1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Driver for the Conexant CX25821 PCIe bridge
4  *
5  *  Copyright (C) 2009 Conexant Systems Inc.
6  *  Authors  <shu.lin@conexant.com>, <hiep.huynh@conexant.com>
7  *	Based on SAA713x ALSA driver and CX88 driver
8  */
9 
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/device.h>
15 #include <linux/interrupt.h>
16 #include <linux/vmalloc.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/pci.h>
19 #include <linux/slab.h>
20 
21 #include <linux/delay.h>
22 #include <sound/core.h>
23 #include <sound/pcm.h>
24 #include <sound/pcm_params.h>
25 #include <sound/control.h>
26 #include <sound/initval.h>
27 #include <sound/tlv.h>
28 
29 #include "cx25821.h"
30 #include "cx25821-reg.h"
31 
32 #define AUDIO_SRAM_CHANNEL	SRAM_CH08
33 
34 #define dprintk(level, fmt, arg...)				\
35 do {								\
36 	if (debug >= level)					\
37 		pr_info("%s/1: " fmt, chip->dev->name, ##arg);	\
38 } while (0)
39 #define dprintk_core(level, fmt, arg...)				\
40 do {									\
41 	if (debug >= level)						\
42 		printk(KERN_DEBUG "%s/1: " fmt, chip->dev->name, ##arg); \
43 } while (0)
44 
45 /****************************************************************************
46 	Data type declarations - Can be moded to a header file later
47  ****************************************************************************/
48 
49 static int devno;
50 
51 struct cx25821_audio_buffer {
52 	unsigned int bpl;
53 	struct cx25821_riscmem risc;
54 	void			*vaddr;
55 	struct scatterlist	*sglist;
56 	int			sglen;
57 	unsigned long		nr_pages;
58 };
59 
60 struct cx25821_audio_dev {
61 	struct cx25821_dev *dev;
62 	struct cx25821_dmaqueue q;
63 
64 	/* pci i/o */
65 	struct pci_dev *pci;
66 
67 	/* audio controls */
68 	int irq;
69 
70 	struct snd_card *card;
71 
72 	unsigned long iobase;
73 	spinlock_t reg_lock;
74 	atomic_t count;
75 
76 	unsigned int dma_size;
77 	unsigned int period_size;
78 	unsigned int num_periods;
79 
80 	struct cx25821_audio_buffer *buf;
81 
82 	struct snd_pcm_substream *substream;
83 };
84 
85 
86 /****************************************************************************
87 			Module global static vars
88  ****************************************************************************/
89 
90 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
91 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
92 static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;
93 
94 module_param_array(enable, bool, NULL, 0444);
95 MODULE_PARM_DESC(enable, "Enable cx25821 soundcard. default enabled.");
96 
97 module_param_array(index, int, NULL, 0444);
98 MODULE_PARM_DESC(index, "Index value for cx25821 capture interface(s).");
99 
100 /****************************************************************************
101 				Module macros
102  ****************************************************************************/
103 
104 MODULE_DESCRIPTION("ALSA driver module for cx25821 based capture cards");
105 MODULE_AUTHOR("Hiep Huynh");
106 MODULE_LICENSE("GPL");
107 
108 static unsigned int debug;
109 module_param(debug, int, 0644);
110 MODULE_PARM_DESC(debug, "enable debug messages");
111 
112 /****************************************************************************
113 			Module specific functions
114  ****************************************************************************/
115 /* Constants taken from cx88-reg.h */
116 #define AUD_INT_DN_RISCI1       (1 <<  0)
117 #define AUD_INT_UP_RISCI1       (1 <<  1)
118 #define AUD_INT_RDS_DN_RISCI1   (1 <<  2)
119 #define AUD_INT_DN_RISCI2       (1 <<  4)	/* yes, 3 is skipped */
120 #define AUD_INT_UP_RISCI2       (1 <<  5)
121 #define AUD_INT_RDS_DN_RISCI2   (1 <<  6)
122 #define AUD_INT_DN_SYNC         (1 << 12)
123 #define AUD_INT_UP_SYNC         (1 << 13)
124 #define AUD_INT_RDS_DN_SYNC     (1 << 14)
125 #define AUD_INT_OPC_ERR         (1 << 16)
126 #define AUD_INT_BER_IRQ         (1 << 20)
127 #define AUD_INT_MCHG_IRQ        (1 << 21)
128 #define GP_COUNT_CONTROL_RESET	0x3
129 
130 #define PCI_MSK_AUD_EXT   (1 <<  4)
131 #define PCI_MSK_AUD_INT   (1 <<  3)
132 
133 static int cx25821_alsa_dma_init(struct cx25821_audio_dev *chip,
134 				 unsigned long nr_pages)
135 {
136 	struct cx25821_audio_buffer *buf = chip->buf;
137 	struct page *pg;
138 	int i;
139 
140 	buf->vaddr = vmalloc_32(nr_pages << PAGE_SHIFT);
141 	if (NULL == buf->vaddr) {
142 		dprintk(1, "vmalloc_32(%lu pages) failed\n", nr_pages);
143 		return -ENOMEM;
144 	}
145 
146 	dprintk(1, "vmalloc is at addr 0x%p, size=%lu\n",
147 				buf->vaddr,
148 				nr_pages << PAGE_SHIFT);
149 
150 	memset(buf->vaddr, 0, nr_pages << PAGE_SHIFT);
151 	buf->nr_pages = nr_pages;
152 
153 	buf->sglist = vzalloc(array_size(sizeof(*buf->sglist), buf->nr_pages));
154 	if (NULL == buf->sglist)
155 		goto vzalloc_err;
156 
157 	sg_init_table(buf->sglist, buf->nr_pages);
158 	for (i = 0; i < buf->nr_pages; i++) {
159 		pg = vmalloc_to_page(buf->vaddr + i * PAGE_SIZE);
160 		if (NULL == pg)
161 			goto vmalloc_to_page_err;
162 		sg_set_page(&buf->sglist[i], pg, PAGE_SIZE, 0);
163 	}
164 	return 0;
165 
166 vmalloc_to_page_err:
167 	vfree(buf->sglist);
168 	buf->sglist = NULL;
169 vzalloc_err:
170 	vfree(buf->vaddr);
171 	buf->vaddr = NULL;
172 	return -ENOMEM;
173 }
174 
175 static int cx25821_alsa_dma_map(struct cx25821_audio_dev *dev)
176 {
177 	struct cx25821_audio_buffer *buf = dev->buf;
178 
179 	buf->sglen = dma_map_sg(&dev->pci->dev, buf->sglist,
180 			buf->nr_pages, DMA_FROM_DEVICE);
181 
182 	if (0 == buf->sglen) {
183 		pr_warn("%s: cx25821_alsa_map_sg failed\n", __func__);
184 		return -ENOMEM;
185 	}
186 	return 0;
187 }
188 
189 static int cx25821_alsa_dma_unmap(struct cx25821_audio_dev *dev)
190 {
191 	struct cx25821_audio_buffer *buf = dev->buf;
192 
193 	if (!buf->sglen)
194 		return 0;
195 
196 	dma_unmap_sg(&dev->pci->dev, buf->sglist, buf->nr_pages, DMA_FROM_DEVICE);
197 	buf->sglen = 0;
198 	return 0;
199 }
200 
201 static int cx25821_alsa_dma_free(struct cx25821_audio_buffer *buf)
202 {
203 	vfree(buf->sglist);
204 	buf->sglist = NULL;
205 	vfree(buf->vaddr);
206 	buf->vaddr = NULL;
207 	return 0;
208 }
209 
210 /*
211  * BOARD Specific: Sets audio DMA
212  */
213 
214 static int _cx25821_start_audio_dma(struct cx25821_audio_dev *chip)
215 {
216 	struct cx25821_audio_buffer *buf = chip->buf;
217 	struct cx25821_dev *dev = chip->dev;
218 	const struct sram_channel *audio_ch =
219 	    &cx25821_sram_channels[AUDIO_SRAM_CHANNEL];
220 	u32 tmp = 0;
221 
222 	/* enable output on the GPIO 0 for the MCLK ADC (Audio) */
223 	cx25821_set_gpiopin_direction(chip->dev, 0, 0);
224 
225 	/* Make sure RISC/FIFO are off before changing FIFO/RISC settings */
226 	cx_clear(AUD_INT_DMA_CTL,
227 		 FLD_AUD_DST_A_RISC_EN | FLD_AUD_DST_A_FIFO_EN);
228 
229 	/* setup fifo + format - out channel */
230 	cx25821_sram_channel_setup_audio(chip->dev, audio_ch, buf->bpl,
231 					 buf->risc.dma);
232 
233 	/* sets bpl size */
234 	cx_write(AUD_A_LNGTH, buf->bpl);
235 
236 	/* reset counter */
237 	/* GP_COUNT_CONTROL_RESET = 0x3 */
238 	cx_write(AUD_A_GPCNT_CTL, GP_COUNT_CONTROL_RESET);
239 	atomic_set(&chip->count, 0);
240 
241 	/* Set the input mode to 16-bit */
242 	tmp = cx_read(AUD_A_CFG);
243 	cx_write(AUD_A_CFG, tmp | FLD_AUD_DST_PK_MODE | FLD_AUD_DST_ENABLE |
244 		 FLD_AUD_CLK_ENABLE);
245 
246 	/*
247 	pr_info("DEBUG: Start audio DMA, %d B/line, cmds_start(0x%x)= %d lines/FIFO, %d periods, %d byte buffer\n",
248 		buf->bpl, audio_ch->cmds_start,
249 		cx_read(audio_ch->cmds_start + 12)>>1,
250 		chip->num_periods, buf->bpl * chip->num_periods);
251 	*/
252 
253 	/* Enables corresponding bits at AUD_INT_STAT */
254 	cx_write(AUD_A_INT_MSK, FLD_AUD_DST_RISCI1 | FLD_AUD_DST_OF |
255 		 FLD_AUD_DST_SYNC | FLD_AUD_DST_OPC_ERR);
256 
257 	/* Clean any pending interrupt bits already set */
258 	cx_write(AUD_A_INT_STAT, ~0);
259 
260 	/* enable audio irqs */
261 	cx_set(PCI_INT_MSK, chip->dev->pci_irqmask | PCI_MSK_AUD_INT);
262 
263 	/* Turn on audio downstream fifo and risc enable 0x101 */
264 	tmp = cx_read(AUD_INT_DMA_CTL);
265 	cx_set(AUD_INT_DMA_CTL, tmp |
266 	       (FLD_AUD_DST_A_RISC_EN | FLD_AUD_DST_A_FIFO_EN));
267 
268 	mdelay(100);
269 	return 0;
270 }
271 
272 /*
273  * BOARD Specific: Resets audio DMA
274  */
275 static int _cx25821_stop_audio_dma(struct cx25821_audio_dev *chip)
276 {
277 	struct cx25821_dev *dev = chip->dev;
278 
279 	/* stop dma */
280 	cx_clear(AUD_INT_DMA_CTL,
281 		 FLD_AUD_DST_A_RISC_EN | FLD_AUD_DST_A_FIFO_EN);
282 
283 	/* disable irqs */
284 	cx_clear(PCI_INT_MSK, PCI_MSK_AUD_INT);
285 	cx_clear(AUD_A_INT_MSK, AUD_INT_OPC_ERR | AUD_INT_DN_SYNC |
286 		 AUD_INT_DN_RISCI2 | AUD_INT_DN_RISCI1);
287 
288 	return 0;
289 }
290 
291 #define MAX_IRQ_LOOP 50
292 
293 /*
294  * BOARD Specific: IRQ dma bits
295  */
296 static char *cx25821_aud_irqs[32] = {
297 	"dn_risci1", "up_risci1", "rds_dn_risc1",	/* 0-2 */
298 	NULL,						/* reserved */
299 	"dn_risci2", "up_risci2", "rds_dn_risc2",	/* 4-6 */
300 	NULL,						/* reserved */
301 	"dnf_of", "upf_uf", "rds_dnf_uf",		/* 8-10 */
302 	NULL,						/* reserved */
303 	"dn_sync", "up_sync", "rds_dn_sync",		/* 12-14 */
304 	NULL,						/* reserved */
305 	"opc_err", "par_err", "rip_err",		/* 16-18 */
306 	"pci_abort", "ber_irq", "mchg_irq"		/* 19-21 */
307 };
308 
309 /*
310  * BOARD Specific: Threats IRQ audio specific calls
311  */
312 static void cx25821_aud_irq(struct cx25821_audio_dev *chip, u32 status,
313 			    u32 mask)
314 {
315 	struct cx25821_dev *dev = chip->dev;
316 
317 	if (0 == (status & mask))
318 		return;
319 
320 	cx_write(AUD_A_INT_STAT, status);
321 	if (debug > 1 || (status & mask & ~0xff))
322 		cx25821_print_irqbits(dev->name, "irq aud", cx25821_aud_irqs,
323 				ARRAY_SIZE(cx25821_aud_irqs), status, mask);
324 
325 	/* risc op code error */
326 	if (status & AUD_INT_OPC_ERR) {
327 		pr_warn("WARNING %s/1: Audio risc op code error\n", dev->name);
328 
329 		cx_clear(AUD_INT_DMA_CTL,
330 			 FLD_AUD_DST_A_RISC_EN | FLD_AUD_DST_A_FIFO_EN);
331 		cx25821_sram_channel_dump_audio(dev,
332 				&cx25821_sram_channels[AUDIO_SRAM_CHANNEL]);
333 	}
334 	if (status & AUD_INT_DN_SYNC) {
335 		pr_warn("WARNING %s: Downstream sync error!\n", dev->name);
336 		cx_write(AUD_A_GPCNT_CTL, GP_COUNT_CONTROL_RESET);
337 		return;
338 	}
339 
340 	/* risc1 downstream */
341 	if (status & AUD_INT_DN_RISCI1) {
342 		atomic_set(&chip->count, cx_read(AUD_A_GPCNT));
343 		snd_pcm_period_elapsed(chip->substream);
344 	}
345 }
346 
347 /*
348  * BOARD Specific: Handles IRQ calls
349  */
350 static irqreturn_t cx25821_irq(int irq, void *dev_id)
351 {
352 	struct cx25821_audio_dev *chip = dev_id;
353 	struct cx25821_dev *dev = chip->dev;
354 	u32 status, pci_status;
355 	u32 audint_status, audint_mask;
356 	int loop, handled = 0;
357 
358 	audint_status = cx_read(AUD_A_INT_STAT);
359 	audint_mask = cx_read(AUD_A_INT_MSK);
360 	status = cx_read(PCI_INT_STAT);
361 
362 	for (loop = 0; loop < 1; loop++) {
363 		status = cx_read(PCI_INT_STAT);
364 		if (0 == status) {
365 			status = cx_read(PCI_INT_STAT);
366 			audint_status = cx_read(AUD_A_INT_STAT);
367 			audint_mask = cx_read(AUD_A_INT_MSK);
368 
369 			if (status) {
370 				handled = 1;
371 				cx_write(PCI_INT_STAT, status);
372 
373 				cx25821_aud_irq(chip, audint_status,
374 						audint_mask);
375 				break;
376 			} else {
377 				goto out;
378 			}
379 		}
380 
381 		handled = 1;
382 		cx_write(PCI_INT_STAT, status);
383 
384 		cx25821_aud_irq(chip, audint_status, audint_mask);
385 	}
386 
387 	pci_status = cx_read(PCI_INT_STAT);
388 
389 	if (handled)
390 		cx_write(PCI_INT_STAT, pci_status);
391 
392 out:
393 	return IRQ_RETVAL(handled);
394 }
395 
396 static int dsp_buffer_free(struct cx25821_audio_dev *chip)
397 {
398 	struct cx25821_riscmem *risc = &chip->buf->risc;
399 
400 	BUG_ON(!chip->dma_size);
401 
402 	dprintk(2, "Freeing buffer\n");
403 	cx25821_alsa_dma_unmap(chip);
404 	cx25821_alsa_dma_free(chip->buf);
405 	dma_free_coherent(&chip->pci->dev, risc->size, risc->cpu, risc->dma);
406 	kfree(chip->buf);
407 
408 	chip->buf = NULL;
409 	chip->dma_size = 0;
410 
411 	return 0;
412 }
413 
414 /****************************************************************************
415 				ALSA PCM Interface
416  ****************************************************************************/
417 
418 /*
419  * Digital hardware definition
420  */
421 #define DEFAULT_FIFO_SIZE	384
422 static const struct snd_pcm_hardware snd_cx25821_digital_hw = {
423 	.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
424 		SNDRV_PCM_INFO_BLOCK_TRANSFER | SNDRV_PCM_INFO_MMAP_VALID,
425 	.formats = SNDRV_PCM_FMTBIT_S16_LE,
426 
427 	.rates = SNDRV_PCM_RATE_48000,
428 	.rate_min = 48000,
429 	.rate_max = 48000,
430 	.channels_min = 2,
431 	.channels_max = 2,
432 	/* Analog audio output will be full of clicks and pops if there
433 	   are not exactly four lines in the SRAM FIFO buffer.  */
434 	.period_bytes_min = DEFAULT_FIFO_SIZE / 3,
435 	.period_bytes_max = DEFAULT_FIFO_SIZE / 3,
436 	.periods_min = 1,
437 	.periods_max = AUDIO_LINE_SIZE,
438 	/* 128 * 128 = 16384 = 1024 * 16 */
439 	.buffer_bytes_max = (AUDIO_LINE_SIZE * AUDIO_LINE_SIZE),
440 };
441 
442 /*
443  * audio pcm capture open callback
444  */
445 static int snd_cx25821_pcm_open(struct snd_pcm_substream *substream)
446 {
447 	struct cx25821_audio_dev *chip = snd_pcm_substream_chip(substream);
448 	struct snd_pcm_runtime *runtime = substream->runtime;
449 	int err;
450 	unsigned int bpl = 0;
451 
452 	if (!chip) {
453 		pr_err("DEBUG: cx25821 can't find device struct. Can't proceed with open\n");
454 		return -ENODEV;
455 	}
456 
457 	err = snd_pcm_hw_constraint_pow2(runtime, 0,
458 					 SNDRV_PCM_HW_PARAM_PERIODS);
459 	if (err < 0)
460 		goto _error;
461 
462 	chip->substream = substream;
463 
464 	runtime->hw = snd_cx25821_digital_hw;
465 
466 	if (cx25821_sram_channels[AUDIO_SRAM_CHANNEL].fifo_size !=
467 	    DEFAULT_FIFO_SIZE) {
468 		/* since there are 3 audio Clusters */
469 		bpl = cx25821_sram_channels[AUDIO_SRAM_CHANNEL].fifo_size / 3;
470 		bpl &= ~7;	/* must be multiple of 8 */
471 
472 		if (bpl > AUDIO_LINE_SIZE)
473 			bpl = AUDIO_LINE_SIZE;
474 
475 		runtime->hw.period_bytes_min = bpl;
476 		runtime->hw.period_bytes_max = bpl;
477 	}
478 
479 	return 0;
480 _error:
481 	dprintk(1, "Error opening PCM!\n");
482 	return err;
483 }
484 
485 /*
486  * audio close callback
487  */
488 static int snd_cx25821_close(struct snd_pcm_substream *substream)
489 {
490 	return 0;
491 }
492 
493 /*
494  * hw_params callback
495  */
496 static int snd_cx25821_hw_params(struct snd_pcm_substream *substream,
497 				 struct snd_pcm_hw_params *hw_params)
498 {
499 	struct cx25821_audio_dev *chip = snd_pcm_substream_chip(substream);
500 	struct cx25821_audio_buffer *buf;
501 	int ret;
502 
503 	if (substream->runtime->dma_area) {
504 		dsp_buffer_free(chip);
505 		substream->runtime->dma_area = NULL;
506 	}
507 
508 	chip->period_size = params_period_bytes(hw_params);
509 	chip->num_periods = params_periods(hw_params);
510 	chip->dma_size = chip->period_size * params_periods(hw_params);
511 
512 	BUG_ON(!chip->dma_size);
513 	BUG_ON(chip->num_periods & (chip->num_periods - 1));
514 
515 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
516 	if (NULL == buf)
517 		return -ENOMEM;
518 
519 	if (chip->period_size > AUDIO_LINE_SIZE)
520 		chip->period_size = AUDIO_LINE_SIZE;
521 
522 	buf->bpl = chip->period_size;
523 	chip->buf = buf;
524 
525 	ret = cx25821_alsa_dma_init(chip,
526 			(PAGE_ALIGN(chip->dma_size) >> PAGE_SHIFT));
527 	if (ret < 0)
528 		goto error;
529 
530 	ret = cx25821_alsa_dma_map(chip);
531 	if (ret < 0)
532 		goto error;
533 
534 	ret = cx25821_risc_databuffer_audio(chip->pci, &buf->risc, buf->sglist,
535 			chip->period_size, chip->num_periods, 1);
536 	if (ret < 0) {
537 		pr_info("DEBUG: ERROR after cx25821_risc_databuffer_audio()\n");
538 		goto error;
539 	}
540 
541 	/* Loop back to start of program */
542 	buf->risc.jmp[0] = cpu_to_le32(RISC_JUMP | RISC_IRQ1 | RISC_CNT_INC);
543 	buf->risc.jmp[1] = cpu_to_le32(buf->risc.dma);
544 	buf->risc.jmp[2] = cpu_to_le32(0);	/* bits 63-32 */
545 
546 	substream->runtime->dma_area = chip->buf->vaddr;
547 	substream->runtime->dma_bytes = chip->dma_size;
548 	substream->runtime->dma_addr = 0;
549 
550 	return 0;
551 
552 error:
553 	chip->buf = NULL;
554 	kfree(buf);
555 	return ret;
556 }
557 
558 /*
559  * hw free callback
560  */
561 static int snd_cx25821_hw_free(struct snd_pcm_substream *substream)
562 {
563 	struct cx25821_audio_dev *chip = snd_pcm_substream_chip(substream);
564 
565 	if (substream->runtime->dma_area) {
566 		dsp_buffer_free(chip);
567 		substream->runtime->dma_area = NULL;
568 	}
569 
570 	return 0;
571 }
572 
573 /*
574  * prepare callback
575  */
576 static int snd_cx25821_prepare(struct snd_pcm_substream *substream)
577 {
578 	return 0;
579 }
580 
581 /*
582  * trigger callback
583  */
584 static int snd_cx25821_card_trigger(struct snd_pcm_substream *substream,
585 				    int cmd)
586 {
587 	struct cx25821_audio_dev *chip = snd_pcm_substream_chip(substream);
588 	int err = 0;
589 
590 	/* Local interrupts are already disabled by ALSA */
591 	spin_lock(&chip->reg_lock);
592 
593 	switch (cmd) {
594 	case SNDRV_PCM_TRIGGER_START:
595 		err = _cx25821_start_audio_dma(chip);
596 		break;
597 	case SNDRV_PCM_TRIGGER_STOP:
598 		err = _cx25821_stop_audio_dma(chip);
599 		break;
600 	default:
601 		err = -EINVAL;
602 		break;
603 	}
604 
605 	spin_unlock(&chip->reg_lock);
606 
607 	return err;
608 }
609 
610 /*
611  * pointer callback
612  */
613 static snd_pcm_uframes_t snd_cx25821_pointer(struct snd_pcm_substream
614 					     *substream)
615 {
616 	struct cx25821_audio_dev *chip = snd_pcm_substream_chip(substream);
617 	struct snd_pcm_runtime *runtime = substream->runtime;
618 	u16 count;
619 
620 	count = atomic_read(&chip->count);
621 
622 	return runtime->period_size * (count & (runtime->periods - 1));
623 }
624 
625 /*
626  * page callback (needed for mmap)
627  */
628 static struct page *snd_cx25821_page(struct snd_pcm_substream *substream,
629 				     unsigned long offset)
630 {
631 	void *pageptr = substream->runtime->dma_area + offset;
632 
633 	return vmalloc_to_page(pageptr);
634 }
635 
636 /*
637  * operators
638  */
639 static const struct snd_pcm_ops snd_cx25821_pcm_ops = {
640 	.open = snd_cx25821_pcm_open,
641 	.close = snd_cx25821_close,
642 	.hw_params = snd_cx25821_hw_params,
643 	.hw_free = snd_cx25821_hw_free,
644 	.prepare = snd_cx25821_prepare,
645 	.trigger = snd_cx25821_card_trigger,
646 	.pointer = snd_cx25821_pointer,
647 	.page = snd_cx25821_page,
648 };
649 
650 /*
651  * ALSA create a PCM device:  Called when initializing the board.
652  * Sets up the name and hooks up the callbacks
653  */
654 static int snd_cx25821_pcm(struct cx25821_audio_dev *chip, int device,
655 			   char *name)
656 {
657 	struct snd_pcm *pcm;
658 	int err;
659 
660 	err = snd_pcm_new(chip->card, name, device, 0, 1, &pcm);
661 	if (err < 0) {
662 		pr_info("ERROR: FAILED snd_pcm_new() in %s\n", __func__);
663 		return err;
664 	}
665 	pcm->private_data = chip;
666 	pcm->info_flags = 0;
667 	strscpy(pcm->name, name, sizeof(pcm->name));
668 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_cx25821_pcm_ops);
669 
670 	return 0;
671 }
672 
673 /****************************************************************************
674 			Basic Flow for Sound Devices
675  ****************************************************************************/
676 
677 /*
678  * PCI ID Table - 14f1:8801 and 14f1:8811 means function 1: Audio
679  * Only boards with eeprom and byte 1 at eeprom=1 have it
680  */
681 
682 static const struct pci_device_id __maybe_unused cx25821_audio_pci_tbl[] = {
683 	{0x14f1, 0x0920, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
684 	{0,}
685 };
686 
687 MODULE_DEVICE_TABLE(pci, cx25821_audio_pci_tbl);
688 
689 /*
690  * Alsa Constructor - Component probe
691  */
692 static int cx25821_audio_initdev(struct cx25821_dev *dev)
693 {
694 	struct snd_card *card;
695 	struct cx25821_audio_dev *chip;
696 	int err;
697 
698 	if (devno >= SNDRV_CARDS) {
699 		pr_info("DEBUG ERROR: devno >= SNDRV_CARDS %s\n", __func__);
700 		return -ENODEV;
701 	}
702 
703 	if (!enable[devno]) {
704 		++devno;
705 		pr_info("DEBUG ERROR: !enable[devno] %s\n", __func__);
706 		return -ENOENT;
707 	}
708 
709 	err = snd_card_new(&dev->pci->dev, index[devno], id[devno],
710 			   THIS_MODULE,
711 			   sizeof(struct cx25821_audio_dev), &card);
712 	if (err < 0) {
713 		pr_info("DEBUG ERROR: cannot create snd_card_new in %s\n",
714 			__func__);
715 		return err;
716 	}
717 
718 	strscpy(card->driver, "cx25821", sizeof(card->driver));
719 
720 	/* Card "creation" */
721 	chip = card->private_data;
722 	spin_lock_init(&chip->reg_lock);
723 
724 	chip->dev = dev;
725 	chip->card = card;
726 	chip->pci = dev->pci;
727 	chip->iobase = pci_resource_start(dev->pci, 0);
728 
729 	chip->irq = dev->pci->irq;
730 
731 	err = request_irq(dev->pci->irq, cx25821_irq,
732 			  IRQF_SHARED, chip->dev->name, chip);
733 
734 	if (err < 0) {
735 		pr_err("ERROR %s: can't get IRQ %d for ALSA\n", chip->dev->name,
736 			dev->pci->irq);
737 		goto error;
738 	}
739 
740 	err = snd_cx25821_pcm(chip, 0, "cx25821 Digital");
741 	if (err < 0) {
742 		pr_info("DEBUG ERROR: cannot create snd_cx25821_pcm %s\n",
743 			__func__);
744 		goto error;
745 	}
746 
747 	strscpy(card->shortname, "cx25821", sizeof(card->shortname));
748 	sprintf(card->longname, "%s at 0x%lx irq %d", chip->dev->name,
749 		chip->iobase, chip->irq);
750 	strscpy(card->mixername, "CX25821", sizeof(card->mixername));
751 
752 	pr_info("%s/%i: ALSA support for cx25821 boards\n", card->driver,
753 		devno);
754 
755 	err = snd_card_register(card);
756 	if (err < 0) {
757 		pr_info("DEBUG ERROR: cannot register sound card %s\n",
758 			__func__);
759 		goto error;
760 	}
761 
762 	dev->card = card;
763 	devno++;
764 	return 0;
765 
766 error:
767 	snd_card_free(card);
768 	return err;
769 }
770 
771 /****************************************************************************
772 				LINUX MODULE INIT
773  ****************************************************************************/
774 
775 static int cx25821_alsa_exit_callback(struct device *dev, void *data)
776 {
777 	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
778 	struct cx25821_dev *cxdev = get_cx25821(v4l2_dev);
779 
780 	snd_card_free(cxdev->card);
781 	return 0;
782 }
783 
784 static void cx25821_audio_fini(void)
785 {
786 	struct device_driver *drv = driver_find("cx25821", &pci_bus_type);
787 	int ret;
788 
789 	ret = driver_for_each_device(drv, NULL, NULL, cx25821_alsa_exit_callback);
790 	if (ret)
791 		pr_err("%s failed to find a cx25821 driver.\n", __func__);
792 }
793 
794 static int cx25821_alsa_init_callback(struct device *dev, void *data)
795 {
796 	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
797 	struct cx25821_dev *cxdev = get_cx25821(v4l2_dev);
798 
799 	cx25821_audio_initdev(cxdev);
800 	return 0;
801 }
802 
803 /*
804  * Module initializer
805  *
806  * Loops through present saa7134 cards, and assigns an ALSA device
807  * to each one
808  *
809  */
810 static int cx25821_alsa_init(void)
811 {
812 	struct device_driver *drv = driver_find("cx25821", &pci_bus_type);
813 
814 	return driver_for_each_device(drv, NULL, NULL, cx25821_alsa_init_callback);
815 
816 }
817 
818 late_initcall(cx25821_alsa_init);
819 module_exit(cx25821_audio_fini);
820