1 /*
2  *  Driver for the Conexant CX25821 PCIe bridge
3  *
4  *  Copyright (C) 2009 Conexant Systems Inc.
5  *  Authors  <shu.lin@conexant.com>, <hiep.huynh@conexant.com>
6  *	Based on SAA713x ALSA driver and CX88 driver
7  *
8  *   This program is free software; you can redistribute it and/or modify
9  *   it under the terms of the GNU General Public License as published by
10  *   the Free Software Foundation, version 2
11  *
12  *   This program is distributed in the hope that it will be useful,
13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *   GNU General Public License for more details.
16  *
17  *   You should have received a copy of the GNU General Public License
18  *   along with this program; if not, write to the Free Software
19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
20  *
21  */
22 
23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24 
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/device.h>
28 #include <linux/interrupt.h>
29 #include <linux/vmalloc.h>
30 #include <linux/dma-mapping.h>
31 #include <linux/pci.h>
32 #include <linux/slab.h>
33 
34 #include <linux/delay.h>
35 #include <sound/core.h>
36 #include <sound/pcm.h>
37 #include <sound/pcm_params.h>
38 #include <sound/control.h>
39 #include <sound/initval.h>
40 #include <sound/tlv.h>
41 
42 #include "cx25821.h"
43 #include "cx25821-reg.h"
44 
45 #define AUDIO_SRAM_CHANNEL	SRAM_CH08
46 
47 #define dprintk(level, fmt, arg...)				\
48 do {								\
49 	if (debug >= level)					\
50 		pr_info("%s/1: " fmt, chip->dev->name, ##arg);	\
51 } while (0)
52 #define dprintk_core(level, fmt, arg...)				\
53 do {									\
54 	if (debug >= level)						\
55 		printk(KERN_DEBUG "%s/1: " fmt, chip->dev->name, ##arg); \
56 } while (0)
57 
58 /****************************************************************************
59 	Data type declarations - Can be moded to a header file later
60  ****************************************************************************/
61 
62 static int devno;
63 
64 struct cx25821_audio_buffer {
65 	unsigned int bpl;
66 	struct btcx_riscmem risc;
67 	struct videobuf_dmabuf dma;
68 };
69 
70 struct cx25821_audio_dev {
71 	struct cx25821_dev *dev;
72 	struct cx25821_dmaqueue q;
73 
74 	/* pci i/o */
75 	struct pci_dev *pci;
76 
77 	/* audio controls */
78 	int irq;
79 
80 	struct snd_card *card;
81 
82 	unsigned long iobase;
83 	spinlock_t reg_lock;
84 	atomic_t count;
85 
86 	unsigned int dma_size;
87 	unsigned int period_size;
88 	unsigned int num_periods;
89 
90 	struct videobuf_dmabuf *dma_risc;
91 
92 	struct cx25821_audio_buffer *buf;
93 
94 	struct snd_pcm_substream *substream;
95 };
96 
97 
98 /****************************************************************************
99 			Module global static vars
100  ****************************************************************************/
101 
102 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
103 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
104 static bool enable[SNDRV_CARDS] = { 1, [1 ... (SNDRV_CARDS - 1)] = 1 };
105 
106 module_param_array(enable, bool, NULL, 0444);
107 MODULE_PARM_DESC(enable, "Enable cx25821 soundcard. default enabled.");
108 
109 module_param_array(index, int, NULL, 0444);
110 MODULE_PARM_DESC(index, "Index value for cx25821 capture interface(s).");
111 
112 /****************************************************************************
113 				Module macros
114  ****************************************************************************/
115 
116 MODULE_DESCRIPTION("ALSA driver module for cx25821 based capture cards");
117 MODULE_AUTHOR("Hiep Huynh");
118 MODULE_LICENSE("GPL");
119 MODULE_SUPPORTED_DEVICE("{{Conexant,25821}");	/* "{{Conexant,23881}," */
120 
121 static unsigned int debug;
122 module_param(debug, int, 0644);
123 MODULE_PARM_DESC(debug, "enable debug messages");
124 
125 /****************************************************************************
126 			Module specific funtions
127  ****************************************************************************/
128 /* Constants taken from cx88-reg.h */
129 #define AUD_INT_DN_RISCI1       (1 <<  0)
130 #define AUD_INT_UP_RISCI1       (1 <<  1)
131 #define AUD_INT_RDS_DN_RISCI1   (1 <<  2)
132 #define AUD_INT_DN_RISCI2       (1 <<  4)	/* yes, 3 is skipped */
133 #define AUD_INT_UP_RISCI2       (1 <<  5)
134 #define AUD_INT_RDS_DN_RISCI2   (1 <<  6)
135 #define AUD_INT_DN_SYNC         (1 << 12)
136 #define AUD_INT_UP_SYNC         (1 << 13)
137 #define AUD_INT_RDS_DN_SYNC     (1 << 14)
138 #define AUD_INT_OPC_ERR         (1 << 16)
139 #define AUD_INT_BER_IRQ         (1 << 20)
140 #define AUD_INT_MCHG_IRQ        (1 << 21)
141 #define GP_COUNT_CONTROL_RESET	0x3
142 
143 #define PCI_MSK_AUD_EXT   (1 <<  4)
144 #define PCI_MSK_AUD_INT   (1 <<  3)
145 /*
146  * BOARD Specific: Sets audio DMA
147  */
148 
149 static int _cx25821_start_audio_dma(struct cx25821_audio_dev *chip)
150 {
151 	struct cx25821_audio_buffer *buf = chip->buf;
152 	struct cx25821_dev *dev = chip->dev;
153 	const struct sram_channel *audio_ch =
154 	    &cx25821_sram_channels[AUDIO_SRAM_CHANNEL];
155 	u32 tmp = 0;
156 
157 	/* enable output on the GPIO 0 for the MCLK ADC (Audio) */
158 	cx25821_set_gpiopin_direction(chip->dev, 0, 0);
159 
160 	/* Make sure RISC/FIFO are off before changing FIFO/RISC settings */
161 	cx_clear(AUD_INT_DMA_CTL,
162 		 FLD_AUD_DST_A_RISC_EN | FLD_AUD_DST_A_FIFO_EN);
163 
164 	/* setup fifo + format - out channel */
165 	cx25821_sram_channel_setup_audio(chip->dev, audio_ch, buf->bpl,
166 					 buf->risc.dma);
167 
168 	/* sets bpl size */
169 	cx_write(AUD_A_LNGTH, buf->bpl);
170 
171 	/* reset counter */
172 	/* GP_COUNT_CONTROL_RESET = 0x3 */
173 	cx_write(AUD_A_GPCNT_CTL, GP_COUNT_CONTROL_RESET);
174 	atomic_set(&chip->count, 0);
175 
176 	/* Set the input mode to 16-bit */
177 	tmp = cx_read(AUD_A_CFG);
178 	cx_write(AUD_A_CFG, tmp | FLD_AUD_DST_PK_MODE | FLD_AUD_DST_ENABLE |
179 		 FLD_AUD_CLK_ENABLE);
180 
181 	/*
182 	pr_info("DEBUG: Start audio DMA, %d B/line, cmds_start(0x%x)= %d lines/FIFO, %d periods, %d byte buffer\n",
183 		buf->bpl, audio_ch->cmds_start,
184 		cx_read(audio_ch->cmds_start + 12)>>1,
185 		chip->num_periods, buf->bpl * chip->num_periods);
186 	*/
187 
188 	/* Enables corresponding bits at AUD_INT_STAT */
189 	cx_write(AUD_A_INT_MSK, FLD_AUD_DST_RISCI1 | FLD_AUD_DST_OF |
190 		 FLD_AUD_DST_SYNC | FLD_AUD_DST_OPC_ERR);
191 
192 	/* Clean any pending interrupt bits already set */
193 	cx_write(AUD_A_INT_STAT, ~0);
194 
195 	/* enable audio irqs */
196 	cx_set(PCI_INT_MSK, chip->dev->pci_irqmask | PCI_MSK_AUD_INT);
197 
198 	/* Turn on audio downstream fifo and risc enable 0x101 */
199 	tmp = cx_read(AUD_INT_DMA_CTL);
200 	cx_set(AUD_INT_DMA_CTL, tmp |
201 	       (FLD_AUD_DST_A_RISC_EN | FLD_AUD_DST_A_FIFO_EN));
202 
203 	mdelay(100);
204 	return 0;
205 }
206 
207 /*
208  * BOARD Specific: Resets audio DMA
209  */
210 static int _cx25821_stop_audio_dma(struct cx25821_audio_dev *chip)
211 {
212 	struct cx25821_dev *dev = chip->dev;
213 
214 	/* stop dma */
215 	cx_clear(AUD_INT_DMA_CTL,
216 		 FLD_AUD_DST_A_RISC_EN | FLD_AUD_DST_A_FIFO_EN);
217 
218 	/* disable irqs */
219 	cx_clear(PCI_INT_MSK, PCI_MSK_AUD_INT);
220 	cx_clear(AUD_A_INT_MSK, AUD_INT_OPC_ERR | AUD_INT_DN_SYNC |
221 		 AUD_INT_DN_RISCI2 | AUD_INT_DN_RISCI1);
222 
223 	return 0;
224 }
225 
226 #define MAX_IRQ_LOOP 50
227 
228 /*
229  * BOARD Specific: IRQ dma bits
230  */
231 static char *cx25821_aud_irqs[32] = {
232 	"dn_risci1", "up_risci1", "rds_dn_risc1",	/* 0-2 */
233 	NULL,						/* reserved */
234 	"dn_risci2", "up_risci2", "rds_dn_risc2",	/* 4-6 */
235 	NULL,						/* reserved */
236 	"dnf_of", "upf_uf", "rds_dnf_uf",		/* 8-10 */
237 	NULL,						/* reserved */
238 	"dn_sync", "up_sync", "rds_dn_sync",		/* 12-14 */
239 	NULL,						/* reserved */
240 	"opc_err", "par_err", "rip_err",		/* 16-18 */
241 	"pci_abort", "ber_irq", "mchg_irq"		/* 19-21 */
242 };
243 
244 /*
245  * BOARD Specific: Threats IRQ audio specific calls
246  */
247 static void cx25821_aud_irq(struct cx25821_audio_dev *chip, u32 status,
248 			    u32 mask)
249 {
250 	struct cx25821_dev *dev = chip->dev;
251 
252 	if (0 == (status & mask))
253 		return;
254 
255 	cx_write(AUD_A_INT_STAT, status);
256 	if (debug > 1 || (status & mask & ~0xff))
257 		cx25821_print_irqbits(dev->name, "irq aud", cx25821_aud_irqs,
258 				ARRAY_SIZE(cx25821_aud_irqs), status, mask);
259 
260 	/* risc op code error */
261 	if (status & AUD_INT_OPC_ERR) {
262 		pr_warn("WARNING %s/1: Audio risc op code error\n", dev->name);
263 
264 		cx_clear(AUD_INT_DMA_CTL,
265 			 FLD_AUD_DST_A_RISC_EN | FLD_AUD_DST_A_FIFO_EN);
266 		cx25821_sram_channel_dump_audio(dev,
267 				&cx25821_sram_channels[AUDIO_SRAM_CHANNEL]);
268 	}
269 	if (status & AUD_INT_DN_SYNC) {
270 		pr_warn("WARNING %s: Downstream sync error!\n", dev->name);
271 		cx_write(AUD_A_GPCNT_CTL, GP_COUNT_CONTROL_RESET);
272 		return;
273 	}
274 
275 	/* risc1 downstream */
276 	if (status & AUD_INT_DN_RISCI1) {
277 		atomic_set(&chip->count, cx_read(AUD_A_GPCNT));
278 		snd_pcm_period_elapsed(chip->substream);
279 	}
280 }
281 
282 /*
283  * BOARD Specific: Handles IRQ calls
284  */
285 static irqreturn_t cx25821_irq(int irq, void *dev_id)
286 {
287 	struct cx25821_audio_dev *chip = dev_id;
288 	struct cx25821_dev *dev = chip->dev;
289 	u32 status, pci_status;
290 	u32 audint_status, audint_mask;
291 	int loop, handled = 0;
292 
293 	audint_status = cx_read(AUD_A_INT_STAT);
294 	audint_mask = cx_read(AUD_A_INT_MSK);
295 	status = cx_read(PCI_INT_STAT);
296 
297 	for (loop = 0; loop < 1; loop++) {
298 		status = cx_read(PCI_INT_STAT);
299 		if (0 == status) {
300 			status = cx_read(PCI_INT_STAT);
301 			audint_status = cx_read(AUD_A_INT_STAT);
302 			audint_mask = cx_read(AUD_A_INT_MSK);
303 
304 			if (status) {
305 				handled = 1;
306 				cx_write(PCI_INT_STAT, status);
307 
308 				cx25821_aud_irq(chip, audint_status,
309 						audint_mask);
310 				break;
311 			} else {
312 				goto out;
313 			}
314 		}
315 
316 		handled = 1;
317 		cx_write(PCI_INT_STAT, status);
318 
319 		cx25821_aud_irq(chip, audint_status, audint_mask);
320 	}
321 
322 	pci_status = cx_read(PCI_INT_STAT);
323 
324 	if (handled)
325 		cx_write(PCI_INT_STAT, pci_status);
326 
327 out:
328 	return IRQ_RETVAL(handled);
329 }
330 
331 static int dsp_buffer_free(struct cx25821_audio_dev *chip)
332 {
333 	BUG_ON(!chip->dma_size);
334 
335 	dprintk(2, "Freeing buffer\n");
336 	videobuf_dma_unmap(&chip->pci->dev, chip->dma_risc);
337 	videobuf_dma_free(chip->dma_risc);
338 	btcx_riscmem_free(chip->pci, &chip->buf->risc);
339 	kfree(chip->buf);
340 
341 	chip->dma_risc = NULL;
342 	chip->dma_size = 0;
343 
344 	return 0;
345 }
346 
347 /****************************************************************************
348 				ALSA PCM Interface
349  ****************************************************************************/
350 
351 /*
352  * Digital hardware definition
353  */
354 #define DEFAULT_FIFO_SIZE	384
355 static struct snd_pcm_hardware snd_cx25821_digital_hw = {
356 	.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
357 		SNDRV_PCM_INFO_BLOCK_TRANSFER | SNDRV_PCM_INFO_MMAP_VALID,
358 	.formats = SNDRV_PCM_FMTBIT_S16_LE,
359 
360 	.rates = SNDRV_PCM_RATE_48000,
361 	.rate_min = 48000,
362 	.rate_max = 48000,
363 	.channels_min = 2,
364 	.channels_max = 2,
365 	/* Analog audio output will be full of clicks and pops if there
366 	   are not exactly four lines in the SRAM FIFO buffer.  */
367 	.period_bytes_min = DEFAULT_FIFO_SIZE / 3,
368 	.period_bytes_max = DEFAULT_FIFO_SIZE / 3,
369 	.periods_min = 1,
370 	.periods_max = AUDIO_LINE_SIZE,
371 	/* 128 * 128 = 16384 = 1024 * 16 */
372 	.buffer_bytes_max = (AUDIO_LINE_SIZE * AUDIO_LINE_SIZE),
373 };
374 
375 /*
376  * audio pcm capture open callback
377  */
378 static int snd_cx25821_pcm_open(struct snd_pcm_substream *substream)
379 {
380 	struct cx25821_audio_dev *chip = snd_pcm_substream_chip(substream);
381 	struct snd_pcm_runtime *runtime = substream->runtime;
382 	int err;
383 	unsigned int bpl = 0;
384 
385 	if (!chip) {
386 		pr_err("DEBUG: cx25821 can't find device struct. Can't proceed with open\n");
387 		return -ENODEV;
388 	}
389 
390 	err = snd_pcm_hw_constraint_pow2(runtime, 0,
391 					 SNDRV_PCM_HW_PARAM_PERIODS);
392 	if (err < 0)
393 		goto _error;
394 
395 	chip->substream = substream;
396 
397 	runtime->hw = snd_cx25821_digital_hw;
398 
399 	if (cx25821_sram_channels[AUDIO_SRAM_CHANNEL].fifo_size !=
400 	    DEFAULT_FIFO_SIZE) {
401 		/* since there are 3 audio Clusters */
402 		bpl = cx25821_sram_channels[AUDIO_SRAM_CHANNEL].fifo_size / 3;
403 		bpl &= ~7;	/* must be multiple of 8 */
404 
405 		if (bpl > AUDIO_LINE_SIZE)
406 			bpl = AUDIO_LINE_SIZE;
407 
408 		runtime->hw.period_bytes_min = bpl;
409 		runtime->hw.period_bytes_max = bpl;
410 	}
411 
412 	return 0;
413 _error:
414 	dprintk(1, "Error opening PCM!\n");
415 	return err;
416 }
417 
418 /*
419  * audio close callback
420  */
421 static int snd_cx25821_close(struct snd_pcm_substream *substream)
422 {
423 	return 0;
424 }
425 
426 /*
427  * hw_params callback
428  */
429 static int snd_cx25821_hw_params(struct snd_pcm_substream *substream,
430 				 struct snd_pcm_hw_params *hw_params)
431 {
432 	struct cx25821_audio_dev *chip = snd_pcm_substream_chip(substream);
433 	struct videobuf_dmabuf *dma;
434 
435 	struct cx25821_audio_buffer *buf;
436 	int ret;
437 
438 	if (substream->runtime->dma_area) {
439 		dsp_buffer_free(chip);
440 		substream->runtime->dma_area = NULL;
441 	}
442 
443 	chip->period_size = params_period_bytes(hw_params);
444 	chip->num_periods = params_periods(hw_params);
445 	chip->dma_size = chip->period_size * params_periods(hw_params);
446 
447 	BUG_ON(!chip->dma_size);
448 	BUG_ON(chip->num_periods & (chip->num_periods - 1));
449 
450 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
451 	if (NULL == buf)
452 		return -ENOMEM;
453 
454 	if (chip->period_size > AUDIO_LINE_SIZE)
455 		chip->period_size = AUDIO_LINE_SIZE;
456 
457 	buf->bpl = chip->period_size;
458 
459 	dma = &buf->dma;
460 	videobuf_dma_init(dma);
461 	ret = videobuf_dma_init_kernel(dma, PCI_DMA_FROMDEVICE,
462 			(PAGE_ALIGN(chip->dma_size) >> PAGE_SHIFT));
463 	if (ret < 0)
464 		goto error;
465 
466 	ret = videobuf_dma_map(&chip->pci->dev, dma);
467 	if (ret < 0)
468 		goto error;
469 
470 	ret = cx25821_risc_databuffer_audio(chip->pci, &buf->risc, dma->sglist,
471 			chip->period_size, chip->num_periods, 1);
472 	if (ret < 0) {
473 		pr_info("DEBUG: ERROR after cx25821_risc_databuffer_audio()\n");
474 		goto error;
475 	}
476 
477 	/* Loop back to start of program */
478 	buf->risc.jmp[0] = cpu_to_le32(RISC_JUMP | RISC_IRQ1 | RISC_CNT_INC);
479 	buf->risc.jmp[1] = cpu_to_le32(buf->risc.dma);
480 	buf->risc.jmp[2] = cpu_to_le32(0);	/* bits 63-32 */
481 
482 	chip->buf = buf;
483 	chip->dma_risc = dma;
484 
485 	substream->runtime->dma_area = chip->dma_risc->vaddr;
486 	substream->runtime->dma_bytes = chip->dma_size;
487 	substream->runtime->dma_addr = 0;
488 
489 	return 0;
490 
491 error:
492 	kfree(buf);
493 	return ret;
494 }
495 
496 /*
497  * hw free callback
498  */
499 static int snd_cx25821_hw_free(struct snd_pcm_substream *substream)
500 {
501 	struct cx25821_audio_dev *chip = snd_pcm_substream_chip(substream);
502 
503 	if (substream->runtime->dma_area) {
504 		dsp_buffer_free(chip);
505 		substream->runtime->dma_area = NULL;
506 	}
507 
508 	return 0;
509 }
510 
511 /*
512  * prepare callback
513  */
514 static int snd_cx25821_prepare(struct snd_pcm_substream *substream)
515 {
516 	return 0;
517 }
518 
519 /*
520  * trigger callback
521  */
522 static int snd_cx25821_card_trigger(struct snd_pcm_substream *substream,
523 				    int cmd)
524 {
525 	struct cx25821_audio_dev *chip = snd_pcm_substream_chip(substream);
526 	int err = 0;
527 
528 	/* Local interrupts are already disabled by ALSA */
529 	spin_lock(&chip->reg_lock);
530 
531 	switch (cmd) {
532 	case SNDRV_PCM_TRIGGER_START:
533 		err = _cx25821_start_audio_dma(chip);
534 		break;
535 	case SNDRV_PCM_TRIGGER_STOP:
536 		err = _cx25821_stop_audio_dma(chip);
537 		break;
538 	default:
539 		err = -EINVAL;
540 		break;
541 	}
542 
543 	spin_unlock(&chip->reg_lock);
544 
545 	return err;
546 }
547 
548 /*
549  * pointer callback
550  */
551 static snd_pcm_uframes_t snd_cx25821_pointer(struct snd_pcm_substream
552 					     *substream)
553 {
554 	struct cx25821_audio_dev *chip = snd_pcm_substream_chip(substream);
555 	struct snd_pcm_runtime *runtime = substream->runtime;
556 	u16 count;
557 
558 	count = atomic_read(&chip->count);
559 
560 	return runtime->period_size * (count & (runtime->periods - 1));
561 }
562 
563 /*
564  * page callback (needed for mmap)
565  */
566 static struct page *snd_cx25821_page(struct snd_pcm_substream *substream,
567 				     unsigned long offset)
568 {
569 	void *pageptr = substream->runtime->dma_area + offset;
570 
571 	return vmalloc_to_page(pageptr);
572 }
573 
574 /*
575  * operators
576  */
577 static struct snd_pcm_ops snd_cx25821_pcm_ops = {
578 	.open = snd_cx25821_pcm_open,
579 	.close = snd_cx25821_close,
580 	.ioctl = snd_pcm_lib_ioctl,
581 	.hw_params = snd_cx25821_hw_params,
582 	.hw_free = snd_cx25821_hw_free,
583 	.prepare = snd_cx25821_prepare,
584 	.trigger = snd_cx25821_card_trigger,
585 	.pointer = snd_cx25821_pointer,
586 	.page = snd_cx25821_page,
587 };
588 
589 /*
590  * ALSA create a PCM device:  Called when initializing the board.
591  * Sets up the name and hooks up the callbacks
592  */
593 static int snd_cx25821_pcm(struct cx25821_audio_dev *chip, int device,
594 			   char *name)
595 {
596 	struct snd_pcm *pcm;
597 	int err;
598 
599 	err = snd_pcm_new(chip->card, name, device, 0, 1, &pcm);
600 	if (err < 0) {
601 		pr_info("ERROR: FAILED snd_pcm_new() in %s\n", __func__);
602 		return err;
603 	}
604 	pcm->private_data = chip;
605 	pcm->info_flags = 0;
606 	strcpy(pcm->name, name);
607 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_cx25821_pcm_ops);
608 
609 	return 0;
610 }
611 
612 /****************************************************************************
613 			Basic Flow for Sound Devices
614  ****************************************************************************/
615 
616 /*
617  * PCI ID Table - 14f1:8801 and 14f1:8811 means function 1: Audio
618  * Only boards with eeprom and byte 1 at eeprom=1 have it
619  */
620 
621 static const struct pci_device_id cx25821_audio_pci_tbl[] = {
622 	{0x14f1, 0x0920, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
623 	{0,}
624 };
625 
626 MODULE_DEVICE_TABLE(pci, cx25821_audio_pci_tbl);
627 
628 /*
629  * Alsa Constructor - Component probe
630  */
631 static int cx25821_audio_initdev(struct cx25821_dev *dev)
632 {
633 	struct snd_card *card;
634 	struct cx25821_audio_dev *chip;
635 	int err;
636 
637 	if (devno >= SNDRV_CARDS) {
638 		pr_info("DEBUG ERROR: devno >= SNDRV_CARDS %s\n", __func__);
639 		return -ENODEV;
640 	}
641 
642 	if (!enable[devno]) {
643 		++devno;
644 		pr_info("DEBUG ERROR: !enable[devno] %s\n", __func__);
645 		return -ENOENT;
646 	}
647 
648 	err = snd_card_new(&dev->pci->dev, index[devno], id[devno],
649 			   THIS_MODULE,
650 			   sizeof(struct cx25821_audio_dev), &card);
651 	if (err < 0) {
652 		pr_info("DEBUG ERROR: cannot create snd_card_new in %s\n",
653 			__func__);
654 		return err;
655 	}
656 
657 	strcpy(card->driver, "cx25821");
658 
659 	/* Card "creation" */
660 	chip = card->private_data;
661 	spin_lock_init(&chip->reg_lock);
662 
663 	chip->dev = dev;
664 	chip->card = card;
665 	chip->pci = dev->pci;
666 	chip->iobase = pci_resource_start(dev->pci, 0);
667 
668 	chip->irq = dev->pci->irq;
669 
670 	err = request_irq(dev->pci->irq, cx25821_irq,
671 			  IRQF_SHARED, chip->dev->name, chip);
672 
673 	if (err < 0) {
674 		pr_err("ERROR %s: can't get IRQ %d for ALSA\n", chip->dev->name,
675 			dev->pci->irq);
676 		goto error;
677 	}
678 
679 	err = snd_cx25821_pcm(chip, 0, "cx25821 Digital");
680 	if (err < 0) {
681 		pr_info("DEBUG ERROR: cannot create snd_cx25821_pcm %s\n",
682 			__func__);
683 		goto error;
684 	}
685 
686 	strcpy(card->shortname, "cx25821");
687 	sprintf(card->longname, "%s at 0x%lx irq %d", chip->dev->name,
688 		chip->iobase, chip->irq);
689 	strcpy(card->mixername, "CX25821");
690 
691 	pr_info("%s/%i: ALSA support for cx25821 boards\n", card->driver,
692 		devno);
693 
694 	err = snd_card_register(card);
695 	if (err < 0) {
696 		pr_info("DEBUG ERROR: cannot register sound card %s\n",
697 			__func__);
698 		goto error;
699 	}
700 
701 	dev->card = card;
702 	devno++;
703 	return 0;
704 
705 error:
706 	snd_card_free(card);
707 	return err;
708 }
709 
710 /****************************************************************************
711 				LINUX MODULE INIT
712  ****************************************************************************/
713 
714 static int cx25821_alsa_exit_callback(struct device *dev, void *data)
715 {
716 	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
717 	struct cx25821_dev *cxdev = get_cx25821(v4l2_dev);
718 
719 	snd_card_free(cxdev->card);
720 	return 0;
721 }
722 
723 static void cx25821_audio_fini(void)
724 {
725 	struct device_driver *drv = driver_find("cx25821", &pci_bus_type);
726 	int ret;
727 
728 	ret = driver_for_each_device(drv, NULL, NULL, cx25821_alsa_exit_callback);
729 	if (ret)
730 		pr_err("%s failed to find a cx25821 driver.\n", __func__);
731 }
732 
733 static int cx25821_alsa_init_callback(struct device *dev, void *data)
734 {
735 	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
736 	struct cx25821_dev *cxdev = get_cx25821(v4l2_dev);
737 
738 	cx25821_audio_initdev(cxdev);
739 	return 0;
740 }
741 
742 /*
743  * Module initializer
744  *
745  * Loops through present saa7134 cards, and assigns an ALSA device
746  * to each one
747  *
748  */
749 static int cx25821_alsa_init(void)
750 {
751 	struct device_driver *drv = driver_find("cx25821", &pci_bus_type);
752 
753 	return driver_for_each_device(drv, NULL, NULL, cx25821_alsa_init_callback);
754 
755 }
756 
757 late_initcall(cx25821_alsa_init);
758 module_exit(cx25821_audio_fini);
759