1 // SPDX-License-Identifier: GPL-2.0 2 // 3 // Copyright (C) 2018 BayLibre SAS 4 // Author: Bartosz Golaszewski <bgolaszewski@baylibre.com> 5 // 6 // GPIO driver for MAXIM 77650/77651 charger/power-supply. 7 8 #include <linux/gpio/driver.h> 9 #include <linux/i2c.h> 10 #include <linux/mfd/max77650.h> 11 #include <linux/module.h> 12 #include <linux/platform_device.h> 13 #include <linux/regmap.h> 14 15 #define MAX77650_GPIO_DIR_MASK BIT(0) 16 #define MAX77650_GPIO_INVAL_MASK BIT(1) 17 #define MAX77650_GPIO_DRV_MASK BIT(2) 18 #define MAX77650_GPIO_OUTVAL_MASK BIT(3) 19 #define MAX77650_GPIO_DEBOUNCE_MASK BIT(4) 20 21 #define MAX77650_GPIO_DIR_OUT 0x00 22 #define MAX77650_GPIO_DIR_IN BIT(0) 23 #define MAX77650_GPIO_OUT_LOW 0x00 24 #define MAX77650_GPIO_OUT_HIGH BIT(3) 25 #define MAX77650_GPIO_DRV_OPEN_DRAIN 0x00 26 #define MAX77650_GPIO_DRV_PUSH_PULL BIT(2) 27 #define MAX77650_GPIO_DEBOUNCE BIT(4) 28 29 #define MAX77650_GPIO_DIR_BITS(_reg) \ 30 ((_reg) & MAX77650_GPIO_DIR_MASK) 31 #define MAX77650_GPIO_INVAL_BITS(_reg) \ 32 (((_reg) & MAX77650_GPIO_INVAL_MASK) >> 1) 33 34 struct max77650_gpio_chip { 35 struct regmap *map; 36 struct gpio_chip gc; 37 int irq; 38 }; 39 40 static int max77650_gpio_direction_input(struct gpio_chip *gc, 41 unsigned int offset) 42 { 43 struct max77650_gpio_chip *chip = gpiochip_get_data(gc); 44 45 return regmap_update_bits(chip->map, 46 MAX77650_REG_CNFG_GPIO, 47 MAX77650_GPIO_DIR_MASK, 48 MAX77650_GPIO_DIR_IN); 49 } 50 51 static int max77650_gpio_direction_output(struct gpio_chip *gc, 52 unsigned int offset, int value) 53 { 54 struct max77650_gpio_chip *chip = gpiochip_get_data(gc); 55 int mask, regval; 56 57 mask = MAX77650_GPIO_DIR_MASK | MAX77650_GPIO_OUTVAL_MASK; 58 regval = value ? MAX77650_GPIO_OUT_HIGH : MAX77650_GPIO_OUT_LOW; 59 regval |= MAX77650_GPIO_DIR_OUT; 60 61 return regmap_update_bits(chip->map, 62 MAX77650_REG_CNFG_GPIO, mask, regval); 63 } 64 65 static void max77650_gpio_set_value(struct gpio_chip *gc, 66 unsigned int offset, int value) 67 { 68 struct max77650_gpio_chip *chip = gpiochip_get_data(gc); 69 int rv, regval; 70 71 regval = value ? MAX77650_GPIO_OUT_HIGH : MAX77650_GPIO_OUT_LOW; 72 73 rv = regmap_update_bits(chip->map, MAX77650_REG_CNFG_GPIO, 74 MAX77650_GPIO_OUTVAL_MASK, regval); 75 if (rv) 76 dev_err(gc->parent, "cannot set GPIO value: %d\n", rv); 77 } 78 79 static int max77650_gpio_get_value(struct gpio_chip *gc, 80 unsigned int offset) 81 { 82 struct max77650_gpio_chip *chip = gpiochip_get_data(gc); 83 unsigned int val; 84 int rv; 85 86 rv = regmap_read(chip->map, MAX77650_REG_CNFG_GPIO, &val); 87 if (rv) 88 return rv; 89 90 return MAX77650_GPIO_INVAL_BITS(val); 91 } 92 93 static int max77650_gpio_get_direction(struct gpio_chip *gc, 94 unsigned int offset) 95 { 96 struct max77650_gpio_chip *chip = gpiochip_get_data(gc); 97 unsigned int val; 98 int rv; 99 100 rv = regmap_read(chip->map, MAX77650_REG_CNFG_GPIO, &val); 101 if (rv) 102 return rv; 103 104 return MAX77650_GPIO_DIR_BITS(val); 105 } 106 107 static int max77650_gpio_set_config(struct gpio_chip *gc, 108 unsigned int offset, unsigned long cfg) 109 { 110 struct max77650_gpio_chip *chip = gpiochip_get_data(gc); 111 112 switch (pinconf_to_config_param(cfg)) { 113 case PIN_CONFIG_DRIVE_OPEN_DRAIN: 114 return regmap_update_bits(chip->map, 115 MAX77650_REG_CNFG_GPIO, 116 MAX77650_GPIO_DRV_MASK, 117 MAX77650_GPIO_DRV_OPEN_DRAIN); 118 case PIN_CONFIG_DRIVE_PUSH_PULL: 119 return regmap_update_bits(chip->map, 120 MAX77650_REG_CNFG_GPIO, 121 MAX77650_GPIO_DRV_MASK, 122 MAX77650_GPIO_DRV_PUSH_PULL); 123 case PIN_CONFIG_INPUT_DEBOUNCE: 124 return regmap_update_bits(chip->map, 125 MAX77650_REG_CNFG_GPIO, 126 MAX77650_GPIO_DEBOUNCE_MASK, 127 MAX77650_GPIO_DEBOUNCE); 128 default: 129 return -ENOTSUPP; 130 } 131 } 132 133 static int max77650_gpio_to_irq(struct gpio_chip *gc, unsigned int offset) 134 { 135 struct max77650_gpio_chip *chip = gpiochip_get_data(gc); 136 137 return chip->irq; 138 } 139 140 static int max77650_gpio_probe(struct platform_device *pdev) 141 { 142 struct max77650_gpio_chip *chip; 143 struct device *dev, *parent; 144 struct i2c_client *i2c; 145 146 dev = &pdev->dev; 147 parent = dev->parent; 148 i2c = to_i2c_client(parent); 149 150 chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL); 151 if (!chip) 152 return -ENOMEM; 153 154 chip->map = dev_get_regmap(parent, NULL); 155 if (!chip->map) 156 return -ENODEV; 157 158 chip->irq = platform_get_irq_byname(pdev, "GPI"); 159 if (chip->irq < 0) 160 return chip->irq; 161 162 chip->gc.base = -1; 163 chip->gc.ngpio = 1; 164 chip->gc.label = i2c->name; 165 chip->gc.parent = dev; 166 chip->gc.owner = THIS_MODULE; 167 chip->gc.can_sleep = true; 168 169 chip->gc.direction_input = max77650_gpio_direction_input; 170 chip->gc.direction_output = max77650_gpio_direction_output; 171 chip->gc.set = max77650_gpio_set_value; 172 chip->gc.get = max77650_gpio_get_value; 173 chip->gc.get_direction = max77650_gpio_get_direction; 174 chip->gc.set_config = max77650_gpio_set_config; 175 chip->gc.to_irq = max77650_gpio_to_irq; 176 177 return devm_gpiochip_add_data(dev, &chip->gc, chip); 178 } 179 180 static struct platform_driver max77650_gpio_driver = { 181 .driver = { 182 .name = "max77650-gpio", 183 }, 184 .probe = max77650_gpio_probe, 185 }; 186 module_platform_driver(max77650_gpio_driver); 187 188 MODULE_DESCRIPTION("MAXIM 77650/77651 GPIO driver"); 189 MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>"); 190 MODULE_LICENSE("GPL v2"); 191