xref: /linux/sound/drivers/portman2x4.c (revision 2697b79a469b68e3ad3640f55284359c1396278d)
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_status(struct portman *pm)
186 {
187 	return parport_read_status(pm->pardev->port);
188 }
189 
190 static inline void portman_write_data(struct portman *pm, u8 value)
191 {
192 	parport_write_data(pm->pardev->port, value);
193 }
194 
195 static void portman_write_midi(struct portman *pm,
196 			       int port, u8 mididata)
197 {
198 	int command = ((port + 4) << 1);
199 
200 	/* Get entering data byte and port number in BL and BH respectively.
201 	 * Set up Tx Channel address field for use with PP Cmd Register.
202 	 * Store address field in BH register.
203 	 * Inputs:      AH = Output port number (0..3).
204 	 *              AL = Data byte.
205 	 *    command = TXDATA0 | INT_EN;
206 	 * Align port num with address field (b1...b3),
207 	 * set address for TXDatax, Strobe=0
208 	 */
209 	command |= INT_EN;
210 
211 	/* Disable interrupts so that the process is not interrupted, then
212 	 * write the address associated with the current Tx channel to the
213 	 * PP Command Reg.  Do not set the Strobe signal yet.
214 	 */
215 
216 	do {
217 		portman_write_command(pm, command);
218 
219 		/* While the address lines settle, write parallel output data to
220 		 * PP Data Reg.  This has no effect until Strobe signal is asserted.
221 		 */
222 
223 		portman_write_data(pm, mididata);
224 
225 		/* If PCP channel's TxEmpty is set (TxEmpty is read through the PP
226 		 * Status Register), then go write data.  Else go back and wait.
227 		 */
228 	} while ((portman_read_status(pm) & TXEMPTY) != TXEMPTY);
229 
230 	/* TxEmpty is set.  Maintain PC/P destination address and assert
231 	 * Strobe through the PP Command Reg.  This will Strobe data into
232 	 * the PC/P transmitter and set the PC/P BUSY signal.
233 	 */
234 
235 	portman_write_command(pm, command | STROBE);
236 
237 	/* Wait for strobe line to settle and echo back through hardware.
238 	 * Once it has echoed back, assume that the address and data lines
239 	 * have settled!
240 	 */
241 
242 	while ((portman_read_status(pm) & ESTB) == 0)
243 		cpu_relax();
244 
245 	/* Release strobe and immediately re-allow interrupts. */
246 	portman_write_command(pm, command);
247 
248 	while ((portman_read_status(pm) & ESTB) == ESTB)
249 		cpu_relax();
250 
251 	/* PC/P BUSY is now set.  We must wait until BUSY resets itself.
252 	 * We'll reenable ints while we're waiting.
253 	 */
254 
255 	while ((portman_read_status(pm) & BUSY) == BUSY)
256 		cpu_relax();
257 
258 	/* Data sent. */
259 }
260 
261 
262 /*
263  *  Read MIDI byte from port
264  *  Attempt to read input byte from specified hardware input port (0..).
265  *  Return -1 if no data
266  */
267 static int portman_read_midi(struct portman *pm, int port)
268 {
269 	unsigned char midi_data = 0;
270 	unsigned char cmdout;	/* Saved address+IE bit. */
271 
272 	/* Make sure clocking edge is down before starting... */
273 	portman_write_data(pm, 0);	/* Make sure edge is down. */
274 
275 	/* Set destination address to PCP. */
276 	cmdout = (port << 1) | INT_EN;	/* Address + IE + No Strobe. */
277 	portman_write_command(pm, cmdout);
278 
279 	while ((portman_read_status(pm) & ESTB) == ESTB)
280 		cpu_relax();	/* Wait for strobe echo. */
281 
282 	/* After the address lines settle, check multiplexed RxAvail signal.
283 	 * If data is available, read it.
284 	 */
285 	if ((portman_read_status(pm) & RXAVAIL) == 0)
286 		return -1;	/* No data. */
287 
288 	/* Set the Strobe signal to enable the Rx clocking circuitry. */
289 	portman_write_command(pm, cmdout | STROBE);	/* Write address+IE+Strobe. */
290 
291 	while ((portman_read_status(pm) & ESTB) == 0)
292 		cpu_relax(); /* Wait for strobe echo. */
293 
294 	/* The first data bit (msb) is already sitting on the input line. */
295 	midi_data = (portman_read_status(pm) & 128);
296 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
297 
298 	/* Data bit 6. */
299 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
300 	midi_data |= (portman_read_status(pm) >> 1) & 64;
301 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
302 
303 	/* Data bit 5. */
304 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
305 	midi_data |= (portman_read_status(pm) >> 2) & 32;
306 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
307 
308 	/* Data bit 4. */
309 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
310 	midi_data |= (portman_read_status(pm) >> 3) & 16;
311 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
312 
313 	/* Data bit 3. */
314 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
315 	midi_data |= (portman_read_status(pm) >> 4) & 8;
316 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
317 
318 	/* Data bit 2. */
319 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
320 	midi_data |= (portman_read_status(pm) >> 5) & 4;
321 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
322 
323 	/* Data bit 1. */
324 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
325 	midi_data |= (portman_read_status(pm) >> 6) & 2;
326 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
327 
328 	/* Data bit 0. */
329 	portman_write_data(pm, 0);	/* Cause falling edge while data settles. */
330 	midi_data |= (portman_read_status(pm) >> 7) & 1;
331 	portman_write_data(pm, 1);	/* Cause rising edge, which shifts data. */
332 	portman_write_data(pm, 0);	/* Return data clock low. */
333 
334 
335 	/* De-assert Strobe and return data. */
336 	portman_write_command(pm, cmdout);	/* Output saved address+IE. */
337 
338 	/* Wait for strobe echo. */
339 	while ((portman_read_status(pm) & ESTB) == ESTB)
340 		cpu_relax();
341 
342 	return (midi_data & 255);	/* Shift back and return value. */
343 }
344 
345 /*
346  *  Checks if any input data on the given channel is available
347  *  Checks RxAvail
348  */
349 static int portman_data_avail(struct portman *pm, int channel)
350 {
351 	int command = INT_EN;
352 	switch (channel) {
353 	case 0:
354 		command |= RXDATA0;
355 		break;
356 	case 1:
357 		command |= RXDATA1;
358 		break;
359 	}
360 	/* Write hardware (assumme STROBE=0) */
361 	portman_write_command(pm, command);
362 	/* Check multiplexed RxAvail signal */
363 	if ((portman_read_status(pm) & RXAVAIL) == RXAVAIL)
364 		return 1;	/* Data available */
365 
366 	/* No Data available */
367 	return 0;
368 }
369 
370 
371 /*
372  *  Flushes any input
373  */
374 static void portman_flush_input(struct portman *pm, unsigned char port)
375 {
376 	/* Local variable for counting things */
377 	unsigned int i = 0;
378 	unsigned char command = 0;
379 
380 	switch (port) {
381 	case 0:
382 		command = RXDATA0;
383 		break;
384 	case 1:
385 		command = RXDATA1;
386 		break;
387 	default:
388 		snd_printk(KERN_WARNING
389 			   "portman_flush_input() Won't flush port %i\n",
390 			   port);
391 		return;
392 	}
393 
394 	/* Set address for specified channel in port and allow to settle. */
395 	portman_write_command(pm, command);
396 
397 	/* Assert the Strobe and wait for echo back. */
398 	portman_write_command(pm, command | STROBE);
399 
400 	/* Wait for ESTB */
401 	while ((portman_read_status(pm) & ESTB) == 0)
402 		cpu_relax();
403 
404 	/* Output clock cycles to the Rx circuitry. */
405 	portman_write_data(pm, 0);
406 
407 	/* Flush 250 bits... */
408 	for (i = 0; i < 250; i++) {
409 		portman_write_data(pm, 1);
410 		portman_write_data(pm, 0);
411 	}
412 
413 	/* Deassert the Strobe signal of the port and wait for it to settle. */
414 	portman_write_command(pm, command | INT_EN);
415 
416 	/* Wait for settling */
417 	while ((portman_read_status(pm) & ESTB) == ESTB)
418 		cpu_relax();
419 }
420 
421 static int portman_probe(struct parport *p)
422 {
423 	/* Initialize the parallel port data register.  Will set Rx clocks
424 	 * low in case we happen to be addressing the Rx ports at this time.
425 	 */
426 	/* 1 */
427 	parport_write_data(p, 0);
428 
429 	/* Initialize the parallel port command register, thus initializing
430 	 * hardware handshake lines to midi box:
431 	 *
432 	 *                                  Strobe = 0
433 	 *                                  Interrupt Enable = 0
434 	 */
435 	/* 2 */
436 	parport_write_control(p, 0);
437 
438 	/* Check if Portman PC/P 2x4 is out there. */
439 	/* 3 */
440 	parport_write_control(p, RXDATA0);	/* Write Strobe=0 to command reg. */
441 
442 	/* Check for ESTB to be clear */
443 	/* 4 */
444 	if ((parport_read_status(p) & ESTB) == ESTB)
445 		return 1;	/* CODE 1 - Strobe Failure. */
446 
447 	/* Set for RXDATA0 where no damage will be done. */
448 	/* 5 */
449 	parport_write_control(p, RXDATA0 | STROBE);	/* Write Strobe=1 to command reg. */
450 
451 	/* 6 */
452 	if ((parport_read_status(p) & ESTB) != ESTB)
453 		return 1;	/* CODE 1 - Strobe Failure. */
454 
455 	/* 7 */
456 	parport_write_control(p, 0);	/* Reset Strobe=0. */
457 
458 	/* Check if Tx circuitry is functioning properly.  If initialized
459 	 * unit TxEmpty is false, send out char and see if it goes true.
460 	 */
461 	/* 8 */
462 	parport_write_control(p, TXDATA0);	/* Tx channel 0, strobe off. */
463 
464 	/* If PCP channel's TxEmpty is set (TxEmpty is read through the PP
465 	 * Status Register), then go write data.  Else go back and wait.
466 	 */
467 	/* 9 */
468 	if ((parport_read_status(p) & TXEMPTY) == 0)
469 		return 2;
470 
471 	/* Return OK status. */
472 	return 0;
473 }
474 
475 static int portman_device_init(struct portman *pm)
476 {
477 	portman_flush_input(pm, 0);
478 	portman_flush_input(pm, 1);
479 
480 	return 0;
481 }
482 
483 /*********************************************************************
484  * Rawmidi
485  *********************************************************************/
486 static int snd_portman_midi_open(struct snd_rawmidi_substream *substream)
487 {
488 	return 0;
489 }
490 
491 static int snd_portman_midi_close(struct snd_rawmidi_substream *substream)
492 {
493 	return 0;
494 }
495 
496 static void snd_portman_midi_input_trigger(struct snd_rawmidi_substream *substream,
497 					   int up)
498 {
499 	struct portman *pm = substream->rmidi->private_data;
500 	unsigned long flags;
501 
502 	spin_lock_irqsave(&pm->reg_lock, flags);
503 	if (up)
504 		pm->mode[substream->number] |= PORTMAN2X4_MODE_INPUT_TRIGGERED;
505 	else
506 		pm->mode[substream->number] &= ~PORTMAN2X4_MODE_INPUT_TRIGGERED;
507 	spin_unlock_irqrestore(&pm->reg_lock, flags);
508 }
509 
510 static void snd_portman_midi_output_trigger(struct snd_rawmidi_substream *substream,
511 					    int up)
512 {
513 	struct portman *pm = substream->rmidi->private_data;
514 	unsigned long flags;
515 	unsigned char byte;
516 
517 	spin_lock_irqsave(&pm->reg_lock, flags);
518 	if (up) {
519 		while ((snd_rawmidi_transmit(substream, &byte, 1) == 1))
520 			portman_write_midi(pm, substream->number, byte);
521 	}
522 	spin_unlock_irqrestore(&pm->reg_lock, flags);
523 }
524 
525 static const struct snd_rawmidi_ops snd_portman_midi_output = {
526 	.open =		snd_portman_midi_open,
527 	.close =	snd_portman_midi_close,
528 	.trigger =	snd_portman_midi_output_trigger,
529 };
530 
531 static const struct snd_rawmidi_ops snd_portman_midi_input = {
532 	.open =		snd_portman_midi_open,
533 	.close =	snd_portman_midi_close,
534 	.trigger =	snd_portman_midi_input_trigger,
535 };
536 
537 /* Create and initialize the rawmidi component */
538 static int snd_portman_rawmidi_create(struct snd_card *card)
539 {
540 	struct portman *pm = card->private_data;
541 	struct snd_rawmidi *rmidi;
542 	struct snd_rawmidi_substream *substream;
543 	int err;
544 
545 	err = snd_rawmidi_new(card, CARD_NAME, 0,
546 			      PORTMAN_NUM_OUTPUT_PORTS,
547 			      PORTMAN_NUM_INPUT_PORTS,
548 			      &rmidi);
549 	if (err < 0)
550 		return err;
551 
552 	rmidi->private_data = pm;
553 	strcpy(rmidi->name, CARD_NAME);
554 	rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
555 		            SNDRV_RAWMIDI_INFO_INPUT |
556                             SNDRV_RAWMIDI_INFO_DUPLEX;
557 
558 	pm->rmidi = rmidi;
559 
560 	/* register rawmidi ops */
561 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
562 			    &snd_portman_midi_output);
563 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
564 			    &snd_portman_midi_input);
565 
566 	/* name substreams */
567 	/* output */
568 	list_for_each_entry(substream,
569 			    &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams,
570 			    list) {
571 		sprintf(substream->name,
572 			"Portman2x4 %d", substream->number+1);
573 	}
574 	/* input */
575 	list_for_each_entry(substream,
576 			    &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams,
577 			    list) {
578 		pm->midi_input[substream->number] = substream;
579 		sprintf(substream->name,
580 			"Portman2x4 %d", substream->number+1);
581 	}
582 
583 	return err;
584 }
585 
586 /*********************************************************************
587  * parport stuff
588  *********************************************************************/
589 static void snd_portman_interrupt(void *userdata)
590 {
591 	unsigned char midivalue = 0;
592 	struct portman *pm = ((struct snd_card*)userdata)->private_data;
593 
594 	spin_lock(&pm->reg_lock);
595 
596 	/* While any input data is waiting */
597 	while ((portman_read_status(pm) & INT_REQ) == INT_REQ) {
598 		/* If data available on channel 0,
599 		   read it and stuff it into the queue. */
600 		if (portman_data_avail(pm, 0)) {
601 			/* Read Midi */
602 			midivalue = portman_read_midi(pm, 0);
603 			/* put midi into queue... */
604 			if (pm->mode[0] & PORTMAN2X4_MODE_INPUT_TRIGGERED)
605 				snd_rawmidi_receive(pm->midi_input[0],
606 						    &midivalue, 1);
607 
608 		}
609 		/* If data available on channel 1,
610 		   read it and stuff it into the queue. */
611 		if (portman_data_avail(pm, 1)) {
612 			/* Read Midi */
613 			midivalue = portman_read_midi(pm, 1);
614 			/* put midi into queue... */
615 			if (pm->mode[1] & PORTMAN2X4_MODE_INPUT_TRIGGERED)
616 				snd_rawmidi_receive(pm->midi_input[1],
617 						    &midivalue, 1);
618 		}
619 
620 	}
621 
622 	spin_unlock(&pm->reg_lock);
623 }
624 
625 static void snd_portman_attach(struct parport *p)
626 {
627 	struct platform_device *device;
628 
629 	device = platform_device_alloc(PLATFORM_DRIVER, device_count);
630 	if (!device)
631 		return;
632 
633 	/* Temporary assignment to forward the parport */
634 	platform_set_drvdata(device, p);
635 
636 	if (platform_device_add(device) < 0) {
637 		platform_device_put(device);
638 		return;
639 	}
640 
641 	/* Since we dont get the return value of probe
642 	 * We need to check if device probing succeeded or not */
643 	if (!platform_get_drvdata(device)) {
644 		platform_device_unregister(device);
645 		return;
646 	}
647 
648 	/* register device in global table */
649 	platform_devices[device_count] = device;
650 	device_count++;
651 }
652 
653 static void snd_portman_detach(struct parport *p)
654 {
655 	/* nothing to do here */
656 }
657 
658 static int snd_portman_dev_probe(struct pardevice *pardev)
659 {
660 	if (strcmp(pardev->name, DRIVER_NAME))
661 		return -ENODEV;
662 
663 	return 0;
664 }
665 
666 static struct parport_driver portman_parport_driver = {
667 	.name		= "portman2x4",
668 	.probe		= snd_portman_dev_probe,
669 	.match_port	= snd_portman_attach,
670 	.detach		= snd_portman_detach,
671 	.devmodel	= true,
672 };
673 
674 /*********************************************************************
675  * platform stuff
676  *********************************************************************/
677 static void snd_portman_card_private_free(struct snd_card *card)
678 {
679 	struct portman *pm = card->private_data;
680 	struct pardevice *pardev = pm->pardev;
681 
682 	if (pardev) {
683 		parport_release(pardev);
684 		parport_unregister_device(pardev);
685 	}
686 
687 	portman_free(pm);
688 }
689 
690 static int snd_portman_probe(struct platform_device *pdev)
691 {
692 	struct pardevice *pardev;
693 	struct parport *p;
694 	int dev = pdev->id;
695 	struct snd_card *card = NULL;
696 	struct portman *pm = NULL;
697 	int err;
698 	struct pardev_cb portman_cb = {
699 		.preempt = NULL,
700 		.wakeup = NULL,
701 		.irq_func = snd_portman_interrupt,	/* ISR */
702 		.flags = PARPORT_DEV_EXCL,		/* flags */
703 	};
704 
705 	p = platform_get_drvdata(pdev);
706 	platform_set_drvdata(pdev, NULL);
707 
708 	if (dev >= SNDRV_CARDS)
709 		return -ENODEV;
710 	if (!enable[dev])
711 		return -ENOENT;
712 
713 	err = snd_card_new(&pdev->dev, index[dev], id[dev], THIS_MODULE,
714 			   0, &card);
715 	if (err < 0) {
716 		snd_printd("Cannot create card\n");
717 		return err;
718 	}
719 	strcpy(card->driver, DRIVER_NAME);
720 	strcpy(card->shortname, CARD_NAME);
721 	sprintf(card->longname,  "%s at 0x%lx, irq %i",
722 		card->shortname, p->base, p->irq);
723 
724 	portman_cb.private = card;			   /* private */
725 	pardev = parport_register_dev_model(p,		   /* port */
726 					    DRIVER_NAME,   /* name */
727 					    &portman_cb,   /* callbacks */
728 					    pdev->id);	   /* device number */
729 	if (pardev == NULL) {
730 		snd_printd("Cannot register pardevice\n");
731 		err = -EIO;
732 		goto __err;
733 	}
734 
735 	/* claim parport */
736 	if (parport_claim(pardev)) {
737 		snd_printd("Cannot claim parport 0x%lx\n", pardev->port->base);
738 		err = -EIO;
739 		goto free_pardev;
740 	}
741 
742 	err = portman_create(card, pardev, &pm);
743 	if (err < 0) {
744 		snd_printd("Cannot create main component\n");
745 		goto release_pardev;
746 	}
747 	card->private_data = pm;
748 	card->private_free = snd_portman_card_private_free;
749 
750 	err = portman_probe(p);
751 	if (err) {
752 		err = -EIO;
753 		goto __err;
754 	}
755 
756 	err = snd_portman_rawmidi_create(card);
757 	if (err < 0) {
758 		snd_printd("Creating Rawmidi component failed\n");
759 		goto __err;
760 	}
761 
762 	/* init device */
763 	err = portman_device_init(pm);
764 	if (err < 0)
765 		goto __err;
766 
767 	platform_set_drvdata(pdev, card);
768 
769 	/* At this point card will be usable */
770 	err = snd_card_register(card);
771 	if (err < 0) {
772 		snd_printd("Cannot register card\n");
773 		goto __err;
774 	}
775 
776 	snd_printk(KERN_INFO "Portman 2x4 on 0x%lx\n", p->base);
777 	return 0;
778 
779 release_pardev:
780 	parport_release(pardev);
781 free_pardev:
782 	parport_unregister_device(pardev);
783 __err:
784 	snd_card_free(card);
785 	return err;
786 }
787 
788 static void snd_portman_remove(struct platform_device *pdev)
789 {
790 	struct snd_card *card = platform_get_drvdata(pdev);
791 
792 	if (card)
793 		snd_card_free(card);
794 }
795 
796 
797 static struct platform_driver snd_portman_driver = {
798 	.probe  = snd_portman_probe,
799 	.remove_new = snd_portman_remove,
800 	.driver = {
801 		.name = PLATFORM_DRIVER,
802 	}
803 };
804 
805 /*********************************************************************
806  * module init stuff
807  *********************************************************************/
808 static void snd_portman_unregister_all(void)
809 {
810 	int i;
811 
812 	for (i = 0; i < SNDRV_CARDS; ++i) {
813 		if (platform_devices[i]) {
814 			platform_device_unregister(platform_devices[i]);
815 			platform_devices[i] = NULL;
816 		}
817 	}
818 	platform_driver_unregister(&snd_portman_driver);
819 	parport_unregister_driver(&portman_parport_driver);
820 }
821 
822 static int __init snd_portman_module_init(void)
823 {
824 	int err;
825 
826 	err = platform_driver_register(&snd_portman_driver);
827 	if (err < 0)
828 		return err;
829 
830 	if (parport_register_driver(&portman_parport_driver) != 0) {
831 		platform_driver_unregister(&snd_portman_driver);
832 		return -EIO;
833 	}
834 
835 	if (device_count == 0) {
836 		snd_portman_unregister_all();
837 		return -ENODEV;
838 	}
839 
840 	return 0;
841 }
842 
843 static void __exit snd_portman_module_exit(void)
844 {
845 	snd_portman_unregister_all();
846 }
847 
848 module_init(snd_portman_module_init);
849 module_exit(snd_portman_module_exit);
850