xref: /openbmc/linux/sound/soc/soc-ac97.c (revision ebd09753)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // soc-ac97.c  --  ALSA SoC Audio Layer AC97 support
4 //
5 // Copyright 2005 Wolfson Microelectronics PLC.
6 // Copyright 2005 Openedhand Ltd.
7 // Copyright (C) 2010 Slimlogic Ltd.
8 // Copyright (C) 2010 Texas Instruments Inc.
9 //
10 // Author: Liam Girdwood <lrg@slimlogic.co.uk>
11 //         with code, comments and ideas from :-
12 //         Richard Purdie <richard@openedhand.com>
13 
14 #include <linux/ctype.h>
15 #include <linux/delay.h>
16 #include <linux/export.h>
17 #include <linux/gpio.h>
18 #include <linux/gpio/driver.h>
19 #include <linux/init.h>
20 #include <linux/of_gpio.h>
21 #include <linux/of.h>
22 #include <linux/pinctrl/consumer.h>
23 #include <linux/slab.h>
24 #include <sound/ac97_codec.h>
25 #include <sound/soc.h>
26 
27 struct snd_ac97_reset_cfg {
28 	struct pinctrl *pctl;
29 	struct pinctrl_state *pstate_reset;
30 	struct pinctrl_state *pstate_warm_reset;
31 	struct pinctrl_state *pstate_run;
32 	int gpio_sdata;
33 	int gpio_sync;
34 	int gpio_reset;
35 };
36 
37 struct snd_ac97_gpio_priv {
38 #ifdef CONFIG_GPIOLIB
39 	struct gpio_chip gpio_chip;
40 #endif
41 	unsigned int gpios_set;
42 	struct snd_soc_component *component;
43 };
44 
45 static struct snd_ac97_bus soc_ac97_bus = {
46 	.ops = NULL, /* Gets initialized in snd_soc_set_ac97_ops() */
47 };
48 
49 static void soc_ac97_device_release(struct device *dev)
50 {
51 	kfree(to_ac97_t(dev));
52 }
53 
54 #ifdef CONFIG_GPIOLIB
55 static inline struct snd_soc_component *gpio_to_component(struct gpio_chip *chip)
56 {
57 	struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
58 
59 	return gpio_priv->component;
60 }
61 
62 static int snd_soc_ac97_gpio_request(struct gpio_chip *chip, unsigned offset)
63 {
64 	if (offset >= AC97_NUM_GPIOS)
65 		return -EINVAL;
66 
67 	return 0;
68 }
69 
70 static int snd_soc_ac97_gpio_direction_in(struct gpio_chip *chip,
71 					  unsigned offset)
72 {
73 	struct snd_soc_component *component = gpio_to_component(chip);
74 
75 	dev_dbg(component->dev, "set gpio %d to output\n", offset);
76 	return snd_soc_component_update_bits(component, AC97_GPIO_CFG,
77 				   1 << offset, 1 << offset);
78 }
79 
80 static int snd_soc_ac97_gpio_get(struct gpio_chip *chip, unsigned offset)
81 {
82 	struct snd_soc_component *component = gpio_to_component(chip);
83 	int ret;
84 
85 	if (snd_soc_component_read(component, AC97_GPIO_STATUS, &ret) < 0)
86 		ret = -1;
87 
88 	dev_dbg(component->dev, "get gpio %d : %d\n", offset,
89 		ret < 0 ? ret : ret & (1 << offset));
90 
91 	return ret < 0 ? ret : !!(ret & (1 << offset));
92 }
93 
94 static void snd_soc_ac97_gpio_set(struct gpio_chip *chip, unsigned offset,
95 				  int value)
96 {
97 	struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
98 	struct snd_soc_component *component = gpio_to_component(chip);
99 
100 	gpio_priv->gpios_set &= ~(1 << offset);
101 	gpio_priv->gpios_set |= (!!value) << offset;
102 	snd_soc_component_write(component, AC97_GPIO_STATUS,
103 				gpio_priv->gpios_set);
104 	dev_dbg(component->dev, "set gpio %d to %d\n", offset, !!value);
105 }
106 
107 static int snd_soc_ac97_gpio_direction_out(struct gpio_chip *chip,
108 				     unsigned offset, int value)
109 {
110 	struct snd_soc_component *component = gpio_to_component(chip);
111 
112 	dev_dbg(component->dev, "set gpio %d to output\n", offset);
113 	snd_soc_ac97_gpio_set(chip, offset, value);
114 	return snd_soc_component_update_bits(component, AC97_GPIO_CFG,
115 					     1 << offset, 0);
116 }
117 
118 static const struct gpio_chip snd_soc_ac97_gpio_chip = {
119 	.label			= "snd_soc_ac97",
120 	.owner			= THIS_MODULE,
121 	.request		= snd_soc_ac97_gpio_request,
122 	.direction_input	= snd_soc_ac97_gpio_direction_in,
123 	.get			= snd_soc_ac97_gpio_get,
124 	.direction_output	= snd_soc_ac97_gpio_direction_out,
125 	.set			= snd_soc_ac97_gpio_set,
126 	.can_sleep		= 1,
127 };
128 
129 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
130 				  struct snd_soc_component *component)
131 {
132 	struct snd_ac97_gpio_priv *gpio_priv;
133 	int ret;
134 
135 	gpio_priv = devm_kzalloc(component->dev, sizeof(*gpio_priv), GFP_KERNEL);
136 	if (!gpio_priv)
137 		return -ENOMEM;
138 	ac97->gpio_priv = gpio_priv;
139 	gpio_priv->component = component;
140 	gpio_priv->gpio_chip = snd_soc_ac97_gpio_chip;
141 	gpio_priv->gpio_chip.ngpio = AC97_NUM_GPIOS;
142 	gpio_priv->gpio_chip.parent = component->dev;
143 	gpio_priv->gpio_chip.base = -1;
144 
145 	ret = gpiochip_add_data(&gpio_priv->gpio_chip, gpio_priv);
146 	if (ret != 0)
147 		dev_err(component->dev, "Failed to add GPIOs: %d\n", ret);
148 	return ret;
149 }
150 
151 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
152 {
153 	gpiochip_remove(&ac97->gpio_priv->gpio_chip);
154 }
155 #else
156 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
157 				  struct snd_soc_component *component)
158 {
159 	return 0;
160 }
161 
162 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
163 {
164 }
165 #endif
166 
167 /**
168  * snd_soc_alloc_ac97_component() - Allocate new a AC'97 device
169  * @component: The COMPONENT for which to create the AC'97 device
170  *
171  * Allocated a new snd_ac97 device and intializes it, but does not yet register
172  * it. The caller is responsible to either call device_add(&ac97->dev) to
173  * register the device, or to call put_device(&ac97->dev) to free the device.
174  *
175  * Returns: A snd_ac97 device or a PTR_ERR in case of an error.
176  */
177 struct snd_ac97 *snd_soc_alloc_ac97_component(struct snd_soc_component *component)
178 {
179 	struct snd_ac97 *ac97;
180 
181 	ac97 = kzalloc(sizeof(struct snd_ac97), GFP_KERNEL);
182 	if (ac97 == NULL)
183 		return ERR_PTR(-ENOMEM);
184 
185 	ac97->bus = &soc_ac97_bus;
186 	ac97->num = 0;
187 
188 	ac97->dev.bus = &ac97_bus_type;
189 	ac97->dev.parent = component->card->dev;
190 	ac97->dev.release = soc_ac97_device_release;
191 
192 	dev_set_name(&ac97->dev, "%d-%d:%s",
193 		     component->card->snd_card->number, 0,
194 		     component->name);
195 
196 	device_initialize(&ac97->dev);
197 
198 	return ac97;
199 }
200 EXPORT_SYMBOL(snd_soc_alloc_ac97_component);
201 
202 /**
203  * snd_soc_new_ac97_component - initailise AC97 device
204  * @component: audio component
205  * @id: The expected device ID
206  * @id_mask: Mask that is applied to the device ID before comparing with @id
207  *
208  * Initialises AC97 component resources for use by ad-hoc devices only.
209  *
210  * If @id is not 0 this function will reset the device, then read the ID from
211  * the device and check if it matches the expected ID. If it doesn't match an
212  * error will be returned and device will not be registered.
213  *
214  * Returns: A PTR_ERR() on failure or a valid snd_ac97 struct on success.
215  */
216 struct snd_ac97 *snd_soc_new_ac97_component(struct snd_soc_component *component,
217 	unsigned int id, unsigned int id_mask)
218 {
219 	struct snd_ac97 *ac97;
220 	int ret;
221 
222 	ac97 = snd_soc_alloc_ac97_component(component);
223 	if (IS_ERR(ac97))
224 		return ac97;
225 
226 	if (id) {
227 		ret = snd_ac97_reset(ac97, false, id, id_mask);
228 		if (ret < 0) {
229 			dev_err(component->dev, "Failed to reset AC97 device: %d\n",
230 				ret);
231 			goto err_put_device;
232 		}
233 	}
234 
235 	ret = device_add(&ac97->dev);
236 	if (ret)
237 		goto err_put_device;
238 
239 	ret = snd_soc_ac97_init_gpio(ac97, component);
240 	if (ret)
241 		goto err_put_device;
242 
243 	return ac97;
244 
245 err_put_device:
246 	put_device(&ac97->dev);
247 	return ERR_PTR(ret);
248 }
249 EXPORT_SYMBOL_GPL(snd_soc_new_ac97_component);
250 
251 /**
252  * snd_soc_free_ac97_component - free AC97 component device
253  * @ac97: snd_ac97 device to be freed
254  *
255  * Frees AC97 component device resources.
256  */
257 void snd_soc_free_ac97_component(struct snd_ac97 *ac97)
258 {
259 	snd_soc_ac97_free_gpio(ac97);
260 	device_del(&ac97->dev);
261 	ac97->bus = NULL;
262 	put_device(&ac97->dev);
263 }
264 EXPORT_SYMBOL_GPL(snd_soc_free_ac97_component);
265 
266 static struct snd_ac97_reset_cfg snd_ac97_rst_cfg;
267 
268 static void snd_soc_ac97_warm_reset(struct snd_ac97 *ac97)
269 {
270 	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
271 
272 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_warm_reset);
273 
274 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 1);
275 
276 	udelay(10);
277 
278 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
279 
280 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
281 	msleep(2);
282 }
283 
284 static void snd_soc_ac97_reset(struct snd_ac97 *ac97)
285 {
286 	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
287 
288 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_reset);
289 
290 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
291 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sdata, 0);
292 	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 0);
293 
294 	udelay(10);
295 
296 	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 1);
297 
298 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
299 	msleep(2);
300 }
301 
302 static int snd_soc_ac97_parse_pinctl(struct device *dev,
303 		struct snd_ac97_reset_cfg *cfg)
304 {
305 	struct pinctrl *p;
306 	struct pinctrl_state *state;
307 	int gpio;
308 	int ret;
309 
310 	p = devm_pinctrl_get(dev);
311 	if (IS_ERR(p)) {
312 		dev_err(dev, "Failed to get pinctrl\n");
313 		return PTR_ERR(p);
314 	}
315 	cfg->pctl = p;
316 
317 	state = pinctrl_lookup_state(p, "ac97-reset");
318 	if (IS_ERR(state)) {
319 		dev_err(dev, "Can't find pinctrl state ac97-reset\n");
320 		return PTR_ERR(state);
321 	}
322 	cfg->pstate_reset = state;
323 
324 	state = pinctrl_lookup_state(p, "ac97-warm-reset");
325 	if (IS_ERR(state)) {
326 		dev_err(dev, "Can't find pinctrl state ac97-warm-reset\n");
327 		return PTR_ERR(state);
328 	}
329 	cfg->pstate_warm_reset = state;
330 
331 	state = pinctrl_lookup_state(p, "ac97-running");
332 	if (IS_ERR(state)) {
333 		dev_err(dev, "Can't find pinctrl state ac97-running\n");
334 		return PTR_ERR(state);
335 	}
336 	cfg->pstate_run = state;
337 
338 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 0);
339 	if (gpio < 0) {
340 		dev_err(dev, "Can't find ac97-sync gpio\n");
341 		return gpio;
342 	}
343 	ret = devm_gpio_request(dev, gpio, "AC97 link sync");
344 	if (ret) {
345 		dev_err(dev, "Failed requesting ac97-sync gpio\n");
346 		return ret;
347 	}
348 	cfg->gpio_sync = gpio;
349 
350 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 1);
351 	if (gpio < 0) {
352 		dev_err(dev, "Can't find ac97-sdata gpio %d\n", gpio);
353 		return gpio;
354 	}
355 	ret = devm_gpio_request(dev, gpio, "AC97 link sdata");
356 	if (ret) {
357 		dev_err(dev, "Failed requesting ac97-sdata gpio\n");
358 		return ret;
359 	}
360 	cfg->gpio_sdata = gpio;
361 
362 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
363 	if (gpio < 0) {
364 		dev_err(dev, "Can't find ac97-reset gpio\n");
365 		return gpio;
366 	}
367 	ret = devm_gpio_request(dev, gpio, "AC97 link reset");
368 	if (ret) {
369 		dev_err(dev, "Failed requesting ac97-reset gpio\n");
370 		return ret;
371 	}
372 	cfg->gpio_reset = gpio;
373 
374 	return 0;
375 }
376 
377 struct snd_ac97_bus_ops *soc_ac97_ops;
378 EXPORT_SYMBOL_GPL(soc_ac97_ops);
379 
380 int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops)
381 {
382 	if (ops == soc_ac97_ops)
383 		return 0;
384 
385 	if (soc_ac97_ops && ops)
386 		return -EBUSY;
387 
388 	soc_ac97_ops = ops;
389 	soc_ac97_bus.ops = ops;
390 
391 	return 0;
392 }
393 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops);
394 
395 /**
396  * snd_soc_set_ac97_ops_of_reset - Set ac97 ops with generic ac97 reset functions
397  *
398  * This function sets the reset and warm_reset properties of ops and parses
399  * the device node of pdev to get pinctrl states and gpio numbers to use.
400  */
401 int snd_soc_set_ac97_ops_of_reset(struct snd_ac97_bus_ops *ops,
402 		struct platform_device *pdev)
403 {
404 	struct device *dev = &pdev->dev;
405 	struct snd_ac97_reset_cfg cfg;
406 	int ret;
407 
408 	ret = snd_soc_ac97_parse_pinctl(dev, &cfg);
409 	if (ret)
410 		return ret;
411 
412 	ret = snd_soc_set_ac97_ops(ops);
413 	if (ret)
414 		return ret;
415 
416 	ops->warm_reset = snd_soc_ac97_warm_reset;
417 	ops->reset = snd_soc_ac97_reset;
418 
419 	snd_ac97_rst_cfg = cfg;
420 	return 0;
421 }
422 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops_of_reset);
423