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