xref: /openbmc/linux/sound/soc/soc-ac97.c (revision 32981ea5)
1 /*
2  * soc-ac97.c  --  ALSA SoC Audio Layer AC97 support
3  *
4  * Copyright 2005 Wolfson Microelectronics PLC.
5  * Copyright 2005 Openedhand Ltd.
6  * Copyright (C) 2010 Slimlogic Ltd.
7  * Copyright (C) 2010 Texas Instruments Inc.
8  *
9  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
10  *         with code, comments and ideas from :-
11  *         Richard Purdie <richard@openedhand.com>
12  *
13  *  This program is free software; you can redistribute  it and/or modify it
14  *  under  the terms of  the GNU General  Public License as published by the
15  *  Free Software Foundation;  either version 2 of the  License, or (at your
16  *  option) any later version.
17  */
18 
19 #include <linux/ctype.h>
20 #include <linux/delay.h>
21 #include <linux/export.h>
22 #include <linux/gpio.h>
23 #include <linux/gpio/driver.h>
24 #include <linux/init.h>
25 #include <linux/of_gpio.h>
26 #include <linux/of.h>
27 #include <linux/pinctrl/consumer.h>
28 #include <linux/slab.h>
29 #include <sound/ac97_codec.h>
30 #include <sound/soc.h>
31 
32 struct snd_ac97_reset_cfg {
33 	struct pinctrl *pctl;
34 	struct pinctrl_state *pstate_reset;
35 	struct pinctrl_state *pstate_warm_reset;
36 	struct pinctrl_state *pstate_run;
37 	int gpio_sdata;
38 	int gpio_sync;
39 	int gpio_reset;
40 };
41 
42 struct snd_ac97_gpio_priv {
43 #ifdef CONFIG_GPIOLIB
44 	struct gpio_chip gpio_chip;
45 #endif
46 	unsigned int gpios_set;
47 	struct snd_soc_codec *codec;
48 };
49 
50 static struct snd_ac97_bus soc_ac97_bus = {
51 	.ops = NULL, /* Gets initialized in snd_soc_set_ac97_ops() */
52 };
53 
54 static void soc_ac97_device_release(struct device *dev)
55 {
56 	kfree(to_ac97_t(dev));
57 }
58 
59 #ifdef CONFIG_GPIOLIB
60 static inline struct snd_soc_codec *gpio_to_codec(struct gpio_chip *chip)
61 {
62 	struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
63 
64 	return gpio_priv->codec;
65 }
66 
67 static int snd_soc_ac97_gpio_request(struct gpio_chip *chip, unsigned offset)
68 {
69 	if (offset >= AC97_NUM_GPIOS)
70 		return -EINVAL;
71 
72 	return 0;
73 }
74 
75 static int snd_soc_ac97_gpio_direction_in(struct gpio_chip *chip,
76 					  unsigned offset)
77 {
78 	struct snd_soc_codec *codec = gpio_to_codec(chip);
79 
80 	dev_dbg(codec->dev, "set gpio %d to output\n", offset);
81 	return snd_soc_update_bits(codec, AC97_GPIO_CFG,
82 				   1 << offset, 1 << offset);
83 }
84 
85 static int snd_soc_ac97_gpio_get(struct gpio_chip *chip, unsigned offset)
86 {
87 	struct snd_soc_codec *codec = gpio_to_codec(chip);
88 	int ret;
89 
90 	ret = snd_soc_read(codec, AC97_GPIO_STATUS);
91 	dev_dbg(codec->dev, "get gpio %d : %d\n", offset,
92 		ret < 0 ? ret : ret & (1 << offset));
93 
94 	return ret < 0 ? ret : !!(ret & (1 << offset));
95 }
96 
97 static void snd_soc_ac97_gpio_set(struct gpio_chip *chip, unsigned offset,
98 				  int value)
99 {
100 	struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
101 	struct snd_soc_codec *codec = gpio_to_codec(chip);
102 
103 	gpio_priv->gpios_set &= ~(1 << offset);
104 	gpio_priv->gpios_set |= (!!value) << offset;
105 	snd_soc_write(codec, AC97_GPIO_STATUS, gpio_priv->gpios_set);
106 	dev_dbg(codec->dev, "set gpio %d to %d\n", offset, !!value);
107 }
108 
109 static int snd_soc_ac97_gpio_direction_out(struct gpio_chip *chip,
110 				     unsigned offset, int value)
111 {
112 	struct snd_soc_codec *codec = gpio_to_codec(chip);
113 
114 	dev_dbg(codec->dev, "set gpio %d to output\n", offset);
115 	snd_soc_ac97_gpio_set(chip, offset, value);
116 	return snd_soc_update_bits(codec, AC97_GPIO_CFG, 1 << offset, 0);
117 }
118 
119 static struct gpio_chip snd_soc_ac97_gpio_chip = {
120 	.label			= "snd_soc_ac97",
121 	.owner			= THIS_MODULE,
122 	.request		= snd_soc_ac97_gpio_request,
123 	.direction_input	= snd_soc_ac97_gpio_direction_in,
124 	.get			= snd_soc_ac97_gpio_get,
125 	.direction_output	= snd_soc_ac97_gpio_direction_out,
126 	.set			= snd_soc_ac97_gpio_set,
127 	.can_sleep		= 1,
128 };
129 
130 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
131 				  struct snd_soc_codec *codec)
132 {
133 	struct snd_ac97_gpio_priv *gpio_priv;
134 	int ret;
135 
136 	gpio_priv = devm_kzalloc(codec->dev, sizeof(*gpio_priv), GFP_KERNEL);
137 	if (!gpio_priv)
138 		return -ENOMEM;
139 	ac97->gpio_priv = gpio_priv;
140 	gpio_priv->codec = codec;
141 	gpio_priv->gpio_chip = snd_soc_ac97_gpio_chip;
142 	gpio_priv->gpio_chip.ngpio = AC97_NUM_GPIOS;
143 	gpio_priv->gpio_chip.parent = codec->dev;
144 	gpio_priv->gpio_chip.base = -1;
145 
146 	ret = gpiochip_add_data(&gpio_priv->gpio_chip, gpio_priv);
147 	if (ret != 0)
148 		dev_err(codec->dev, "Failed to add GPIOs: %d\n", ret);
149 	return ret;
150 }
151 
152 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
153 {
154 	gpiochip_remove(&ac97->gpio_priv->gpio_chip);
155 }
156 #else
157 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
158 				  struct snd_soc_codec *codec)
159 {
160 	return 0;
161 }
162 
163 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
164 {
165 }
166 #endif
167 
168 /**
169  * snd_soc_alloc_ac97_codec() - Allocate new a AC'97 device
170  * @codec: The CODEC for which to create the AC'97 device
171  *
172  * Allocated a new snd_ac97 device and intializes it, but does not yet register
173  * it. The caller is responsible to either call device_add(&ac97->dev) to
174  * register the device, or to call put_device(&ac97->dev) to free the device.
175  *
176  * Returns: A snd_ac97 device or a PTR_ERR in case of an error.
177  */
178 struct snd_ac97 *snd_soc_alloc_ac97_codec(struct snd_soc_codec *codec)
179 {
180 	struct snd_ac97 *ac97;
181 
182 	ac97 = kzalloc(sizeof(struct snd_ac97), GFP_KERNEL);
183 	if (ac97 == NULL)
184 		return ERR_PTR(-ENOMEM);
185 
186 	ac97->bus = &soc_ac97_bus;
187 	ac97->num = 0;
188 
189 	ac97->dev.bus = &ac97_bus_type;
190 	ac97->dev.parent = codec->component.card->dev;
191 	ac97->dev.release = soc_ac97_device_release;
192 
193 	dev_set_name(&ac97->dev, "%d-%d:%s",
194 		     codec->component.card->snd_card->number, 0,
195 		     codec->component.name);
196 
197 	device_initialize(&ac97->dev);
198 
199 	return ac97;
200 }
201 EXPORT_SYMBOL(snd_soc_alloc_ac97_codec);
202 
203 /**
204  * snd_soc_new_ac97_codec - initailise AC97 device
205  * @codec: audio codec
206  * @id: The expected device ID
207  * @id_mask: Mask that is applied to the device ID before comparing with @id
208  *
209  * Initialises AC97 codec resources for use by ad-hoc devices only.
210  *
211  * If @id is not 0 this function will reset the device, then read the ID from
212  * the device and check if it matches the expected ID. If it doesn't match an
213  * error will be returned and device will not be registered.
214  *
215  * Returns: A PTR_ERR() on failure or a valid snd_ac97 struct on success.
216  */
217 struct snd_ac97 *snd_soc_new_ac97_codec(struct snd_soc_codec *codec,
218 	unsigned int id, unsigned int id_mask)
219 {
220 	struct snd_ac97 *ac97;
221 	int ret;
222 
223 	ac97 = snd_soc_alloc_ac97_codec(codec);
224 	if (IS_ERR(ac97))
225 		return ac97;
226 
227 	if (id) {
228 		ret = snd_ac97_reset(ac97, false, id, id_mask);
229 		if (ret < 0) {
230 			dev_err(codec->dev, "Failed to reset AC97 device: %d\n",
231 				ret);
232 			goto err_put_device;
233 		}
234 	}
235 
236 	ret = device_add(&ac97->dev);
237 	if (ret)
238 		goto err_put_device;
239 
240 	ret = snd_soc_ac97_init_gpio(ac97, codec);
241 	if (ret)
242 		goto err_put_device;
243 
244 	return ac97;
245 
246 err_put_device:
247 	put_device(&ac97->dev);
248 	return ERR_PTR(ret);
249 }
250 EXPORT_SYMBOL_GPL(snd_soc_new_ac97_codec);
251 
252 /**
253  * snd_soc_free_ac97_codec - free AC97 codec device
254  * @codec: audio codec
255  *
256  * Frees AC97 codec device resources.
257  */
258 void snd_soc_free_ac97_codec(struct snd_ac97 *ac97)
259 {
260 	snd_soc_ac97_free_gpio(ac97);
261 	device_del(&ac97->dev);
262 	ac97->bus = NULL;
263 	put_device(&ac97->dev);
264 }
265 EXPORT_SYMBOL_GPL(snd_soc_free_ac97_codec);
266 
267 static struct snd_ac97_reset_cfg snd_ac97_rst_cfg;
268 
269 static void snd_soc_ac97_warm_reset(struct snd_ac97 *ac97)
270 {
271 	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
272 
273 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_warm_reset);
274 
275 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 1);
276 
277 	udelay(10);
278 
279 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
280 
281 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
282 	msleep(2);
283 }
284 
285 static void snd_soc_ac97_reset(struct snd_ac97 *ac97)
286 {
287 	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
288 
289 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_reset);
290 
291 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
292 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sdata, 0);
293 	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 0);
294 
295 	udelay(10);
296 
297 	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 1);
298 
299 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
300 	msleep(2);
301 }
302 
303 static int snd_soc_ac97_parse_pinctl(struct device *dev,
304 		struct snd_ac97_reset_cfg *cfg)
305 {
306 	struct pinctrl *p;
307 	struct pinctrl_state *state;
308 	int gpio;
309 	int ret;
310 
311 	p = devm_pinctrl_get(dev);
312 	if (IS_ERR(p)) {
313 		dev_err(dev, "Failed to get pinctrl\n");
314 		return PTR_ERR(p);
315 	}
316 	cfg->pctl = p;
317 
318 	state = pinctrl_lookup_state(p, "ac97-reset");
319 	if (IS_ERR(state)) {
320 		dev_err(dev, "Can't find pinctrl state ac97-reset\n");
321 		return PTR_ERR(state);
322 	}
323 	cfg->pstate_reset = state;
324 
325 	state = pinctrl_lookup_state(p, "ac97-warm-reset");
326 	if (IS_ERR(state)) {
327 		dev_err(dev, "Can't find pinctrl state ac97-warm-reset\n");
328 		return PTR_ERR(state);
329 	}
330 	cfg->pstate_warm_reset = state;
331 
332 	state = pinctrl_lookup_state(p, "ac97-running");
333 	if (IS_ERR(state)) {
334 		dev_err(dev, "Can't find pinctrl state ac97-running\n");
335 		return PTR_ERR(state);
336 	}
337 	cfg->pstate_run = state;
338 
339 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 0);
340 	if (gpio < 0) {
341 		dev_err(dev, "Can't find ac97-sync gpio\n");
342 		return gpio;
343 	}
344 	ret = devm_gpio_request(dev, gpio, "AC97 link sync");
345 	if (ret) {
346 		dev_err(dev, "Failed requesting ac97-sync gpio\n");
347 		return ret;
348 	}
349 	cfg->gpio_sync = gpio;
350 
351 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 1);
352 	if (gpio < 0) {
353 		dev_err(dev, "Can't find ac97-sdata gpio %d\n", gpio);
354 		return gpio;
355 	}
356 	ret = devm_gpio_request(dev, gpio, "AC97 link sdata");
357 	if (ret) {
358 		dev_err(dev, "Failed requesting ac97-sdata gpio\n");
359 		return ret;
360 	}
361 	cfg->gpio_sdata = gpio;
362 
363 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
364 	if (gpio < 0) {
365 		dev_err(dev, "Can't find ac97-reset gpio\n");
366 		return gpio;
367 	}
368 	ret = devm_gpio_request(dev, gpio, "AC97 link reset");
369 	if (ret) {
370 		dev_err(dev, "Failed requesting ac97-reset gpio\n");
371 		return ret;
372 	}
373 	cfg->gpio_reset = gpio;
374 
375 	return 0;
376 }
377 
378 struct snd_ac97_bus_ops *soc_ac97_ops;
379 EXPORT_SYMBOL_GPL(soc_ac97_ops);
380 
381 int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops)
382 {
383 	if (ops == soc_ac97_ops)
384 		return 0;
385 
386 	if (soc_ac97_ops && ops)
387 		return -EBUSY;
388 
389 	soc_ac97_ops = ops;
390 	soc_ac97_bus.ops = ops;
391 
392 	return 0;
393 }
394 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops);
395 
396 /**
397  * snd_soc_set_ac97_ops_of_reset - Set ac97 ops with generic ac97 reset functions
398  *
399  * This function sets the reset and warm_reset properties of ops and parses
400  * the device node of pdev to get pinctrl states and gpio numbers to use.
401  */
402 int snd_soc_set_ac97_ops_of_reset(struct snd_ac97_bus_ops *ops,
403 		struct platform_device *pdev)
404 {
405 	struct device *dev = &pdev->dev;
406 	struct snd_ac97_reset_cfg cfg;
407 	int ret;
408 
409 	ret = snd_soc_ac97_parse_pinctl(dev, &cfg);
410 	if (ret)
411 		return ret;
412 
413 	ret = snd_soc_set_ac97_ops(ops);
414 	if (ret)
415 		return ret;
416 
417 	ops->warm_reset = snd_soc_ac97_warm_reset;
418 	ops->reset = snd_soc_ac97_reset;
419 
420 	snd_ac97_rst_cfg = cfg;
421 	return 0;
422 }
423 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops_of_reset);
424