Pileus Git - ~andy/linux/blob - 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
  23 #include <linux/mfd/wm8994/core.h>
  24 #include <linux/mfd/wm8994/pdata.h>
  25 #include <linux/mfd/wm8994/gpio.h>
  26 #include <linux/mfd/wm8994/registers.h>
  27
  28 struct wm8994_gpio {
  29         struct wm8994 *wm8994;
  30         struct gpio_chip gpio_chip;
  31 };
  32
  33 static inline struct wm8994_gpio *to_wm8994_gpio(struct gpio_chip *chip)
  34 {
  35         return container_of(chip, struct wm8994_gpio, gpio_chip);
  36 }
  37
  38 static int wm8994_gpio_request(struct gpio_chip *chip, unsigned offset)
  39 {
  40         struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
  41         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  42
  43         switch (wm8994->type) {
  44         case WM8958:
  45                 switch (offset) {
  46                 case 1:
  47                 case 2:
  48                 case 3:
  49                 case 4:
  50                 case 6:
  51                         return -EINVAL;
  52                 }
  53                 break;
  54         default:
  55                 break;
  56         }
  57
  58         return 0;
  59 }
  60
  61 static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
  62 {
  63         struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
  64         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  65
  66         return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
  67                                WM8994_GPN_DIR, WM8994_GPN_DIR);
  68 }
  69
  70 static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset)
  71 {
  72         struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
  73         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  74         int ret;
  75
  76         ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset);
  77         if (ret < 0)
  78                 return ret;
  79
  80         if (ret & WM8994_GPN_LVL)
  81                 return 1;
  82         else
  83                 return 0;
  84 }
  85
  86 static int wm8994_gpio_direction_out(struct gpio_chip *chip,
  87                                      unsigned offset, int value)
  88 {
  89         struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
  90         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  91
  92         if (value)
  93                 value = WM8994_GPN_LVL;
  94
  95         return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
  96                                WM8994_GPN_DIR | WM8994_GPN_LVL, value);
  97 }
  98
  99 static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 100 {
 101         struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
 102         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 103
 104         if (value)
 105                 value = WM8994_GPN_LVL;
 106
 107         wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value);
 108 }
 109
 110 static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 111 {
 112         struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
 113         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 114
 115         if (!wm8994->irq_base)
 116                 return -EINVAL;
 117
 118         return wm8994->irq_base + offset;
 119 }
 120
 121
 122 #ifdef CONFIG_DEBUG_FS
 123 static const char *wm8994_gpio_fn(u16 fn)
 124 {
 125         switch (fn) {
 126         case WM8994_GP_FN_PIN_SPECIFIC:
 127                 return "pin-specific";
 128         case WM8994_GP_FN_GPIO:
 129                 return "GPIO";
 130         case WM8994_GP_FN_SDOUT:
 131                 return "SDOUT";
 132         case WM8994_GP_FN_IRQ:
 133                 return "IRQ";
 134         case WM8994_GP_FN_TEMPERATURE:
 135                 return "Temperature";
 136         case WM8994_GP_FN_MICBIAS1_DET:
 137                 return "MICBIAS1 detect";
 138         case WM8994_GP_FN_MICBIAS1_SHORT:
 139                 return "MICBIAS1 short";
 140         case WM8994_GP_FN_MICBIAS2_DET:
 141                 return "MICBIAS2 detect";
 142         case WM8994_GP_FN_MICBIAS2_SHORT:
 143                 return "MICBIAS2 short";
 144         case WM8994_GP_FN_FLL1_LOCK:
 145                 return "FLL1 lock";
 146         case WM8994_GP_FN_FLL2_LOCK:
 147                 return "FLL2 lock";
 148         case WM8994_GP_FN_SRC1_LOCK:
 149                 return "SRC1 lock";
 150         case WM8994_GP_FN_SRC2_LOCK:
 151                 return "SRC2 lock";
 152         case WM8994_GP_FN_DRC1_ACT:
 153                 return "DRC1 activity";
 154         case WM8994_GP_FN_DRC2_ACT:
 155                 return "DRC2 activity";
 156         case WM8994_GP_FN_DRC3_ACT:
 157                 return "DRC3 activity";
 158         case WM8994_GP_FN_WSEQ_STATUS:
 159                 return "Write sequencer";
 160         case WM8994_GP_FN_FIFO_ERROR:
 161                 return "FIFO error";
 162         case WM8994_GP_FN_OPCLK:
 163                 return "OPCLK";
 164         case WM8994_GP_FN_THW:
 165                 return "Thermal warning";
 166         case WM8994_GP_FN_DCS_DONE:
 167                 return "DC servo";
 168         case WM8994_GP_FN_FLL1_OUT:
 169                 return "FLL1 output";
 170         case WM8994_GP_FN_FLL2_OUT:
 171                 return "FLL1 output";
 172         default:
 173                 return "Unknown";
 174         }
 175 }
 176
 177 static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 178 {
 179         struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
 180         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 181         int i;
 182
 183         for (i = 0; i < chip->ngpio; i++) {
 184                 int gpio = i + chip->base;
 185                 int reg;
 186                 const char *label;
 187
 188                 /* We report the GPIO even if it's not requested since
 189                  * we're also reporting things like alternate
 190                  * functions which apply even when the GPIO is not in
 191                  * use as a GPIO.
 192                  */
 193                 label = gpiochip_is_requested(chip, i);
 194                 if (!label)
 195                         label = "Unrequested";
 196
 197                 seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
 198
 199                 reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
 200                 if (reg < 0) {
 201                         dev_err(wm8994->dev,
 202                                 "GPIO control %d read failed: %d\n",
 203                                 gpio, reg);
 204                         seq_printf(s, "\n");
 205                         continue;
 206                 }
 207
 208                 if (reg & WM8994_GPN_DIR)
 209                         seq_printf(s, "in ");
 210                 else
 211                         seq_printf(s, "out ");
 212
 213                 if (reg & WM8994_GPN_PU)
 214                         seq_printf(s, "pull up ");
 215
 216                 if (reg & WM8994_GPN_PD)
 217                         seq_printf(s, "pull down ");
 218
 219                 if (reg & WM8994_GPN_POL)
 220                         seq_printf(s, "inverted ");
 221                 else
 222                         seq_printf(s, "noninverted ");
 223
 224                 if (reg & WM8994_GPN_OP_CFG)
 225                         seq_printf(s, "open drain ");
 226                 else
 227                         seq_printf(s, "CMOS ");
 228
 229                 seq_printf(s, "%s (%x)\n",
 230                            wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg);
 231         }
 232 }
 233 #else
 234 #define wm8994_gpio_dbg_show NULL
 235 #endif
 236
 237 static struct gpio_chip template_chip = {
 238         .label                  = "wm8994",
 239         .owner                  = THIS_MODULE,
 240         .request                = wm8994_gpio_request,
 241         .direction_input        = wm8994_gpio_direction_in,
 242         .get                    = wm8994_gpio_get,
 243         .direction_output       = wm8994_gpio_direction_out,
 244         .set                    = wm8994_gpio_set,
 245         .to_irq                 = wm8994_gpio_to_irq,
 246         .dbg_show               = wm8994_gpio_dbg_show,
 247         .can_sleep              = 1,
 248 };
 249
 250 static int __devinit wm8994_gpio_probe(struct platform_device *pdev)
 251 {
 252         struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
 253         struct wm8994_pdata *pdata = wm8994->dev->platform_data;
 254         struct wm8994_gpio *wm8994_gpio;
 255         int ret;
 256
 257         wm8994_gpio = kzalloc(sizeof(*wm8994_gpio), GFP_KERNEL);
 258         if (wm8994_gpio == NULL)
 259                 return -ENOMEM;
 260
 261         wm8994_gpio->wm8994 = wm8994;
 262         wm8994_gpio->gpio_chip = template_chip;
 263         wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
 264         wm8994_gpio->gpio_chip.dev = &pdev->dev;
 265         if (pdata && pdata->gpio_base)
 266                 wm8994_gpio->gpio_chip.base = pdata->gpio_base;
 267         else
 268                 wm8994_gpio->gpio_chip.base = -1;
 269
 270         ret = gpiochip_add(&wm8994_gpio->gpio_chip);
 271         if (ret < 0) {
 272                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
 273                         ret);
 274                 goto err;
 275         }
 276
 277         platform_set_drvdata(pdev, wm8994_gpio);
 278
 279         return ret;
 280
 281 err:
 282         kfree(wm8994_gpio);
 283         return ret;
 284 }
 285
 286 static int __devexit wm8994_gpio_remove(struct platform_device *pdev)
 287 {
 288         struct wm8994_gpio *wm8994_gpio = platform_get_drvdata(pdev);
 289         int ret;
 290
 291         ret = gpiochip_remove(&wm8994_gpio->gpio_chip);
 292         if (ret == 0)
 293                 kfree(wm8994_gpio);
 294
 295         return ret;
 296 }
 297
 298 static struct platform_driver wm8994_gpio_driver = {
 299         .driver.name    = "wm8994-gpio",
 300         .driver.owner   = THIS_MODULE,
 301         .probe          = wm8994_gpio_probe,
 302         .remove         = __devexit_p(wm8994_gpio_remove),
 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");