drivers/gpio/gpio-wm8994.c

   1 /*
   2  * gpiolib support for Wolfson WM8994
   3  *
   4  * Copyright 2009 Wolfson Microelectronics PLC.
   5  *
   6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7  *
   8  *  This program is free software; you can redistribute  it and/or modify it
   9  *  under  the terms of  the GNU General  Public License as published by the
  10  *  Free Software Foundation;  either version 2 of the  License, or (at your
  11  *  option) any later version.
  12  *
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/slab.h>
  17 #include <linux/module.h>
  18 #include <linux/gpio.h>
  19 #include <linux/mfd/core.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/seq_file.h>
  22 #include <linux/regmap.h>
  23
  24 #include <linux/mfd/wm8994/core.h>
  25 #include <linux/mfd/wm8994/pdata.h>
  26 #include <linux/mfd/wm8994/gpio.h>
  27 #include <linux/mfd/wm8994/registers.h>
  28
  29 struct wm8994_gpio {
  30         struct wm8994 *wm8994;
  31         struct gpio_chip gpio_chip;
  32 };
  33
  34 static int wm8994_gpio_request(struct gpio_chip *chip, unsigned offset)
  35 {
  36         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
  37         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  38
  39         switch (wm8994->type) {
  40         case WM8958:
  41                 switch (offset) {
  42                 case 1:
  43                 case 2:
  44                 case 3:
  45                 case 4:
  46                 case 6:
  47                         return -EINVAL;
  48                 }
  49                 break;
  50         default:
  51                 break;
  52         }
  53
  54         return 0;
  55 }
  56
  57 static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
  58 {
  59         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
  60         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  61
  62         return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
  63                                WM8994_GPN_DIR, WM8994_GPN_DIR);
  64 }
  65
  66 static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset)
  67 {
  68         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
  69         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  70         int ret;
  71
  72         ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset);
  73         if (ret < 0)
  74                 return ret;
  75
  76         if (ret & WM8994_GPN_LVL)
  77                 return 1;
  78         else
  79                 return 0;
  80 }
  81
  82 static int wm8994_gpio_direction_out(struct gpio_chip *chip,
  83                                      unsigned offset, int value)
  84 {
  85         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
  86         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  87
  88         if (value)
  89                 value = WM8994_GPN_LVL;
  90
  91         return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
  92                                WM8994_GPN_DIR | WM8994_GPN_LVL, value);
  93 }
  94
  95 static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
  96 {
  97         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
  98         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  99
 100         if (value)
 101                 value = WM8994_GPN_LVL;
 102
 103         wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value);
 104 }
 105
 106 static int wm8994_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
 107                                   unsigned long config)
 108 {
 109         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
 110         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 111
 112         switch (pinconf_to_config_param(config)) {
 113         case PIN_CONFIG_DRIVE_OPEN_DRAIN:
 114                 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
 115                                        WM8994_GPN_OP_CFG_MASK,
 116                                        WM8994_GPN_OP_CFG);
 117         case PIN_CONFIG_DRIVE_PUSH_PULL:
 118                 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
 119                                        WM8994_GPN_OP_CFG_MASK, 0);
 120         default:
 121                 break;
 122         }
 123
 124         return -ENOTSUPP;
 125 }
 126
 127 static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 128 {
 129         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
 130         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 131
 132         return regmap_irq_get_virq(wm8994->irq_data, offset);
 133 }
 134
 135
 136 #ifdef CONFIG_DEBUG_FS
 137 static const char *wm8994_gpio_fn(u16 fn)
 138 {
 139         switch (fn) {
 140         case WM8994_GP_FN_PIN_SPECIFIC:
 141                 return "pin-specific";
 142         case WM8994_GP_FN_GPIO:
 143                 return "GPIO";
 144         case WM8994_GP_FN_SDOUT:
 145                 return "SDOUT";
 146         case WM8994_GP_FN_IRQ:
 147                 return "IRQ";
 148         case WM8994_GP_FN_TEMPERATURE:
 149                 return "Temperature";
 150         case WM8994_GP_FN_MICBIAS1_DET:
 151                 return "MICBIAS1 detect";
 152         case WM8994_GP_FN_MICBIAS1_SHORT:
 153                 return "MICBIAS1 short";
 154         case WM8994_GP_FN_MICBIAS2_DET:
 155                 return "MICBIAS2 detect";
 156         case WM8994_GP_FN_MICBIAS2_SHORT:
 157                 return "MICBIAS2 short";
 158         case WM8994_GP_FN_FLL1_LOCK:
 159                 return "FLL1 lock";
 160         case WM8994_GP_FN_FLL2_LOCK:
 161                 return "FLL2 lock";
 162         case WM8994_GP_FN_SRC1_LOCK:
 163                 return "SRC1 lock";
 164         case WM8994_GP_FN_SRC2_LOCK:
 165                 return "SRC2 lock";
 166         case WM8994_GP_FN_DRC1_ACT:
 167                 return "DRC1 activity";
 168         case WM8994_GP_FN_DRC2_ACT:
 169                 return "DRC2 activity";
 170         case WM8994_GP_FN_DRC3_ACT:
 171                 return "DRC3 activity";
 172         case WM8994_GP_FN_WSEQ_STATUS:
 173                 return "Write sequencer";
 174         case WM8994_GP_FN_FIFO_ERROR:
 175                 return "FIFO error";
 176         case WM8994_GP_FN_OPCLK:
 177                 return "OPCLK";
 178         case WM8994_GP_FN_THW:
 179                 return "Thermal warning";
 180         case WM8994_GP_FN_DCS_DONE:
 181                 return "DC servo";
 182         case WM8994_GP_FN_FLL1_OUT:
 183                 return "FLL1 output";
 184         case WM8994_GP_FN_FLL2_OUT:
 185                 return "FLL1 output";
 186         default:
 187                 return "Unknown";
 188         }
 189 }
 190
 191 static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 192 {
 193         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
 194         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 195         int i;
 196
 197         for (i = 0; i < chip->ngpio; i++) {
 198                 int gpio = i + chip->base;
 199                 int reg;
 200                 const char *label;
 201
 202                 /* We report the GPIO even if it's not requested since
 203                  * we're also reporting things like alternate
 204                  * functions which apply even when the GPIO is not in
 205                  * use as a GPIO.
 206                  */
 207                 label = gpiochip_is_requested(chip, i);
 208                 if (!label)
 209                         label = "Unrequested";
 210
 211                 seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
 212
 213                 reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
 214                 if (reg < 0) {
 215                         dev_err(wm8994->dev,
 216                                 "GPIO control %d read failed: %d\n",
 217                                 gpio, reg);
 218                         seq_printf(s, "\n");
 219                         continue;
 220                 }
 221
 222                 if (reg & WM8994_GPN_DIR)
 223                         seq_printf(s, "in ");
 224                 else
 225                         seq_printf(s, "out ");
 226
 227                 if (reg & WM8994_GPN_PU)
 228                         seq_printf(s, "pull up ");
 229
 230                 if (reg & WM8994_GPN_PD)
 231                         seq_printf(s, "pull down ");
 232
 233                 if (reg & WM8994_GPN_POL)
 234                         seq_printf(s, "inverted ");
 235                 else
 236                         seq_printf(s, "noninverted ");
 237
 238                 if (reg & WM8994_GPN_OP_CFG)
 239                         seq_printf(s, "open drain ");
 240                 else
 241                         seq_printf(s, "push-pull ");
 242
 243                 seq_printf(s, "%s (%x)\n",
 244                            wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg);
 245         }
 246 }
 247 #else
 248 #define wm8994_gpio_dbg_show NULL
 249 #endif
 250
 251 static const struct gpio_chip template_chip = {
 252         .label                  = "wm8994",
 253         .owner                  = THIS_MODULE,
 254         .request                = wm8994_gpio_request,
 255         .direction_input        = wm8994_gpio_direction_in,
 256         .get                    = wm8994_gpio_get,
 257         .direction_output       = wm8994_gpio_direction_out,
 258         .set                    = wm8994_gpio_set,
 259         .set_config             = wm8994_gpio_set_config,
 260         .to_irq                 = wm8994_gpio_to_irq,
 261         .dbg_show               = wm8994_gpio_dbg_show,
 262         .can_sleep              = true,
 263 };
 264
 265 static int wm8994_gpio_probe(struct platform_device *pdev)
 266 {
 267         struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
 268         struct wm8994_pdata *pdata = dev_get_platdata(wm8994->dev);
 269         struct wm8994_gpio *wm8994_gpio;
 270         int ret;
 271
 272         wm8994_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8994_gpio),
 273                                    GFP_KERNEL);
 274         if (wm8994_gpio == NULL)
 275                 return -ENOMEM;
 276
 277         wm8994_gpio->wm8994 = wm8994;
 278         wm8994_gpio->gpio_chip = template_chip;
 279         wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
 280         wm8994_gpio->gpio_chip.parent = &pdev->dev;
 281         if (pdata && pdata->gpio_base)
 282                 wm8994_gpio->gpio_chip.base = pdata->gpio_base;
 283         else
 284                 wm8994_gpio->gpio_chip.base = -1;
 285
 286         ret = devm_gpiochip_add_data(&pdev->dev, &wm8994_gpio->gpio_chip,
 287                                      wm8994_gpio);
 288         if (ret < 0) {
 289                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
 290                         ret);
 291                 return ret;
 292         }
 293
 294         platform_set_drvdata(pdev, wm8994_gpio);
 295
 296         return ret;
 297 }
 298
 299 static struct platform_driver wm8994_gpio_driver = {
 300         .driver.name    = "wm8994-gpio",
 301         .probe          = wm8994_gpio_probe,
 302 };
 303
 304 static int __init wm8994_gpio_init(void)
 305 {
 306         return platform_driver_register(&wm8994_gpio_driver);
 307 }
 308 subsys_initcall(wm8994_gpio_init);
 309
 310 static void __exit wm8994_gpio_exit(void)
 311 {
 312         platform_driver_unregister(&wm8994_gpio_driver);
 313 }
 314 module_exit(wm8994_gpio_exit);
 315
 316 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 317 MODULE_DESCRIPTION("GPIO interface for WM8994");
 318 MODULE_LICENSE("GPL");
 319 MODULE_ALIAS("platform:wm8994-gpio");