xref: /linux/sound/soc/soc-ac97.c (revision 9bacbced0e32204deb8b9d011279f9beddd8c2ef)
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_component *component;
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_component *gpio_to_component(struct gpio_chip *chip)
61 {
62 	struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
63 
64 	return gpio_priv->component;
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_component *component = gpio_to_component(chip);
79 
80 	dev_dbg(component->dev, "set gpio %d to output\n", offset);
81 	return snd_soc_component_update_bits(component, 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_component *component = gpio_to_component(chip);
88 	int ret;
89 
90 	if (snd_soc_component_read(component, AC97_GPIO_STATUS, &ret) < 0)
91 		ret = -1;
92 
93 	dev_dbg(component->dev, "get gpio %d : %d\n", offset,
94 		ret < 0 ? ret : ret & (1 << offset));
95 
96 	return ret < 0 ? ret : !!(ret & (1 << offset));
97 }
98 
99 static void snd_soc_ac97_gpio_set(struct gpio_chip *chip, unsigned offset,
100 				  int value)
101 {
102 	struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
103 	struct snd_soc_component *component = gpio_to_component(chip);
104 
105 	gpio_priv->gpios_set &= ~(1 << offset);
106 	gpio_priv->gpios_set |= (!!value) << offset;
107 	snd_soc_component_write(component, AC97_GPIO_STATUS,
108 				gpio_priv->gpios_set);
109 	dev_dbg(component->dev, "set gpio %d to %d\n", offset, !!value);
110 }
111 
112 static int snd_soc_ac97_gpio_direction_out(struct gpio_chip *chip,
113 				     unsigned offset, int value)
114 {
115 	struct snd_soc_component *component = gpio_to_component(chip);
116 
117 	dev_dbg(component->dev, "set gpio %d to output\n", offset);
118 	snd_soc_ac97_gpio_set(chip, offset, value);
119 	return snd_soc_component_update_bits(component, AC97_GPIO_CFG,
120 					     1 << offset, 0);
121 }
122 
123 static const struct gpio_chip snd_soc_ac97_gpio_chip = {
124 	.label			= "snd_soc_ac97",
125 	.owner			= THIS_MODULE,
126 	.request		= snd_soc_ac97_gpio_request,
127 	.direction_input	= snd_soc_ac97_gpio_direction_in,
128 	.get			= snd_soc_ac97_gpio_get,
129 	.direction_output	= snd_soc_ac97_gpio_direction_out,
130 	.set			= snd_soc_ac97_gpio_set,
131 	.can_sleep		= 1,
132 };
133 
134 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
135 				  struct snd_soc_component *component)
136 {
137 	struct snd_ac97_gpio_priv *gpio_priv;
138 	int ret;
139 
140 	gpio_priv = devm_kzalloc(component->dev, sizeof(*gpio_priv), GFP_KERNEL);
141 	if (!gpio_priv)
142 		return -ENOMEM;
143 	ac97->gpio_priv = gpio_priv;
144 	gpio_priv->component = component;
145 	gpio_priv->gpio_chip = snd_soc_ac97_gpio_chip;
146 	gpio_priv->gpio_chip.ngpio = AC97_NUM_GPIOS;
147 	gpio_priv->gpio_chip.parent = component->dev;
148 	gpio_priv->gpio_chip.base = -1;
149 
150 	ret = gpiochip_add_data(&gpio_priv->gpio_chip, gpio_priv);
151 	if (ret != 0)
152 		dev_err(component->dev, "Failed to add GPIOs: %d\n", ret);
153 	return ret;
154 }
155 
156 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
157 {
158 	gpiochip_remove(&ac97->gpio_priv->gpio_chip);
159 }
160 #else
161 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
162 				  struct snd_soc_component *component)
163 {
164 	return 0;
165 }
166 
167 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
168 {
169 }
170 #endif
171 
172 /**
173  * snd_soc_alloc_ac97_component() - Allocate new a AC'97 device
174  * @component: The COMPONENT for which to create the AC'97 device
175  *
176  * Allocated a new snd_ac97 device and intializes it, but does not yet register
177  * it. The caller is responsible to either call device_add(&ac97->dev) to
178  * register the device, or to call put_device(&ac97->dev) to free the device.
179  *
180  * Returns: A snd_ac97 device or a PTR_ERR in case of an error.
181  */
182 struct snd_ac97 *snd_soc_alloc_ac97_component(struct snd_soc_component *component)
183 {
184 	struct snd_ac97 *ac97;
185 
186 	ac97 = kzalloc(sizeof(struct snd_ac97), GFP_KERNEL);
187 	if (ac97 == NULL)
188 		return ERR_PTR(-ENOMEM);
189 
190 	ac97->bus = &soc_ac97_bus;
191 	ac97->num = 0;
192 
193 	ac97->dev.bus = &ac97_bus_type;
194 	ac97->dev.parent = component->card->dev;
195 	ac97->dev.release = soc_ac97_device_release;
196 
197 	dev_set_name(&ac97->dev, "%d-%d:%s",
198 		     component->card->snd_card->number, 0,
199 		     component->name);
200 
201 	device_initialize(&ac97->dev);
202 
203 	return ac97;
204 }
205 EXPORT_SYMBOL(snd_soc_alloc_ac97_component);
206 
207 /**
208  * snd_soc_new_ac97_component - initailise AC97 device
209  * @component: audio component
210  * @id: The expected device ID
211  * @id_mask: Mask that is applied to the device ID before comparing with @id
212  *
213  * Initialises AC97 component resources for use by ad-hoc devices only.
214  *
215  * If @id is not 0 this function will reset the device, then read the ID from
216  * the device and check if it matches the expected ID. If it doesn't match an
217  * error will be returned and device will not be registered.
218  *
219  * Returns: A PTR_ERR() on failure or a valid snd_ac97 struct on success.
220  */
221 struct snd_ac97 *snd_soc_new_ac97_component(struct snd_soc_component *component,
222 	unsigned int id, unsigned int id_mask)
223 {
224 	struct snd_ac97 *ac97;
225 	int ret;
226 
227 	ac97 = snd_soc_alloc_ac97_component(component);
228 	if (IS_ERR(ac97))
229 		return ac97;
230 
231 	if (id) {
232 		ret = snd_ac97_reset(ac97, false, id, id_mask);
233 		if (ret < 0) {
234 			dev_err(component->dev, "Failed to reset AC97 device: %d\n",
235 				ret);
236 			goto err_put_device;
237 		}
238 	}
239 
240 	ret = device_add(&ac97->dev);
241 	if (ret)
242 		goto err_put_device;
243 
244 	ret = snd_soc_ac97_init_gpio(ac97, component);
245 	if (ret)
246 		goto err_put_device;
247 
248 	return ac97;
249 
250 err_put_device:
251 	put_device(&ac97->dev);
252 	return ERR_PTR(ret);
253 }
254 EXPORT_SYMBOL_GPL(snd_soc_new_ac97_component);
255 
256 /**
257  * snd_soc_free_ac97_component - free AC97 component device
258  * @ac97: snd_ac97 device to be freed
259  *
260  * Frees AC97 component device resources.
261  */
262 void snd_soc_free_ac97_component(struct snd_ac97 *ac97)
263 {
264 	snd_soc_ac97_free_gpio(ac97);
265 	device_del(&ac97->dev);
266 	ac97->bus = NULL;
267 	put_device(&ac97->dev);
268 }
269 EXPORT_SYMBOL_GPL(snd_soc_free_ac97_component);
270 
271 static struct snd_ac97_reset_cfg snd_ac97_rst_cfg;
272 
273 static void snd_soc_ac97_warm_reset(struct snd_ac97 *ac97)
274 {
275 	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
276 
277 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_warm_reset);
278 
279 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 1);
280 
281 	udelay(10);
282 
283 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
284 
285 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
286 	msleep(2);
287 }
288 
289 static void snd_soc_ac97_reset(struct snd_ac97 *ac97)
290 {
291 	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
292 
293 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_reset);
294 
295 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
296 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sdata, 0);
297 	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 0);
298 
299 	udelay(10);
300 
301 	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 1);
302 
303 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
304 	msleep(2);
305 }
306 
307 static int snd_soc_ac97_parse_pinctl(struct device *dev,
308 		struct snd_ac97_reset_cfg *cfg)
309 {
310 	struct pinctrl *p;
311 	struct pinctrl_state *state;
312 	int gpio;
313 	int ret;
314 
315 	p = devm_pinctrl_get(dev);
316 	if (IS_ERR(p)) {
317 		dev_err(dev, "Failed to get pinctrl\n");
318 		return PTR_ERR(p);
319 	}
320 	cfg->pctl = p;
321 
322 	state = pinctrl_lookup_state(p, "ac97-reset");
323 	if (IS_ERR(state)) {
324 		dev_err(dev, "Can't find pinctrl state ac97-reset\n");
325 		return PTR_ERR(state);
326 	}
327 	cfg->pstate_reset = state;
328 
329 	state = pinctrl_lookup_state(p, "ac97-warm-reset");
330 	if (IS_ERR(state)) {
331 		dev_err(dev, "Can't find pinctrl state ac97-warm-reset\n");
332 		return PTR_ERR(state);
333 	}
334 	cfg->pstate_warm_reset = state;
335 
336 	state = pinctrl_lookup_state(p, "ac97-running");
337 	if (IS_ERR(state)) {
338 		dev_err(dev, "Can't find pinctrl state ac97-running\n");
339 		return PTR_ERR(state);
340 	}
341 	cfg->pstate_run = state;
342 
343 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 0);
344 	if (gpio < 0) {
345 		dev_err(dev, "Can't find ac97-sync gpio\n");
346 		return gpio;
347 	}
348 	ret = devm_gpio_request(dev, gpio, "AC97 link sync");
349 	if (ret) {
350 		dev_err(dev, "Failed requesting ac97-sync gpio\n");
351 		return ret;
352 	}
353 	cfg->gpio_sync = gpio;
354 
355 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 1);
356 	if (gpio < 0) {
357 		dev_err(dev, "Can't find ac97-sdata gpio %d\n", gpio);
358 		return gpio;
359 	}
360 	ret = devm_gpio_request(dev, gpio, "AC97 link sdata");
361 	if (ret) {
362 		dev_err(dev, "Failed requesting ac97-sdata gpio\n");
363 		return ret;
364 	}
365 	cfg->gpio_sdata = gpio;
366 
367 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
368 	if (gpio < 0) {
369 		dev_err(dev, "Can't find ac97-reset gpio\n");
370 		return gpio;
371 	}
372 	ret = devm_gpio_request(dev, gpio, "AC97 link reset");
373 	if (ret) {
374 		dev_err(dev, "Failed requesting ac97-reset gpio\n");
375 		return ret;
376 	}
377 	cfg->gpio_reset = gpio;
378 
379 	return 0;
380 }
381 
382 struct snd_ac97_bus_ops *soc_ac97_ops;
383 EXPORT_SYMBOL_GPL(soc_ac97_ops);
384 
385 int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops)
386 {
387 	if (ops == soc_ac97_ops)
388 		return 0;
389 
390 	if (soc_ac97_ops && ops)
391 		return -EBUSY;
392 
393 	soc_ac97_ops = ops;
394 	soc_ac97_bus.ops = ops;
395 
396 	return 0;
397 }
398 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops);
399 
400 /**
401  * snd_soc_set_ac97_ops_of_reset - Set ac97 ops with generic ac97 reset functions
402  *
403  * This function sets the reset and warm_reset properties of ops and parses
404  * the device node of pdev to get pinctrl states and gpio numbers to use.
405  */
406 int snd_soc_set_ac97_ops_of_reset(struct snd_ac97_bus_ops *ops,
407 		struct platform_device *pdev)
408 {
409 	struct device *dev = &pdev->dev;
410 	struct snd_ac97_reset_cfg cfg;
411 	int ret;
412 
413 	ret = snd_soc_ac97_parse_pinctl(dev, &cfg);
414 	if (ret)
415 		return ret;
416 
417 	ret = snd_soc_set_ac97_ops(ops);
418 	if (ret)
419 		return ret;
420 
421 	ops->warm_reset = snd_soc_ac97_warm_reset;
422 	ops->reset = snd_soc_ac97_reset;
423 
424 	snd_ac97_rst_cfg = cfg;
425 	return 0;
426 }
427 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops_of_reset);
428