xref: /linux/sound/drivers/portman2x4.c (revision bbcd53c960713507ae764bf81970651b5577b95a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   Driver for Midiman Portman2x4 parallel port midi interface
4  *
5  *   Copyright (c) by Levent Guendogdu <levon@feature-it.com>
6  *
7  * ChangeLog
8  * Jan 24 2007 Matthias Koenig <mkoenig@suse.de>
9  *      - cleanup and rewrite
10  * Sep 30 2004 Tobias Gehrig <tobias@gehrig.tk>
11  *      - source code cleanup
12  * Sep 03 2004 Tobias Gehrig <tobias@gehrig.tk>
13  *      - fixed compilation problem with alsa 1.0.6a (removed MODULE_CLASSES,
14  *        MODULE_PARM_SYNTAX and changed MODULE_DEVICES to
15  *        MODULE_SUPPORTED_DEVICE)
16  * Mar 24 2004 Tobias Gehrig <tobias@gehrig.tk>
17  *      - added 2.6 kernel support
18  * Mar 18 2004 Tobias Gehrig <tobias@gehrig.tk>
19  *      - added parport_unregister_driver to the startup routine if the driver fails to detect a portman
20  *      - added support for all 4 output ports in portman_putmidi
21  * Mar 17 2004 Tobias Gehrig <tobias@gehrig.tk>
22  *      - added checks for opened input device in interrupt handler
23  * Feb 20 2004 Tobias Gehrig <tobias@gehrig.tk>
24  *      - ported from alsa 0.5 to 1.0
25  */
26 
27 #include <linux/init.h>
28 #include <linux/platform_device.h>
29 #include <linux/parport.h>
30 #include <linux/spinlock.h>
31 #include <linux/delay.h>
32 #include <linux/slab.h>
33 #include <linux/module.h>
34 #include <sound/core.h>
35 #include <sound/initval.h>
36 #include <sound/rawmidi.h>
37 #include <sound/control.h>
38 
39 #define CARD_NAME "Portman 2x4"
40 #define DRIVER_NAME "portman"
41 #define PLATFORM_DRIVER "snd_portman2x4"
42 
43 static int index[SNDRV_CARDS]  = SNDRV_DEFAULT_IDX;
44 static char *id[SNDRV_CARDS]   = SNDRV_DEFAULT_STR;
45 static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;
46 
47 static struct platform_device *platform_devices[SNDRV_CARDS];
48 static int device_count;
49 
50 module_param_array(index, int, NULL, 0444);
51 MODULE_PARM_DESC(index, "Index value for " CARD_NAME " soundcard.");
52 module_param_array(id, charp, NULL, 0444);
53 MODULE_PARM_DESC(id, "ID string for " CARD_NAME " soundcard.");
54 module_param_array(enable, bool, NULL, 0444);
55 MODULE_PARM_DESC(enable, "Enable " CARD_NAME " soundcard.");
56 
57 MODULE_AUTHOR("Levent Guendogdu, Tobias Gehrig, Matthias Koenig");
58 MODULE_DESCRIPTION("Midiman Portman2x4");
59 MODULE_LICENSE("GPL");
60 
61 /*********************************************************************
62  * Chip specific
63  *********************************************************************/
64 #define PORTMAN_NUM_INPUT_PORTS 2
65 #define PORTMAN_NUM_OUTPUT_PORTS 4
66 
67 struct portman {
68 	spinlock_t reg_lock;
69 	struct snd_card *card;
70 	struct snd_rawmidi *rmidi;
71 	struct pardevice *pardev;
72 	int open_count;
73 	int mode[PORTMAN_NUM_INPUT_PORTS];
74 	struct snd_rawmidi_substream *midi_input[PORTMAN_NUM_INPUT_PORTS];
75 };
76 
77 static int portman_free(struct portman *pm)
78 {
79 	kfree(pm);
80 	return 0;
81 }
82 
83 static int portman_create(struct snd_card *card,
84 			  struct pardevice *pardev,
85 			  struct portman **rchip)
86 {
87 	struct portman *pm;
88 
89 	*rchip = NULL;
90 
91 	pm = kzalloc(sizeof(struct portman), GFP_KERNEL);
92 	if (pm == NULL)
93 		return -ENOMEM;
94 
95 	/* Init chip specific data */
96 	spin_lock_init(&pm->reg_lock);
97 	pm->card = card;
98 	pm->pardev = pardev;
99 
100 	*rchip = pm;
101 
102 	return 0;
103 }
104 
105 /*********************************************************************
106  * HW related constants
107  *********************************************************************/
108 
109 /* Standard PC parallel port status register equates. */
110 #define	PP_STAT_BSY   	0x80	/* Busy status.  Inverted. */
111 #define	PP_STAT_ACK   	0x40	/* Acknowledge.  Non-Inverted. */
112 #define	PP_STAT_POUT  	0x20	/* Paper Out.    Non-Inverted. */
113 #define	PP_STAT_SEL   	0x10	/* Select.       Non-Inverted. */
114 #define	PP_STAT_ERR   	0x08	/* Error.        Non-Inverted. */
115 
116 /* Standard PC parallel port command register equates. */
117 #define	PP_CMD_IEN  	0x10	/* IRQ Enable.   Non-Inverted. */
118 #define	PP_CMD_SELI 	0x08	/* Select Input. Inverted. */
119 #define	PP_CMD_INIT 	0x04	/* Init Printer. Non-Inverted. */
120 #define	PP_CMD_FEED 	0x02	/* Auto Feed.    Inverted. */
121 #define	PP_CMD_STB      0x01	/* Strobe.       Inverted. */
122 
123 /* Parallel Port Command Register as implemented by PCP2x4. */
124 #define	INT_EN	 	PP_CMD_IEN	/* Interrupt enable. */
125 #define	STROBE	        PP_CMD_STB	/* Command strobe. */
126 
127 /* The parallel port command register field (b1..b3) selects the
128  * various "registers" within the PC/P 2x4.  These are the internal
129  * address of these "registers" that must be written to the parallel
130  * port command register.
131  */
132 #define	RXDATA0		(0 << 1)	/* PCP RxData channel 0. */
133 #define	RXDATA1		(1 << 1)	/* PCP RxData channel 1. */
134 #define	GEN_CTL		(2 << 1)	/* PCP General Control Register. */
135 #define	SYNC_CTL 	(3 << 1)	/* PCP Sync Control Register. */
136 #define	TXDATA0		(4 << 1)	/* PCP TxData channel 0. */
137 #define	TXDATA1		(5 << 1)	/* PCP TxData channel 1. */
138 #define	TXDATA2		(6 << 1)	/* PCP TxData channel 2. */
139 #define	TXDATA3		(7 << 1)	/* PCP TxData channel 3. */
140 
141 /* Parallel Port Status Register as implemented by PCP2x4. */
142 #define	ESTB		PP_STAT_POUT	/* Echoed strobe. */
143 #define	INT_REQ         PP_STAT_ACK	/* Input data int request. */
144 #define	BUSY            PP_STAT_ERR	/* Interface Busy. */
145 
146 /* Parallel Port Status Register BUSY and SELECT lines are multiplexed
147  * between several functions.  Depending on which 2x4 "register" is
148  * currently selected (b1..b3), the BUSY and SELECT lines are
149  * assigned as follows:
150  *
151  *   SELECT LINE:                                                    A3 A2 A1
152  *                                                                   --------
153  */
154 #define	RXAVAIL		PP_STAT_SEL	/* Rx Available, channel 0.   0 0 0 */
155 //  RXAVAIL1    PP_STAT_SEL             /* Rx Available, channel 1.   0 0 1 */
156 #define	SYNC_STAT	PP_STAT_SEL	/* Reserved - Sync Status.    0 1 0 */
157 //                                      /* Reserved.                  0 1 1 */
158 #define	TXEMPTY		PP_STAT_SEL	/* Tx Empty, channel 0.       1 0 0 */
159 //      TXEMPTY1        PP_STAT_SEL     /* Tx Empty, channel 1.       1 0 1 */
160 //  TXEMPTY2    PP_STAT_SEL             /* Tx Empty, channel 2.       1 1 0 */
161 //  TXEMPTY3    PP_STAT_SEL             /* Tx Empty, channel 3.       1 1 1 */
162 
163 /*   BUSY LINE:                                                      A3 A2 A1
164  *                                                                   --------
165  */
166 #define	RXDATA		PP_STAT_BSY	/* Rx Input Data, channel 0.  0 0 0 */
167 //      RXDATA1         PP_STAT_BSY     /* Rx Input Data, channel 1.  0 0 1 */
168 #define	SYNC_DATA       PP_STAT_BSY	/* Reserved - Sync Data.      0 1 0 */
169 					/* Reserved.                  0 1 1 */
170 #define	DATA_ECHO       PP_STAT_BSY	/* Parallel Port Data Echo.   1 0 0 */
171 #define	A0_ECHO         PP_STAT_BSY	/* Address 0 Echo.            1 0 1 */
172 #define	A1_ECHO         PP_STAT_BSY	/* Address 1 Echo.            1 1 0 */
173 #define	A2_ECHO         PP_STAT_BSY	/* Address 2 Echo.            1 1 1 */
174 
175 #define PORTMAN2X4_MODE_INPUT_TRIGGERED	 0x01
176 
177 /*********************************************************************
178  * Hardware specific functions
179  *********************************************************************/
180 static inline void portman_write_command(struct portman *pm, u8 value)
181 {
182 	parport_write_control(pm->pardev->port, value);
183 }
184 
185 static inline u8 portman_read_command(struct portman *pm)
186 {
187 	return parport_read_control(pm->pardev->port);
188 }
189 
190 static inline u8 portman_read_status(struct portman *pm)
191 {
192 	return parport_read_status(pm->pardev->port);
193 }
194 
195 static inline u8 portman_read_data(struct portman *pm)
196 {
197 	return parport_read_data(pm->pardev->port);
198 }
199 
200 static inline void portman_write_data(struct portman *pm, u8 value)
201 {
202 	parport_write_data(pm->pardev->port, value);
203 }
204 
205 static void portman_write_midi(struct portman *pm,
206 			       int port, u8 mididata)
207 {
208 	int command = ((port + 4) << 1);
209 
210 	/* Get entering data byte and port number in BL and BH respectively.
211 	 * Set up Tx Channel address field for use with PP Cmd Register.
212 	 * Store address field in BH register.
213 	 * Inputs:      AH = Output port number (0..3).
214 	 *              AL = Data byte.
215 	 *    command = TXDATA0 | INT_EN;
216 	 * Align port num with address field (b1...b3),
217 	 * set address for TXDatax, Strobe=0
218 	 */
219 	command |= INT_EN;
220 
221 	/* Disable interrupts so that the process is not interrupted, then
222 	 * write the address associated with the current Tx channel to the
223 	 * PP Command Reg.  Do not set the Strobe signal yet.
224 	 */
225 
226 	do {
227 		portman_write_command(pm, command);
228 
229 		/* While the address lines settle, write parallel output data to
230 		 * PP Data Reg.  This has no effect until Strobe signal is asserted.
231 		 */
232 
233 		portman_write_data(pm, mididata);
234 
235 		/* If PCP channel's TxEmpty is set (TxEmpty is read through the PP
236 		 * Status Register), then go write data.  Else go back and wait.
237 		 */
238 	} while ((portman_read_status(pm) & TXEMPTY) != TXEMPTY);
239 
240 	/* TxEmpty is set.  Maintain PC/P destination address and assert
241 	 * Strobe through the PP Command Reg.  This will Strobe data into
242 	 * the PC/P transmitter and set the PC/P BUSY signal.
243 	 */
244 
245 	portman_write_command(pm, command | STROBE);
246 
247 	/* Wait for strobe line to settle and echo back through hardware.
248 	 * Once it has echoed back, assume that the address and data lines
249 	 * have settled!
250 	 */
251 
252 	while ((portman_read_status(pm) & ESTB) == 0)
253 		cpu_relax();
254 
255 	/* Release strobe and immediately re-allow interrupts. */
256 	portman_write_command(pm, command);
257 
258 	while ((portman_read_status(pm) & ESTB) == ESTB)
259 		cpu_relax();
260 
261 	/* PC/P BUSY is now set.  We must wait until BUSY resets itself.
262 	 * We'll reenable ints while we're waiting.
263 	 */
264 
265 	while ((portman_read_status(pm) & BUSY) == BUSY)
266 		cpu_relax();
267 
268 	/* Data sent. */
269 }
270 
271 
272 /*
273  *  Read MIDI byte from port
274  *  Attempt to read input byte from specified hardware input port (0..).
275  *  Return -1 if no data
276  */
277 static int portman_read_midi(struct portman *pm, int port)
278 {
279 	unsigned char midi_data = 0;
280 	unsigned char cmdout;	/* Saved address+IE bit. */
281 
282 	/* Make sure clocking edge is down before starting... */
283 	portman_write_data(pm, 0);	/* Make sure edge is down. */
284 
285 	/* Set destination address to PCP. */
286 	cmdout = (port << 1) | INT_EN;	/* Address + IE + No Strobe. */
287 	portman_write_command(pm, cmdout);
288 
289 	while ((portman_read_status(pm) & ESTB) == ESTB)
290 		cpu_relax();	/* Wait for strobe echo. */
291 
292 	/* After the address lines settle, check multiplexed RxAvail signal.
293 	 * If data is available, read it.
294 	 */
295 	if ((portman_read_status(pm) & RXAVAIL) == 0)
296 		return -1;	/* No data. */
297 
298 	/* Set the Strobe signal to enable the Rx clocking circuitry. */
299 	portman_write_command(pm, cmdout | STROBE);	/* Write address+IE+Strobe. */
300 
301 	while ((portman_read_status(pm) & ESTB) == 0)
302 		cpu_relax(); /* Wait for strobe echo. */
303 
304 	/* The first data bit (msb) is already sitting on the input line. */
305 	midi_data = (portman_read_status(pm) & 128);
306 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
307 
308 	/* Data bit 6. */
309 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
310 	midi_data |= (portman_read_status(pm) >> 1) & 64;
311 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
312 
313 	/* Data bit 5. */
314 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
315 	midi_data |= (portman_read_status(pm) >> 2) & 32;
316 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
317 
318 	/* Data bit 4. */
319 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
320 	midi_data |= (portman_read_status(pm) >> 3) & 16;
321 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
322 
323 	/* Data bit 3. */
324 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
325 	midi_data |= (portman_read_status(pm) >> 4) & 8;
326 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
327 
328 	/* Data bit 2. */
329 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
330 	midi_data |= (portman_read_status(pm) >> 5) & 4;
331 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
332 
333 	/* Data bit 1. */
334 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
335 	midi_data |= (portman_read_status(pm) >> 6) & 2;
336 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
337 
338 	/* Data bit 0. */
339 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
340 	midi_data |= (portman_read_status(pm) >> 7) & 1;
341 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
342 	portman_write_data(pm, 0);	/* Return data clock low. */
343 
344 
345 	/* De-assert Strobe and return data. */
346 	portman_write_command(pm, cmdout);	/* Output saved address+IE. */
347 
348 	/* Wait for strobe echo. */
349 	while ((portman_read_status(pm) & ESTB) == ESTB)
350 		cpu_relax();
351 
352 	return (midi_data & 255);	/* Shift back and return value. */
353 }
354 
355 /*
356  *  Checks if any input data on the given channel is available
357  *  Checks RxAvail
358  */
359 static int portman_data_avail(struct portman *pm, int channel)
360 {
361 	int command = INT_EN;
362 	switch (channel) {
363 	case 0:
364 		command |= RXDATA0;
365 		break;
366 	case 1:
367 		command |= RXDATA1;
368 		break;
369 	}
370 	/* Write hardware (assumme STROBE=0) */
371 	portman_write_command(pm, command);
372 	/* Check multiplexed RxAvail signal */
373 	if ((portman_read_status(pm) & RXAVAIL) == RXAVAIL)
374 		return 1;	/* Data available */
375 
376 	/* No Data available */
377 	return 0;
378 }
379 
380 
381 /*
382  *  Flushes any input
383  */
384 static void portman_flush_input(struct portman *pm, unsigned char port)
385 {
386 	/* Local variable for counting things */
387 	unsigned int i = 0;
388 	unsigned char command = 0;
389 
390 	switch (port) {
391 	case 0:
392 		command = RXDATA0;
393 		break;
394 	case 1:
395 		command = RXDATA1;
396 		break;
397 	default:
398 		snd_printk(KERN_WARNING
399 			   "portman_flush_input() Won't flush port %i\n",
400 			   port);
401 		return;
402 	}
403 
404 	/* Set address for specified channel in port and allow to settle. */
405 	portman_write_command(pm, command);
406 
407 	/* Assert the Strobe and wait for echo back. */
408 	portman_write_command(pm, command | STROBE);
409 
410 	/* Wait for ESTB */
411 	while ((portman_read_status(pm) & ESTB) == 0)
412 		cpu_relax();
413 
414 	/* Output clock cycles to the Rx circuitry. */
415 	portman_write_data(pm, 0);
416 
417 	/* Flush 250 bits... */
418 	for (i = 0; i < 250; i++) {
419 		portman_write_data(pm, 1);
420 		portman_write_data(pm, 0);
421 	}
422 
423 	/* Deassert the Strobe signal of the port and wait for it to settle. */
424 	portman_write_command(pm, command | INT_EN);
425 
426 	/* Wait for settling */
427 	while ((portman_read_status(pm) & ESTB) == ESTB)
428 		cpu_relax();
429 }
430 
431 static int portman_probe(struct parport *p)
432 {
433 	/* Initialize the parallel port data register.  Will set Rx clocks
434 	 * low in case we happen to be addressing the Rx ports at this time.
435 	 */
436 	/* 1 */
437 	parport_write_data(p, 0);
438 
439 	/* Initialize the parallel port command register, thus initializing
440 	 * hardware handshake lines to midi box:
441 	 *
442 	 *                                  Strobe = 0
443 	 *                                  Interrupt Enable = 0
444 	 */
445 	/* 2 */
446 	parport_write_control(p, 0);
447 
448 	/* Check if Portman PC/P 2x4 is out there. */
449 	/* 3 */
450 	parport_write_control(p, RXDATA0);	/* Write Strobe=0 to command reg. */
451 
452 	/* Check for ESTB to be clear */
453 	/* 4 */
454 	if ((parport_read_status(p) & ESTB) == ESTB)
455 		return 1;	/* CODE 1 - Strobe Failure. */
456 
457 	/* Set for RXDATA0 where no damage will be done. */
458 	/* 5 */
459 	parport_write_control(p, RXDATA0 | STROBE);	/* Write Strobe=1 to command reg. */
460 
461 	/* 6 */
462 	if ((parport_read_status(p) & ESTB) != ESTB)
463 		return 1;	/* CODE 1 - Strobe Failure. */
464 
465 	/* 7 */
466 	parport_write_control(p, 0);	/* Reset Strobe=0. */
467 
468 	/* Check if Tx circuitry is functioning properly.  If initialized
469 	 * unit TxEmpty is false, send out char and see if it goes true.
470 	 */
471 	/* 8 */
472 	parport_write_control(p, TXDATA0);	/* Tx channel 0, strobe off. */
473 
474 	/* If PCP channel's TxEmpty is set (TxEmpty is read through the PP
475 	 * Status Register), then go write data.  Else go back and wait.
476 	 */
477 	/* 9 */
478 	if ((parport_read_status(p) & TXEMPTY) == 0)
479 		return 2;
480 
481 	/* Return OK status. */
482 	return 0;
483 }
484 
485 static int portman_device_init(struct portman *pm)
486 {
487 	portman_flush_input(pm, 0);
488 	portman_flush_input(pm, 1);
489 
490 	return 0;
491 }
492 
493 /*********************************************************************
494  * Rawmidi
495  *********************************************************************/
496 static int snd_portman_midi_open(struct snd_rawmidi_substream *substream)
497 {
498 	return 0;
499 }
500 
501 static int snd_portman_midi_close(struct snd_rawmidi_substream *substream)
502 {
503 	return 0;
504 }
505 
506 static void snd_portman_midi_input_trigger(struct snd_rawmidi_substream *substream,
507 					   int up)
508 {
509 	struct portman *pm = substream->rmidi->private_data;
510 	unsigned long flags;
511 
512 	spin_lock_irqsave(&pm->reg_lock, flags);
513 	if (up)
514 		pm->mode[substream->number] |= PORTMAN2X4_MODE_INPUT_TRIGGERED;
515 	else
516 		pm->mode[substream->number] &= ~PORTMAN2X4_MODE_INPUT_TRIGGERED;
517 	spin_unlock_irqrestore(&pm->reg_lock, flags);
518 }
519 
520 static void snd_portman_midi_output_trigger(struct snd_rawmidi_substream *substream,
521 					    int up)
522 {
523 	struct portman *pm = substream->rmidi->private_data;
524 	unsigned long flags;
525 	unsigned char byte;
526 
527 	spin_lock_irqsave(&pm->reg_lock, flags);
528 	if (up) {
529 		while ((snd_rawmidi_transmit(substream, &byte, 1) == 1))
530 			portman_write_midi(pm, substream->number, byte);
531 	}
532 	spin_unlock_irqrestore(&pm->reg_lock, flags);
533 }
534 
535 static const struct snd_rawmidi_ops snd_portman_midi_output = {
536 	.open =		snd_portman_midi_open,
537 	.close =	snd_portman_midi_close,
538 	.trigger =	snd_portman_midi_output_trigger,
539 };
540 
541 static const struct snd_rawmidi_ops snd_portman_midi_input = {
542 	.open =		snd_portman_midi_open,
543 	.close =	snd_portman_midi_close,
544 	.trigger =	snd_portman_midi_input_trigger,
545 };
546 
547 /* Create and initialize the rawmidi component */
548 static int snd_portman_rawmidi_create(struct snd_card *card)
549 {
550 	struct portman *pm = card->private_data;
551 	struct snd_rawmidi *rmidi;
552 	struct snd_rawmidi_substream *substream;
553 	int err;
554 
555 	err = snd_rawmidi_new(card, CARD_NAME, 0,
556 			      PORTMAN_NUM_OUTPUT_PORTS,
557 			      PORTMAN_NUM_INPUT_PORTS,
558 			      &rmidi);
559 	if (err < 0)
560 		return err;
561 
562 	rmidi->private_data = pm;
563 	strcpy(rmidi->name, CARD_NAME);
564 	rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
565 		            SNDRV_RAWMIDI_INFO_INPUT |
566                             SNDRV_RAWMIDI_INFO_DUPLEX;
567 
568 	pm->rmidi = rmidi;
569 
570 	/* register rawmidi ops */
571 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
572 			    &snd_portman_midi_output);
573 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
574 			    &snd_portman_midi_input);
575 
576 	/* name substreams */
577 	/* output */
578 	list_for_each_entry(substream,
579 			    &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams,
580 			    list) {
581 		sprintf(substream->name,
582 			"Portman2x4 %d", substream->number+1);
583 	}
584 	/* input */
585 	list_for_each_entry(substream,
586 			    &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams,
587 			    list) {
588 		pm->midi_input[substream->number] = substream;
589 		sprintf(substream->name,
590 			"Portman2x4 %d", substream->number+1);
591 	}
592 
593 	return err;
594 }
595 
596 /*********************************************************************
597  * parport stuff
598  *********************************************************************/
599 static void snd_portman_interrupt(void *userdata)
600 {
601 	unsigned char midivalue = 0;
602 	struct portman *pm = ((struct snd_card*)userdata)->private_data;
603 
604 	spin_lock(&pm->reg_lock);
605 
606 	/* While any input data is waiting */
607 	while ((portman_read_status(pm) & INT_REQ) == INT_REQ) {
608 		/* If data available on channel 0,
609 		   read it and stuff it into the queue. */
610 		if (portman_data_avail(pm, 0)) {
611 			/* Read Midi */
612 			midivalue = portman_read_midi(pm, 0);
613 			/* put midi into queue... */
614 			if (pm->mode[0] & PORTMAN2X4_MODE_INPUT_TRIGGERED)
615 				snd_rawmidi_receive(pm->midi_input[0],
616 						    &midivalue, 1);
617 
618 		}
619 		/* If data available on channel 1,
620 		   read it and stuff it into the queue. */
621 		if (portman_data_avail(pm, 1)) {
622 			/* Read Midi */
623 			midivalue = portman_read_midi(pm, 1);
624 			/* put midi into queue... */
625 			if (pm->mode[1] & PORTMAN2X4_MODE_INPUT_TRIGGERED)
626 				snd_rawmidi_receive(pm->midi_input[1],
627 						    &midivalue, 1);
628 		}
629 
630 	}
631 
632 	spin_unlock(&pm->reg_lock);
633 }
634 
635 static void snd_portman_attach(struct parport *p)
636 {
637 	struct platform_device *device;
638 
639 	device = platform_device_alloc(PLATFORM_DRIVER, device_count);
640 	if (!device)
641 		return;
642 
643 	/* Temporary assignment to forward the parport */
644 	platform_set_drvdata(device, p);
645 
646 	if (platform_device_add(device) < 0) {
647 		platform_device_put(device);
648 		return;
649 	}
650 
651 	/* Since we dont get the return value of probe
652 	 * We need to check if device probing succeeded or not */
653 	if (!platform_get_drvdata(device)) {
654 		platform_device_unregister(device);
655 		return;
656 	}
657 
658 	/* register device in global table */
659 	platform_devices[device_count] = device;
660 	device_count++;
661 }
662 
663 static void snd_portman_detach(struct parport *p)
664 {
665 	/* nothing to do here */
666 }
667 
668 static int snd_portman_dev_probe(struct pardevice *pardev)
669 {
670 	if (strcmp(pardev->name, DRIVER_NAME))
671 		return -ENODEV;
672 
673 	return 0;
674 }
675 
676 static struct parport_driver portman_parport_driver = {
677 	.name		= "portman2x4",
678 	.probe		= snd_portman_dev_probe,
679 	.match_port	= snd_portman_attach,
680 	.detach		= snd_portman_detach,
681 	.devmodel	= true,
682 };
683 
684 /*********************************************************************
685  * platform stuff
686  *********************************************************************/
687 static void snd_portman_card_private_free(struct snd_card *card)
688 {
689 	struct portman *pm = card->private_data;
690 	struct pardevice *pardev = pm->pardev;
691 
692 	if (pardev) {
693 		parport_release(pardev);
694 		parport_unregister_device(pardev);
695 	}
696 
697 	portman_free(pm);
698 }
699 
700 static int snd_portman_probe(struct platform_device *pdev)
701 {
702 	struct pardevice *pardev;
703 	struct parport *p;
704 	int dev = pdev->id;
705 	struct snd_card *card = NULL;
706 	struct portman *pm = NULL;
707 	int err;
708 	struct pardev_cb portman_cb = {
709 		.preempt = NULL,
710 		.wakeup = NULL,
711 		.irq_func = snd_portman_interrupt,	/* ISR */
712 		.flags = PARPORT_DEV_EXCL,		/* flags */
713 	};
714 
715 	p = platform_get_drvdata(pdev);
716 	platform_set_drvdata(pdev, NULL);
717 
718 	if (dev >= SNDRV_CARDS)
719 		return -ENODEV;
720 	if (!enable[dev])
721 		return -ENOENT;
722 
723 	err = snd_card_new(&pdev->dev, index[dev], id[dev], THIS_MODULE,
724 			   0, &card);
725 	if (err < 0) {
726 		snd_printd("Cannot create card\n");
727 		return err;
728 	}
729 	strcpy(card->driver, DRIVER_NAME);
730 	strcpy(card->shortname, CARD_NAME);
731 	sprintf(card->longname,  "%s at 0x%lx, irq %i",
732 		card->shortname, p->base, p->irq);
733 
734 	portman_cb.private = card;			   /* private */
735 	pardev = parport_register_dev_model(p,		   /* port */
736 					    DRIVER_NAME,   /* name */
737 					    &portman_cb,   /* callbacks */
738 					    pdev->id);	   /* device number */
739 	if (pardev == NULL) {
740 		snd_printd("Cannot register pardevice\n");
741 		err = -EIO;
742 		goto __err;
743 	}
744 
745 	/* claim parport */
746 	if (parport_claim(pardev)) {
747 		snd_printd("Cannot claim parport 0x%lx\n", pardev->port->base);
748 		err = -EIO;
749 		goto free_pardev;
750 	}
751 
752 	if ((err = portman_create(card, pardev, &pm)) < 0) {
753 		snd_printd("Cannot create main component\n");
754 		goto release_pardev;
755 	}
756 	card->private_data = pm;
757 	card->private_free = snd_portman_card_private_free;
758 
759 	err = portman_probe(p);
760 	if (err) {
761 		err = -EIO;
762 		goto __err;
763 	}
764 
765 	if ((err = snd_portman_rawmidi_create(card)) < 0) {
766 		snd_printd("Creating Rawmidi component failed\n");
767 		goto __err;
768 	}
769 
770 	/* init device */
771 	if ((err = portman_device_init(pm)) < 0)
772 		goto __err;
773 
774 	platform_set_drvdata(pdev, card);
775 
776 	/* At this point card will be usable */
777 	if ((err = snd_card_register(card)) < 0) {
778 		snd_printd("Cannot register card\n");
779 		goto __err;
780 	}
781 
782 	snd_printk(KERN_INFO "Portman 2x4 on 0x%lx\n", p->base);
783 	return 0;
784 
785 release_pardev:
786 	parport_release(pardev);
787 free_pardev:
788 	parport_unregister_device(pardev);
789 __err:
790 	snd_card_free(card);
791 	return err;
792 }
793 
794 static int snd_portman_remove(struct platform_device *pdev)
795 {
796 	struct snd_card *card = platform_get_drvdata(pdev);
797 
798 	if (card)
799 		snd_card_free(card);
800 
801 	return 0;
802 }
803 
804 
805 static struct platform_driver snd_portman_driver = {
806 	.probe  = snd_portman_probe,
807 	.remove = snd_portman_remove,
808 	.driver = {
809 		.name = PLATFORM_DRIVER,
810 	}
811 };
812 
813 /*********************************************************************
814  * module init stuff
815  *********************************************************************/
816 static void snd_portman_unregister_all(void)
817 {
818 	int i;
819 
820 	for (i = 0; i < SNDRV_CARDS; ++i) {
821 		if (platform_devices[i]) {
822 			platform_device_unregister(platform_devices[i]);
823 			platform_devices[i] = NULL;
824 		}
825 	}
826 	platform_driver_unregister(&snd_portman_driver);
827 	parport_unregister_driver(&portman_parport_driver);
828 }
829 
830 static int __init snd_portman_module_init(void)
831 {
832 	int err;
833 
834 	if ((err = platform_driver_register(&snd_portman_driver)) < 0)
835 		return err;
836 
837 	if (parport_register_driver(&portman_parport_driver) != 0) {
838 		platform_driver_unregister(&snd_portman_driver);
839 		return -EIO;
840 	}
841 
842 	if (device_count == 0) {
843 		snd_portman_unregister_all();
844 		return -ENODEV;
845 	}
846 
847 	return 0;
848 }
849 
850 static void __exit snd_portman_module_exit(void)
851 {
852 	snd_portman_unregister_all();
853 }
854 
855 module_init(snd_portman_module_init);
856 module_exit(snd_portman_module_exit);
857