1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (c) 2019, Linaro Limited 3 4 #include <linux/module.h> 5 #include <linux/gpio/driver.h> 6 #include <linux/regmap.h> 7 #include <linux/slab.h> 8 #include <linux/of_device.h> 9 10 #define WCD_PIN_MASK(p) BIT(p - 1) 11 #define WCD_REG_DIR_CTL_OFFSET 0x42 12 #define WCD_REG_VAL_CTL_OFFSET 0x43 13 #define WCD934X_NPINS 5 14 15 struct wcd_gpio_data { 16 struct regmap *map; 17 struct gpio_chip chip; 18 }; 19 20 static int wcd_gpio_get_direction(struct gpio_chip *chip, unsigned int pin) 21 { 22 struct wcd_gpio_data *data = gpiochip_get_data(chip); 23 unsigned int value; 24 int ret; 25 26 ret = regmap_read(data->map, WCD_REG_DIR_CTL_OFFSET, &value); 27 if (ret < 0) 28 return ret; 29 30 if (value & WCD_PIN_MASK(pin)) 31 return GPIO_LINE_DIRECTION_OUT; 32 33 return GPIO_LINE_DIRECTION_IN; 34 } 35 36 static int wcd_gpio_direction_input(struct gpio_chip *chip, unsigned int pin) 37 { 38 struct wcd_gpio_data *data = gpiochip_get_data(chip); 39 40 return regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET, 41 WCD_PIN_MASK(pin), 0); 42 } 43 44 static int wcd_gpio_direction_output(struct gpio_chip *chip, unsigned int pin, 45 int val) 46 { 47 struct wcd_gpio_data *data = gpiochip_get_data(chip); 48 49 regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET, 50 WCD_PIN_MASK(pin), WCD_PIN_MASK(pin)); 51 52 return regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET, 53 WCD_PIN_MASK(pin), 54 val ? WCD_PIN_MASK(pin) : 0); 55 } 56 57 static int wcd_gpio_get(struct gpio_chip *chip, unsigned int pin) 58 { 59 struct wcd_gpio_data *data = gpiochip_get_data(chip); 60 int value; 61 62 regmap_read(data->map, WCD_REG_VAL_CTL_OFFSET, &value); 63 64 return !!(value && WCD_PIN_MASK(pin)); 65 } 66 67 static void wcd_gpio_set(struct gpio_chip *chip, unsigned int pin, int val) 68 { 69 wcd_gpio_direction_output(chip, pin, val); 70 } 71 72 static int wcd_gpio_probe(struct platform_device *pdev) 73 { 74 struct device *dev = &pdev->dev; 75 struct wcd_gpio_data *data; 76 struct gpio_chip *chip; 77 78 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 79 if (!data) 80 return -ENOMEM; 81 82 data->map = dev_get_regmap(dev->parent, NULL); 83 if (!data->map) { 84 dev_err(dev, "%s: failed to get regmap\n", __func__); 85 return -EINVAL; 86 } 87 88 chip = &data->chip; 89 chip->direction_input = wcd_gpio_direction_input; 90 chip->direction_output = wcd_gpio_direction_output; 91 chip->get_direction = wcd_gpio_get_direction; 92 chip->get = wcd_gpio_get; 93 chip->set = wcd_gpio_set; 94 chip->parent = dev; 95 chip->base = -1; 96 chip->ngpio = WCD934X_NPINS; 97 chip->label = dev_name(dev); 98 chip->of_gpio_n_cells = 2; 99 chip->can_sleep = false; 100 101 return devm_gpiochip_add_data(dev, chip, data); 102 } 103 104 static const struct of_device_id wcd_gpio_of_match[] = { 105 { .compatible = "qcom,wcd9340-gpio" }, 106 { .compatible = "qcom,wcd9341-gpio" }, 107 { } 108 }; 109 MODULE_DEVICE_TABLE(of, wcd_gpio_of_match); 110 111 static struct platform_driver wcd_gpio_driver = { 112 .driver = { 113 .name = "wcd934x-gpio", 114 .of_match_table = wcd_gpio_of_match, 115 }, 116 .probe = wcd_gpio_probe, 117 }; 118 119 module_platform_driver(wcd_gpio_driver); 120 MODULE_DESCRIPTION("Qualcomm Technologies, Inc WCD GPIO control driver"); 121 MODULE_LICENSE("GPL v2"); 122