xref: /openbmc/linux/sound/soc/tegra/tegra20_ac97.c (revision 3ddc8b84)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * tegra20_ac97.c - Tegra20 AC97 platform driver
4  *
5  * Copyright (c) 2012 Lucas Stach <dev@lynxeye.de>
6  *
7  * Partly based on code copyright/by:
8  *
9  * Copyright (c) 2011,2012 Toradex Inc.
10  */
11 
12 #include <linux/clk.h>
13 #include <linux/delay.h>
14 #include <linux/device.h>
15 #include <linux/gpio.h>
16 #include <linux/io.h>
17 #include <linux/jiffies.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/of_gpio.h>
21 #include <linux/platform_device.h>
22 #include <linux/regmap.h>
23 #include <linux/reset.h>
24 #include <linux/slab.h>
25 #include <sound/core.h>
26 #include <sound/pcm.h>
27 #include <sound/pcm_params.h>
28 #include <sound/soc.h>
29 #include <sound/dmaengine_pcm.h>
30 
31 #include "tegra20_ac97.h"
32 
33 #define DRV_NAME "tegra20-ac97"
34 
35 static struct tegra20_ac97 *workdata;
36 
37 static void tegra20_ac97_codec_reset(struct snd_ac97 *ac97)
38 {
39 	u32 readback;
40 	unsigned long timeout;
41 
42 	/* reset line is not driven by DAC pad group, have to toggle GPIO */
43 	gpio_set_value(workdata->reset_gpio, 0);
44 	udelay(2);
45 
46 	gpio_set_value(workdata->reset_gpio, 1);
47 	udelay(2);
48 
49 	timeout = jiffies + msecs_to_jiffies(100);
50 
51 	do {
52 		regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
53 		if (readback & TEGRA20_AC97_STATUS1_CODEC1_RDY)
54 			break;
55 		usleep_range(1000, 2000);
56 	} while (!time_after(jiffies, timeout));
57 }
58 
59 static void tegra20_ac97_codec_warm_reset(struct snd_ac97 *ac97)
60 {
61 	u32 readback;
62 	unsigned long timeout;
63 
64 	/*
65 	 * although sync line is driven by the DAC pad group warm reset using
66 	 * the controller cmd is not working, have to toggle sync line
67 	 * manually.
68 	 */
69 	gpio_request(workdata->sync_gpio, "codec-sync");
70 
71 	gpio_direction_output(workdata->sync_gpio, 1);
72 
73 	udelay(2);
74 	gpio_set_value(workdata->sync_gpio, 0);
75 	udelay(2);
76 	gpio_free(workdata->sync_gpio);
77 
78 	timeout = jiffies + msecs_to_jiffies(100);
79 
80 	do {
81 		regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
82 		if (readback & TEGRA20_AC97_STATUS1_CODEC1_RDY)
83 			break;
84 		usleep_range(1000, 2000);
85 	} while (!time_after(jiffies, timeout));
86 }
87 
88 static unsigned short tegra20_ac97_codec_read(struct snd_ac97 *ac97_snd,
89 					      unsigned short reg)
90 {
91 	u32 readback;
92 	unsigned long timeout;
93 
94 	regmap_write(workdata->regmap, TEGRA20_AC97_CMD,
95 		     (((reg | 0x80) << TEGRA20_AC97_CMD_CMD_ADDR_SHIFT) &
96 		      TEGRA20_AC97_CMD_CMD_ADDR_MASK) |
97 		     TEGRA20_AC97_CMD_BUSY);
98 
99 	timeout = jiffies + msecs_to_jiffies(100);
100 
101 	do {
102 		regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
103 		if (readback & TEGRA20_AC97_STATUS1_STA_VALID1)
104 			break;
105 		usleep_range(1000, 2000);
106 	} while (!time_after(jiffies, timeout));
107 
108 	return ((readback & TEGRA20_AC97_STATUS1_STA_DATA1_MASK) >>
109 		TEGRA20_AC97_STATUS1_STA_DATA1_SHIFT);
110 }
111 
112 static void tegra20_ac97_codec_write(struct snd_ac97 *ac97_snd,
113 				     unsigned short reg, unsigned short val)
114 {
115 	u32 readback;
116 	unsigned long timeout;
117 
118 	regmap_write(workdata->regmap, TEGRA20_AC97_CMD,
119 		     ((reg << TEGRA20_AC97_CMD_CMD_ADDR_SHIFT) &
120 		      TEGRA20_AC97_CMD_CMD_ADDR_MASK) |
121 		     ((val << TEGRA20_AC97_CMD_CMD_DATA_SHIFT) &
122 		      TEGRA20_AC97_CMD_CMD_DATA_MASK) |
123 		     TEGRA20_AC97_CMD_BUSY);
124 
125 	timeout = jiffies + msecs_to_jiffies(100);
126 
127 	do {
128 		regmap_read(workdata->regmap, TEGRA20_AC97_CMD, &readback);
129 		if (!(readback & TEGRA20_AC97_CMD_BUSY))
130 			break;
131 		usleep_range(1000, 2000);
132 	} while (!time_after(jiffies, timeout));
133 }
134 
135 static struct snd_ac97_bus_ops tegra20_ac97_ops = {
136 	.read		= tegra20_ac97_codec_read,
137 	.write		= tegra20_ac97_codec_write,
138 	.reset		= tegra20_ac97_codec_reset,
139 	.warm_reset	= tegra20_ac97_codec_warm_reset,
140 };
141 
142 static inline void tegra20_ac97_start_playback(struct tegra20_ac97 *ac97)
143 {
144 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
145 			   TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN,
146 			   TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN);
147 
148 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_CTRL,
149 			   TEGRA20_AC97_CTRL_PCM_DAC_EN |
150 			   TEGRA20_AC97_CTRL_STM_EN,
151 			   TEGRA20_AC97_CTRL_PCM_DAC_EN |
152 			   TEGRA20_AC97_CTRL_STM_EN);
153 }
154 
155 static inline void tegra20_ac97_stop_playback(struct tegra20_ac97 *ac97)
156 {
157 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
158 			   TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN, 0);
159 
160 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_CTRL,
161 			   TEGRA20_AC97_CTRL_PCM_DAC_EN, 0);
162 }
163 
164 static inline void tegra20_ac97_start_capture(struct tegra20_ac97 *ac97)
165 {
166 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
167 			   TEGRA20_AC97_FIFO_SCR_REC_FULL_EN,
168 			   TEGRA20_AC97_FIFO_SCR_REC_FULL_EN);
169 }
170 
171 static inline void tegra20_ac97_stop_capture(struct tegra20_ac97 *ac97)
172 {
173 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
174 			   TEGRA20_AC97_FIFO_SCR_REC_FULL_EN, 0);
175 }
176 
177 static int tegra20_ac97_trigger(struct snd_pcm_substream *substream, int cmd,
178 				struct snd_soc_dai *dai)
179 {
180 	struct tegra20_ac97 *ac97 = snd_soc_dai_get_drvdata(dai);
181 
182 	switch (cmd) {
183 	case SNDRV_PCM_TRIGGER_START:
184 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
185 	case SNDRV_PCM_TRIGGER_RESUME:
186 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
187 			tegra20_ac97_start_playback(ac97);
188 		else
189 			tegra20_ac97_start_capture(ac97);
190 		break;
191 	case SNDRV_PCM_TRIGGER_STOP:
192 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
193 	case SNDRV_PCM_TRIGGER_SUSPEND:
194 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
195 			tegra20_ac97_stop_playback(ac97);
196 		else
197 			tegra20_ac97_stop_capture(ac97);
198 		break;
199 	default:
200 		return -EINVAL;
201 	}
202 
203 	return 0;
204 }
205 
206 static int tegra20_ac97_probe(struct snd_soc_dai *dai)
207 {
208 	struct tegra20_ac97 *ac97 = snd_soc_dai_get_drvdata(dai);
209 
210 	snd_soc_dai_init_dma_data(dai,	&ac97->playback_dma_data,
211 					&ac97->capture_dma_data);
212 
213 	return 0;
214 }
215 
216 static const struct snd_soc_dai_ops tegra20_ac97_dai_ops = {
217 	.probe		= tegra20_ac97_probe,
218 	.trigger	= tegra20_ac97_trigger,
219 };
220 
221 static struct snd_soc_dai_driver tegra20_ac97_dai = {
222 	.name = "tegra-ac97-pcm",
223 	.playback = {
224 		.stream_name = "PCM Playback",
225 		.channels_min = 2,
226 		.channels_max = 2,
227 		.rates = SNDRV_PCM_RATE_8000_48000,
228 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
229 	},
230 	.capture = {
231 		.stream_name = "PCM Capture",
232 		.channels_min = 2,
233 		.channels_max = 2,
234 		.rates = SNDRV_PCM_RATE_8000_48000,
235 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
236 	},
237 	.ops = &tegra20_ac97_dai_ops,
238 };
239 
240 static const struct snd_soc_component_driver tegra20_ac97_component = {
241 	.name			= DRV_NAME,
242 	.legacy_dai_naming	= 1,
243 };
244 
245 static bool tegra20_ac97_wr_rd_reg(struct device *dev, unsigned int reg)
246 {
247 	switch (reg) {
248 	case TEGRA20_AC97_CTRL:
249 	case TEGRA20_AC97_CMD:
250 	case TEGRA20_AC97_STATUS1:
251 	case TEGRA20_AC97_FIFO1_SCR:
252 	case TEGRA20_AC97_FIFO_TX1:
253 	case TEGRA20_AC97_FIFO_RX1:
254 		return true;
255 	default:
256 		break;
257 	}
258 
259 	return false;
260 }
261 
262 static bool tegra20_ac97_volatile_reg(struct device *dev, unsigned int reg)
263 {
264 	switch (reg) {
265 	case TEGRA20_AC97_STATUS1:
266 	case TEGRA20_AC97_FIFO1_SCR:
267 	case TEGRA20_AC97_FIFO_TX1:
268 	case TEGRA20_AC97_FIFO_RX1:
269 		return true;
270 	default:
271 		break;
272 	}
273 
274 	return false;
275 }
276 
277 static bool tegra20_ac97_precious_reg(struct device *dev, unsigned int reg)
278 {
279 	switch (reg) {
280 	case TEGRA20_AC97_FIFO_TX1:
281 	case TEGRA20_AC97_FIFO_RX1:
282 		return true;
283 	default:
284 		break;
285 	}
286 
287 	return false;
288 }
289 
290 static const struct regmap_config tegra20_ac97_regmap_config = {
291 	.reg_bits = 32,
292 	.reg_stride = 4,
293 	.val_bits = 32,
294 	.max_register = TEGRA20_AC97_FIFO_RX1,
295 	.writeable_reg = tegra20_ac97_wr_rd_reg,
296 	.readable_reg = tegra20_ac97_wr_rd_reg,
297 	.volatile_reg = tegra20_ac97_volatile_reg,
298 	.precious_reg = tegra20_ac97_precious_reg,
299 	.cache_type = REGCACHE_FLAT,
300 };
301 
302 static int tegra20_ac97_platform_probe(struct platform_device *pdev)
303 {
304 	struct tegra20_ac97 *ac97;
305 	struct resource *mem;
306 	void __iomem *regs;
307 	int ret = 0;
308 
309 	ac97 = devm_kzalloc(&pdev->dev, sizeof(struct tegra20_ac97),
310 			    GFP_KERNEL);
311 	if (!ac97) {
312 		ret = -ENOMEM;
313 		goto err;
314 	}
315 	dev_set_drvdata(&pdev->dev, ac97);
316 
317 	ac97->reset = devm_reset_control_get_exclusive(&pdev->dev, "ac97");
318 	if (IS_ERR(ac97->reset)) {
319 		dev_err(&pdev->dev, "Can't retrieve ac97 reset\n");
320 		ret = PTR_ERR(ac97->reset);
321 		goto err;
322 	}
323 
324 	ac97->clk_ac97 = devm_clk_get(&pdev->dev, NULL);
325 	if (IS_ERR(ac97->clk_ac97)) {
326 		dev_err(&pdev->dev, "Can't retrieve ac97 clock\n");
327 		ret = PTR_ERR(ac97->clk_ac97);
328 		goto err;
329 	}
330 
331 	regs = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
332 	if (IS_ERR(regs)) {
333 		ret = PTR_ERR(regs);
334 		goto err_clk_put;
335 	}
336 
337 	ac97->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
338 					    &tegra20_ac97_regmap_config);
339 	if (IS_ERR(ac97->regmap)) {
340 		dev_err(&pdev->dev, "regmap init failed\n");
341 		ret = PTR_ERR(ac97->regmap);
342 		goto err_clk_put;
343 	}
344 
345 	ac97->reset_gpio = of_get_named_gpio(pdev->dev.of_node,
346 					     "nvidia,codec-reset-gpio", 0);
347 	if (gpio_is_valid(ac97->reset_gpio)) {
348 		ret = devm_gpio_request_one(&pdev->dev, ac97->reset_gpio,
349 					    GPIOF_OUT_INIT_HIGH, "codec-reset");
350 		if (ret) {
351 			dev_err(&pdev->dev, "could not get codec-reset GPIO\n");
352 			goto err_clk_put;
353 		}
354 	} else {
355 		dev_err(&pdev->dev, "no codec-reset GPIO supplied\n");
356 		ret = -EINVAL;
357 		goto err_clk_put;
358 	}
359 
360 	ac97->sync_gpio = of_get_named_gpio(pdev->dev.of_node,
361 					    "nvidia,codec-sync-gpio", 0);
362 	if (!gpio_is_valid(ac97->sync_gpio)) {
363 		dev_err(&pdev->dev, "no codec-sync GPIO supplied\n");
364 		ret = -EINVAL;
365 		goto err_clk_put;
366 	}
367 
368 	ac97->capture_dma_data.addr = mem->start + TEGRA20_AC97_FIFO_RX1;
369 	ac97->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
370 	ac97->capture_dma_data.maxburst = 4;
371 
372 	ac97->playback_dma_data.addr = mem->start + TEGRA20_AC97_FIFO_TX1;
373 	ac97->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
374 	ac97->playback_dma_data.maxburst = 4;
375 
376 	ret = reset_control_assert(ac97->reset);
377 	if (ret) {
378 		dev_err(&pdev->dev, "Failed to assert AC'97 reset: %d\n", ret);
379 		goto err_clk_put;
380 	}
381 
382 	ret = clk_prepare_enable(ac97->clk_ac97);
383 	if (ret) {
384 		dev_err(&pdev->dev, "clk_enable failed: %d\n", ret);
385 		goto err_clk_put;
386 	}
387 
388 	usleep_range(10, 100);
389 
390 	ret = reset_control_deassert(ac97->reset);
391 	if (ret) {
392 		dev_err(&pdev->dev, "Failed to deassert AC'97 reset: %d\n", ret);
393 		goto err_clk_disable_unprepare;
394 	}
395 
396 	ret = snd_soc_set_ac97_ops(&tegra20_ac97_ops);
397 	if (ret) {
398 		dev_err(&pdev->dev, "Failed to set AC'97 ops: %d\n", ret);
399 		goto err_clk_disable_unprepare;
400 	}
401 
402 	ret = snd_soc_register_component(&pdev->dev, &tegra20_ac97_component,
403 					 &tegra20_ac97_dai, 1);
404 	if (ret) {
405 		dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
406 		ret = -ENOMEM;
407 		goto err_clk_disable_unprepare;
408 	}
409 
410 	ret = tegra_pcm_platform_register(&pdev->dev);
411 	if (ret) {
412 		dev_err(&pdev->dev, "Could not register PCM: %d\n", ret);
413 		goto err_unregister_component;
414 	}
415 
416 	/* XXX: crufty ASoC AC97 API - only one AC97 codec allowed */
417 	workdata = ac97;
418 
419 	return 0;
420 
421 err_unregister_component:
422 	snd_soc_unregister_component(&pdev->dev);
423 err_clk_disable_unprepare:
424 	clk_disable_unprepare(ac97->clk_ac97);
425 err_clk_put:
426 err:
427 	snd_soc_set_ac97_ops(NULL);
428 	return ret;
429 }
430 
431 static void tegra20_ac97_platform_remove(struct platform_device *pdev)
432 {
433 	struct tegra20_ac97 *ac97 = dev_get_drvdata(&pdev->dev);
434 
435 	tegra_pcm_platform_unregister(&pdev->dev);
436 	snd_soc_unregister_component(&pdev->dev);
437 
438 	clk_disable_unprepare(ac97->clk_ac97);
439 
440 	snd_soc_set_ac97_ops(NULL);
441 }
442 
443 static const struct of_device_id tegra20_ac97_of_match[] = {
444 	{ .compatible = "nvidia,tegra20-ac97", },
445 	{},
446 };
447 
448 static struct platform_driver tegra20_ac97_driver = {
449 	.driver = {
450 		.name = DRV_NAME,
451 		.of_match_table = tegra20_ac97_of_match,
452 	},
453 	.probe = tegra20_ac97_platform_probe,
454 	.remove_new = tegra20_ac97_platform_remove,
455 };
456 module_platform_driver(tegra20_ac97_driver);
457 
458 MODULE_AUTHOR("Lucas Stach");
459 MODULE_DESCRIPTION("Tegra20 AC97 ASoC driver");
460 MODULE_LICENSE("GPL v2");
461 MODULE_ALIAS("platform:" DRV_NAME);
462 MODULE_DEVICE_TABLE(of, tegra20_ac97_of_match);
463