drivers/gpio/gpio-wm8350.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * gpiolib support for Wolfson WM835x PMICs
   4  *
   5  * Copyright 2009 Wolfson Microelectronics PLC.
   6  *
   7  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   8  *
   9  */
  10
  11 #include <linux/gpio/driver.h>
  12 #include <linux/kernel.h>
  13 #include <linux/mfd/core.h>
  14 #include <linux/module.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/slab.h>
  17
  18 #include <linux/mfd/wm8350/core.h>
  19 #include <linux/mfd/wm8350/gpio.h>
  20
  21 struct wm8350_gpio_data {
  22         struct wm8350 *wm8350;
  23         struct gpio_chip gpio_chip;
  24 };
  25
  26 static int wm8350_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
  27 {
  28         struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
  29         struct wm8350 *wm8350 = wm8350_gpio->wm8350;
  30
  31         return wm8350_set_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
  32                                1 << offset);
  33 }
  34
  35 static int wm8350_gpio_get(struct gpio_chip *chip, unsigned offset)
  36 {
  37         struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
  38         struct wm8350 *wm8350 = wm8350_gpio->wm8350;
  39         int ret;
  40
  41         ret = wm8350_reg_read(wm8350, WM8350_GPIO_LEVEL);
  42         if (ret < 0)
  43                 return ret;
  44
  45         if (ret & (1 << offset))
  46                 return 1;
  47         else
  48                 return 0;
  49 }
  50
  51 static void wm8350_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
  52 {
  53         struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
  54         struct wm8350 *wm8350 = wm8350_gpio->wm8350;
  55
  56         if (value)
  57                 wm8350_set_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
  58         else
  59                 wm8350_clear_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
  60 }
  61
  62 static int wm8350_gpio_direction_out(struct gpio_chip *chip,
  63                                      unsigned offset, int value)
  64 {
  65         struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
  66         struct wm8350 *wm8350 = wm8350_gpio->wm8350;
  67         int ret;
  68
  69         ret = wm8350_clear_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
  70                                 1 << offset);
  71         if (ret < 0)
  72                 return ret;
  73
  74         /* Don't have an atomic direction/value setup */
  75         wm8350_gpio_set(chip, offset, value);
  76
  77         return 0;
  78 }
  79
  80 static int wm8350_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
  81 {
  82         struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
  83         struct wm8350 *wm8350 = wm8350_gpio->wm8350;
  84
  85         if (!wm8350->irq_base)
  86                 return -EINVAL;
  87
  88         return wm8350->irq_base + WM8350_IRQ_GPIO(offset);
  89 }
  90
  91 static const struct gpio_chip template_chip = {
  92         .label                  = "wm8350",
  93         .owner                  = THIS_MODULE,
  94         .direction_input        = wm8350_gpio_direction_in,
  95         .get                    = wm8350_gpio_get,
  96         .direction_output       = wm8350_gpio_direction_out,
  97         .set                    = wm8350_gpio_set,
  98         .to_irq                 = wm8350_gpio_to_irq,
  99         .can_sleep              = true,
 100 };
 101
 102 static int wm8350_gpio_probe(struct platform_device *pdev)
 103 {
 104         struct wm8350 *wm8350 = dev_get_drvdata(pdev->dev.parent);
 105         struct wm8350_platform_data *pdata = dev_get_platdata(wm8350->dev);
 106         struct wm8350_gpio_data *wm8350_gpio;
 107
 108         wm8350_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8350_gpio),
 109                                    GFP_KERNEL);
 110         if (wm8350_gpio == NULL)
 111                 return -ENOMEM;
 112
 113         wm8350_gpio->wm8350 = wm8350;
 114         wm8350_gpio->gpio_chip = template_chip;
 115         wm8350_gpio->gpio_chip.ngpio = 13;
 116         wm8350_gpio->gpio_chip.parent = &pdev->dev;
 117         if (pdata && pdata->gpio_base)
 118                 wm8350_gpio->gpio_chip.base = pdata->gpio_base;
 119         else
 120                 wm8350_gpio->gpio_chip.base = -1;
 121
 122         return devm_gpiochip_add_data(&pdev->dev, &wm8350_gpio->gpio_chip, wm8350_gpio);
 123 }
 124
 125 static struct platform_driver wm8350_gpio_driver = {
 126         .driver.name    = "wm8350-gpio",
 127         .probe          = wm8350_gpio_probe,
 128 };
 129
 130 static int __init wm8350_gpio_init(void)
 131 {
 132         return platform_driver_register(&wm8350_gpio_driver);
 133 }
 134 subsys_initcall(wm8350_gpio_init);
 135
 136 static void __exit wm8350_gpio_exit(void)
 137 {
 138         platform_driver_unregister(&wm8350_gpio_driver);
 139 }
 140 module_exit(wm8350_gpio_exit);
 141
 142 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 143 MODULE_DESCRIPTION("GPIO interface for WM8350 PMICs");
 144 MODULE_LICENSE("GPL");
 145 MODULE_ALIAS("platform:wm8350-gpio");