substream, &midi_byte, 1) != 1)
660 break;
661 #ifdef SNDRV_SERIAL_MS124W_MB_NOCOMBO
662 /* select exactly one of the four ports */
663 addr_byte = (1 << (substream->number + 4)) | 0x08;
664 #else
665 /* select any combination of the four ports */
666 addr_byte = (substream->number << 4) | 0x08;
667 /* ...except none */
668 if (addr_byte == 0x08)
669 addr_byte = 0xf8;
670 #endif
671 snd_uart16550_output_byte(uart, substream, addr_byte);
672 /* send midi byte */
673 snd_uart16550_output_byte(uart, substream, midi_byte);
674 }
675 } else {
676 first = 0;
677 while (snd_rawmidi_transmit_peek(substream, &midi_byte, 1) == 1) {
678 /* Also send F5 after 3 seconds with no data
679 * to handle device disconnect */
680 if (first == 0 &&
681 (uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS ||
682 uart->adaptor == SNDRV_SERIAL_GENERIC) &&
683 (uart->prev_out != substream->number ||
684 time_after(jiffies, lasttime + 3*HZ))) {
685
686 if (snd_uart16550_buffer_can_write(uart, 3)) {
687 /* Roland Soundcanvas part selection */
688 /* If this substream of the data is
689 * different previous substream
690 * in this uart, send the change part
691 * event
692 */
693 uart->prev_out = substream->number;
694 /* change part */
695 snd_uart16550_output_byte(uart, substream,
696 0xf5);
697 /* data */
698 snd_uart16550_output_byte(uart, substream,
699 uart->prev_out + 1);
700 /* If midi_byte is a data byte,
701 * send the previous status byte */
702 if (midi_byte < 0x80 &&
703 uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS)
704 snd_uart16550_output_byte(uart, substream, uart->prev_status[uart->prev_out]);
705 } else if (!uart->drop_on_full)
706 break;
707
708 }
709
710 /* send midi byte */
711 if (!snd_uart16550_output_byte(uart, substream, midi_byte) &&
712 !uart->drop_on_full )
713 break;
714
715 if (midi_byte >= 0x80 && midi_byte < 0xf0)
716 uart->prev_status[uart->prev_out] = midi_byte;
717 first = 1;
718
719 snd_rawmidi_transmit_ack( substream, 1 );
720 }
721 lasttime = jiffies;
722 }
723 spin_unlock_irqrestore(&uart->open_lock, flags);
724 }
725
snd_uart16550_output_trigger(struct snd_rawmidi_substream * substream,int up)726 static void snd_uart16550_output_trigger(struct snd_rawmidi_substream *substream,
727 int up)
728 {
729 unsigned long flags;
730 struct snd_uart16550 *uart = substream->rmidi->private_data;
731
732 spin_lock_irqsave(&uart->open_lock, flags);
733 if (up)
734 uart->filemode |= SERIAL_MODE_OUTPUT_TRIGGERED;
735 else
736 uart->filemode &= ~SERIAL_MODE_OUTPUT_TRIGGERED;
737 spin_unlock_irqrestore(&uart->open_lock, flags);
738 if (up)
739 snd_uart16550_output_write(substream);
740 }
741
742 static const struct snd_rawmidi_ops snd_uart16550_output =
743 {
744 .open = snd_uart16550_output_open,
745 .close = snd_uart16550_output_close,
746 .trigger = snd_uart16550_output_trigger,
747 };
748
749 static const struct snd_rawmidi_ops snd_uart16550_input =
750 {
751 .open = snd_uart16550_input_open,
752 .close = snd_uart16550_input_close,
753 .trigger = snd_uart16550_input_trigger,
754 };
755
snd_uart16550_free(struct snd_uart16550 * uart)756 static int snd_uart16550_free(struct snd_uart16550 *uart)
757 {
758 if (uart->irq >= 0)
759 free_irq(uart->irq, uart);
760 release_and_free_resource(uart->res_base);
761 kfree(uart);
762 return 0;
763 };
764
snd_uart16550_dev_free(struct snd_device * device)765 static int snd_uart16550_dev_free(struct snd_device *device)
766 {
767 struct snd_uart16550 *uart = device->device_data;
768 return snd_uart16550_free(uart);
769 }
770
snd_uart16550_create(struct snd_card * card,unsigned long iobase,int irq,unsigned int speed,unsigned int base,int adaptor,int droponfull,struct snd_uart16550 ** ruart)771 static int snd_uart16550_create(struct snd_card *card,
772 unsigned long iobase,
773 int irq,
774 unsigned int speed,
775 unsigned int base,
776 int adaptor,
777 int droponfull,
778 struct snd_uart16550 **ruart)
779 {
780 static const struct snd_device_ops ops = {
781 .dev_free = snd_uart16550_dev_free,
782 };
783 struct snd_uart16550 *uart;
784 int err;
785
786
787 if ((uart = kzalloc(sizeof(*uart), GFP_KERNEL)) == NULL)
788 return -ENOMEM;
789 uart->adaptor = adaptor;
790 uart->card = card;
791 spin_lock_init(&uart->open_lock);
792 uart->irq = -1;
793 uart->base = iobase;
794 uart->drop_on_full = droponfull;
795
796 if ((err = snd_uart16550_detect(uart)) <= 0) {
797 printk(KERN_ERR "no UART detected at 0x%lx\n", iobase);
798 snd_uart16550_free(uart);
799 return -ENODEV;
800 }
801
802 if (irq >= 0 && irq != SNDRV_AUTO_IRQ) {
803 if (request_irq(irq, snd_uart16550_interrupt,
804 0, "Serial MIDI", uart)) {
805 snd_printk(KERN_WARNING
806 "irq %d busy. Using Polling.\n", irq);
807 } else {
808 uart->irq = irq;
809 }
810 }
811 uart->divisor = base / speed;
812 uart->speed = base / (unsigned int)uart->divisor;
813 uart->speed_base = base;
814 uart->prev_out = -1;
815 uart->prev_in = 0;
816 uart->rstatus = 0;
817 memset(uart->prev_status, 0x80, sizeof(unsigned char) * SNDRV_SERIAL_MAX_OUTS);
818 timer_setup(&uart->buffer_timer, snd_uart16550_buffer_timer, 0);
819 uart->timer_running = 0;
820
821 /* Register device */
822 if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, uart, &ops)) < 0) {
823 snd_uart16550_free(uart);
824 return err;
825 }
826
827 switch (uart->adaptor) {
828 case SNDRV_SERIAL_MS124W_SA:
829 case SNDRV_SERIAL_MS124W_MB:
830 /* MS-124W can draw power from RTS and DTR if they
831 are in opposite states. */
832 outb(UART_MCR_RTS | (0&UART_MCR_DTR), uart->base + UART_MCR);
833 break;
834 case SNDRV_SERIAL_MS124T:
835 /* MS-124T can draw power from RTS and/or DTR (preferably
836 both) if they are asserted. */
837 outb(UART_MCR_RTS | UART_MCR_DTR, uart->base + UART_MCR);
838 break;
839 default:
840 break;
841 }
842
843 if (ruart)
844 *ruart = uart;
845
846 return 0;
847 }
848
snd_uart16550_substreams(struct snd_rawmidi_str * stream)849 static void snd_uart16550_substreams(struct snd_rawmidi_str *stream)
850 {
851 struct snd_rawmidi_substream *substream;
852
853 list_for_each_entry(substream, &stream->substreams, list) {
854 sprintf(substream->name, "Serial MIDI %d", substream->number + 1);
855 }
856 }
857
snd_uart16550_rmidi(struct snd_uart16550 * uart,int device,int outs,int ins,struct snd_rawmidi ** rmidi)858 static int snd_uart16550_rmidi(struct snd_uart16550 *uart, int device,
859 int outs, int ins,
860 struct snd_rawmidi **rmidi)
861 {
862 struct snd_rawmidi *rrawmidi;
863 int err;
864
865 err = snd_rawmidi_new(uart->card, "UART Serial MIDI", device,
866 outs, ins, &rrawmidi);
867 if (err < 0)
868 return err;
869 snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_INPUT,
870 &snd_uart16550_input);
871 snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
872 &snd_uart16550_output);
873 strcpy(rrawmidi->name, "Serial MIDI");
874 snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
875 snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
876 rrawmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
877 SNDRV_RAWMIDI_INFO_INPUT |
878 SNDRV_RAWMIDI_INFO_DUPLEX;
879 rrawmidi->private_data = uart;
880 if (rmidi)
881 *rmidi = rrawmidi;
882 return 0;
883 }
884
snd_serial_probe(struct platform_device * devptr)885 static int snd_serial_probe(struct platform_device *devptr)
886 {
887 struct snd_card *card;
888 struct snd_uart16550 *uart;
889 int err;
890 int dev = devptr->id;
891
892 switch (adaptor[dev]) {
893 case SNDRV_SERIAL_SOUNDCANVAS:
894 ins[dev] = 1;
895 break;
896 case SNDRV_SERIAL_MS124T:
897 case SNDRV_SERIAL_MS124W_SA:
898 outs[dev] = 1;
899 ins[dev] = 1;
900 break;
901 case SNDRV_SERIAL_MS124W_MB:
902 outs[dev] = 16;
903 ins[dev] = 1;
904 break;
905 case SNDRV_SERIAL_GENERIC:
906 break;
907 default:
908 snd_printk(KERN_ERR
909 "Adaptor type is out of range 0-%d (%d)\n",
910 SNDRV_SERIAL_MAX_ADAPTOR, adaptor[dev]);
911 return -ENODEV;
912 }
913
914 if (outs[dev] < 1 || outs[dev] > SNDRV_SERIAL_MAX_OUTS) {
915 snd_printk(KERN_ERR
916 "Count of outputs is out of range 1-%d (%d)\n",
917 SNDRV_SERIAL_MAX_OUTS, outs[dev]);
918 return -ENODEV;
919 }
920
921 if (ins[dev] < 1 || ins[dev] > SNDRV_SERIAL_MAX_INS) {
922 snd_printk(KERN_ERR
923 "Count of inputs is out of range 1-%d (%d)\n",
924 SNDRV_SERIAL_MAX_INS, ins[dev]);
925 return -ENODEV;
926 }
927
928 err = snd_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
929 0, &card);
930 if (err < 0)
931 return err;
932
933 strcpy(card->driver, "Serial");
934 strcpy(card->shortname, "Serial MIDI (UART16550A)");
935
936 if ((err = snd_uart16550_create(card,
937 port[dev],
938 irq[dev],
939 speed[dev],
940 base[dev],
941 adaptor[dev],
942 droponfull[dev],
943 &uart)) < 0)
944 goto _err;
945
946 err = snd_uart16550_rmidi(uart, 0, outs[dev], ins[dev], &uart->rmidi);
947 if (err < 0)
948 goto _err;
949
950 sprintf(card->longname, "%s [%s] at %#lx, irq %d",
951 card->shortname,
952 adaptor_names[uart->adaptor],
953 uart->base,
954 uart->irq);
955
956 if ((err = snd_card_register(card)) < 0)
957 goto _err;
958
959 platform_set_drvdata(devptr, card);
960 return 0;
961
962 _err:
963 snd_card_free(card);
964 return err;
965 }
966
snd_serial_remove(struct platform_device * devptr)967 static int snd_serial_remove(struct platform_device *devptr)
968 {
969 snd_card_free(platform_get_drvdata(devptr));
970 return 0;
971 }
972
973 #define SND_SERIAL_DRIVER "snd_serial_u16550"
974
975 static struct platform_driver snd_serial_driver = {
976 .probe = snd_serial_probe,
977 .remove = snd_serial_remove,
978 .driver = {
979 .name = SND_SERIAL_DRIVER,
980 },
981 };
982
snd_serial_unregister_all(void)983 static void snd_serial_unregister_all(void)
984 {
985 int i;
986
987 for (i = 0; i < ARRAY_SIZE(devices); ++i)
988 platform_device_unregister(devices[i]);
989 platform_driver_unregister(&snd_serial_driver);
990 }
991
alsa_card_serial_init(void)992 static int __init alsa_card_serial_init(void)
993 {
994 int i, cards, err;
995
996 if ((err = platform_driver_register(&snd_serial_driver)) < 0)
997 return err;
998
999 cards = 0;
1000 for (i = 0; i < SNDRV_CARDS; i++) {
1001 struct platform_device *device;
1002 if (! enable[i])
1003 continue;
1004 device = platform_device_register_simple(SND_SERIAL_DRIVER,
1005 i, NULL, 0);
1006 if (IS_ERR(device))
1007 continue;
1008 if (!platform_get_drvdata(device)) {
1009 platform_device_unregister(device);
1010 continue;
1011 }
1012 devices[i] = device;
1013 cards++;
1014 }
1015 if (! cards) {
1016 #ifdef MODULE
1017 printk(KERN_ERR "serial midi soundcard not found or device busy\n");
1018 #endif
1019 snd_serial_unregister_all();
1020 return -ENODEV;
1021 }
1022 return 0;
1023 }
1024
alsa_card_serial_exit(void)1025 static void __exit alsa_card_serial_exit(void)
1026 {
1027 snd_serial_unregister_all();
1028 }
1029
1030 module_init(alsa_card_serial_init)
1031 module_exit(alsa_card_serial_exit)
1032
