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/init.h>
  24 #include <linux/of_gpio.h>
  25 #include <linux/of.h>
  26 #include <linux/pinctrl/consumer.h>
  27 #include <linux/slab.h>
  28 #include <sound/ac97_codec.h>
  29 #include <sound/soc.h>
  30
  31 struct snd_ac97_reset_cfg {
  32         struct pinctrl *pctl;
  33         struct pinctrl_state *pstate_reset;
  34         struct pinctrl_state *pstate_warm_reset;
  35         struct pinctrl_state *pstate_run;
  36         int gpio_sdata;
  37         int gpio_sync;
  38         int gpio_reset;
  39 };
  40
  41 static struct snd_ac97_bus soc_ac97_bus = {
  42         .ops = NULL, /* Gets initialized in snd_soc_set_ac97_ops() */
  43 };
  44
  45 static void soc_ac97_device_release(struct device *dev)
  46 {
  47         kfree(to_ac97_t(dev));
  48 }
  49
  50 /**
  51  * snd_soc_alloc_ac97_codec() - Allocate new a AC'97 device
  52  * @codec: The CODEC for which to create the AC'97 device
  53  *
  54  * Allocated a new snd_ac97 device and intializes it, but does not yet register
  55  * it. The caller is responsible to either call device_add(&ac97->dev) to
  56  * register the device, or to call put_device(&ac97->dev) to free the device.
  57  *
  58  * Returns: A snd_ac97 device or a PTR_ERR in case of an error.
  59  */
  60 struct snd_ac97 *snd_soc_alloc_ac97_codec(struct snd_soc_codec *codec)
  61 {
  62         struct snd_ac97 *ac97;
  63
  64         ac97 = kzalloc(sizeof(struct snd_ac97), GFP_KERNEL);
  65         if (ac97 == NULL)
  66                 return ERR_PTR(-ENOMEM);
  67
  68         ac97->bus = &soc_ac97_bus;
  69         ac97->num = 0;
  70
  71         ac97->dev.bus = &ac97_bus_type;
  72         ac97->dev.parent = codec->component.card->dev;
  73         ac97->dev.release = soc_ac97_device_release;
  74
  75         dev_set_name(&ac97->dev, "%d-%d:%s",
  76                      codec->component.card->snd_card->number, 0,
  77                      codec->component.name);
  78
  79         device_initialize(&ac97->dev);
  80
  81         return ac97;
  82 }
  83 EXPORT_SYMBOL(snd_soc_alloc_ac97_codec);
  84
  85 /**
  86  * snd_soc_new_ac97_codec - initailise AC97 device
  87  * @codec: audio codec
  88  * @id: The expected device ID
  89  * @id_mask: Mask that is applied to the device ID before comparing with @id
  90  *
  91  * Initialises AC97 codec resources for use by ad-hoc devices only.
  92  *
  93  * If @id is not 0 this function will reset the device, then read the ID from
  94  * the device and check if it matches the expected ID. If it doesn't match an
  95  * error will be returned and device will not be registered.
  96  *
  97  * Returns: A PTR_ERR() on failure or a valid snd_ac97 struct on success.
  98  */
  99 struct snd_ac97 *snd_soc_new_ac97_codec(struct snd_soc_codec *codec,
 100         unsigned int id, unsigned int id_mask)
 101 {
 102         struct snd_ac97 *ac97;
 103         int ret;
 104
 105         ac97 = snd_soc_alloc_ac97_codec(codec);
 106         if (IS_ERR(ac97))
 107                 return ac97;
 108
 109         if (id) {
 110                 ret = snd_ac97_reset(ac97, false, id, id_mask);
 111                 if (ret < 0) {
 112                         dev_err(codec->dev, "Failed to reset AC97 device: %d\n",
 113                                 ret);
 114                         goto err_put_device;
 115                 }
 116         }
 117
 118         ret = device_add(&ac97->dev);
 119         if (ret)
 120                 goto err_put_device;
 121
 122         return ac97;
 123
 124 err_put_device:
 125         put_device(&ac97->dev);
 126         return ERR_PTR(ret);
 127 }
 128 EXPORT_SYMBOL_GPL(snd_soc_new_ac97_codec);
 129
 130 /**
 131  * snd_soc_free_ac97_codec - free AC97 codec device
 132  * @codec: audio codec
 133  *
 134  * Frees AC97 codec device resources.
 135  */
 136 void snd_soc_free_ac97_codec(struct snd_ac97 *ac97)
 137 {
 138         device_del(&ac97->dev);
 139         ac97->bus = NULL;
 140         put_device(&ac97->dev);
 141 }
 142 EXPORT_SYMBOL_GPL(snd_soc_free_ac97_codec);
 143
 144 static struct snd_ac97_reset_cfg snd_ac97_rst_cfg;
 145
 146 static void snd_soc_ac97_warm_reset(struct snd_ac97 *ac97)
 147 {
 148         struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
 149
 150         pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_warm_reset);
 151
 152         gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 1);
 153
 154         udelay(10);
 155
 156         gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
 157
 158         pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
 159         msleep(2);
 160 }
 161
 162 static void snd_soc_ac97_reset(struct snd_ac97 *ac97)
 163 {
 164         struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
 165
 166         pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_reset);
 167
 168         gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
 169         gpio_direction_output(snd_ac97_rst_cfg.gpio_sdata, 0);
 170         gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 0);
 171
 172         udelay(10);
 173
 174         gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 1);
 175
 176         pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
 177         msleep(2);
 178 }
 179
 180 static int snd_soc_ac97_parse_pinctl(struct device *dev,
 181                 struct snd_ac97_reset_cfg *cfg)
 182 {
 183         struct pinctrl *p;
 184         struct pinctrl_state *state;
 185         int gpio;
 186         int ret;
 187
 188         p = devm_pinctrl_get(dev);
 189         if (IS_ERR(p)) {
 190                 dev_err(dev, "Failed to get pinctrl\n");
 191                 return PTR_ERR(p);
 192         }
 193         cfg->pctl = p;
 194
 195         state = pinctrl_lookup_state(p, "ac97-reset");
 196         if (IS_ERR(state)) {
 197                 dev_err(dev, "Can't find pinctrl state ac97-reset\n");
 198                 return PTR_ERR(state);
 199         }
 200         cfg->pstate_reset = state;
 201
 202         state = pinctrl_lookup_state(p, "ac97-warm-reset");
 203         if (IS_ERR(state)) {
 204                 dev_err(dev, "Can't find pinctrl state ac97-warm-reset\n");
 205                 return PTR_ERR(state);
 206         }
 207         cfg->pstate_warm_reset = state;
 208
 209         state = pinctrl_lookup_state(p, "ac97-running");
 210         if (IS_ERR(state)) {
 211                 dev_err(dev, "Can't find pinctrl state ac97-running\n");
 212                 return PTR_ERR(state);
 213         }
 214         cfg->pstate_run = state;
 215
 216         gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 0);
 217         if (gpio < 0) {
 218                 dev_err(dev, "Can't find ac97-sync gpio\n");
 219                 return gpio;
 220         }
 221         ret = devm_gpio_request(dev, gpio, "AC97 link sync");
 222         if (ret) {
 223                 dev_err(dev, "Failed requesting ac97-sync gpio\n");
 224                 return ret;
 225         }
 226         cfg->gpio_sync = gpio;
 227
 228         gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 1);
 229         if (gpio < 0) {
 230                 dev_err(dev, "Can't find ac97-sdata gpio %d\n", gpio);
 231                 return gpio;
 232         }
 233         ret = devm_gpio_request(dev, gpio, "AC97 link sdata");
 234         if (ret) {
 235                 dev_err(dev, "Failed requesting ac97-sdata gpio\n");
 236                 return ret;
 237         }
 238         cfg->gpio_sdata = gpio;
 239
 240         gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
 241         if (gpio < 0) {
 242                 dev_err(dev, "Can't find ac97-reset gpio\n");
 243                 return gpio;
 244         }
 245         ret = devm_gpio_request(dev, gpio, "AC97 link reset");
 246         if (ret) {
 247                 dev_err(dev, "Failed requesting ac97-reset gpio\n");
 248                 return ret;
 249         }
 250         cfg->gpio_reset = gpio;
 251
 252         return 0;
 253 }
 254
 255 struct snd_ac97_bus_ops *soc_ac97_ops;
 256 EXPORT_SYMBOL_GPL(soc_ac97_ops);
 257
 258 int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops)
 259 {
 260         if (ops == soc_ac97_ops)
 261                 return 0;
 262
 263         if (soc_ac97_ops && ops)
 264                 return -EBUSY;
 265
 266         soc_ac97_ops = ops;
 267         soc_ac97_bus.ops = ops;
 268
 269         return 0;
 270 }
 271 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops);
 272
 273 /**
 274  * snd_soc_set_ac97_ops_of_reset - Set ac97 ops with generic ac97 reset functions
 275  *
 276  * This function sets the reset and warm_reset properties of ops and parses
 277  * the device node of pdev to get pinctrl states and gpio numbers to use.
 278  */
 279 int snd_soc_set_ac97_ops_of_reset(struct snd_ac97_bus_ops *ops,
 280                 struct platform_device *pdev)
 281 {
 282         struct device *dev = &pdev->dev;
 283         struct snd_ac97_reset_cfg cfg;
 284         int ret;
 285
 286         ret = snd_soc_ac97_parse_pinctl(dev, &cfg);
 287         if (ret)
 288                 return ret;
 289
 290         ret = snd_soc_set_ac97_ops(ops);
 291         if (ret)
 292                 return ret;
 293
 294         ops->warm_reset = snd_soc_ac97_warm_reset;
 295         ops->reset = snd_soc_ac97_reset;
 296
 297         snd_ac97_rst_cfg = cfg;
 298         return 0;
 299 }
 300 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops_of_reset);