xref: /linux/sound/drivers/portman2x4.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  *   Driver for Midiman Portman2x4 parallel port midi interface
3  *
4  *   Copyright (c) by Levent Guendogdu <levon@feature-it.com>
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19  *
20  * ChangeLog
21  * Jan 24 2007 Matthias Koenig <mkoenig@suse.de>
22  *      - cleanup and rewrite
23  * Sep 30 2004 Tobias Gehrig <tobias@gehrig.tk>
24  *      - source code cleanup
25  * Sep 03 2004 Tobias Gehrig <tobias@gehrig.tk>
26  *      - fixed compilation problem with alsa 1.0.6a (removed MODULE_CLASSES,
27  *        MODULE_PARM_SYNTAX and changed MODULE_DEVICES to
28  *        MODULE_SUPPORTED_DEVICE)
29  * Mar 24 2004 Tobias Gehrig <tobias@gehrig.tk>
30  *      - added 2.6 kernel support
31  * Mar 18 2004 Tobias Gehrig <tobias@gehrig.tk>
32  *      - added parport_unregister_driver to the startup routine if the driver fails to detect a portman
33  *      - added support for all 4 output ports in portman_putmidi
34  * Mar 17 2004 Tobias Gehrig <tobias@gehrig.tk>
35  *      - added checks for opened input device in interrupt handler
36  * Feb 20 2004 Tobias Gehrig <tobias@gehrig.tk>
37  *      - ported from alsa 0.5 to 1.0
38  */
39 
40 #include <linux/init.h>
41 #include <linux/platform_device.h>
42 #include <linux/parport.h>
43 #include <linux/spinlock.h>
44 #include <linux/delay.h>
45 #include <linux/slab.h>
46 #include <linux/module.h>
47 #include <sound/core.h>
48 #include <sound/initval.h>
49 #include <sound/rawmidi.h>
50 #include <sound/control.h>
51 
52 #define CARD_NAME "Portman 2x4"
53 #define DRIVER_NAME "portman"
54 #define PLATFORM_DRIVER "snd_portman2x4"
55 
56 static int index[SNDRV_CARDS]  = SNDRV_DEFAULT_IDX;
57 static char *id[SNDRV_CARDS]   = SNDRV_DEFAULT_STR;
58 static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;
59 
60 static struct platform_device *platform_devices[SNDRV_CARDS];
61 static int device_count;
62 
63 module_param_array(index, int, NULL, S_IRUGO);
64 MODULE_PARM_DESC(index, "Index value for " CARD_NAME " soundcard.");
65 module_param_array(id, charp, NULL, S_IRUGO);
66 MODULE_PARM_DESC(id, "ID string for " CARD_NAME " soundcard.");
67 module_param_array(enable, bool, NULL, S_IRUGO);
68 MODULE_PARM_DESC(enable, "Enable " CARD_NAME " soundcard.");
69 
70 MODULE_AUTHOR("Levent Guendogdu, Tobias Gehrig, Matthias Koenig");
71 MODULE_DESCRIPTION("Midiman Portman2x4");
72 MODULE_LICENSE("GPL");
73 MODULE_SUPPORTED_DEVICE("{{Midiman,Portman2x4}}");
74 
75 /*********************************************************************
76  * Chip specific
77  *********************************************************************/
78 #define PORTMAN_NUM_INPUT_PORTS 2
79 #define PORTMAN_NUM_OUTPUT_PORTS 4
80 
81 struct portman {
82 	spinlock_t reg_lock;
83 	struct snd_card *card;
84 	struct snd_rawmidi *rmidi;
85 	struct pardevice *pardev;
86 	int pardev_claimed;
87 
88 	int open_count;
89 	int mode[PORTMAN_NUM_INPUT_PORTS];
90 	struct snd_rawmidi_substream *midi_input[PORTMAN_NUM_INPUT_PORTS];
91 };
92 
93 static int portman_free(struct portman *pm)
94 {
95 	kfree(pm);
96 	return 0;
97 }
98 
99 static int portman_create(struct snd_card *card,
100 			  struct pardevice *pardev,
101 			  struct portman **rchip)
102 {
103 	struct portman *pm;
104 
105 	*rchip = NULL;
106 
107 	pm = kzalloc(sizeof(struct portman), GFP_KERNEL);
108 	if (pm == NULL)
109 		return -ENOMEM;
110 
111 	/* Init chip specific data */
112 	spin_lock_init(&pm->reg_lock);
113 	pm->card = card;
114 	pm->pardev = pardev;
115 
116 	*rchip = pm;
117 
118 	return 0;
119 }
120 
121 /*********************************************************************
122  * HW related constants
123  *********************************************************************/
124 
125 /* Standard PC parallel port status register equates. */
126 #define	PP_STAT_BSY   	0x80	/* Busy status.  Inverted. */
127 #define	PP_STAT_ACK   	0x40	/* Acknowledge.  Non-Inverted. */
128 #define	PP_STAT_POUT  	0x20	/* Paper Out.    Non-Inverted. */
129 #define	PP_STAT_SEL   	0x10	/* Select.       Non-Inverted. */
130 #define	PP_STAT_ERR   	0x08	/* Error.        Non-Inverted. */
131 
132 /* Standard PC parallel port command register equates. */
133 #define	PP_CMD_IEN  	0x10	/* IRQ Enable.   Non-Inverted. */
134 #define	PP_CMD_SELI 	0x08	/* Select Input. Inverted. */
135 #define	PP_CMD_INIT 	0x04	/* Init Printer. Non-Inverted. */
136 #define	PP_CMD_FEED 	0x02	/* Auto Feed.    Inverted. */
137 #define	PP_CMD_STB      0x01	/* Strobe.       Inverted. */
138 
139 /* Parallel Port Command Register as implemented by PCP2x4. */
140 #define	INT_EN	 	PP_CMD_IEN	/* Interrupt enable. */
141 #define	STROBE	        PP_CMD_STB	/* Command strobe. */
142 
143 /* The parallel port command register field (b1..b3) selects the
144  * various "registers" within the PC/P 2x4.  These are the internal
145  * address of these "registers" that must be written to the parallel
146  * port command register.
147  */
148 #define	RXDATA0		(0 << 1)	/* PCP RxData channel 0. */
149 #define	RXDATA1		(1 << 1)	/* PCP RxData channel 1. */
150 #define	GEN_CTL		(2 << 1)	/* PCP General Control Register. */
151 #define	SYNC_CTL 	(3 << 1)	/* PCP Sync Control Register. */
152 #define	TXDATA0		(4 << 1)	/* PCP TxData channel 0. */
153 #define	TXDATA1		(5 << 1)	/* PCP TxData channel 1. */
154 #define	TXDATA2		(6 << 1)	/* PCP TxData channel 2. */
155 #define	TXDATA3		(7 << 1)	/* PCP TxData channel 3. */
156 
157 /* Parallel Port Status Register as implemented by PCP2x4. */
158 #define	ESTB		PP_STAT_POUT	/* Echoed strobe. */
159 #define	INT_REQ         PP_STAT_ACK	/* Input data int request. */
160 #define	BUSY            PP_STAT_ERR	/* Interface Busy. */
161 
162 /* Parallel Port Status Register BUSY and SELECT lines are multiplexed
163  * between several functions.  Depending on which 2x4 "register" is
164  * currently selected (b1..b3), the BUSY and SELECT lines are
165  * assigned as follows:
166  *
167  *   SELECT LINE:                                                    A3 A2 A1
168  *                                                                   --------
169  */
170 #define	RXAVAIL		PP_STAT_SEL	/* Rx Available, channel 0.   0 0 0 */
171 //  RXAVAIL1    PP_STAT_SEL             /* Rx Available, channel 1.   0 0 1 */
172 #define	SYNC_STAT	PP_STAT_SEL	/* Reserved - Sync Status.    0 1 0 */
173 //                                      /* Reserved.                  0 1 1 */
174 #define	TXEMPTY		PP_STAT_SEL	/* Tx Empty, channel 0.       1 0 0 */
175 //      TXEMPTY1        PP_STAT_SEL     /* Tx Empty, channel 1.       1 0 1 */
176 //  TXEMPTY2    PP_STAT_SEL             /* Tx Empty, channel 2.       1 1 0 */
177 //  TXEMPTY3    PP_STAT_SEL             /* Tx Empty, channel 3.       1 1 1 */
178 
179 /*   BUSY LINE:                                                      A3 A2 A1
180  *                                                                   --------
181  */
182 #define	RXDATA		PP_STAT_BSY	/* Rx Input Data, channel 0.  0 0 0 */
183 //      RXDATA1         PP_STAT_BSY     /* Rx Input Data, channel 1.  0 0 1 */
184 #define	SYNC_DATA       PP_STAT_BSY	/* Reserved - Sync Data.      0 1 0 */
185 					/* Reserved.                  0 1 1 */
186 #define	DATA_ECHO       PP_STAT_BSY	/* Parallel Port Data Echo.   1 0 0 */
187 #define	A0_ECHO         PP_STAT_BSY	/* Address 0 Echo.            1 0 1 */
188 #define	A1_ECHO         PP_STAT_BSY	/* Address 1 Echo.            1 1 0 */
189 #define	A2_ECHO         PP_STAT_BSY	/* Address 2 Echo.            1 1 1 */
190 
191 #define PORTMAN2X4_MODE_INPUT_TRIGGERED	 0x01
192 
193 /*********************************************************************
194  * Hardware specific functions
195  *********************************************************************/
196 static inline void portman_write_command(struct portman *pm, u8 value)
197 {
198 	parport_write_control(pm->pardev->port, value);
199 }
200 
201 static inline u8 portman_read_command(struct portman *pm)
202 {
203 	return parport_read_control(pm->pardev->port);
204 }
205 
206 static inline u8 portman_read_status(struct portman *pm)
207 {
208 	return parport_read_status(pm->pardev->port);
209 }
210 
211 static inline u8 portman_read_data(struct portman *pm)
212 {
213 	return parport_read_data(pm->pardev->port);
214 }
215 
216 static inline void portman_write_data(struct portman *pm, u8 value)
217 {
218 	parport_write_data(pm->pardev->port, value);
219 }
220 
221 static void portman_write_midi(struct portman *pm,
222 			       int port, u8 mididata)
223 {
224 	int command = ((port + 4) << 1);
225 
226 	/* Get entering data byte and port number in BL and BH respectively.
227 	 * Set up Tx Channel address field for use with PP Cmd Register.
228 	 * Store address field in BH register.
229 	 * Inputs:      AH = Output port number (0..3).
230 	 *              AL = Data byte.
231 	 *    command = TXDATA0 | INT_EN;
232 	 * Align port num with address field (b1...b3),
233 	 * set address for TXDatax, Strobe=0
234 	 */
235 	command |= INT_EN;
236 
237 	/* Disable interrupts so that the process is not interrupted, then
238 	 * write the address associated with the current Tx channel to the
239 	 * PP Command Reg.  Do not set the Strobe signal yet.
240 	 */
241 
242 	do {
243 		portman_write_command(pm, command);
244 
245 		/* While the address lines settle, write parallel output data to
246 		 * PP Data Reg.  This has no effect until Strobe signal is asserted.
247 		 */
248 
249 		portman_write_data(pm, mididata);
250 
251 		/* If PCP channel's TxEmpty is set (TxEmpty is read through the PP
252 		 * Status Register), then go write data.  Else go back and wait.
253 		 */
254 	} while ((portman_read_status(pm) & TXEMPTY) != TXEMPTY);
255 
256 	/* TxEmpty is set.  Maintain PC/P destination address and assert
257 	 * Strobe through the PP Command Reg.  This will Strobe data into
258 	 * the PC/P transmitter and set the PC/P BUSY signal.
259 	 */
260 
261 	portman_write_command(pm, command | STROBE);
262 
263 	/* Wait for strobe line to settle and echo back through hardware.
264 	 * Once it has echoed back, assume that the address and data lines
265 	 * have settled!
266 	 */
267 
268 	while ((portman_read_status(pm) & ESTB) == 0)
269 		cpu_relax();
270 
271 	/* Release strobe and immediately re-allow interrupts. */
272 	portman_write_command(pm, command);
273 
274 	while ((portman_read_status(pm) & ESTB) == ESTB)
275 		cpu_relax();
276 
277 	/* PC/P BUSY is now set.  We must wait until BUSY resets itself.
278 	 * We'll reenable ints while we're waiting.
279 	 */
280 
281 	while ((portman_read_status(pm) & BUSY) == BUSY)
282 		cpu_relax();
283 
284 	/* Data sent. */
285 }
286 
287 
288 /*
289  *  Read MIDI byte from port
290  *  Attempt to read input byte from specified hardware input port (0..).
291  *  Return -1 if no data
292  */
293 static int portman_read_midi(struct portman *pm, int port)
294 {
295 	unsigned char midi_data = 0;
296 	unsigned char cmdout;	/* Saved address+IE bit. */
297 
298 	/* Make sure clocking edge is down before starting... */
299 	portman_write_data(pm, 0);	/* Make sure edge is down. */
300 
301 	/* Set destination address to PCP. */
302 	cmdout = (port << 1) | INT_EN;	/* Address + IE + No Strobe. */
303 	portman_write_command(pm, cmdout);
304 
305 	while ((portman_read_status(pm) & ESTB) == ESTB)
306 		cpu_relax();	/* Wait for strobe echo. */
307 
308 	/* After the address lines settle, check multiplexed RxAvail signal.
309 	 * If data is available, read it.
310 	 */
311 	if ((portman_read_status(pm) & RXAVAIL) == 0)
312 		return -1;	/* No data. */
313 
314 	/* Set the Strobe signal to enable the Rx clocking circuitry. */
315 	portman_write_command(pm, cmdout | STROBE);	/* Write address+IE+Strobe. */
316 
317 	while ((portman_read_status(pm) & ESTB) == 0)
318 		cpu_relax(); /* Wait for strobe echo. */
319 
320 	/* The first data bit (msb) is already sitting on the input line. */
321 	midi_data = (portman_read_status(pm) & 128);
322 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
323 
324 	/* Data bit 6. */
325 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
326 	midi_data |= (portman_read_status(pm) >> 1) & 64;
327 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
328 
329 	/* Data bit 5. */
330 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
331 	midi_data |= (portman_read_status(pm) >> 2) & 32;
332 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
333 
334 	/* Data bit 4. */
335 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
336 	midi_data |= (portman_read_status(pm) >> 3) & 16;
337 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
338 
339 	/* Data bit 3. */
340 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
341 	midi_data |= (portman_read_status(pm) >> 4) & 8;
342 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
343 
344 	/* Data bit 2. */
345 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
346 	midi_data |= (portman_read_status(pm) >> 5) & 4;
347 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
348 
349 	/* Data bit 1. */
350 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
351 	midi_data |= (portman_read_status(pm) >> 6) & 2;
352 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
353 
354 	/* Data bit 0. */
355 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
356 	midi_data |= (portman_read_status(pm) >> 7) & 1;
357 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
358 	portman_write_data(pm, 0);	/* Return data clock low. */
359 
360 
361 	/* De-assert Strobe and return data. */
362 	portman_write_command(pm, cmdout);	/* Output saved address+IE. */
363 
364 	/* Wait for strobe echo. */
365 	while ((portman_read_status(pm) & ESTB) == ESTB)
366 		cpu_relax();
367 
368 	return (midi_data & 255);	/* Shift back and return value. */
369 }
370 
371 /*
372  *  Checks if any input data on the given channel is available
373  *  Checks RxAvail
374  */
375 static int portman_data_avail(struct portman *pm, int channel)
376 {
377 	int command = INT_EN;
378 	switch (channel) {
379 	case 0:
380 		command |= RXDATA0;
381 		break;
382 	case 1:
383 		command |= RXDATA1;
384 		break;
385 	}
386 	/* Write hardware (assumme STROBE=0) */
387 	portman_write_command(pm, command);
388 	/* Check multiplexed RxAvail signal */
389 	if ((portman_read_status(pm) & RXAVAIL) == RXAVAIL)
390 		return 1;	/* Data available */
391 
392 	/* No Data available */
393 	return 0;
394 }
395 
396 
397 /*
398  *  Flushes any input
399  */
400 static void portman_flush_input(struct portman *pm, unsigned char port)
401 {
402 	/* Local variable for counting things */
403 	unsigned int i = 0;
404 	unsigned char command = 0;
405 
406 	switch (port) {
407 	case 0:
408 		command = RXDATA0;
409 		break;
410 	case 1:
411 		command = RXDATA1;
412 		break;
413 	default:
414 		snd_printk(KERN_WARNING
415 			   "portman_flush_input() Won't flush port %i\n",
416 			   port);
417 		return;
418 	}
419 
420 	/* Set address for specified channel in port and allow to settle. */
421 	portman_write_command(pm, command);
422 
423 	/* Assert the Strobe and wait for echo back. */
424 	portman_write_command(pm, command | STROBE);
425 
426 	/* Wait for ESTB */
427 	while ((portman_read_status(pm) & ESTB) == 0)
428 		cpu_relax();
429 
430 	/* Output clock cycles to the Rx circuitry. */
431 	portman_write_data(pm, 0);
432 
433 	/* Flush 250 bits... */
434 	for (i = 0; i < 250; i++) {
435 		portman_write_data(pm, 1);
436 		portman_write_data(pm, 0);
437 	}
438 
439 	/* Deassert the Strobe signal of the port and wait for it to settle. */
440 	portman_write_command(pm, command | INT_EN);
441 
442 	/* Wait for settling */
443 	while ((portman_read_status(pm) & ESTB) == ESTB)
444 		cpu_relax();
445 }
446 
447 static int portman_probe(struct parport *p)
448 {
449 	/* Initialize the parallel port data register.  Will set Rx clocks
450 	 * low in case we happen to be addressing the Rx ports at this time.
451 	 */
452 	/* 1 */
453 	parport_write_data(p, 0);
454 
455 	/* Initialize the parallel port command register, thus initializing
456 	 * hardware handshake lines to midi box:
457 	 *
458 	 *                                  Strobe = 0
459 	 *                                  Interrupt Enable = 0
460 	 */
461 	/* 2 */
462 	parport_write_control(p, 0);
463 
464 	/* Check if Portman PC/P 2x4 is out there. */
465 	/* 3 */
466 	parport_write_control(p, RXDATA0);	/* Write Strobe=0 to command reg. */
467 
468 	/* Check for ESTB to be clear */
469 	/* 4 */
470 	if ((parport_read_status(p) & ESTB) == ESTB)
471 		return 1;	/* CODE 1 - Strobe Failure. */
472 
473 	/* Set for RXDATA0 where no damage will be done. */
474 	/* 5 */
475 	parport_write_control(p, RXDATA0 + STROBE);	/* Write Strobe=1 to command reg. */
476 
477 	/* 6 */
478 	if ((parport_read_status(p) & ESTB) != ESTB)
479 		return 1;	/* CODE 1 - Strobe Failure. */
480 
481 	/* 7 */
482 	parport_write_control(p, 0);	/* Reset Strobe=0. */
483 
484 	/* Check if Tx circuitry is functioning properly.  If initialized
485 	 * unit TxEmpty is false, send out char and see if if goes true.
486 	 */
487 	/* 8 */
488 	parport_write_control(p, TXDATA0);	/* Tx channel 0, strobe off. */
489 
490 	/* If PCP channel's TxEmpty is set (TxEmpty is read through the PP
491 	 * Status Register), then go write data.  Else go back and wait.
492 	 */
493 	/* 9 */
494 	if ((parport_read_status(p) & TXEMPTY) == 0)
495 		return 2;
496 
497 	/* Return OK status. */
498 	return 0;
499 }
500 
501 static int portman_device_init(struct portman *pm)
502 {
503 	portman_flush_input(pm, 0);
504 	portman_flush_input(pm, 1);
505 
506 	return 0;
507 }
508 
509 /*********************************************************************
510  * Rawmidi
511  *********************************************************************/
512 static int snd_portman_midi_open(struct snd_rawmidi_substream *substream)
513 {
514 	return 0;
515 }
516 
517 static int snd_portman_midi_close(struct snd_rawmidi_substream *substream)
518 {
519 	return 0;
520 }
521 
522 static void snd_portman_midi_input_trigger(struct snd_rawmidi_substream *substream,
523 					   int up)
524 {
525 	struct portman *pm = substream->rmidi->private_data;
526 	unsigned long flags;
527 
528 	spin_lock_irqsave(&pm->reg_lock, flags);
529 	if (up)
530 		pm->mode[substream->number] |= PORTMAN2X4_MODE_INPUT_TRIGGERED;
531 	else
532 		pm->mode[substream->number] &= ~PORTMAN2X4_MODE_INPUT_TRIGGERED;
533 	spin_unlock_irqrestore(&pm->reg_lock, flags);
534 }
535 
536 static void snd_portman_midi_output_trigger(struct snd_rawmidi_substream *substream,
537 					    int up)
538 {
539 	struct portman *pm = substream->rmidi->private_data;
540 	unsigned long flags;
541 	unsigned char byte;
542 
543 	spin_lock_irqsave(&pm->reg_lock, flags);
544 	if (up) {
545 		while ((snd_rawmidi_transmit(substream, &byte, 1) == 1))
546 			portman_write_midi(pm, substream->number, byte);
547 	}
548 	spin_unlock_irqrestore(&pm->reg_lock, flags);
549 }
550 
551 static struct snd_rawmidi_ops snd_portman_midi_output = {
552 	.open =		snd_portman_midi_open,
553 	.close =	snd_portman_midi_close,
554 	.trigger =	snd_portman_midi_output_trigger,
555 };
556 
557 static struct snd_rawmidi_ops snd_portman_midi_input = {
558 	.open =		snd_portman_midi_open,
559 	.close =	snd_portman_midi_close,
560 	.trigger =	snd_portman_midi_input_trigger,
561 };
562 
563 /* Create and initialize the rawmidi component */
564 static int snd_portman_rawmidi_create(struct snd_card *card)
565 {
566 	struct portman *pm = card->private_data;
567 	struct snd_rawmidi *rmidi;
568 	struct snd_rawmidi_substream *substream;
569 	int err;
570 
571 	err = snd_rawmidi_new(card, CARD_NAME, 0,
572 			      PORTMAN_NUM_OUTPUT_PORTS,
573 			      PORTMAN_NUM_INPUT_PORTS,
574 			      &rmidi);
575 	if (err < 0)
576 		return err;
577 
578 	rmidi->private_data = pm;
579 	strcpy(rmidi->name, CARD_NAME);
580 	rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
581 		            SNDRV_RAWMIDI_INFO_INPUT |
582                             SNDRV_RAWMIDI_INFO_DUPLEX;
583 
584 	pm->rmidi = rmidi;
585 
586 	/* register rawmidi ops */
587 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
588 			    &snd_portman_midi_output);
589 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
590 			    &snd_portman_midi_input);
591 
592 	/* name substreams */
593 	/* output */
594 	list_for_each_entry(substream,
595 			    &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams,
596 			    list) {
597 		sprintf(substream->name,
598 			"Portman2x4 %d", substream->number+1);
599 	}
600 	/* input */
601 	list_for_each_entry(substream,
602 			    &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams,
603 			    list) {
604 		pm->midi_input[substream->number] = substream;
605 		sprintf(substream->name,
606 			"Portman2x4 %d", substream->number+1);
607 	}
608 
609 	return err;
610 }
611 
612 /*********************************************************************
613  * parport stuff
614  *********************************************************************/
615 static void snd_portman_interrupt(void *userdata)
616 {
617 	unsigned char midivalue = 0;
618 	struct portman *pm = ((struct snd_card*)userdata)->private_data;
619 
620 	spin_lock(&pm->reg_lock);
621 
622 	/* While any input data is waiting */
623 	while ((portman_read_status(pm) & INT_REQ) == INT_REQ) {
624 		/* If data available on channel 0,
625 		   read it and stuff it into the queue. */
626 		if (portman_data_avail(pm, 0)) {
627 			/* Read Midi */
628 			midivalue = portman_read_midi(pm, 0);
629 			/* put midi into queue... */
630 			if (pm->mode[0] & PORTMAN2X4_MODE_INPUT_TRIGGERED)
631 				snd_rawmidi_receive(pm->midi_input[0],
632 						    &midivalue, 1);
633 
634 		}
635 		/* If data available on channel 1,
636 		   read it and stuff it into the queue. */
637 		if (portman_data_avail(pm, 1)) {
638 			/* Read Midi */
639 			midivalue = portman_read_midi(pm, 1);
640 			/* put midi into queue... */
641 			if (pm->mode[1] & PORTMAN2X4_MODE_INPUT_TRIGGERED)
642 				snd_rawmidi_receive(pm->midi_input[1],
643 						    &midivalue, 1);
644 		}
645 
646 	}
647 
648 	spin_unlock(&pm->reg_lock);
649 }
650 
651 static int snd_portman_probe_port(struct parport *p)
652 {
653 	struct pardevice *pardev;
654 	int res;
655 
656 	pardev = parport_register_device(p, DRIVER_NAME,
657 					 NULL, NULL, NULL,
658 					 0, NULL);
659 	if (!pardev)
660 		return -EIO;
661 
662 	if (parport_claim(pardev)) {
663 		parport_unregister_device(pardev);
664 		return -EIO;
665 	}
666 
667 	res = portman_probe(p);
668 
669 	parport_release(pardev);
670 	parport_unregister_device(pardev);
671 
672 	return res ? -EIO : 0;
673 }
674 
675 static void snd_portman_attach(struct parport *p)
676 {
677 	struct platform_device *device;
678 
679 	device = platform_device_alloc(PLATFORM_DRIVER, device_count);
680 	if (!device)
681 		return;
682 
683 	/* Temporary assignment to forward the parport */
684 	platform_set_drvdata(device, p);
685 
686 	if (platform_device_add(device) < 0) {
687 		platform_device_put(device);
688 		return;
689 	}
690 
691 	/* Since we dont get the return value of probe
692 	 * We need to check if device probing succeeded or not */
693 	if (!platform_get_drvdata(device)) {
694 		platform_device_unregister(device);
695 		return;
696 	}
697 
698 	/* register device in global table */
699 	platform_devices[device_count] = device;
700 	device_count++;
701 }
702 
703 static void snd_portman_detach(struct parport *p)
704 {
705 	/* nothing to do here */
706 }
707 
708 static struct parport_driver portman_parport_driver = {
709 	.name   = "portman2x4",
710 	.attach = snd_portman_attach,
711 	.detach = snd_portman_detach
712 };
713 
714 /*********************************************************************
715  * platform stuff
716  *********************************************************************/
717 static void snd_portman_card_private_free(struct snd_card *card)
718 {
719 	struct portman *pm = card->private_data;
720 	struct pardevice *pardev = pm->pardev;
721 
722 	if (pardev) {
723 		if (pm->pardev_claimed)
724 			parport_release(pardev);
725 		parport_unregister_device(pardev);
726 	}
727 
728 	portman_free(pm);
729 }
730 
731 static int snd_portman_probe(struct platform_device *pdev)
732 {
733 	struct pardevice *pardev;
734 	struct parport *p;
735 	int dev = pdev->id;
736 	struct snd_card *card = NULL;
737 	struct portman *pm = NULL;
738 	int err;
739 
740 	p = platform_get_drvdata(pdev);
741 	platform_set_drvdata(pdev, NULL);
742 
743 	if (dev >= SNDRV_CARDS)
744 		return -ENODEV;
745 	if (!enable[dev])
746 		return -ENOENT;
747 
748 	if ((err = snd_portman_probe_port(p)) < 0)
749 		return err;
750 
751 	err = snd_card_new(&pdev->dev, index[dev], id[dev], THIS_MODULE,
752 			   0, &card);
753 	if (err < 0) {
754 		snd_printd("Cannot create card\n");
755 		return err;
756 	}
757 	strcpy(card->driver, DRIVER_NAME);
758 	strcpy(card->shortname, CARD_NAME);
759 	sprintf(card->longname,  "%s at 0x%lx, irq %i",
760 		card->shortname, p->base, p->irq);
761 
762 	pardev = parport_register_device(p,                     /* port */
763 					 DRIVER_NAME,           /* name */
764 					 NULL,                  /* preempt */
765 					 NULL,                  /* wakeup */
766 					 snd_portman_interrupt, /* ISR */
767 					 PARPORT_DEV_EXCL,      /* flags */
768 					 (void *)card);         /* private */
769 	if (pardev == NULL) {
770 		snd_printd("Cannot register pardevice\n");
771 		err = -EIO;
772 		goto __err;
773 	}
774 
775 	if ((err = portman_create(card, pardev, &pm)) < 0) {
776 		snd_printd("Cannot create main component\n");
777 		parport_unregister_device(pardev);
778 		goto __err;
779 	}
780 	card->private_data = pm;
781 	card->private_free = snd_portman_card_private_free;
782 
783 	if ((err = snd_portman_rawmidi_create(card)) < 0) {
784 		snd_printd("Creating Rawmidi component failed\n");
785 		goto __err;
786 	}
787 
788 	/* claim parport */
789 	if (parport_claim(pardev)) {
790 		snd_printd("Cannot claim parport 0x%lx\n", pardev->port->base);
791 		err = -EIO;
792 		goto __err;
793 	}
794 	pm->pardev_claimed = 1;
795 
796 	/* init device */
797 	if ((err = portman_device_init(pm)) < 0)
798 		goto __err;
799 
800 	platform_set_drvdata(pdev, card);
801 
802 	/* At this point card will be usable */
803 	if ((err = snd_card_register(card)) < 0) {
804 		snd_printd("Cannot register card\n");
805 		goto __err;
806 	}
807 
808 	snd_printk(KERN_INFO "Portman 2x4 on 0x%lx\n", p->base);
809 	return 0;
810 
811 __err:
812 	snd_card_free(card);
813 	return err;
814 }
815 
816 static int snd_portman_remove(struct platform_device *pdev)
817 {
818 	struct snd_card *card = platform_get_drvdata(pdev);
819 
820 	if (card)
821 		snd_card_free(card);
822 
823 	return 0;
824 }
825 
826 
827 static struct platform_driver snd_portman_driver = {
828 	.probe  = snd_portman_probe,
829 	.remove = snd_portman_remove,
830 	.driver = {
831 		.name = PLATFORM_DRIVER,
832 	}
833 };
834 
835 /*********************************************************************
836  * module init stuff
837  *********************************************************************/
838 static void snd_portman_unregister_all(void)
839 {
840 	int i;
841 
842 	for (i = 0; i < SNDRV_CARDS; ++i) {
843 		if (platform_devices[i]) {
844 			platform_device_unregister(platform_devices[i]);
845 			platform_devices[i] = NULL;
846 		}
847 	}
848 	platform_driver_unregister(&snd_portman_driver);
849 	parport_unregister_driver(&portman_parport_driver);
850 }
851 
852 static int __init snd_portman_module_init(void)
853 {
854 	int err;
855 
856 	if ((err = platform_driver_register(&snd_portman_driver)) < 0)
857 		return err;
858 
859 	if (parport_register_driver(&portman_parport_driver) != 0) {
860 		platform_driver_unregister(&snd_portman_driver);
861 		return -EIO;
862 	}
863 
864 	if (device_count == 0) {
865 		snd_portman_unregister_all();
866 		return -ENODEV;
867 	}
868 
869 	return 0;
870 }
871 
872 static void __exit snd_portman_module_exit(void)
873 {
874 	snd_portman_unregister_all();
875 }
876 
877 module_init(snd_portman_module_init);
878 module_exit(snd_portman_module_exit);
879