drivers/gpio/gpio-wm8994.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * gpiolib support for Wolfson WM8994
   4  *
   5  * Copyright 2009 Wolfson Microelectronics PLC.
   6  *
   7  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   8  *
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/slab.h>
  13 #include <linux/module.h>
  14 #include <linux/gpio/driver.h>
  15 #include <linux/mfd/core.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/seq_file.h>
  18 #include <linux/regmap.h>
  19
  20 #include <linux/mfd/wm8994/core.h>
  21 #include <linux/mfd/wm8994/pdata.h>
  22 #include <linux/mfd/wm8994/gpio.h>
  23 #include <linux/mfd/wm8994/registers.h>
  24
  25 struct wm8994_gpio {
  26         struct wm8994 *wm8994;
  27         struct gpio_chip gpio_chip;
  28 };
  29
  30 static int wm8994_gpio_request(struct gpio_chip *chip, unsigned offset)
  31 {
  32         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
  33         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  34
  35         switch (wm8994->type) {
  36         case WM8958:
  37                 switch (offset) {
  38                 case 1:
  39                 case 2:
  40                 case 3:
  41                 case 4:
  42                 case 6:
  43                         return -EINVAL;
  44                 }
  45                 break;
  46         default:
  47                 break;
  48         }
  49
  50         return 0;
  51 }
  52
  53 static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
  54 {
  55         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
  56         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  57
  58         return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
  59                                WM8994_GPN_DIR, WM8994_GPN_DIR);
  60 }
  61
  62 static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset)
  63 {
  64         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
  65         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  66         int ret;
  67
  68         ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset);
  69         if (ret < 0)
  70                 return ret;
  71
  72         if (ret & WM8994_GPN_LVL)
  73                 return 1;
  74         else
  75                 return 0;
  76 }
  77
  78 static int wm8994_gpio_direction_out(struct gpio_chip *chip,
  79                                      unsigned offset, int value)
  80 {
  81         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
  82         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  83
  84         if (value)
  85                 value = WM8994_GPN_LVL;
  86
  87         return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
  88                                WM8994_GPN_DIR | WM8994_GPN_LVL, value);
  89 }
  90
  91 static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
  92 {
  93         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
  94         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
  95
  96         if (value)
  97                 value = WM8994_GPN_LVL;
  98
  99         wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value);
 100 }
 101
 102 static int wm8994_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
 103                                   unsigned long config)
 104 {
 105         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
 106         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 107
 108         switch (pinconf_to_config_param(config)) {
 109         case PIN_CONFIG_DRIVE_OPEN_DRAIN:
 110                 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
 111                                        WM8994_GPN_OP_CFG_MASK,
 112                                        WM8994_GPN_OP_CFG);
 113         case PIN_CONFIG_DRIVE_PUSH_PULL:
 114                 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
 115                                        WM8994_GPN_OP_CFG_MASK, 0);
 116         default:
 117                 break;
 118         }
 119
 120         return -ENOTSUPP;
 121 }
 122
 123 static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 124 {
 125         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
 126         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 127
 128         return regmap_irq_get_virq(wm8994->irq_data, offset);
 129 }
 130
 131
 132 #ifdef CONFIG_DEBUG_FS
 133 static const char *wm8994_gpio_fn(u16 fn)
 134 {
 135         switch (fn) {
 136         case WM8994_GP_FN_PIN_SPECIFIC:
 137                 return "pin-specific";
 138         case WM8994_GP_FN_GPIO:
 139                 return "GPIO";
 140         case WM8994_GP_FN_SDOUT:
 141                 return "SDOUT";
 142         case WM8994_GP_FN_IRQ:
 143                 return "IRQ";
 144         case WM8994_GP_FN_TEMPERATURE:
 145                 return "Temperature";
 146         case WM8994_GP_FN_MICBIAS1_DET:
 147                 return "MICBIAS1 detect";
 148         case WM8994_GP_FN_MICBIAS1_SHORT:
 149                 return "MICBIAS1 short";
 150         case WM8994_GP_FN_MICBIAS2_DET:
 151                 return "MICBIAS2 detect";
 152         case WM8994_GP_FN_MICBIAS2_SHORT:
 153                 return "MICBIAS2 short";
 154         case WM8994_GP_FN_FLL1_LOCK:
 155                 return "FLL1 lock";
 156         case WM8994_GP_FN_FLL2_LOCK:
 157                 return "FLL2 lock";
 158         case WM8994_GP_FN_SRC1_LOCK:
 159                 return "SRC1 lock";
 160         case WM8994_GP_FN_SRC2_LOCK:
 161                 return "SRC2 lock";
 162         case WM8994_GP_FN_DRC1_ACT:
 163                 return "DRC1 activity";
 164         case WM8994_GP_FN_DRC2_ACT:
 165                 return "DRC2 activity";
 166         case WM8994_GP_FN_DRC3_ACT:
 167                 return "DRC3 activity";
 168         case WM8994_GP_FN_WSEQ_STATUS:
 169                 return "Write sequencer";
 170         case WM8994_GP_FN_FIFO_ERROR:
 171                 return "FIFO error";
 172         case WM8994_GP_FN_OPCLK:
 173                 return "OPCLK";
 174         case WM8994_GP_FN_THW:
 175                 return "Thermal warning";
 176         case WM8994_GP_FN_DCS_DONE:
 177                 return "DC servo";
 178         case WM8994_GP_FN_FLL1_OUT:
 179                 return "FLL1 output";
 180         case WM8994_GP_FN_FLL2_OUT:
 181                 return "FLL1 output";
 182         default:
 183                 return "Unknown";
 184         }
 185 }
 186
 187 static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 188 {
 189         struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
 190         struct wm8994 *wm8994 = wm8994_gpio->wm8994;
 191         int i;
 192
 193         for (i = 0; i < chip->ngpio; i++) {
 194                 int gpio = i + chip->base;
 195                 int reg;
 196                 const char *label;
 197
 198                 /* We report the GPIO even if it's not requested since
 199                  * we're also reporting things like alternate
 200                  * functions which apply even when the GPIO is not in
 201                  * use as a GPIO.
 202                  */
 203                 label = gpiochip_is_requested(chip, i);
 204                 if (!label)
 205                         label = "Unrequested";
 206
 207                 seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
 208
 209                 reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
 210                 if (reg < 0) {
 211                         dev_err(wm8994->dev,
 212                                 "GPIO control %d read failed: %d\n",
 213                                 gpio, reg);
 214                         seq_printf(s, "\n");
 215                         continue;
 216                 }
 217
 218                 if (reg & WM8994_GPN_DIR)
 219                         seq_printf(s, "in ");
 220                 else
 221                         seq_printf(s, "out ");
 222
 223                 if (reg & WM8994_GPN_PU)
 224                         seq_printf(s, "pull up ");
 225
 226                 if (reg & WM8994_GPN_PD)
 227                         seq_printf(s, "pull down ");
 228
 229                 if (reg & WM8994_GPN_POL)
 230                         seq_printf(s, "inverted ");
 231                 else
 232                         seq_printf(s, "noninverted ");
 233
 234                 if (reg & WM8994_GPN_OP_CFG)
 235                         seq_printf(s, "open drain ");
 236                 else
 237                         seq_printf(s, "push-pull ");
 238
 239                 seq_printf(s, "%s (%x)\n",
 240                            wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg);
 241         }
 242 }
 243 #else
 244 #define wm8994_gpio_dbg_show NULL
 245 #endif
 246
 247 static const struct gpio_chip template_chip = {
 248         .label                  = "wm8994",
 249         .owner                  = THIS_MODULE,
 250         .request                = wm8994_gpio_request,
 251         .direction_input        = wm8994_gpio_direction_in,
 252         .get                    = wm8994_gpio_get,
 253         .direction_output       = wm8994_gpio_direction_out,
 254         .set                    = wm8994_gpio_set,
 255         .set_config             = wm8994_gpio_set_config,
 256         .to_irq                 = wm8994_gpio_to_irq,
 257         .dbg_show               = wm8994_gpio_dbg_show,
 258         .can_sleep              = true,
 259 };
 260
 261 static int wm8994_gpio_probe(struct platform_device *pdev)
 262 {
 263         struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
 264         struct wm8994_pdata *pdata = dev_get_platdata(wm8994->dev);
 265         struct wm8994_gpio *wm8994_gpio;
 266         int ret;
 267
 268         wm8994_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8994_gpio),
 269                                    GFP_KERNEL);
 270         if (wm8994_gpio == NULL)
 271                 return -ENOMEM;
 272
 273         wm8994_gpio->wm8994 = wm8994;
 274         wm8994_gpio->gpio_chip = template_chip;
 275         wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
 276         wm8994_gpio->gpio_chip.parent = &pdev->dev;
 277         if (pdata && pdata->gpio_base)
 278                 wm8994_gpio->gpio_chip.base = pdata->gpio_base;
 279         else
 280                 wm8994_gpio->gpio_chip.base = -1;
 281
 282         ret = devm_gpiochip_add_data(&pdev->dev, &wm8994_gpio->gpio_chip,
 283                                      wm8994_gpio);
 284         if (ret < 0) {
 285                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
 286                         ret);
 287                 return ret;
 288         }
 289
 290         platform_set_drvdata(pdev, wm8994_gpio);
 291
 292         return ret;
 293 }
 294
 295 static struct platform_driver wm8994_gpio_driver = {
 296         .driver.name    = "wm8994-gpio",
 297         .probe          = wm8994_gpio_probe,
 298 };
 299
 300 static int __init wm8994_gpio_init(void)
 301 {
 302         return platform_driver_register(&wm8994_gpio_driver);
 303 }
 304 subsys_initcall(wm8994_gpio_init);
 305
 306 static void __exit wm8994_gpio_exit(void)
 307 {
 308         platform_driver_unregister(&wm8994_gpio_driver);
 309 }
 310 module_exit(wm8994_gpio_exit);
 311
 312 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 313 MODULE_DESCRIPTION("GPIO interface for WM8994");
 314 MODULE_LICENSE("GPL");
 315 MODULE_ALIAS("platform:wm8994-gpio");