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_single_ended(struct gpio_chip *chip,
 107                                         unsigned int offset,
 108                                         enum single_ended_mode mode)
 109 {
 110         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
 111         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 112
 113         switch (mode) {
 114         case LINE_MODE_OPEN_DRAIN:
 115                 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
 116                                        WM8994_GPN_OP_CFG_MASK,
 117                                        WM8994_GPN_OP_CFG);
 118         case LINE_MODE_PUSH_PULL:
 119                 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
 120                                        WM8994_GPN_OP_CFG_MASK, 0);
 121         default:
 122                 break;
 123         }
 124
 125         return -ENOTSUPP;
 126 }
 127
 128 static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 129 {
 130         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
 131         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 132
 133         return regmap_irq_get_virq(wm8994->irq_data, offset);
 134 }
 135
 136
 137 #ifdef CONFIG_DEBUG_FS
 138 static const char *wm8994_gpio_fn(u16 fn)
 139 {
 140         switch (fn) {
 141         case WM8994_GP_FN_PIN_SPECIFIC:
 142                 return "pin-specific";
 143         case WM8994_GP_FN_GPIO:
 144                 return "GPIO";
 145         case WM8994_GP_FN_SDOUT:
 146                 return "SDOUT";
 147         case WM8994_GP_FN_IRQ:
 148                 return "IRQ";
 149         case WM8994_GP_FN_TEMPERATURE:
 150                 return "Temperature";
 151         case WM8994_GP_FN_MICBIAS1_DET:
 152                 return "MICBIAS1 detect";
 153         case WM8994_GP_FN_MICBIAS1_SHORT:
 154                 return "MICBIAS1 short";
 155         case WM8994_GP_FN_MICBIAS2_DET:
 156                 return "MICBIAS2 detect";
 157         case WM8994_GP_FN_MICBIAS2_SHORT:
 158                 return "MICBIAS2 short";
 159         case WM8994_GP_FN_FLL1_LOCK:
 160                 return "FLL1 lock";
 161         case WM8994_GP_FN_FLL2_LOCK:
 162                 return "FLL2 lock";
 163         case WM8994_GP_FN_SRC1_LOCK:
 164                 return "SRC1 lock";
 165         case WM8994_GP_FN_SRC2_LOCK:
 166                 return "SRC2 lock";
 167         case WM8994_GP_FN_DRC1_ACT:
 168                 return "DRC1 activity";
 169         case WM8994_GP_FN_DRC2_ACT:
 170                 return "DRC2 activity";
 171         case WM8994_GP_FN_DRC3_ACT:
 172                 return "DRC3 activity";
 173         case WM8994_GP_FN_WSEQ_STATUS:
 174                 return "Write sequencer";
 175         case WM8994_GP_FN_FIFO_ERROR:
 176                 return "FIFO error";
 177         case WM8994_GP_FN_OPCLK:
 178                 return "OPCLK";
 179         case WM8994_GP_FN_THW:
 180                 return "Thermal warning";
 181         case WM8994_GP_FN_DCS_DONE:
 182                 return "DC servo";
 183         case WM8994_GP_FN_FLL1_OUT:
 184                 return "FLL1 output";
 185         case WM8994_GP_FN_FLL2_OUT:
 186                 return "FLL1 output";
 187         default:
 188                 return "Unknown";
 189         }
 190 }
 191
 192 static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 193 {
 194         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
 195         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 196         int i;
 197
 198         for (i = 0; i < chip->ngpio; i++) {
 199                 int gpio = i + chip->base;
 200                 int reg;
 201                 const char *label;
 202
 203                 /* We report the GPIO even if it's not requested since
 204                  * we're also reporting things like alternate
 205                  * functions which apply even when the GPIO is not in
 206                  * use as a GPIO.
 207                  */
 208                 label = gpiochip_is_requested(chip, i);
 209                 if (!label)
 210                         label = "Unrequested";
 211
 212                 seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
 213
 214                 reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
 215                 if (reg < 0) {
 216                         dev_err(wm8994->dev,
 217                                 "GPIO control %d read failed: %d\n",
 218                                 gpio, reg);
 219                         seq_printf(s, "\n");
 220                         continue;
 221                 }
 222
 223                 if (reg & WM8994_GPN_DIR)
 224                         seq_printf(s, "in ");
 225                 else
 226                         seq_printf(s, "out ");
 227
 228                 if (reg & WM8994_GPN_PU)
 229                         seq_printf(s, "pull up ");
 230
 231                 if (reg & WM8994_GPN_PD)
 232                         seq_printf(s, "pull down ");
 233
 234                 if (reg & WM8994_GPN_POL)
 235                         seq_printf(s, "inverted ");
 236                 else
 237                         seq_printf(s, "noninverted ");
 238
 239                 if (reg & WM8994_GPN_OP_CFG)
 240                         seq_printf(s, "open drain ");
 241                 else
 242                         seq_printf(s, "push-pull ");
 243
 244                 seq_printf(s, "%s (%x)\n",
 245                            wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg);
 246         }
 247 }
 248 #else
 249 #define wm8994_gpio_dbg_show NULL
 250 #endif
 251
 252 static const struct gpio_chip template_chip = {
 253         .label                  = "wm8994",
 254         .owner                  = THIS_MODULE,
 255         .request                = wm8994_gpio_request,
 256         .direction_input        = wm8994_gpio_direction_in,
 257         .get                    = wm8994_gpio_get,
 258         .direction_output       = wm8994_gpio_direction_out,
 259         .set                    = wm8994_gpio_set,
 260         .set_single_ended       = wm8994_gpio_set_single_ended,
 261         .to_irq                 = wm8994_gpio_to_irq,
 262         .dbg_show               = wm8994_gpio_dbg_show,
 263         .can_sleep              = true,
 264 };
 265
 266 static int wm8994_gpio_probe(struct platform_device *pdev)
 267 {
 268         struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
 269         struct wm8994_pdata *pdata = dev_get_platdata(wm8994->dev);
 270         struct wm8994_gpio *wm8994_gpio;
 271         int ret;
 272
 273         wm8994_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8994_gpio),
 274                                    GFP_KERNEL);
 275         if (wm8994_gpio == NULL)
 276                 return -ENOMEM;
 277
 278         wm8994_gpio->wm8994 = wm8994;
 279         wm8994_gpio->gpio_chip = template_chip;
 280         wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
 281         wm8994_gpio->gpio_chip.parent = &pdev->dev;
 282         if (pdata && pdata->gpio_base)
 283                 wm8994_gpio->gpio_chip.base = pdata->gpio_base;
 284         else
 285                 wm8994_gpio->gpio_chip.base = -1;
 286
 287         ret = devm_gpiochip_add_data(&pdev->dev, &wm8994_gpio->gpio_chip,
 288                                      wm8994_gpio);
 289         if (ret < 0) {
 290                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
 291                         ret);
 292                 return ret;
 293         }
 294
 295         platform_set_drvdata(pdev, wm8994_gpio);
 296
 297         return ret;
 298 }
 299
 300 static struct platform_driver wm8994_gpio_driver = {
 301         .driver.name    = "wm8994-gpio",
 302         .probe          = wm8994_gpio_probe,
 303 };
 304
 305 static int __init wm8994_gpio_init(void)
 306 {
 307         return platform_driver_register(&wm8994_gpio_driver);
 308 }
 309 subsys_initcall(wm8994_gpio_init);
 310
 311 static void __exit wm8994_gpio_exit(void)
 312 {
 313         platform_driver_unregister(&wm8994_gpio_driver);
 314 }
 315 module_exit(wm8994_gpio_exit);
 316
 317 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 318 MODULE_DESCRIPTION("GPIO interface for WM8994");
 319 MODULE_LICENSE("GPL");
 320 MODULE_ALIAS("platform:wm8994-gpio");