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/platform_device.h> 7 #include <linux/regmap.h> 8 #include <linux/slab.h> 9 10 #define WCD_PIN_MASK(p) BIT(p) 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 int ret; 49 50 ret = regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET, 51 WCD_PIN_MASK(pin), WCD_PIN_MASK(pin)); 52 if (ret) 53 return ret; 54 55 return regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET, 56 WCD_PIN_MASK(pin), 57 val ? WCD_PIN_MASK(pin) : 0); 58 } 59 60 static int wcd_gpio_get(struct gpio_chip *chip, unsigned int pin) 61 { 62 struct wcd_gpio_data *data = gpiochip_get_data(chip); 63 unsigned int value; 64 65 regmap_read(data->map, WCD_REG_VAL_CTL_OFFSET, &value); 66 67 return !!(value & WCD_PIN_MASK(pin)); 68 } 69 70 static int wcd_gpio_set(struct gpio_chip *chip, unsigned int pin, int val) 71 { 72 struct wcd_gpio_data *data = gpiochip_get_data(chip); 73 74 return regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET, 75 WCD_PIN_MASK(pin), 76 val ? WCD_PIN_MASK(pin) : 0); 77 } 78 79 static int wcd_gpio_probe(struct platform_device *pdev) 80 { 81 struct device *dev = &pdev->dev; 82 struct wcd_gpio_data *data; 83 struct gpio_chip *chip; 84 85 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 86 if (!data) 87 return -ENOMEM; 88 89 data->map = dev_get_regmap(dev->parent, NULL); 90 if (!data->map) { 91 dev_err(dev, "%s: failed to get regmap\n", __func__); 92 return -EINVAL; 93 } 94 95 chip = &data->chip; 96 chip->direction_input = wcd_gpio_direction_input; 97 chip->direction_output = wcd_gpio_direction_output; 98 chip->get_direction = wcd_gpio_get_direction; 99 chip->get = wcd_gpio_get; 100 chip->set = wcd_gpio_set; 101 chip->parent = dev; 102 chip->base = -1; 103 chip->ngpio = WCD934X_NPINS; 104 chip->label = dev_name(dev); 105 chip->can_sleep = true; 106 107 return devm_gpiochip_add_data(dev, chip, data); 108 } 109 110 static const struct of_device_id wcd_gpio_of_match[] = { 111 { .compatible = "qcom,wcd9340-gpio" }, 112 { .compatible = "qcom,wcd9341-gpio" }, 113 { } 114 }; 115 MODULE_DEVICE_TABLE(of, wcd_gpio_of_match); 116 117 static struct platform_driver wcd_gpio_driver = { 118 .driver = { 119 .name = "wcd934x-gpio", 120 .of_match_table = wcd_gpio_of_match, 121 }, 122 .probe = wcd_gpio_probe, 123 }; 124 125 module_platform_driver(wcd_gpio_driver); 126 MODULE_DESCRIPTION("Qualcomm Technologies, Inc WCD GPIO control driver"); 127 MODULE_LICENSE("GPL v2"); 128