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/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
  19 #include <linux/mfd/wm8350/core.h>
  20 #include <linux/mfd/wm8350/gpio.h>
  21
  22 struct wm8350_gpio_data {
  23         struct wm8350 *wm8350;
  24         struct gpio_chip gpio_chip;
  25 };
  26
  27 static int wm8350_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
  28 {
  29         struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
  30         struct wm8350 *wm8350 = wm8350_gpio->wm8350;
  31
  32         return wm8350_set_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
  33                                1 << offset);
  34 }
  35
  36 static int wm8350_gpio_get(struct gpio_chip *chip, unsigned offset)
  37 {
  38         struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
  39         struct wm8350 *wm8350 = wm8350_gpio->wm8350;
  40         int ret;
  41
  42         ret = wm8350_reg_read(wm8350, WM8350_GPIO_LEVEL);
  43         if (ret < 0)
  44                 return ret;
  45
  46         if (ret & (1 << offset))
  47                 return 1;
  48         else
  49                 return 0;
  50 }
  51
  52 static void wm8350_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
  53 {
  54         struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
  55         struct wm8350 *wm8350 = wm8350_gpio->wm8350;
  56
  57         if (value)
  58                 wm8350_set_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
  59         else
  60                 wm8350_clear_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
  61 }
  62
  63 static int wm8350_gpio_direction_out(struct gpio_chip *chip,
  64                                      unsigned offset, int value)
  65 {
  66         struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
  67         struct wm8350 *wm8350 = wm8350_gpio->wm8350;
  68         int ret;
  69
  70         ret = wm8350_clear_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
  71                                 1 << offset);
  72         if (ret < 0)
  73                 return ret;
  74
  75         /* Don't have an atomic direction/value setup */
  76         wm8350_gpio_set(chip, offset, value);
  77
  78         return 0;
  79 }
  80
  81 static int wm8350_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
  82 {
  83         struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
  84         struct wm8350 *wm8350 = wm8350_gpio->wm8350;
  85
  86         if (!wm8350->irq_base)
  87                 return -EINVAL;
  88
  89         return wm8350->irq_base + WM8350_IRQ_GPIO(offset);
  90 }
  91
  92 static const struct gpio_chip template_chip = {
  93         .label                  = "wm8350",
  94         .owner                  = THIS_MODULE,
  95         .direction_input        = wm8350_gpio_direction_in,
  96         .get                    = wm8350_gpio_get,
  97         .direction_output       = wm8350_gpio_direction_out,
  98         .set                    = wm8350_gpio_set,
  99         .to_irq                 = wm8350_gpio_to_irq,
 100         .can_sleep              = true,
 101 };
 102
 103 static int wm8350_gpio_probe(struct platform_device *pdev)
 104 {
 105         struct wm8350 *wm8350 = dev_get_drvdata(pdev->dev.parent);
 106         struct wm8350_platform_data *pdata = dev_get_platdata(wm8350->dev);
 107         struct wm8350_gpio_data *wm8350_gpio;
 108         int ret;
 109
 110         wm8350_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8350_gpio),
 111                                    GFP_KERNEL);
 112         if (wm8350_gpio == NULL)
 113                 return -ENOMEM;
 114
 115         wm8350_gpio->wm8350 = wm8350;
 116         wm8350_gpio->gpio_chip = template_chip;
 117         wm8350_gpio->gpio_chip.ngpio = 13;
 118         wm8350_gpio->gpio_chip.parent = &pdev->dev;
 119         if (pdata && pdata->gpio_base)
 120                 wm8350_gpio->gpio_chip.base = pdata->gpio_base;
 121         else
 122                 wm8350_gpio->gpio_chip.base = -1;
 123
 124         ret = devm_gpiochip_add_data(&pdev->dev, &wm8350_gpio->gpio_chip,
 125                                      wm8350_gpio);
 126         if (ret < 0) {
 127                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
 128                 return ret;
 129         }
 130
 131         platform_set_drvdata(pdev, wm8350_gpio);
 132
 133         return ret;
 134 }
 135
 136 static struct platform_driver wm8350_gpio_driver = {
 137         .driver.name    = "wm8350-gpio",
 138         .probe          = wm8350_gpio_probe,
 139 };
 140
 141 static int __init wm8350_gpio_init(void)
 142 {
 143         return platform_driver_register(&wm8350_gpio_driver);
 144 }
 145 subsys_initcall(wm8350_gpio_init);
 146
 147 static void __exit wm8350_gpio_exit(void)
 148 {
 149         platform_driver_unregister(&wm8350_gpio_driver);
 150 }
 151 module_exit(wm8350_gpio_exit);
 152
 153 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 154 MODULE_DESCRIPTION("GPIO interface for WM8350 PMICs");
 155 MODULE_LICENSE("GPL");
 156 MODULE_ALIAS("platform:wm8350-gpio");