sound/soc/soc-ac97.c

   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_codec *codec;
  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_codec *gpio_to_codec(struct gpio_chip *chip)
  61 {
  62         struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
  63
  64         return gpio_priv->codec;
  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_codec *codec = gpio_to_codec(chip);
  79
  80         dev_dbg(codec->dev, "set gpio %d to output\n", offset);
  81         return snd_soc_update_bits(codec, 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_codec *codec = gpio_to_codec(chip);
  88         int ret;
  89
  90         ret = snd_soc_read(codec, AC97_GPIO_STATUS);
  91         dev_dbg(codec->dev, "get gpio %d : %d\n", offset,
  92                 ret < 0 ? ret : ret & (1 << offset));
  93
  94         return ret < 0 ? ret : !!(ret & (1 << offset));
  95 }
  96
  97 static void snd_soc_ac97_gpio_set(struct gpio_chip *chip, unsigned offset,
  98                                   int value)
  99 {
 100         struct snd_ac97_gpio_priv *gpio_priv = gpiochip_get_data(chip);
 101         struct snd_soc_codec *codec = gpio_to_codec(chip);
 102
 103         gpio_priv->gpios_set &= ~(1 << offset);
 104         gpio_priv->gpios_set |= (!!value) << offset;
 105         snd_soc_write(codec, AC97_GPIO_STATUS, gpio_priv->gpios_set);
 106         dev_dbg(codec->dev, "set gpio %d to %d\n", offset, !!value);
 107 }
 108
 109 static int snd_soc_ac97_gpio_direction_out(struct gpio_chip *chip,
 110                                      unsigned offset, int value)
 111 {
 112         struct snd_soc_codec *codec = gpio_to_codec(chip);
 113
 114         dev_dbg(codec->dev, "set gpio %d to output\n", offset);
 115         snd_soc_ac97_gpio_set(chip, offset, value);
 116         return snd_soc_update_bits(codec, AC97_GPIO_CFG, 1 << offset, 0);
 117 }
 118
 119 static const struct gpio_chip snd_soc_ac97_gpio_chip = {
 120         .label                  = "snd_soc_ac97",
 121         .owner                  = THIS_MODULE,
 122         .request                = snd_soc_ac97_gpio_request,
 123         .direction_input        = snd_soc_ac97_gpio_direction_in,
 124         .get                    = snd_soc_ac97_gpio_get,
 125         .direction_output       = snd_soc_ac97_gpio_direction_out,
 126         .set                    = snd_soc_ac97_gpio_set,
 127         .can_sleep              = 1,
 128 };
 129
 130 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
 131                                   struct snd_soc_codec *codec)
 132 {
 133         struct snd_ac97_gpio_priv *gpio_priv;
 134         int ret;
 135
 136         gpio_priv = devm_kzalloc(codec->dev, sizeof(*gpio_priv), GFP_KERNEL);
 137         if (!gpio_priv)
 138                 return -ENOMEM;
 139         ac97->gpio_priv = gpio_priv;
 140         gpio_priv->codec = codec;
 141         gpio_priv->gpio_chip = snd_soc_ac97_gpio_chip;
 142         gpio_priv->gpio_chip.ngpio = AC97_NUM_GPIOS;
 143         gpio_priv->gpio_chip.parent = codec->dev;
 144         gpio_priv->gpio_chip.base = -1;
 145
 146         ret = gpiochip_add_data(&gpio_priv->gpio_chip, gpio_priv);
 147         if (ret != 0)
 148                 dev_err(codec->dev, "Failed to add GPIOs: %d\n", ret);
 149         return ret;
 150 }
 151
 152 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
 153 {
 154         gpiochip_remove(&ac97->gpio_priv->gpio_chip);
 155 }
 156 #else
 157 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97,
 158                                   struct snd_soc_codec *codec)
 159 {
 160         return 0;
 161 }
 162
 163 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97)
 164 {
 165 }
 166 #endif
 167
 168 /**
 169  * snd_soc_alloc_ac97_codec() - Allocate new a AC'97 device
 170  * @codec: The CODEC for which to create the AC'97 device
 171  *
 172  * Allocated a new snd_ac97 device and intializes it, but does not yet register
 173  * it. The caller is responsible to either call device_add(&ac97->dev) to
 174  * register the device, or to call put_device(&ac97->dev) to free the device.
 175  *
 176  * Returns: A snd_ac97 device or a PTR_ERR in case of an error.
 177  */
 178 struct snd_ac97 *snd_soc_alloc_ac97_codec(struct snd_soc_codec *codec)
 179 {
 180         struct snd_ac97 *ac97;
 181
 182         ac97 = kzalloc(sizeof(struct snd_ac97), GFP_KERNEL);
 183         if (ac97 == NULL)
 184                 return ERR_PTR(-ENOMEM);
 185
 186         ac97->bus = &soc_ac97_bus;
 187         ac97->num = 0;
 188
 189         ac97->dev.bus = &ac97_bus_type;
 190         ac97->dev.parent = codec->component.card->dev;
 191         ac97->dev.release = soc_ac97_device_release;
 192
 193         dev_set_name(&ac97->dev, "%d-%d:%s",
 194                      codec->component.card->snd_card->number, 0,
 195                      codec->component.name);
 196
 197         device_initialize(&ac97->dev);
 198
 199         return ac97;
 200 }
 201 EXPORT_SYMBOL(snd_soc_alloc_ac97_codec);
 202
 203 /**
 204  * snd_soc_new_ac97_codec - initailise AC97 device
 205  * @codec: audio codec
 206  * @id: The expected device ID
 207  * @id_mask: Mask that is applied to the device ID before comparing with @id
 208  *
 209  * Initialises AC97 codec resources for use by ad-hoc devices only.
 210  *
 211  * If @id is not 0 this function will reset the device, then read the ID from
 212  * the device and check if it matches the expected ID. If it doesn't match an
 213  * error will be returned and device will not be registered.
 214  *
 215  * Returns: A PTR_ERR() on failure or a valid snd_ac97 struct on success.
 216  */
 217 struct snd_ac97 *snd_soc_new_ac97_codec(struct snd_soc_codec *codec,
 218         unsigned int id, unsigned int id_mask)
 219 {
 220         struct snd_ac97 *ac97;
 221         int ret;
 222
 223         ac97 = snd_soc_alloc_ac97_codec(codec);
 224         if (IS_ERR(ac97))
 225                 return ac97;
 226
 227         if (id) {
 228                 ret = snd_ac97_reset(ac97, false, id, id_mask);
 229                 if (ret < 0) {
 230                         dev_err(codec->dev, "Failed to reset AC97 device: %d\n",
 231                                 ret);
 232                         goto err_put_device;
 233                 }
 234         }
 235
 236         ret = device_add(&ac97->dev);
 237         if (ret)
 238                 goto err_put_device;
 239
 240         ret = snd_soc_ac97_init_gpio(ac97, codec);
 241         if (ret)
 242                 goto err_put_device;
 243
 244         return ac97;
 245
 246 err_put_device:
 247         put_device(&ac97->dev);
 248         return ERR_PTR(ret);
 249 }
 250 EXPORT_SYMBOL_GPL(snd_soc_new_ac97_codec);
 251
 252 /**
 253  * snd_soc_free_ac97_codec - free AC97 codec device
 254  * @ac97: snd_ac97 device to be freed
 255  *
 256  * Frees AC97 codec device resources.
 257  */
 258 void snd_soc_free_ac97_codec(struct snd_ac97 *ac97)
 259 {
 260         snd_soc_ac97_free_gpio(ac97);
 261         device_del(&ac97->dev);
 262         ac97->bus = NULL;
 263         put_device(&ac97->dev);
 264 }
 265 EXPORT_SYMBOL_GPL(snd_soc_free_ac97_codec);
 266
 267 static struct snd_ac97_reset_cfg snd_ac97_rst_cfg;
 268
 269 static void snd_soc_ac97_warm_reset(struct snd_ac97 *ac97)
 270 {
 271         struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
 272
 273         pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_warm_reset);
 274
 275         gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 1);
 276
 277         udelay(10);
 278
 279         gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
 280
 281         pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
 282         msleep(2);
 283 }
 284
 285 static void snd_soc_ac97_reset(struct snd_ac97 *ac97)
 286 {
 287         struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
 288
 289         pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_reset);
 290
 291         gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
 292         gpio_direction_output(snd_ac97_rst_cfg.gpio_sdata, 0);
 293         gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 0);
 294
 295         udelay(10);
 296
 297         gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 1);
 298
 299         pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
 300         msleep(2);
 301 }
 302
 303 static int snd_soc_ac97_parse_pinctl(struct device *dev,
 304                 struct snd_ac97_reset_cfg *cfg)
 305 {
 306         struct pinctrl *p;
 307         struct pinctrl_state *state;
 308         int gpio;
 309         int ret;
 310
 311         p = devm_pinctrl_get(dev);
 312         if (IS_ERR(p)) {
 313                 dev_err(dev, "Failed to get pinctrl\n");
 314                 return PTR_ERR(p);
 315         }
 316         cfg->pctl = p;
 317
 318         state = pinctrl_lookup_state(p, "ac97-reset");
 319         if (IS_ERR(state)) {
 320                 dev_err(dev, "Can't find pinctrl state ac97-reset\n");
 321                 return PTR_ERR(state);
 322         }
 323         cfg->pstate_reset = state;
 324
 325         state = pinctrl_lookup_state(p, "ac97-warm-reset");
 326         if (IS_ERR(state)) {
 327                 dev_err(dev, "Can't find pinctrl state ac97-warm-reset\n");
 328                 return PTR_ERR(state);
 329         }
 330         cfg->pstate_warm_reset = state;
 331
 332         state = pinctrl_lookup_state(p, "ac97-running");
 333         if (IS_ERR(state)) {
 334                 dev_err(dev, "Can't find pinctrl state ac97-running\n");
 335                 return PTR_ERR(state);
 336         }
 337         cfg->pstate_run = state;
 338
 339         gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 0);
 340         if (gpio < 0) {
 341                 dev_err(dev, "Can't find ac97-sync gpio\n");
 342                 return gpio;
 343         }
 344         ret = devm_gpio_request(dev, gpio, "AC97 link sync");
 345         if (ret) {
 346                 dev_err(dev, "Failed requesting ac97-sync gpio\n");
 347                 return ret;
 348         }
 349         cfg->gpio_sync = gpio;
 350
 351         gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 1);
 352         if (gpio < 0) {
 353                 dev_err(dev, "Can't find ac97-sdata gpio %d\n", gpio);
 354                 return gpio;
 355         }
 356         ret = devm_gpio_request(dev, gpio, "AC97 link sdata");
 357         if (ret) {
 358                 dev_err(dev, "Failed requesting ac97-sdata gpio\n");
 359                 return ret;
 360         }
 361         cfg->gpio_sdata = gpio;
 362
 363         gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
 364         if (gpio < 0) {
 365                 dev_err(dev, "Can't find ac97-reset gpio\n");
 366                 return gpio;
 367         }
 368         ret = devm_gpio_request(dev, gpio, "AC97 link reset");
 369         if (ret) {
 370                 dev_err(dev, "Failed requesting ac97-reset gpio\n");
 371                 return ret;
 372         }
 373         cfg->gpio_reset = gpio;
 374
 375         return 0;
 376 }
 377
 378 struct snd_ac97_bus_ops *soc_ac97_ops;
 379 EXPORT_SYMBOL_GPL(soc_ac97_ops);
 380
 381 int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops)
 382 {
 383         if (ops == soc_ac97_ops)
 384                 return 0;
 385
 386         if (soc_ac97_ops && ops)
 387                 return -EBUSY;
 388
 389         soc_ac97_ops = ops;
 390         soc_ac97_bus.ops = ops;
 391
 392         return 0;
 393 }
 394 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops);
 395
 396 /**
 397  * snd_soc_set_ac97_ops_of_reset - Set ac97 ops with generic ac97 reset functions
 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);