xref: /linux/sound/soc/soc-ac97.c (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
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 	ret = snd_soc_component_read(component, AC97_GPIO_STATUS);
86 
87 	dev_dbg(component->dev, "get gpio %d : %d\n", offset,
88 		ret & (1 << offset));
89 
90 	return !!(ret & (1 << offset));
91 }
92 
93 static void snd_soc_ac97_gpio_set(struct gpio_chip *chip, unsigned offset,
94 				  int value)
95 {
96 	struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
97 	struct snd_soc_component *component = gpio_to_component(chip);
98 
99 	gpio_priv->gpios_set &= ~(1 << offset);
100 	gpio_priv->gpios_set |= (!!value) << offset;
101 	snd_soc_component_write(component, AC97_GPIO_STATUS,
102 				gpio_priv->gpios_set);
103 	dev_dbg(component->dev, "set gpio %d to %d\n", offset, !!value);
104 }
105 
106 static int snd_soc_ac97_gpio_direction_out(struct gpio_chip *chip,
107 				     unsigned offset, int value)
108 {
109 	struct snd_soc_component *component = gpio_to_component(chip);
110 
111 	dev_dbg(component->dev, "set gpio %d to output\n", offset);
112 	snd_soc_ac97_gpio_set(chip, offset, value);
113 	return snd_soc_component_update_bits(component, AC97_GPIO_CFG,
114 					     1 << offset, 0);
115 }
116 
117 static const struct gpio_chip snd_soc_ac97_gpio_chip = {
118 	.label			= "snd_soc_ac97",
119 	.owner			= THIS_MODULE,
120 	.request		= snd_soc_ac97_gpio_request,
121 	.direction_input	= snd_soc_ac97_gpio_direction_in,
122 	.get			= snd_soc_ac97_gpio_get,
123 	.direction_output	= snd_soc_ac97_gpio_direction_out,
124 	.set			= snd_soc_ac97_gpio_set,
125 	.can_sleep		= 1,
126 };
127 
128 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
129 				  struct snd_soc_component *component)
130 {
131 	struct snd_ac97_gpio_priv *gpio_priv;
132 	int ret;
133 
134 	gpio_priv = devm_kzalloc(component->dev, sizeof(*gpio_priv), GFP_KERNEL);
135 	if (!gpio_priv)
136 		return -ENOMEM;
137 	ac97->gpio_priv = gpio_priv;
138 	gpio_priv->component = component;
139 	gpio_priv->gpio_chip = snd_soc_ac97_gpio_chip;
140 	gpio_priv->gpio_chip.ngpio = AC97_NUM_GPIOS;
141 	gpio_priv->gpio_chip.parent = component->dev;
142 	gpio_priv->gpio_chip.base = -1;
143 
144 	ret = gpiochip_add_data(&gpio_priv->gpio_chip, gpio_priv);
145 	if (ret != 0)
146 		dev_err(component->dev, "Failed to add GPIOs: %d\n", ret);
147 	return ret;
148 }
149 
150 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
151 {
152 	gpiochip_remove(&ac97->gpio_priv->gpio_chip);
153 }
154 #else
155 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
156 				  struct snd_soc_component *component)
157 {
158 	return 0;
159 }
160 
161 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
162 {
163 }
164 #endif
165 
166 /**
167  * snd_soc_alloc_ac97_component() - Allocate new a AC'97 device
168  * @component: The COMPONENT for which to create the AC'97 device
169  *
170  * Allocated a new snd_ac97 device and intializes it, but does not yet register
171  * it. The caller is responsible to either call device_add(&ac97->dev) to
172  * register the device, or to call put_device(&ac97->dev) to free the device.
173  *
174  * Returns: A snd_ac97 device or a PTR_ERR in case of an error.
175  */
176 struct snd_ac97 *snd_soc_alloc_ac97_component(struct snd_soc_component *component)
177 {
178 	struct snd_ac97 *ac97;
179 
180 	ac97 = kzalloc(sizeof(struct snd_ac97), GFP_KERNEL);
181 	if (ac97 == NULL)
182 		return ERR_PTR(-ENOMEM);
183 
184 	ac97->bus = &soc_ac97_bus;
185 	ac97->num = 0;
186 
187 	ac97->dev.bus = &ac97_bus_type;
188 	ac97->dev.parent = component->card->dev;
189 	ac97->dev.release = soc_ac97_device_release;
190 
191 	dev_set_name(&ac97->dev, "%d-%d:%s",
192 		     component->card->snd_card->number, 0,
193 		     component->name);
194 
195 	device_initialize(&ac97->dev);
196 
197 	return ac97;
198 }
199 EXPORT_SYMBOL(snd_soc_alloc_ac97_component);
200 
201 /**
202  * snd_soc_new_ac97_component - initailise AC97 device
203  * @component: audio component
204  * @id: The expected device ID
205  * @id_mask: Mask that is applied to the device ID before comparing with @id
206  *
207  * Initialises AC97 component resources for use by ad-hoc devices only.
208  *
209  * If @id is not 0 this function will reset the device, then read the ID from
210  * the device and check if it matches the expected ID. If it doesn't match an
211  * error will be returned and device will not be registered.
212  *
213  * Returns: A PTR_ERR() on failure or a valid snd_ac97 struct on success.
214  */
215 struct snd_ac97 *snd_soc_new_ac97_component(struct snd_soc_component *component,
216 	unsigned int id, unsigned int id_mask)
217 {
218 	struct snd_ac97 *ac97;
219 	int ret;
220 
221 	ac97 = snd_soc_alloc_ac97_component(component);
222 	if (IS_ERR(ac97))
223 		return ac97;
224 
225 	if (id) {
226 		ret = snd_ac97_reset(ac97, false, id, id_mask);
227 		if (ret < 0) {
228 			dev_err(component->dev, "Failed to reset AC97 device: %d\n",
229 				ret);
230 			goto err_put_device;
231 		}
232 	}
233 
234 	ret = device_add(&ac97->dev);
235 	if (ret)
236 		goto err_put_device;
237 
238 	ret = snd_soc_ac97_init_gpio(ac97, component);
239 	if (ret)
240 		goto err_put_device;
241 
242 	return ac97;
243 
244 err_put_device:
245 	put_device(&ac97->dev);
246 	return ERR_PTR(ret);
247 }
248 EXPORT_SYMBOL_GPL(snd_soc_new_ac97_component);
249 
250 /**
251  * snd_soc_free_ac97_component - free AC97 component device
252  * @ac97: snd_ac97 device to be freed
253  *
254  * Frees AC97 component device resources.
255  */
256 void snd_soc_free_ac97_component(struct snd_ac97 *ac97)
257 {
258 	snd_soc_ac97_free_gpio(ac97);
259 	device_del(&ac97->dev);
260 	ac97->bus = NULL;
261 	put_device(&ac97->dev);
262 }
263 EXPORT_SYMBOL_GPL(snd_soc_free_ac97_component);
264 
265 static struct snd_ac97_reset_cfg snd_ac97_rst_cfg;
266 
267 static void snd_soc_ac97_warm_reset(struct snd_ac97 *ac97)
268 {
269 	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
270 
271 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_warm_reset);
272 
273 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 1);
274 
275 	udelay(10);
276 
277 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
278 
279 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
280 	msleep(2);
281 }
282 
283 static void snd_soc_ac97_reset(struct snd_ac97 *ac97)
284 {
285 	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
286 
287 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_reset);
288 
289 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
290 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sdata, 0);
291 	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 0);
292 
293 	udelay(10);
294 
295 	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 1);
296 
297 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
298 	msleep(2);
299 }
300 
301 static int snd_soc_ac97_parse_pinctl(struct device *dev,
302 		struct snd_ac97_reset_cfg *cfg)
303 {
304 	struct pinctrl *p;
305 	struct pinctrl_state *state;
306 	int gpio;
307 	int ret;
308 
309 	p = devm_pinctrl_get(dev);
310 	if (IS_ERR(p)) {
311 		dev_err(dev, "Failed to get pinctrl\n");
312 		return PTR_ERR(p);
313 	}
314 	cfg->pctl = p;
315 
316 	state = pinctrl_lookup_state(p, "ac97-reset");
317 	if (IS_ERR(state)) {
318 		dev_err(dev, "Can't find pinctrl state ac97-reset\n");
319 		return PTR_ERR(state);
320 	}
321 	cfg->pstate_reset = state;
322 
323 	state = pinctrl_lookup_state(p, "ac97-warm-reset");
324 	if (IS_ERR(state)) {
325 		dev_err(dev, "Can't find pinctrl state ac97-warm-reset\n");
326 		return PTR_ERR(state);
327 	}
328 	cfg->pstate_warm_reset = state;
329 
330 	state = pinctrl_lookup_state(p, "ac97-running");
331 	if (IS_ERR(state)) {
332 		dev_err(dev, "Can't find pinctrl state ac97-running\n");
333 		return PTR_ERR(state);
334 	}
335 	cfg->pstate_run = state;
336 
337 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 0);
338 	if (gpio < 0) {
339 		dev_err(dev, "Can't find ac97-sync gpio\n");
340 		return gpio;
341 	}
342 	ret = devm_gpio_request(dev, gpio, "AC97 link sync");
343 	if (ret) {
344 		dev_err(dev, "Failed requesting ac97-sync gpio\n");
345 		return ret;
346 	}
347 	cfg->gpio_sync = gpio;
348 
349 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 1);
350 	if (gpio < 0) {
351 		dev_err(dev, "Can't find ac97-sdata gpio %d\n", gpio);
352 		return gpio;
353 	}
354 	ret = devm_gpio_request(dev, gpio, "AC97 link sdata");
355 	if (ret) {
356 		dev_err(dev, "Failed requesting ac97-sdata gpio\n");
357 		return ret;
358 	}
359 	cfg->gpio_sdata = gpio;
360 
361 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
362 	if (gpio < 0) {
363 		dev_err(dev, "Can't find ac97-reset gpio\n");
364 		return gpio;
365 	}
366 	ret = devm_gpio_request(dev, gpio, "AC97 link reset");
367 	if (ret) {
368 		dev_err(dev, "Failed requesting ac97-reset gpio\n");
369 		return ret;
370 	}
371 	cfg->gpio_reset = gpio;
372 
373 	return 0;
374 }
375 
376 struct snd_ac97_bus_ops *soc_ac97_ops;
377 EXPORT_SYMBOL_GPL(soc_ac97_ops);
378 
379 int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops)
380 {
381 	if (ops == soc_ac97_ops)
382 		return 0;
383 
384 	if (soc_ac97_ops && ops)
385 		return -EBUSY;
386 
387 	soc_ac97_ops = ops;
388 	soc_ac97_bus.ops = ops;
389 
390 	return 0;
391 }
392 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops);
393 
394 /**
395  * snd_soc_set_ac97_ops_of_reset - Set ac97 ops with generic ac97 reset functions
396  * @ops: bus ops
397  * @pdev: platform device
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