xref: /openbmc/linux/sound/pci/hda/hda_tegra.c (revision 45ad842eafe484cc32e533823bc71878d1ac4a90)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *
4  * Implementation of primary ALSA driver code base for NVIDIA Tegra HDA.
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/clocksource.h>
9 #include <linux/completion.h>
10 #include <linux/delay.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/mutex.h>
19 #include <linux/of.h>
20 #include <linux/platform_device.h>
21 #include <linux/reset.h>
22 #include <linux/slab.h>
23 #include <linux/time.h>
24 #include <linux/string.h>
25 #include <linux/pm_runtime.h>
26 
27 #include <sound/core.h>
28 #include <sound/initval.h>
29 
30 #include <sound/hda_codec.h>
31 #include "hda_controller.h"
32 
33 /* Defines for Nvidia Tegra HDA support */
34 #define HDA_BAR0           0x8000
35 
36 #define HDA_CFG_CMD        0x1004
37 #define HDA_CFG_BAR0       0x1010
38 
39 #define HDA_ENABLE_IO_SPACE       (1 << 0)
40 #define HDA_ENABLE_MEM_SPACE      (1 << 1)
41 #define HDA_ENABLE_BUS_MASTER     (1 << 2)
42 #define HDA_ENABLE_SERR           (1 << 8)
43 #define HDA_DISABLE_INTR          (1 << 10)
44 #define HDA_BAR0_INIT_PROGRAM     0xFFFFFFFF
45 #define HDA_BAR0_FINAL_PROGRAM    (1 << 14)
46 
47 /* IPFS */
48 #define HDA_IPFS_CONFIG           0x180
49 #define HDA_IPFS_EN_FPCI          0x1
50 
51 #define HDA_IPFS_FPCI_BAR0        0x80
52 #define HDA_FPCI_BAR0_START       0x40
53 
54 #define HDA_IPFS_INTR_MASK        0x188
55 #define HDA_IPFS_EN_INTR          (1 << 16)
56 
57 /* FPCI */
58 #define FPCI_DBG_CFG_2		  0x10F4
59 #define FPCI_GCAP_NSDO_SHIFT	  18
60 #define FPCI_GCAP_NSDO_MASK	  (0x3 << FPCI_GCAP_NSDO_SHIFT)
61 
62 /* max number of SDs */
63 #define NUM_CAPTURE_SD 1
64 #define NUM_PLAYBACK_SD 1
65 
66 /*
67  * Tegra194 does not reflect correct number of SDO lines. Below macro
68  * is used to update the GCAP register to workaround the issue.
69  */
70 #define TEGRA194_NUM_SDO_LINES	  4
71 
72 struct hda_tegra_soc {
73 	bool has_hda2codec_2x_reset;
74 	bool has_hda2hdmi;
75 	bool has_hda2codec_2x;
76 	bool input_stream;
77 	bool always_on;
78 	bool requires_init;
79 };
80 
81 struct hda_tegra {
82 	struct azx chip;
83 	struct device *dev;
84 	struct reset_control_bulk_data resets[3];
85 	struct clk_bulk_data clocks[3];
86 	unsigned int nresets;
87 	unsigned int nclocks;
88 	void __iomem *regs;
89 	struct work_struct probe_work;
90 	const struct hda_tegra_soc *soc;
91 };
92 
93 #ifdef CONFIG_PM
94 static int power_save = CONFIG_SND_HDA_POWER_SAVE_DEFAULT;
95 module_param(power_save, bint, 0644);
96 MODULE_PARM_DESC(power_save,
97 		 "Automatic power-saving timeout (in seconds, 0 = disable).");
98 #else
99 #define power_save	0
100 #endif
101 
102 static const struct hda_controller_ops hda_tegra_ops; /* nothing special */
103 
hda_tegra_init(struct hda_tegra * hda)104 static void hda_tegra_init(struct hda_tegra *hda)
105 {
106 	u32 v;
107 
108 	/* Enable PCI access */
109 	v = readl(hda->regs + HDA_IPFS_CONFIG);
110 	v |= HDA_IPFS_EN_FPCI;
111 	writel(v, hda->regs + HDA_IPFS_CONFIG);
112 
113 	/* Enable MEM/IO space and bus master */
114 	v = readl(hda->regs + HDA_CFG_CMD);
115 	v &= ~HDA_DISABLE_INTR;
116 	v |= HDA_ENABLE_MEM_SPACE | HDA_ENABLE_IO_SPACE |
117 		HDA_ENABLE_BUS_MASTER | HDA_ENABLE_SERR;
118 	writel(v, hda->regs + HDA_CFG_CMD);
119 
120 	writel(HDA_BAR0_INIT_PROGRAM, hda->regs + HDA_CFG_BAR0);
121 	writel(HDA_BAR0_FINAL_PROGRAM, hda->regs + HDA_CFG_BAR0);
122 	writel(HDA_FPCI_BAR0_START, hda->regs + HDA_IPFS_FPCI_BAR0);
123 
124 	v = readl(hda->regs + HDA_IPFS_INTR_MASK);
125 	v |= HDA_IPFS_EN_INTR;
126 	writel(v, hda->regs + HDA_IPFS_INTR_MASK);
127 }
128 
129 /*
130  * power management
131  */
hda_tegra_suspend(struct device * dev)132 static int __maybe_unused hda_tegra_suspend(struct device *dev)
133 {
134 	struct snd_card *card = dev_get_drvdata(dev);
135 	int rc;
136 
137 	rc = pm_runtime_force_suspend(dev);
138 	if (rc < 0)
139 		return rc;
140 	snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
141 
142 	return 0;
143 }
144 
hda_tegra_resume(struct device * dev)145 static int __maybe_unused hda_tegra_resume(struct device *dev)
146 {
147 	struct snd_card *card = dev_get_drvdata(dev);
148 	int rc;
149 
150 	rc = pm_runtime_force_resume(dev);
151 	if (rc < 0)
152 		return rc;
153 	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
154 
155 	return 0;
156 }
157 
hda_tegra_runtime_suspend(struct device * dev)158 static int __maybe_unused hda_tegra_runtime_suspend(struct device *dev)
159 {
160 	struct snd_card *card = dev_get_drvdata(dev);
161 	struct azx *chip = card->private_data;
162 	struct hda_tegra *hda = container_of(chip, struct hda_tegra, chip);
163 
164 	if (chip && chip->running) {
165 		/* enable controller wake up event */
166 		azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
167 			   STATESTS_INT_MASK);
168 
169 		azx_stop_chip(chip);
170 		azx_enter_link_reset(chip);
171 	}
172 	clk_bulk_disable_unprepare(hda->nclocks, hda->clocks);
173 
174 	return 0;
175 }
176 
hda_tegra_runtime_resume(struct device * dev)177 static int __maybe_unused hda_tegra_runtime_resume(struct device *dev)
178 {
179 	struct snd_card *card = dev_get_drvdata(dev);
180 	struct azx *chip = card->private_data;
181 	struct hda_tegra *hda = container_of(chip, struct hda_tegra, chip);
182 	int rc;
183 
184 	if (!chip->running) {
185 		rc = reset_control_bulk_assert(hda->nresets, hda->resets);
186 		if (rc)
187 			return rc;
188 	}
189 
190 	rc = clk_bulk_prepare_enable(hda->nclocks, hda->clocks);
191 	if (rc != 0)
192 		return rc;
193 	if (chip->running) {
194 		if (hda->soc->requires_init)
195 			hda_tegra_init(hda);
196 
197 		azx_init_chip(chip, 1);
198 		/* disable controller wake up event*/
199 		azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) &
200 			   ~STATESTS_INT_MASK);
201 	} else {
202 		usleep_range(10, 100);
203 
204 		rc = reset_control_bulk_deassert(hda->nresets, hda->resets);
205 		if (rc)
206 			return rc;
207 	}
208 
209 	return 0;
210 }
211 
212 static const struct dev_pm_ops hda_tegra_pm = {
213 	SET_SYSTEM_SLEEP_PM_OPS(hda_tegra_suspend, hda_tegra_resume)
214 	SET_RUNTIME_PM_OPS(hda_tegra_runtime_suspend,
215 			   hda_tegra_runtime_resume,
216 			   NULL)
217 };
218 
hda_tegra_dev_disconnect(struct snd_device * device)219 static int hda_tegra_dev_disconnect(struct snd_device *device)
220 {
221 	struct azx *chip = device->device_data;
222 
223 	chip->bus.shutdown = 1;
224 	return 0;
225 }
226 
227 /*
228  * destructor
229  */
hda_tegra_dev_free(struct snd_device * device)230 static int hda_tegra_dev_free(struct snd_device *device)
231 {
232 	struct azx *chip = device->device_data;
233 	struct hda_tegra *hda = container_of(chip, struct hda_tegra, chip);
234 
235 	cancel_work_sync(&hda->probe_work);
236 	if (azx_bus(chip)->chip_init) {
237 		azx_stop_all_streams(chip);
238 		azx_stop_chip(chip);
239 	}
240 
241 	azx_free_stream_pages(chip);
242 	azx_free_streams(chip);
243 	snd_hdac_bus_exit(azx_bus(chip));
244 
245 	return 0;
246 }
247 
hda_tegra_init_chip(struct azx * chip,struct platform_device * pdev)248 static int hda_tegra_init_chip(struct azx *chip, struct platform_device *pdev)
249 {
250 	struct hda_tegra *hda = container_of(chip, struct hda_tegra, chip);
251 	struct hdac_bus *bus = azx_bus(chip);
252 	struct resource *res;
253 
254 	hda->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
255 	if (IS_ERR(hda->regs))
256 		return PTR_ERR(hda->regs);
257 
258 	bus->remap_addr = hda->regs + HDA_BAR0;
259 	bus->addr = res->start + HDA_BAR0;
260 
261 	if (hda->soc->requires_init)
262 		hda_tegra_init(hda);
263 
264 	return 0;
265 }
266 
hda_tegra_first_init(struct azx * chip,struct platform_device * pdev)267 static int hda_tegra_first_init(struct azx *chip, struct platform_device *pdev)
268 {
269 	struct hda_tegra *hda = container_of(chip, struct hda_tegra, chip);
270 	struct hdac_bus *bus = azx_bus(chip);
271 	struct snd_card *card = chip->card;
272 	int err;
273 	unsigned short gcap;
274 	int irq_id = platform_get_irq(pdev, 0);
275 	const char *sname, *drv_name = "tegra-hda";
276 	struct device_node *np = pdev->dev.of_node;
277 
278 	if (irq_id < 0)
279 		return irq_id;
280 
281 	err = hda_tegra_init_chip(chip, pdev);
282 	if (err)
283 		return err;
284 
285 	err = devm_request_irq(chip->card->dev, irq_id, azx_interrupt,
286 			     IRQF_SHARED, KBUILD_MODNAME, chip);
287 	if (err) {
288 		dev_err(chip->card->dev,
289 			"unable to request IRQ %d, disabling device\n",
290 			irq_id);
291 		return err;
292 	}
293 	bus->irq = irq_id;
294 	bus->dma_stop_delay = 100;
295 	card->sync_irq = bus->irq;
296 
297 	/*
298 	 * Tegra194 has 4 SDO lines and the STRIPE can be used to
299 	 * indicate how many of the SDO lines the stream should be
300 	 * striped. But GCAP register does not reflect the true
301 	 * capability of HW. Below workaround helps to fix this.
302 	 *
303 	 * GCAP_NSDO is bits 19:18 in T_AZA_DBG_CFG_2,
304 	 * 0 for 1 SDO, 1 for 2 SDO, 2 for 4 SDO lines.
305 	 */
306 	if (of_device_is_compatible(np, "nvidia,tegra194-hda")) {
307 		u32 val;
308 
309 		dev_info(card->dev, "Override SDO lines to %u\n",
310 			 TEGRA194_NUM_SDO_LINES);
311 
312 		val = readl(hda->regs + FPCI_DBG_CFG_2) & ~FPCI_GCAP_NSDO_MASK;
313 		val |= (TEGRA194_NUM_SDO_LINES >> 1) << FPCI_GCAP_NSDO_SHIFT;
314 		writel(val, hda->regs + FPCI_DBG_CFG_2);
315 	}
316 
317 	gcap = azx_readw(chip, GCAP);
318 	dev_dbg(card->dev, "chipset global capabilities = 0x%x\n", gcap);
319 
320 	chip->align_buffer_size = 1;
321 
322 	/* read number of streams from GCAP register instead of using
323 	 * hardcoded value
324 	 */
325 	chip->capture_streams = (gcap >> 8) & 0x0f;
326 
327 	/* The GCAP register on Tegra234 implies no Input Streams(ISS) support,
328 	 * but the HW output stream descriptor programming should start with
329 	 * offset 0x20*4 from base stream descriptor address. This will be a
330 	 * problem while calculating the offset for output stream descriptor
331 	 * which will be considering input stream also. So here output stream
332 	 * starts with offset 0 which is wrong as HW register for output stream
333 	 * offset starts with 4.
334 	 */
335 	if (!hda->soc->input_stream)
336 		chip->capture_streams = 4;
337 
338 	chip->playback_streams = (gcap >> 12) & 0x0f;
339 	if (!chip->playback_streams && !chip->capture_streams) {
340 		/* gcap didn't give any info, switching to old method */
341 		chip->playback_streams = NUM_PLAYBACK_SD;
342 		chip->capture_streams = NUM_CAPTURE_SD;
343 	}
344 	chip->capture_index_offset = 0;
345 	chip->playback_index_offset = chip->capture_streams;
346 	chip->num_streams = chip->playback_streams + chip->capture_streams;
347 
348 	/* initialize streams */
349 	err = azx_init_streams(chip);
350 	if (err < 0) {
351 		dev_err(card->dev, "failed to initialize streams: %d\n", err);
352 		return err;
353 	}
354 
355 	err = azx_alloc_stream_pages(chip);
356 	if (err < 0) {
357 		dev_err(card->dev, "failed to allocate stream pages: %d\n",
358 			err);
359 		return err;
360 	}
361 
362 	/* initialize chip */
363 	azx_init_chip(chip, 1);
364 
365 	/*
366 	 * Playback (for 44.1K/48K, 2-channel, 16-bps) fails with
367 	 * 4 SDO lines due to legacy design limitation. Following
368 	 * is, from HD Audio Specification (Revision 1.0a), used to
369 	 * control striping of the stream across multiple SDO lines
370 	 * for sample rates <= 48K.
371 	 *
372 	 * { ((num_channels * bits_per_sample) / number of SDOs) >= 8 }
373 	 *
374 	 * Due to legacy design issue it is recommended that above
375 	 * ratio must be greater than 8. Since number of SDO lines is
376 	 * in powers of 2, next available ratio is 16 which can be
377 	 * used as a limiting factor here.
378 	 */
379 	if (of_device_is_compatible(np, "nvidia,tegra30-hda"))
380 		chip->bus.core.sdo_limit = 16;
381 
382 	/* codec detection */
383 	if (!bus->codec_mask) {
384 		dev_err(card->dev, "no codecs found!\n");
385 		return -ENODEV;
386 	}
387 
388 	/* driver name */
389 	strscpy(card->driver, drv_name, sizeof(card->driver));
390 	/* shortname for card */
391 	sname = of_get_property(np, "nvidia,model", NULL);
392 	if (!sname)
393 		sname = drv_name;
394 	if (strlen(sname) > sizeof(card->shortname))
395 		dev_info(card->dev, "truncating shortname for card\n");
396 	strscpy(card->shortname, sname, sizeof(card->shortname));
397 
398 	/* longname for card */
399 	snprintf(card->longname, sizeof(card->longname),
400 		 "%s at 0x%lx irq %i",
401 		 card->shortname, bus->addr, bus->irq);
402 
403 	return 0;
404 }
405 
406 /*
407  * constructor
408  */
409 
410 static void hda_tegra_probe_work(struct work_struct *work);
411 
hda_tegra_create(struct snd_card * card,unsigned int driver_caps,struct hda_tegra * hda)412 static int hda_tegra_create(struct snd_card *card,
413 			    unsigned int driver_caps,
414 			    struct hda_tegra *hda)
415 {
416 	static const struct snd_device_ops ops = {
417 		.dev_disconnect = hda_tegra_dev_disconnect,
418 		.dev_free = hda_tegra_dev_free,
419 	};
420 	struct azx *chip;
421 	int err;
422 
423 	chip = &hda->chip;
424 
425 	mutex_init(&chip->open_mutex);
426 	chip->card = card;
427 	chip->ops = &hda_tegra_ops;
428 	chip->driver_caps = driver_caps;
429 	chip->driver_type = driver_caps & 0xff;
430 	chip->dev_index = 0;
431 	INIT_LIST_HEAD(&chip->pcm_list);
432 
433 	chip->codec_probe_mask = -1;
434 
435 	chip->single_cmd = false;
436 	chip->snoop = true;
437 
438 	INIT_WORK(&hda->probe_work, hda_tegra_probe_work);
439 
440 	err = azx_bus_init(chip, NULL);
441 	if (err < 0)
442 		return err;
443 
444 	chip->bus.core.sync_write = 0;
445 	chip->bus.core.needs_damn_long_delay = 1;
446 	chip->bus.core.aligned_mmio = 1;
447 
448 	/*
449 	 * HDA power domain and clocks are always on for Tegra264 and
450 	 * the jack detection logic would work always, so no need of
451 	 * jack polling mechanism running.
452 	 */
453 	if (!hda->soc->always_on) {
454 		chip->jackpoll_interval = msecs_to_jiffies(5000);
455 		chip->bus.jackpoll_in_suspend = 1;
456 	}
457 
458 	err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
459 	if (err < 0) {
460 		dev_err(card->dev, "Error creating device\n");
461 		return err;
462 	}
463 
464 	return 0;
465 }
466 
467 static const struct hda_tegra_soc tegra30_data = {
468 	.has_hda2codec_2x_reset = true,
469 	.has_hda2hdmi = true,
470 	.has_hda2codec_2x = true,
471 	.input_stream = true,
472 	.always_on = false,
473 	.requires_init = true,
474 };
475 
476 static const struct hda_tegra_soc tegra194_data = {
477 	.has_hda2codec_2x_reset = false,
478 	.has_hda2hdmi = true,
479 	.has_hda2codec_2x = true,
480 	.input_stream = true,
481 	.always_on = false,
482 	.requires_init = true,
483 };
484 
485 static const struct hda_tegra_soc tegra234_data = {
486 	.has_hda2codec_2x_reset = true,
487 	.has_hda2hdmi = false,
488 	.has_hda2codec_2x = true,
489 	.input_stream = false,
490 	.always_on = false,
491 	.requires_init = true,
492 };
493 
494 static const struct hda_tegra_soc tegra264_data = {
495 	.has_hda2codec_2x_reset = true,
496 	.has_hda2hdmi = false,
497 	.has_hda2codec_2x = false,
498 	.input_stream = false,
499 	.always_on = true,
500 	.requires_init = false,
501 };
502 
503 static const struct of_device_id hda_tegra_match[] = {
504 	{ .compatible = "nvidia,tegra30-hda", .data = &tegra30_data },
505 	{ .compatible = "nvidia,tegra194-hda", .data = &tegra194_data },
506 	{ .compatible = "nvidia,tegra234-hda", .data = &tegra234_data },
507 	{ .compatible = "nvidia,tegra264-hda", .data = &tegra264_data },
508 	{},
509 };
510 MODULE_DEVICE_TABLE(of, hda_tegra_match);
511 
hda_tegra_probe(struct platform_device * pdev)512 static int hda_tegra_probe(struct platform_device *pdev)
513 {
514 	const unsigned int driver_flags = AZX_DCAPS_CORBRP_SELF_CLEAR |
515 					  AZX_DCAPS_PM_RUNTIME |
516 					  AZX_DCAPS_4K_BDLE_BOUNDARY;
517 	struct snd_card *card;
518 	struct azx *chip;
519 	struct hda_tegra *hda;
520 	int err;
521 
522 	hda = devm_kzalloc(&pdev->dev, sizeof(*hda), GFP_KERNEL);
523 	if (!hda)
524 		return -ENOMEM;
525 	hda->dev = &pdev->dev;
526 	chip = &hda->chip;
527 
528 	hda->soc = of_device_get_match_data(&pdev->dev);
529 
530 	err = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
531 			   THIS_MODULE, 0, &card);
532 	if (err < 0) {
533 		dev_err(&pdev->dev, "Error creating card!\n");
534 		return err;
535 	}
536 
537 	hda->resets[hda->nresets++].id = "hda";
538 
539 	/*
540 	 * "hda2hdmi" is not applicable for Tegra234. This is because the
541 	 * codec is separate IP and not under display SOR partition now.
542 	 */
543 	if (hda->soc->has_hda2hdmi)
544 		hda->resets[hda->nresets++].id = "hda2hdmi";
545 
546 	/*
547 	 * "hda2codec_2x" reset is not present on Tegra194. Though DT would
548 	 * be updated to reflect this, but to have backward compatibility
549 	 * below is necessary.
550 	 */
551 	if (hda->soc->has_hda2codec_2x_reset)
552 		hda->resets[hda->nresets++].id = "hda2codec_2x";
553 
554 	err = devm_reset_control_bulk_get_exclusive(&pdev->dev, hda->nresets,
555 						    hda->resets);
556 	if (err)
557 		goto out_free;
558 
559 	hda->clocks[hda->nclocks++].id = "hda";
560 	if (hda->soc->has_hda2hdmi)
561 		hda->clocks[hda->nclocks++].id = "hda2hdmi";
562 
563 	if (hda->soc->has_hda2codec_2x)
564 		hda->clocks[hda->nclocks++].id = "hda2codec_2x";
565 
566 	err = devm_clk_bulk_get(&pdev->dev, hda->nclocks, hda->clocks);
567 	if (err < 0)
568 		goto out_free;
569 
570 	err = hda_tegra_create(card, driver_flags, hda);
571 	if (err < 0)
572 		goto out_free;
573 	card->private_data = chip;
574 
575 	dev_set_drvdata(&pdev->dev, card);
576 
577 	pm_runtime_enable(hda->dev);
578 	if (!azx_has_pm_runtime(chip))
579 		pm_runtime_forbid(hda->dev);
580 
581 	schedule_work(&hda->probe_work);
582 
583 	return 0;
584 
585 out_free:
586 	snd_card_free(card);
587 	return err;
588 }
589 
hda_tegra_probe_work(struct work_struct * work)590 static void hda_tegra_probe_work(struct work_struct *work)
591 {
592 	struct hda_tegra *hda = container_of(work, struct hda_tegra, probe_work);
593 	struct azx *chip = &hda->chip;
594 	struct platform_device *pdev = to_platform_device(hda->dev);
595 	int err;
596 
597 	pm_runtime_get_sync(hda->dev);
598 	err = hda_tegra_first_init(chip, pdev);
599 	if (err < 0)
600 		goto out_free;
601 
602 	/* create codec instances */
603 	err = azx_probe_codecs(chip, 8);
604 	if (err < 0)
605 		goto out_free;
606 
607 	err = azx_codec_configure(chip);
608 	if (err < 0)
609 		goto out_free;
610 
611 	err = snd_card_register(chip->card);
612 	if (err < 0)
613 		goto out_free;
614 
615 	chip->running = 1;
616 	snd_hda_set_power_save(&chip->bus, power_save * 1000);
617 
618  out_free:
619 	pm_runtime_put(hda->dev);
620 	return; /* no error return from async probe */
621 }
622 
hda_tegra_remove(struct platform_device * pdev)623 static void hda_tegra_remove(struct platform_device *pdev)
624 {
625 	snd_card_free(dev_get_drvdata(&pdev->dev));
626 	pm_runtime_disable(&pdev->dev);
627 }
628 
hda_tegra_shutdown(struct platform_device * pdev)629 static void hda_tegra_shutdown(struct platform_device *pdev)
630 {
631 	struct snd_card *card = dev_get_drvdata(&pdev->dev);
632 	struct azx *chip;
633 
634 	if (!card)
635 		return;
636 	chip = card->private_data;
637 	if (chip && chip->running)
638 		azx_stop_chip(chip);
639 }
640 
641 static struct platform_driver tegra_platform_hda = {
642 	.driver = {
643 		.name = "tegra-hda",
644 		.pm = &hda_tegra_pm,
645 		.of_match_table = hda_tegra_match,
646 	},
647 	.probe = hda_tegra_probe,
648 	.remove_new = hda_tegra_remove,
649 	.shutdown = hda_tegra_shutdown,
650 };
651 module_platform_driver(tegra_platform_hda);
652 
653 MODULE_DESCRIPTION("Tegra HDA bus driver");
654 MODULE_LICENSE("GPL v2");
655