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 = 63 container_of(chip, struct snd_ac97_gpio_priv, gpio_chip); 64 65 return gpio_priv->codec; 66 } 67 68 static int snd_soc_ac97_gpio_request(struct gpio_chip *chip, unsigned offset) 69 { 70 if (offset >= AC97_NUM_GPIOS) 71 return -EINVAL; 72 73 return 0; 74 } 75 76 static int snd_soc_ac97_gpio_direction_in(struct gpio_chip *chip, 77 unsigned offset) 78 { 79 struct snd_soc_codec *codec = gpio_to_codec(chip); 80 81 dev_dbg(codec->dev, "set gpio %d to output\n", offset); 82 return snd_soc_update_bits(codec, AC97_GPIO_CFG, 83 1 << offset, 1 << offset); 84 } 85 86 static int snd_soc_ac97_gpio_get(struct gpio_chip *chip, unsigned offset) 87 { 88 struct snd_soc_codec *codec = gpio_to_codec(chip); 89 int ret; 90 91 ret = snd_soc_read(codec, AC97_GPIO_STATUS); 92 dev_dbg(codec->dev, "get gpio %d : %d\n", offset, 93 ret < 0 ? ret : ret & (1 << offset)); 94 95 return ret < 0 ? ret : !!(ret & (1 << offset)); 96 } 97 98 static void snd_soc_ac97_gpio_set(struct gpio_chip *chip, unsigned offset, 99 int value) 100 { 101 struct snd_ac97_gpio_priv *gpio_priv = 102 container_of(chip, struct snd_ac97_gpio_priv, gpio_chip); 103 struct snd_soc_codec *codec = gpio_to_codec(chip); 104 105 gpio_priv->gpios_set &= ~(1 << offset); 106 gpio_priv->gpios_set |= (!!value) << offset; 107 snd_soc_write(codec, AC97_GPIO_STATUS, gpio_priv->gpios_set); 108 dev_dbg(codec->dev, "set gpio %d to %d\n", offset, !!value); 109 } 110 111 static int snd_soc_ac97_gpio_direction_out(struct gpio_chip *chip, 112 unsigned offset, int value) 113 { 114 struct snd_soc_codec *codec = gpio_to_codec(chip); 115 116 dev_dbg(codec->dev, "set gpio %d to output\n", offset); 117 snd_soc_ac97_gpio_set(chip, offset, value); 118 return snd_soc_update_bits(codec, AC97_GPIO_CFG, 1 << offset, 0); 119 } 120 121 static struct gpio_chip snd_soc_ac97_gpio_chip = { 122 .label = "snd_soc_ac97", 123 .owner = THIS_MODULE, 124 .request = snd_soc_ac97_gpio_request, 125 .direction_input = snd_soc_ac97_gpio_direction_in, 126 .get = snd_soc_ac97_gpio_get, 127 .direction_output = snd_soc_ac97_gpio_direction_out, 128 .set = snd_soc_ac97_gpio_set, 129 .can_sleep = 1, 130 }; 131 132 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97, 133 struct snd_soc_codec *codec) 134 { 135 struct snd_ac97_gpio_priv *gpio_priv; 136 int ret; 137 138 gpio_priv = devm_kzalloc(codec->dev, sizeof(*gpio_priv), GFP_KERNEL); 139 if (!gpio_priv) 140 return -ENOMEM; 141 ac97->gpio_priv = gpio_priv; 142 gpio_priv->codec = codec; 143 gpio_priv->gpio_chip = snd_soc_ac97_gpio_chip; 144 gpio_priv->gpio_chip.ngpio = AC97_NUM_GPIOS; 145 gpio_priv->gpio_chip.parent = codec->dev; 146 gpio_priv->gpio_chip.base = -1; 147 148 ret = gpiochip_add(&gpio_priv->gpio_chip); 149 if (ret != 0) 150 dev_err(codec->dev, "Failed to add GPIOs: %d\n", ret); 151 return ret; 152 } 153 154 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97) 155 { 156 gpiochip_remove(&ac97->gpio_priv->gpio_chip); 157 } 158 #else 159 static int snd_soc_ac97_init_gpio(struct snd_ac97 *ac97, 160 struct snd_soc_codec *codec) 161 { 162 return 0; 163 } 164 165 static void snd_soc_ac97_free_gpio(struct snd_ac97 *ac97) 166 { 167 } 168 #endif 169 170 /** 171 * snd_soc_alloc_ac97_codec() - Allocate new a AC'97 device 172 * @codec: The CODEC for which to create the AC'97 device 173 * 174 * Allocated a new snd_ac97 device and intializes it, but does not yet register 175 * it. The caller is responsible to either call device_add(&ac97->dev) to 176 * register the device, or to call put_device(&ac97->dev) to free the device. 177 * 178 * Returns: A snd_ac97 device or a PTR_ERR in case of an error. 179 */ 180 struct snd_ac97 *snd_soc_alloc_ac97_codec(struct snd_soc_codec *codec) 181 { 182 struct snd_ac97 *ac97; 183 184 ac97 = kzalloc(sizeof(struct snd_ac97), GFP_KERNEL); 185 if (ac97 == NULL) 186 return ERR_PTR(-ENOMEM); 187 188 ac97->bus = &soc_ac97_bus; 189 ac97->num = 0; 190 191 ac97->dev.bus = &ac97_bus_type; 192 ac97->dev.parent = codec->component.card->dev; 193 ac97->dev.release = soc_ac97_device_release; 194 195 dev_set_name(&ac97->dev, "%d-%d:%s", 196 codec->component.card->snd_card->number, 0, 197 codec->component.name); 198 199 device_initialize(&ac97->dev); 200 201 return ac97; 202 } 203 EXPORT_SYMBOL(snd_soc_alloc_ac97_codec); 204 205 /** 206 * snd_soc_new_ac97_codec - initailise AC97 device 207 * @codec: audio codec 208 * @id: The expected device ID 209 * @id_mask: Mask that is applied to the device ID before comparing with @id 210 * 211 * Initialises AC97 codec resources for use by ad-hoc devices only. 212 * 213 * If @id is not 0 this function will reset the device, then read the ID from 214 * the device and check if it matches the expected ID. If it doesn't match an 215 * error will be returned and device will not be registered. 216 * 217 * Returns: A PTR_ERR() on failure or a valid snd_ac97 struct on success. 218 */ 219 struct snd_ac97 *snd_soc_new_ac97_codec(struct snd_soc_codec *codec, 220 unsigned int id, unsigned int id_mask) 221 { 222 struct snd_ac97 *ac97; 223 int ret; 224 225 ac97 = snd_soc_alloc_ac97_codec(codec); 226 if (IS_ERR(ac97)) 227 return ac97; 228 229 if (id) { 230 ret = snd_ac97_reset(ac97, false, id, id_mask); 231 if (ret < 0) { 232 dev_err(codec->dev, "Failed to reset AC97 device: %d\n", 233 ret); 234 goto err_put_device; 235 } 236 } 237 238 ret = device_add(&ac97->dev); 239 if (ret) 240 goto err_put_device; 241 242 ret = snd_soc_ac97_init_gpio(ac97, codec); 243 if (ret) 244 goto err_put_device; 245 246 return ac97; 247 248 err_put_device: 249 put_device(&ac97->dev); 250 return ERR_PTR(ret); 251 } 252 EXPORT_SYMBOL_GPL(snd_soc_new_ac97_codec); 253 254 /** 255 * snd_soc_free_ac97_codec - free AC97 codec device 256 * @codec: audio codec 257 * 258 * Frees AC97 codec device resources. 259 */ 260 void snd_soc_free_ac97_codec(struct snd_ac97 *ac97) 261 { 262 snd_soc_ac97_free_gpio(ac97); 263 device_del(&ac97->dev); 264 ac97->bus = NULL; 265 put_device(&ac97->dev); 266 } 267 EXPORT_SYMBOL_GPL(snd_soc_free_ac97_codec); 268 269 static struct snd_ac97_reset_cfg snd_ac97_rst_cfg; 270 271 static void snd_soc_ac97_warm_reset(struct snd_ac97 *ac97) 272 { 273 struct pinctrl *pctl = snd_ac97_rst_cfg.pctl; 274 275 pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_warm_reset); 276 277 gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 1); 278 279 udelay(10); 280 281 gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0); 282 283 pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run); 284 msleep(2); 285 } 286 287 static void snd_soc_ac97_reset(struct snd_ac97 *ac97) 288 { 289 struct pinctrl *pctl = snd_ac97_rst_cfg.pctl; 290 291 pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_reset); 292 293 gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0); 294 gpio_direction_output(snd_ac97_rst_cfg.gpio_sdata, 0); 295 gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 0); 296 297 udelay(10); 298 299 gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 1); 300 301 pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run); 302 msleep(2); 303 } 304 305 static int snd_soc_ac97_parse_pinctl(struct device *dev, 306 struct snd_ac97_reset_cfg *cfg) 307 { 308 struct pinctrl *p; 309 struct pinctrl_state *state; 310 int gpio; 311 int ret; 312 313 p = devm_pinctrl_get(dev); 314 if (IS_ERR(p)) { 315 dev_err(dev, "Failed to get pinctrl\n"); 316 return PTR_ERR(p); 317 } 318 cfg->pctl = p; 319 320 state = pinctrl_lookup_state(p, "ac97-reset"); 321 if (IS_ERR(state)) { 322 dev_err(dev, "Can't find pinctrl state ac97-reset\n"); 323 return PTR_ERR(state); 324 } 325 cfg->pstate_reset = state; 326 327 state = pinctrl_lookup_state(p, "ac97-warm-reset"); 328 if (IS_ERR(state)) { 329 dev_err(dev, "Can't find pinctrl state ac97-warm-reset\n"); 330 return PTR_ERR(state); 331 } 332 cfg->pstate_warm_reset = state; 333 334 state = pinctrl_lookup_state(p, "ac97-running"); 335 if (IS_ERR(state)) { 336 dev_err(dev, "Can't find pinctrl state ac97-running\n"); 337 return PTR_ERR(state); 338 } 339 cfg->pstate_run = state; 340 341 gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 0); 342 if (gpio < 0) { 343 dev_err(dev, "Can't find ac97-sync gpio\n"); 344 return gpio; 345 } 346 ret = devm_gpio_request(dev, gpio, "AC97 link sync"); 347 if (ret) { 348 dev_err(dev, "Failed requesting ac97-sync gpio\n"); 349 return ret; 350 } 351 cfg->gpio_sync = gpio; 352 353 gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 1); 354 if (gpio < 0) { 355 dev_err(dev, "Can't find ac97-sdata gpio %d\n", gpio); 356 return gpio; 357 } 358 ret = devm_gpio_request(dev, gpio, "AC97 link sdata"); 359 if (ret) { 360 dev_err(dev, "Failed requesting ac97-sdata gpio\n"); 361 return ret; 362 } 363 cfg->gpio_sdata = gpio; 364 365 gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 2); 366 if (gpio < 0) { 367 dev_err(dev, "Can't find ac97-reset gpio\n"); 368 return gpio; 369 } 370 ret = devm_gpio_request(dev, gpio, "AC97 link reset"); 371 if (ret) { 372 dev_err(dev, "Failed requesting ac97-reset gpio\n"); 373 return ret; 374 } 375 cfg->gpio_reset = gpio; 376 377 return 0; 378 } 379 380 struct snd_ac97_bus_ops *soc_ac97_ops; 381 EXPORT_SYMBOL_GPL(soc_ac97_ops); 382 383 int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops) 384 { 385 if (ops == soc_ac97_ops) 386 return 0; 387 388 if (soc_ac97_ops && ops) 389 return -EBUSY; 390 391 soc_ac97_ops = ops; 392 soc_ac97_bus.ops = ops; 393 394 return 0; 395 } 396 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops); 397 398 /** 399 * snd_soc_set_ac97_ops_of_reset - Set ac97 ops with generic ac97 reset functions 400 * 401 * This function sets the reset and warm_reset properties of ops and parses 402 * the device node of pdev to get pinctrl states and gpio numbers to use. 403 */ 404 int snd_soc_set_ac97_ops_of_reset(struct snd_ac97_bus_ops *ops, 405 struct platform_device *pdev) 406 { 407 struct device *dev = &pdev->dev; 408 struct snd_ac97_reset_cfg cfg; 409 int ret; 410 411 ret = snd_soc_ac97_parse_pinctl(dev, &cfg); 412 if (ret) 413 return ret; 414 415 ret = snd_soc_set_ac97_ops(ops); 416 if (ret) 417 return ret; 418 419 ops->warm_reset = snd_soc_ac97_warm_reset; 420 ops->reset = snd_soc_ac97_reset; 421 422 snd_ac97_rst_cfg = cfg; 423 return 0; 424 } 425 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops_of_reset); 426