xref: /openbmc/linux/sound/soc/tegra/tegra20_ac97.c (revision 75020f2d)
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/pm_runtime.h>
23 #include <linux/regmap.h>
24 #include <linux/reset.h>
25 #include <linux/slab.h>
26 #include <sound/core.h>
27 #include <sound/pcm.h>
28 #include <sound/pcm_params.h>
29 #include <sound/soc.h>
30 #include <sound/dmaengine_pcm.h>
31 
32 #include "tegra20_ac97.h"
33 
34 #define DRV_NAME "tegra20-ac97"
35 
36 static struct tegra20_ac97 *workdata;
37 
38 static void tegra20_ac97_codec_reset(struct snd_ac97 *ac97)
39 {
40 	u32 readback;
41 	unsigned long timeout;
42 
43 	/* reset line is not driven by DAC pad group, have to toggle GPIO */
44 	gpio_set_value(workdata->reset_gpio, 0);
45 	udelay(2);
46 
47 	gpio_set_value(workdata->reset_gpio, 1);
48 	udelay(2);
49 
50 	timeout = jiffies + msecs_to_jiffies(100);
51 
52 	do {
53 		regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
54 		if (readback & TEGRA20_AC97_STATUS1_CODEC1_RDY)
55 			break;
56 		usleep_range(1000, 2000);
57 	} while (!time_after(jiffies, timeout));
58 }
59 
60 static void tegra20_ac97_codec_warm_reset(struct snd_ac97 *ac97)
61 {
62 	u32 readback;
63 	unsigned long timeout;
64 
65 	/*
66 	 * although sync line is driven by the DAC pad group warm reset using
67 	 * the controller cmd is not working, have to toggle sync line
68 	 * manually.
69 	 */
70 	gpio_request(workdata->sync_gpio, "codec-sync");
71 
72 	gpio_direction_output(workdata->sync_gpio, 1);
73 
74 	udelay(2);
75 	gpio_set_value(workdata->sync_gpio, 0);
76 	udelay(2);
77 	gpio_free(workdata->sync_gpio);
78 
79 	timeout = jiffies + msecs_to_jiffies(100);
80 
81 	do {
82 		regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
83 		if (readback & TEGRA20_AC97_STATUS1_CODEC1_RDY)
84 			break;
85 		usleep_range(1000, 2000);
86 	} while (!time_after(jiffies, timeout));
87 }
88 
89 static unsigned short tegra20_ac97_codec_read(struct snd_ac97 *ac97_snd,
90 					      unsigned short reg)
91 {
92 	u32 readback;
93 	unsigned long timeout;
94 
95 	regmap_write(workdata->regmap, TEGRA20_AC97_CMD,
96 		     (((reg | 0x80) << TEGRA20_AC97_CMD_CMD_ADDR_SHIFT) &
97 		      TEGRA20_AC97_CMD_CMD_ADDR_MASK) |
98 		     TEGRA20_AC97_CMD_BUSY);
99 
100 	timeout = jiffies + msecs_to_jiffies(100);
101 
102 	do {
103 		regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
104 		if (readback & TEGRA20_AC97_STATUS1_STA_VALID1)
105 			break;
106 		usleep_range(1000, 2000);
107 	} while (!time_after(jiffies, timeout));
108 
109 	return ((readback & TEGRA20_AC97_STATUS1_STA_DATA1_MASK) >>
110 		TEGRA20_AC97_STATUS1_STA_DATA1_SHIFT);
111 }
112 
113 static void tegra20_ac97_codec_write(struct snd_ac97 *ac97_snd,
114 				     unsigned short reg, unsigned short val)
115 {
116 	u32 readback;
117 	unsigned long timeout;
118 
119 	regmap_write(workdata->regmap, TEGRA20_AC97_CMD,
120 		     ((reg << TEGRA20_AC97_CMD_CMD_ADDR_SHIFT) &
121 		      TEGRA20_AC97_CMD_CMD_ADDR_MASK) |
122 		     ((val << TEGRA20_AC97_CMD_CMD_DATA_SHIFT) &
123 		      TEGRA20_AC97_CMD_CMD_DATA_MASK) |
124 		     TEGRA20_AC97_CMD_BUSY);
125 
126 	timeout = jiffies + msecs_to_jiffies(100);
127 
128 	do {
129 		regmap_read(workdata->regmap, TEGRA20_AC97_CMD, &readback);
130 		if (!(readback & TEGRA20_AC97_CMD_BUSY))
131 			break;
132 		usleep_range(1000, 2000);
133 	} while (!time_after(jiffies, timeout));
134 }
135 
136 static struct snd_ac97_bus_ops tegra20_ac97_ops = {
137 	.read		= tegra20_ac97_codec_read,
138 	.write		= tegra20_ac97_codec_write,
139 	.reset		= tegra20_ac97_codec_reset,
140 	.warm_reset	= tegra20_ac97_codec_warm_reset,
141 };
142 
143 static inline void tegra20_ac97_start_playback(struct tegra20_ac97 *ac97)
144 {
145 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
146 			   TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN,
147 			   TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN);
148 
149 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_CTRL,
150 			   TEGRA20_AC97_CTRL_PCM_DAC_EN |
151 			   TEGRA20_AC97_CTRL_STM_EN,
152 			   TEGRA20_AC97_CTRL_PCM_DAC_EN |
153 			   TEGRA20_AC97_CTRL_STM_EN);
154 }
155 
156 static inline void tegra20_ac97_stop_playback(struct tegra20_ac97 *ac97)
157 {
158 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
159 			   TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN, 0);
160 
161 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_CTRL,
162 			   TEGRA20_AC97_CTRL_PCM_DAC_EN, 0);
163 }
164 
165 static inline void tegra20_ac97_start_capture(struct tegra20_ac97 *ac97)
166 {
167 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
168 			   TEGRA20_AC97_FIFO_SCR_REC_FULL_EN,
169 			   TEGRA20_AC97_FIFO_SCR_REC_FULL_EN);
170 }
171 
172 static inline void tegra20_ac97_stop_capture(struct tegra20_ac97 *ac97)
173 {
174 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
175 			   TEGRA20_AC97_FIFO_SCR_REC_FULL_EN, 0);
176 }
177 
178 static int tegra20_ac97_trigger(struct snd_pcm_substream *substream, int cmd,
179 				struct snd_soc_dai *dai)
180 {
181 	struct tegra20_ac97 *ac97 = snd_soc_dai_get_drvdata(dai);
182 
183 	switch (cmd) {
184 	case SNDRV_PCM_TRIGGER_START:
185 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
186 	case SNDRV_PCM_TRIGGER_RESUME:
187 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
188 			tegra20_ac97_start_playback(ac97);
189 		else
190 			tegra20_ac97_start_capture(ac97);
191 		break;
192 	case SNDRV_PCM_TRIGGER_STOP:
193 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
194 	case SNDRV_PCM_TRIGGER_SUSPEND:
195 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
196 			tegra20_ac97_stop_playback(ac97);
197 		else
198 			tegra20_ac97_stop_capture(ac97);
199 		break;
200 	default:
201 		return -EINVAL;
202 	}
203 
204 	return 0;
205 }
206 
207 static const struct snd_soc_dai_ops tegra20_ac97_dai_ops = {
208 	.trigger	= tegra20_ac97_trigger,
209 };
210 
211 static int tegra20_ac97_probe(struct snd_soc_dai *dai)
212 {
213 	struct tegra20_ac97 *ac97 = snd_soc_dai_get_drvdata(dai);
214 
215 	dai->capture_dma_data = &ac97->capture_dma_data;
216 	dai->playback_dma_data = &ac97->playback_dma_data;
217 
218 	return 0;
219 }
220 
221 static struct snd_soc_dai_driver tegra20_ac97_dai = {
222 	.name = "tegra-ac97-pcm",
223 	.probe = tegra20_ac97_probe,
224 	.playback = {
225 		.stream_name = "PCM Playback",
226 		.channels_min = 2,
227 		.channels_max = 2,
228 		.rates = SNDRV_PCM_RATE_8000_48000,
229 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
230 	},
231 	.capture = {
232 		.stream_name = "PCM Capture",
233 		.channels_min = 2,
234 		.channels_max = 2,
235 		.rates = SNDRV_PCM_RATE_8000_48000,
236 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
237 	},
238 	.ops = &tegra20_ac97_dai_ops,
239 };
240 
241 static const struct snd_soc_component_driver tegra20_ac97_component = {
242 	.name		= DRV_NAME,
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 		return PTR_ERR(ac97->reset);
321 	}
322 
323 	ac97->clk_ac97 = devm_clk_get(&pdev->dev, NULL);
324 	if (IS_ERR(ac97->clk_ac97)) {
325 		dev_err(&pdev->dev, "Can't retrieve ac97 clock\n");
326 		ret = PTR_ERR(ac97->clk_ac97);
327 		goto err;
328 	}
329 
330 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
331 	regs = devm_ioremap_resource(&pdev->dev, 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 		goto err_clk_put;
357 	}
358 
359 	ac97->sync_gpio = of_get_named_gpio(pdev->dev.of_node,
360 					    "nvidia,codec-sync-gpio", 0);
361 	if (!gpio_is_valid(ac97->sync_gpio)) {
362 		dev_err(&pdev->dev, "no codec-sync GPIO supplied\n");
363 		goto err_clk_put;
364 	}
365 
366 	ac97->capture_dma_data.addr = mem->start + TEGRA20_AC97_FIFO_RX1;
367 	ac97->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
368 	ac97->capture_dma_data.maxburst = 4;
369 
370 	ac97->playback_dma_data.addr = mem->start + TEGRA20_AC97_FIFO_TX1;
371 	ac97->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
372 	ac97->playback_dma_data.maxburst = 4;
373 
374 	ret = reset_control_assert(ac97->reset);
375 	if (ret) {
376 		dev_err(&pdev->dev, "Failed to assert AC'97 reset: %d\n", ret);
377 		goto err_clk_put;
378 	}
379 
380 	ret = clk_prepare_enable(ac97->clk_ac97);
381 	if (ret) {
382 		dev_err(&pdev->dev, "clk_enable failed: %d\n", ret);
383 		goto err_clk_put;
384 	}
385 
386 	usleep_range(10, 100);
387 
388 	ret = reset_control_deassert(ac97->reset);
389 	if (ret) {
390 		dev_err(&pdev->dev, "Failed to deassert AC'97 reset: %d\n", ret);
391 		goto err_clk_disable_unprepare;
392 	}
393 
394 	ret = snd_soc_set_ac97_ops(&tegra20_ac97_ops);
395 	if (ret) {
396 		dev_err(&pdev->dev, "Failed to set AC'97 ops: %d\n", ret);
397 		goto err_clk_disable_unprepare;
398 	}
399 
400 	ret = snd_soc_register_component(&pdev->dev, &tegra20_ac97_component,
401 					 &tegra20_ac97_dai, 1);
402 	if (ret) {
403 		dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
404 		ret = -ENOMEM;
405 		goto err_clk_disable_unprepare;
406 	}
407 
408 	ret = tegra_pcm_platform_register(&pdev->dev);
409 	if (ret) {
410 		dev_err(&pdev->dev, "Could not register PCM: %d\n", ret);
411 		goto err_unregister_component;
412 	}
413 
414 	/* XXX: crufty ASoC AC97 API - only one AC97 codec allowed */
415 	workdata = ac97;
416 
417 	return 0;
418 
419 err_unregister_component:
420 	snd_soc_unregister_component(&pdev->dev);
421 err_clk_disable_unprepare:
422 	clk_disable_unprepare(ac97->clk_ac97);
423 err_clk_put:
424 err:
425 	snd_soc_set_ac97_ops(NULL);
426 	return ret;
427 }
428 
429 static int tegra20_ac97_platform_remove(struct platform_device *pdev)
430 {
431 	struct tegra20_ac97 *ac97 = dev_get_drvdata(&pdev->dev);
432 
433 	tegra_pcm_platform_unregister(&pdev->dev);
434 	snd_soc_unregister_component(&pdev->dev);
435 
436 	clk_disable_unprepare(ac97->clk_ac97);
437 
438 	snd_soc_set_ac97_ops(NULL);
439 
440 	return 0;
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 = 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