xref: /linux/sound/soc/soc-ac97.c (revision 818448e9cf92e5c6b3c10320372eefcbe4174e4f)
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 static struct snd_ac97_bus soc_ac97_bus = {
38 	.ops = NULL, /* Gets initialized in snd_soc_set_ac97_ops() */
39 };
40 
41 static void soc_ac97_device_release(struct device *dev)
42 {
43 	kfree(to_ac97_t(dev));
44 }
45 
46 #ifdef CONFIG_GPIOLIB
47 struct snd_ac97_gpio_priv {
48 	struct gpio_chip gpio_chip;
49 	unsigned int gpios_set;
50 	struct snd_soc_component *component;
51 };
52 
53 static inline struct snd_soc_component *gpio_to_component(struct gpio_chip *chip)
54 {
55 	struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
56 
57 	return gpio_priv->component;
58 }
59 
60 static int snd_soc_ac97_gpio_request(struct gpio_chip *chip, unsigned int offset)
61 {
62 	if (offset >= AC97_NUM_GPIOS)
63 		return -EINVAL;
64 
65 	return 0;
66 }
67 
68 static int snd_soc_ac97_gpio_direction_in(struct gpio_chip *chip,
69 					  unsigned int offset)
70 {
71 	struct snd_soc_component *component = gpio_to_component(chip);
72 
73 	dev_dbg(component->dev, "set gpio %d to output\n", offset);
74 	return snd_soc_component_update_bits(component, AC97_GPIO_CFG,
75 				   1 << offset, 1 << offset);
76 }
77 
78 static int snd_soc_ac97_gpio_get(struct gpio_chip *chip, unsigned int offset)
79 {
80 	struct snd_soc_component *component = gpio_to_component(chip);
81 	int ret;
82 
83 	ret = snd_soc_component_read(component, AC97_GPIO_STATUS);
84 
85 	dev_dbg(component->dev, "get gpio %d : %d\n", offset,
86 		ret & (1 << offset));
87 
88 	return !!(ret & (1 << offset));
89 }
90 
91 static void snd_soc_ac97_gpio_set(struct gpio_chip *chip, unsigned int offset,
92 				  int value)
93 {
94 	struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
95 	struct snd_soc_component *component = gpio_to_component(chip);
96 
97 	gpio_priv->gpios_set &= ~(1 << offset);
98 	gpio_priv->gpios_set |= (!!value) << offset;
99 	snd_soc_component_write(component, AC97_GPIO_STATUS,
100 				gpio_priv->gpios_set);
101 	dev_dbg(component->dev, "set gpio %d to %d\n", offset, !!value);
102 }
103 
104 static int snd_soc_ac97_gpio_direction_out(struct gpio_chip *chip,
105 				     unsigned offset, int value)
106 {
107 	struct snd_soc_component *component = gpio_to_component(chip);
108 
109 	dev_dbg(component->dev, "set gpio %d to output\n", offset);
110 	snd_soc_ac97_gpio_set(chip, offset, value);
111 	return snd_soc_component_update_bits(component, AC97_GPIO_CFG,
112 					     1 << offset, 0);
113 }
114 
115 static const struct gpio_chip snd_soc_ac97_gpio_chip = {
116 	.label			= "snd_soc_ac97",
117 	.owner			= THIS_MODULE,
118 	.request		= snd_soc_ac97_gpio_request,
119 	.direction_input	= snd_soc_ac97_gpio_direction_in,
120 	.get			= snd_soc_ac97_gpio_get,
121 	.direction_output	= snd_soc_ac97_gpio_direction_out,
122 	.set			= snd_soc_ac97_gpio_set,
123 	.can_sleep		= 1,
124 };
125 
126 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
127 				  struct snd_soc_component *component)
128 {
129 	struct snd_ac97_gpio_priv *gpio_priv;
130 	int ret;
131 
132 	gpio_priv = devm_kzalloc(component->dev, sizeof(*gpio_priv), GFP_KERNEL);
133 	if (!gpio_priv)
134 		return -ENOMEM;
135 	ac97->gpio_priv = gpio_priv;
136 	gpio_priv->component = component;
137 	gpio_priv->gpio_chip = snd_soc_ac97_gpio_chip;
138 	gpio_priv->gpio_chip.ngpio = AC97_NUM_GPIOS;
139 	gpio_priv->gpio_chip.parent = component->dev;
140 	gpio_priv->gpio_chip.base = -1;
141 
142 	ret = gpiochip_add_data(&gpio_priv->gpio_chip, gpio_priv);
143 	if (ret != 0)
144 		dev_err(component->dev, "Failed to add GPIOs: %d\n", ret);
145 	return ret;
146 }
147 
148 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
149 {
150 	gpiochip_remove(&ac97->gpio_priv->gpio_chip);
151 }
152 #else
153 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
154 				  struct snd_soc_component *component)
155 {
156 	return 0;
157 }
158 
159 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
160 {
161 }
162 #endif
163 
164 /**
165  * snd_soc_alloc_ac97_component() - Allocate new a AC'97 device
166  * @component: The COMPONENT for which to create the AC'97 device
167  *
168  * Allocated a new snd_ac97 device and intializes it, but does not yet register
169  * it. The caller is responsible to either call device_add(&ac97->dev) to
170  * register the device, or to call put_device(&ac97->dev) to free the device.
171  *
172  * Returns: A snd_ac97 device or a PTR_ERR in case of an error.
173  */
174 struct snd_ac97 *snd_soc_alloc_ac97_component(struct snd_soc_component *component)
175 {
176 	struct snd_ac97 *ac97;
177 
178 	ac97 = kzalloc(sizeof(struct snd_ac97), GFP_KERNEL);
179 	if (ac97 == NULL)
180 		return ERR_PTR(-ENOMEM);
181 
182 	ac97->bus = &soc_ac97_bus;
183 	ac97->num = 0;
184 
185 	ac97->dev.bus = &ac97_bus_type;
186 	ac97->dev.parent = component->card->dev;
187 	ac97->dev.release = soc_ac97_device_release;
188 
189 	dev_set_name(&ac97->dev, "%d-%d:%s",
190 		     component->card->snd_card->number, 0,
191 		     component->name);
192 
193 	device_initialize(&ac97->dev);
194 
195 	return ac97;
196 }
197 EXPORT_SYMBOL(snd_soc_alloc_ac97_component);
198 
199 /**
200  * snd_soc_new_ac97_component - initailise AC97 device
201  * @component: audio component
202  * @id: The expected device ID
203  * @id_mask: Mask that is applied to the device ID before comparing with @id
204  *
205  * Initialises AC97 component resources for use by ad-hoc devices only.
206  *
207  * If @id is not 0 this function will reset the device, then read the ID from
208  * the device and check if it matches the expected ID. If it doesn't match an
209  * error will be returned and device will not be registered.
210  *
211  * Returns: A PTR_ERR() on failure or a valid snd_ac97 struct on success.
212  */
213 struct snd_ac97 *snd_soc_new_ac97_component(struct snd_soc_component *component,
214 	unsigned int id, unsigned int id_mask)
215 {
216 	struct snd_ac97 *ac97;
217 	int ret;
218 
219 	ac97 = snd_soc_alloc_ac97_component(component);
220 	if (IS_ERR(ac97))
221 		return ac97;
222 
223 	if (id) {
224 		ret = snd_ac97_reset(ac97, false, id, id_mask);
225 		if (ret < 0) {
226 			dev_err(component->dev, "Failed to reset AC97 device: %d\n",
227 				ret);
228 			goto err_put_device;
229 		}
230 	}
231 
232 	ret = device_add(&ac97->dev);
233 	if (ret)
234 		goto err_put_device;
235 
236 	ret = snd_soc_ac97_init_gpio(ac97, component);
237 	if (ret)
238 		goto err_put_device;
239 
240 	return ac97;
241 
242 err_put_device:
243 	put_device(&ac97->dev);
244 	return ERR_PTR(ret);
245 }
246 EXPORT_SYMBOL_GPL(snd_soc_new_ac97_component);
247 
248 /**
249  * snd_soc_free_ac97_component - free AC97 component device
250  * @ac97: snd_ac97 device to be freed
251  *
252  * Frees AC97 component device resources.
253  */
254 void snd_soc_free_ac97_component(struct snd_ac97 *ac97)
255 {
256 	snd_soc_ac97_free_gpio(ac97);
257 	device_del(&ac97->dev);
258 	ac97->bus = NULL;
259 	put_device(&ac97->dev);
260 }
261 EXPORT_SYMBOL_GPL(snd_soc_free_ac97_component);
262 
263 static struct snd_ac97_reset_cfg snd_ac97_rst_cfg;
264 
265 static void snd_soc_ac97_warm_reset(struct snd_ac97 *ac97)
266 {
267 	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
268 
269 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_warm_reset);
270 
271 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 1);
272 
273 	udelay(10);
274 
275 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
276 
277 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
278 	msleep(2);
279 }
280 
281 static void snd_soc_ac97_reset(struct snd_ac97 *ac97)
282 {
283 	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
284 
285 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_reset);
286 
287 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
288 	gpio_direction_output(snd_ac97_rst_cfg.gpio_sdata, 0);
289 	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 0);
290 
291 	udelay(10);
292 
293 	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 1);
294 
295 	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
296 	msleep(2);
297 }
298 
299 static int snd_soc_ac97_parse_pinctl(struct device *dev,
300 		struct snd_ac97_reset_cfg *cfg)
301 {
302 	struct pinctrl *p;
303 	struct pinctrl_state *state;
304 	int gpio;
305 	int ret;
306 
307 	p = devm_pinctrl_get(dev);
308 	if (IS_ERR(p)) {
309 		dev_err(dev, "Failed to get pinctrl\n");
310 		return PTR_ERR(p);
311 	}
312 	cfg->pctl = p;
313 
314 	state = pinctrl_lookup_state(p, "ac97-reset");
315 	if (IS_ERR(state)) {
316 		dev_err(dev, "Can't find pinctrl state ac97-reset\n");
317 		return PTR_ERR(state);
318 	}
319 	cfg->pstate_reset = state;
320 
321 	state = pinctrl_lookup_state(p, "ac97-warm-reset");
322 	if (IS_ERR(state)) {
323 		dev_err(dev, "Can't find pinctrl state ac97-warm-reset\n");
324 		return PTR_ERR(state);
325 	}
326 	cfg->pstate_warm_reset = state;
327 
328 	state = pinctrl_lookup_state(p, "ac97-running");
329 	if (IS_ERR(state)) {
330 		dev_err(dev, "Can't find pinctrl state ac97-running\n");
331 		return PTR_ERR(state);
332 	}
333 	cfg->pstate_run = state;
334 
335 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 0);
336 	if (gpio < 0) {
337 		dev_err(dev, "Can't find ac97-sync gpio\n");
338 		return gpio;
339 	}
340 	ret = devm_gpio_request(dev, gpio, "AC97 link sync");
341 	if (ret) {
342 		dev_err(dev, "Failed requesting ac97-sync gpio\n");
343 		return ret;
344 	}
345 	cfg->gpio_sync = gpio;
346 
347 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 1);
348 	if (gpio < 0) {
349 		dev_err(dev, "Can't find ac97-sdata gpio %d\n", gpio);
350 		return gpio;
351 	}
352 	ret = devm_gpio_request(dev, gpio, "AC97 link sdata");
353 	if (ret) {
354 		dev_err(dev, "Failed requesting ac97-sdata gpio\n");
355 		return ret;
356 	}
357 	cfg->gpio_sdata = gpio;
358 
359 	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
360 	if (gpio < 0) {
361 		dev_err(dev, "Can't find ac97-reset gpio\n");
362 		return gpio;
363 	}
364 	ret = devm_gpio_request(dev, gpio, "AC97 link reset");
365 	if (ret) {
366 		dev_err(dev, "Failed requesting ac97-reset gpio\n");
367 		return ret;
368 	}
369 	cfg->gpio_reset = gpio;
370 
371 	return 0;
372 }
373 
374 struct snd_ac97_bus_ops *soc_ac97_ops;
375 EXPORT_SYMBOL_GPL(soc_ac97_ops);
376 
377 int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops)
378 {
379 	if (ops == soc_ac97_ops)
380 		return 0;
381 
382 	if (soc_ac97_ops && ops)
383 		return -EBUSY;
384 
385 	soc_ac97_ops = ops;
386 	soc_ac97_bus.ops = ops;
387 
388 	return 0;
389 }
390 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops);
391 
392 /**
393  * snd_soc_set_ac97_ops_of_reset - Set ac97 ops with generic ac97 reset functions
394  * @ops: bus ops
395  * @pdev: platform device
396  *
397  * This function sets the reset and warm_reset properties of ops and parses
398  * the device node of pdev to get pinctrl states and gpio numbers to use.
399  */
400 int snd_soc_set_ac97_ops_of_reset(struct snd_ac97_bus_ops *ops,
401 		struct platform_device *pdev)
402 {
403 	struct device *dev = &pdev->dev;
404 	struct snd_ac97_reset_cfg cfg;
405 	int ret;
406 
407 	ret = snd_soc_ac97_parse_pinctl(dev, &cfg);
408 	if (ret)
409 		return ret;
410 
411 	ret = snd_soc_set_ac97_ops(ops);
412 	if (ret)
413 		return ret;
414 
415 	ops->warm_reset = snd_soc_ac97_warm_reset;
416 	ops->reset = snd_soc_ac97_reset;
417 
418 	snd_ac97_rst_cfg = cfg;
419 	return 0;
420 }
421 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops_of_reset);
422