xref: /openbmc/linux/sound/soc/tegra/tegra20_ac97.c (revision 8fdf9062)
1 /*
2  * tegra20_ac97.c - Tegra20 AC97 platform driver
3  *
4  * Copyright (c) 2012 Lucas Stach <dev@lynxeye.de>
5  *
6  * Partly based on code copyright/by:
7  *
8  * Copyright (c) 2011,2012 Toradex Inc.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License
12  * version 2 as published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  */
20 
21 #include <linux/clk.h>
22 #include <linux/delay.h>
23 #include <linux/device.h>
24 #include <linux/gpio.h>
25 #include <linux/io.h>
26 #include <linux/jiffies.h>
27 #include <linux/module.h>
28 #include <linux/of.h>
29 #include <linux/of_gpio.h>
30 #include <linux/platform_device.h>
31 #include <linux/pm_runtime.h>
32 #include <linux/regmap.h>
33 #include <linux/slab.h>
34 #include <sound/core.h>
35 #include <sound/pcm.h>
36 #include <sound/pcm_params.h>
37 #include <sound/soc.h>
38 #include <sound/dmaengine_pcm.h>
39 
40 #include "tegra20_ac97.h"
41 
42 #define DRV_NAME "tegra20-ac97"
43 
44 static struct tegra20_ac97 *workdata;
45 
46 static void tegra20_ac97_codec_reset(struct snd_ac97 *ac97)
47 {
48 	u32 readback;
49 	unsigned long timeout;
50 
51 	/* reset line is not driven by DAC pad group, have to toggle GPIO */
52 	gpio_set_value(workdata->reset_gpio, 0);
53 	udelay(2);
54 
55 	gpio_set_value(workdata->reset_gpio, 1);
56 	udelay(2);
57 
58 	timeout = jiffies + msecs_to_jiffies(100);
59 
60 	do {
61 		regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
62 		if (readback & TEGRA20_AC97_STATUS1_CODEC1_RDY)
63 			break;
64 		usleep_range(1000, 2000);
65 	} while (!time_after(jiffies, timeout));
66 }
67 
68 static void tegra20_ac97_codec_warm_reset(struct snd_ac97 *ac97)
69 {
70 	u32 readback;
71 	unsigned long timeout;
72 
73 	/*
74 	 * although sync line is driven by the DAC pad group warm reset using
75 	 * the controller cmd is not working, have to toggle sync line
76 	 * manually.
77 	 */
78 	gpio_request(workdata->sync_gpio, "codec-sync");
79 
80 	gpio_direction_output(workdata->sync_gpio, 1);
81 
82 	udelay(2);
83 	gpio_set_value(workdata->sync_gpio, 0);
84 	udelay(2);
85 	gpio_free(workdata->sync_gpio);
86 
87 	timeout = jiffies + msecs_to_jiffies(100);
88 
89 	do {
90 		regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
91 		if (readback & TEGRA20_AC97_STATUS1_CODEC1_RDY)
92 			break;
93 		usleep_range(1000, 2000);
94 	} while (!time_after(jiffies, timeout));
95 }
96 
97 static unsigned short tegra20_ac97_codec_read(struct snd_ac97 *ac97_snd,
98 					      unsigned short reg)
99 {
100 	u32 readback;
101 	unsigned long timeout;
102 
103 	regmap_write(workdata->regmap, TEGRA20_AC97_CMD,
104 		     (((reg | 0x80) << TEGRA20_AC97_CMD_CMD_ADDR_SHIFT) &
105 		      TEGRA20_AC97_CMD_CMD_ADDR_MASK) |
106 		     TEGRA20_AC97_CMD_BUSY);
107 
108 	timeout = jiffies + msecs_to_jiffies(100);
109 
110 	do {
111 		regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
112 		if (readback & TEGRA20_AC97_STATUS1_STA_VALID1)
113 			break;
114 		usleep_range(1000, 2000);
115 	} while (!time_after(jiffies, timeout));
116 
117 	return ((readback & TEGRA20_AC97_STATUS1_STA_DATA1_MASK) >>
118 		TEGRA20_AC97_STATUS1_STA_DATA1_SHIFT);
119 }
120 
121 static void tegra20_ac97_codec_write(struct snd_ac97 *ac97_snd,
122 				     unsigned short reg, unsigned short val)
123 {
124 	u32 readback;
125 	unsigned long timeout;
126 
127 	regmap_write(workdata->regmap, TEGRA20_AC97_CMD,
128 		     ((reg << TEGRA20_AC97_CMD_CMD_ADDR_SHIFT) &
129 		      TEGRA20_AC97_CMD_CMD_ADDR_MASK) |
130 		     ((val << TEGRA20_AC97_CMD_CMD_DATA_SHIFT) &
131 		      TEGRA20_AC97_CMD_CMD_DATA_MASK) |
132 		     TEGRA20_AC97_CMD_BUSY);
133 
134 	timeout = jiffies + msecs_to_jiffies(100);
135 
136 	do {
137 		regmap_read(workdata->regmap, TEGRA20_AC97_CMD, &readback);
138 		if (!(readback & TEGRA20_AC97_CMD_BUSY))
139 			break;
140 		usleep_range(1000, 2000);
141 	} while (!time_after(jiffies, timeout));
142 }
143 
144 static struct snd_ac97_bus_ops tegra20_ac97_ops = {
145 	.read		= tegra20_ac97_codec_read,
146 	.write		= tegra20_ac97_codec_write,
147 	.reset		= tegra20_ac97_codec_reset,
148 	.warm_reset	= tegra20_ac97_codec_warm_reset,
149 };
150 
151 static inline void tegra20_ac97_start_playback(struct tegra20_ac97 *ac97)
152 {
153 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
154 			   TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN,
155 			   TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN);
156 
157 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_CTRL,
158 			   TEGRA20_AC97_CTRL_PCM_DAC_EN |
159 			   TEGRA20_AC97_CTRL_STM_EN,
160 			   TEGRA20_AC97_CTRL_PCM_DAC_EN |
161 			   TEGRA20_AC97_CTRL_STM_EN);
162 }
163 
164 static inline void tegra20_ac97_stop_playback(struct tegra20_ac97 *ac97)
165 {
166 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
167 			   TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN, 0);
168 
169 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_CTRL,
170 			   TEGRA20_AC97_CTRL_PCM_DAC_EN, 0);
171 }
172 
173 static inline void tegra20_ac97_start_capture(struct tegra20_ac97 *ac97)
174 {
175 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
176 			   TEGRA20_AC97_FIFO_SCR_REC_FULL_EN,
177 			   TEGRA20_AC97_FIFO_SCR_REC_FULL_EN);
178 }
179 
180 static inline void tegra20_ac97_stop_capture(struct tegra20_ac97 *ac97)
181 {
182 	regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
183 			   TEGRA20_AC97_FIFO_SCR_REC_FULL_EN, 0);
184 }
185 
186 static int tegra20_ac97_trigger(struct snd_pcm_substream *substream, int cmd,
187 				struct snd_soc_dai *dai)
188 {
189 	struct tegra20_ac97 *ac97 = snd_soc_dai_get_drvdata(dai);
190 
191 	switch (cmd) {
192 	case SNDRV_PCM_TRIGGER_START:
193 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
194 	case SNDRV_PCM_TRIGGER_RESUME:
195 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
196 			tegra20_ac97_start_playback(ac97);
197 		else
198 			tegra20_ac97_start_capture(ac97);
199 		break;
200 	case SNDRV_PCM_TRIGGER_STOP:
201 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
202 	case SNDRV_PCM_TRIGGER_SUSPEND:
203 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
204 			tegra20_ac97_stop_playback(ac97);
205 		else
206 			tegra20_ac97_stop_capture(ac97);
207 		break;
208 	default:
209 		return -EINVAL;
210 	}
211 
212 	return 0;
213 }
214 
215 static const struct snd_soc_dai_ops tegra20_ac97_dai_ops = {
216 	.trigger	= tegra20_ac97_trigger,
217 };
218 
219 static int tegra20_ac97_probe(struct snd_soc_dai *dai)
220 {
221 	struct tegra20_ac97 *ac97 = snd_soc_dai_get_drvdata(dai);
222 
223 	dai->capture_dma_data = &ac97->capture_dma_data;
224 	dai->playback_dma_data = &ac97->playback_dma_data;
225 
226 	return 0;
227 }
228 
229 static struct snd_soc_dai_driver tegra20_ac97_dai = {
230 	.name = "tegra-ac97-pcm",
231 	.bus_control = true,
232 	.probe = tegra20_ac97_probe,
233 	.playback = {
234 		.stream_name = "PCM Playback",
235 		.channels_min = 2,
236 		.channels_max = 2,
237 		.rates = SNDRV_PCM_RATE_8000_48000,
238 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
239 	},
240 	.capture = {
241 		.stream_name = "PCM Capture",
242 		.channels_min = 2,
243 		.channels_max = 2,
244 		.rates = SNDRV_PCM_RATE_8000_48000,
245 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
246 	},
247 	.ops = &tegra20_ac97_dai_ops,
248 };
249 
250 static const struct snd_soc_component_driver tegra20_ac97_component = {
251 	.name		= DRV_NAME,
252 };
253 
254 static bool tegra20_ac97_wr_rd_reg(struct device *dev, unsigned int reg)
255 {
256 	switch (reg) {
257 	case TEGRA20_AC97_CTRL:
258 	case TEGRA20_AC97_CMD:
259 	case TEGRA20_AC97_STATUS1:
260 	case TEGRA20_AC97_FIFO1_SCR:
261 	case TEGRA20_AC97_FIFO_TX1:
262 	case TEGRA20_AC97_FIFO_RX1:
263 		return true;
264 	default:
265 		break;
266 	}
267 
268 	return false;
269 }
270 
271 static bool tegra20_ac97_volatile_reg(struct device *dev, unsigned int reg)
272 {
273 	switch (reg) {
274 	case TEGRA20_AC97_STATUS1:
275 	case TEGRA20_AC97_FIFO1_SCR:
276 	case TEGRA20_AC97_FIFO_TX1:
277 	case TEGRA20_AC97_FIFO_RX1:
278 		return true;
279 	default:
280 		break;
281 	}
282 
283 	return false;
284 }
285 
286 static bool tegra20_ac97_precious_reg(struct device *dev, unsigned int reg)
287 {
288 	switch (reg) {
289 	case TEGRA20_AC97_FIFO_TX1:
290 	case TEGRA20_AC97_FIFO_RX1:
291 		return true;
292 	default:
293 		break;
294 	}
295 
296 	return false;
297 }
298 
299 static const struct regmap_config tegra20_ac97_regmap_config = {
300 	.reg_bits = 32,
301 	.reg_stride = 4,
302 	.val_bits = 32,
303 	.max_register = TEGRA20_AC97_FIFO_RX1,
304 	.writeable_reg = tegra20_ac97_wr_rd_reg,
305 	.readable_reg = tegra20_ac97_wr_rd_reg,
306 	.volatile_reg = tegra20_ac97_volatile_reg,
307 	.precious_reg = tegra20_ac97_precious_reg,
308 	.cache_type = REGCACHE_FLAT,
309 };
310 
311 static int tegra20_ac97_platform_probe(struct platform_device *pdev)
312 {
313 	struct tegra20_ac97 *ac97;
314 	struct resource *mem;
315 	void __iomem *regs;
316 	int ret = 0;
317 
318 	ac97 = devm_kzalloc(&pdev->dev, sizeof(struct tegra20_ac97),
319 			    GFP_KERNEL);
320 	if (!ac97) {
321 		ret = -ENOMEM;
322 		goto err;
323 	}
324 	dev_set_drvdata(&pdev->dev, ac97);
325 
326 	ac97->clk_ac97 = devm_clk_get(&pdev->dev, NULL);
327 	if (IS_ERR(ac97->clk_ac97)) {
328 		dev_err(&pdev->dev, "Can't retrieve ac97 clock\n");
329 		ret = PTR_ERR(ac97->clk_ac97);
330 		goto err;
331 	}
332 
333 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
334 	regs = devm_ioremap_resource(&pdev->dev, mem);
335 	if (IS_ERR(regs)) {
336 		ret = PTR_ERR(regs);
337 		goto err_clk_put;
338 	}
339 
340 	ac97->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
341 					    &tegra20_ac97_regmap_config);
342 	if (IS_ERR(ac97->regmap)) {
343 		dev_err(&pdev->dev, "regmap init failed\n");
344 		ret = PTR_ERR(ac97->regmap);
345 		goto err_clk_put;
346 	}
347 
348 	ac97->reset_gpio = of_get_named_gpio(pdev->dev.of_node,
349 					     "nvidia,codec-reset-gpio", 0);
350 	if (gpio_is_valid(ac97->reset_gpio)) {
351 		ret = devm_gpio_request_one(&pdev->dev, ac97->reset_gpio,
352 					    GPIOF_OUT_INIT_HIGH, "codec-reset");
353 		if (ret) {
354 			dev_err(&pdev->dev, "could not get codec-reset GPIO\n");
355 			goto err_clk_put;
356 		}
357 	} else {
358 		dev_err(&pdev->dev, "no codec-reset GPIO supplied\n");
359 		goto err_clk_put;
360 	}
361 
362 	ac97->sync_gpio = of_get_named_gpio(pdev->dev.of_node,
363 					    "nvidia,codec-sync-gpio", 0);
364 	if (!gpio_is_valid(ac97->sync_gpio)) {
365 		dev_err(&pdev->dev, "no codec-sync GPIO supplied\n");
366 		goto err_clk_put;
367 	}
368 
369 	ac97->capture_dma_data.addr = mem->start + TEGRA20_AC97_FIFO_RX1;
370 	ac97->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
371 	ac97->capture_dma_data.maxburst = 4;
372 
373 	ac97->playback_dma_data.addr = mem->start + TEGRA20_AC97_FIFO_TX1;
374 	ac97->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
375 	ac97->playback_dma_data.maxburst = 4;
376 
377 	ret = clk_prepare_enable(ac97->clk_ac97);
378 	if (ret) {
379 		dev_err(&pdev->dev, "clk_enable failed: %d\n", ret);
380 		goto err_clk_put;
381 	}
382 
383 	ret = snd_soc_set_ac97_ops(&tegra20_ac97_ops);
384 	if (ret) {
385 		dev_err(&pdev->dev, "Failed to set AC'97 ops: %d\n", ret);
386 		goto err_clk_disable_unprepare;
387 	}
388 
389 	ret = snd_soc_register_component(&pdev->dev, &tegra20_ac97_component,
390 					 &tegra20_ac97_dai, 1);
391 	if (ret) {
392 		dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
393 		ret = -ENOMEM;
394 		goto err_clk_disable_unprepare;
395 	}
396 
397 	ret = tegra_pcm_platform_register(&pdev->dev);
398 	if (ret) {
399 		dev_err(&pdev->dev, "Could not register PCM: %d\n", ret);
400 		goto err_unregister_component;
401 	}
402 
403 	/* XXX: crufty ASoC AC97 API - only one AC97 codec allowed */
404 	workdata = ac97;
405 
406 	return 0;
407 
408 err_unregister_component:
409 	snd_soc_unregister_component(&pdev->dev);
410 err_clk_disable_unprepare:
411 	clk_disable_unprepare(ac97->clk_ac97);
412 err_clk_put:
413 err:
414 	snd_soc_set_ac97_ops(NULL);
415 	return ret;
416 }
417 
418 static int tegra20_ac97_platform_remove(struct platform_device *pdev)
419 {
420 	struct tegra20_ac97 *ac97 = dev_get_drvdata(&pdev->dev);
421 
422 	tegra_pcm_platform_unregister(&pdev->dev);
423 	snd_soc_unregister_component(&pdev->dev);
424 
425 	clk_disable_unprepare(ac97->clk_ac97);
426 
427 	snd_soc_set_ac97_ops(NULL);
428 
429 	return 0;
430 }
431 
432 static const struct of_device_id tegra20_ac97_of_match[] = {
433 	{ .compatible = "nvidia,tegra20-ac97", },
434 	{},
435 };
436 
437 static struct platform_driver tegra20_ac97_driver = {
438 	.driver = {
439 		.name = DRV_NAME,
440 		.of_match_table = tegra20_ac97_of_match,
441 	},
442 	.probe = tegra20_ac97_platform_probe,
443 	.remove = tegra20_ac97_platform_remove,
444 };
445 module_platform_driver(tegra20_ac97_driver);
446 
447 MODULE_AUTHOR("Lucas Stach");
448 MODULE_DESCRIPTION("Tegra20 AC97 ASoC driver");
449 MODULE_LICENSE("GPL v2");
450 MODULE_ALIAS("platform:" DRV_NAME);
451 MODULE_DEVICE_TABLE(of, tegra20_ac97_of_match);
452