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