1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * GPIO support for Cirrus Logic Madera codecs 4 * 5 * Copyright (C) 2015-2018 Cirrus Logic 6 */ 7 8 #include <linux/gpio/driver.h> 9 #include <linux/kernel.h> 10 #include <linux/module.h> 11 #include <linux/platform_device.h> 12 13 #include <linux/mfd/madera/core.h> 14 #include <linux/mfd/madera/pdata.h> 15 #include <linux/mfd/madera/registers.h> 16 17 struct madera_gpio { 18 struct madera *madera; 19 /* storage space for the gpio_chip we're using */ 20 struct gpio_chip gpio_chip; 21 }; 22 23 static int madera_gpio_get_direction(struct gpio_chip *chip, 24 unsigned int offset) 25 { 26 struct madera_gpio *madera_gpio = gpiochip_get_data(chip); 27 struct madera *madera = madera_gpio->madera; 28 unsigned int reg_offset = 2 * offset; 29 unsigned int val; 30 int ret; 31 32 ret = regmap_read(madera->regmap, MADERA_GPIO1_CTRL_2 + reg_offset, 33 &val); 34 if (ret < 0) 35 return ret; 36 37 return !!(val & MADERA_GP1_DIR_MASK); 38 } 39 40 static int madera_gpio_direction_in(struct gpio_chip *chip, unsigned int offset) 41 { 42 struct madera_gpio *madera_gpio = gpiochip_get_data(chip); 43 struct madera *madera = madera_gpio->madera; 44 unsigned int reg_offset = 2 * offset; 45 46 return regmap_update_bits(madera->regmap, 47 MADERA_GPIO1_CTRL_2 + reg_offset, 48 MADERA_GP1_DIR_MASK, MADERA_GP1_DIR); 49 } 50 51 static int madera_gpio_get(struct gpio_chip *chip, unsigned int offset) 52 { 53 struct madera_gpio *madera_gpio = gpiochip_get_data(chip); 54 struct madera *madera = madera_gpio->madera; 55 unsigned int reg_offset = 2 * offset; 56 unsigned int val; 57 int ret; 58 59 ret = regmap_read(madera->regmap, MADERA_GPIO1_CTRL_1 + reg_offset, 60 &val); 61 if (ret < 0) 62 return ret; 63 64 return !!(val & MADERA_GP1_LVL_MASK); 65 } 66 67 static int madera_gpio_direction_out(struct gpio_chip *chip, 68 unsigned int offset, int value) 69 { 70 struct madera_gpio *madera_gpio = gpiochip_get_data(chip); 71 struct madera *madera = madera_gpio->madera; 72 unsigned int reg_offset = 2 * offset; 73 unsigned int reg_val = value ? MADERA_GP1_LVL : 0; 74 int ret; 75 76 ret = regmap_update_bits(madera->regmap, 77 MADERA_GPIO1_CTRL_2 + reg_offset, 78 MADERA_GP1_DIR_MASK, 0); 79 if (ret < 0) 80 return ret; 81 82 return regmap_update_bits(madera->regmap, 83 MADERA_GPIO1_CTRL_1 + reg_offset, 84 MADERA_GP1_LVL_MASK, reg_val); 85 } 86 87 static void madera_gpio_set(struct gpio_chip *chip, unsigned int offset, 88 int value) 89 { 90 struct madera_gpio *madera_gpio = gpiochip_get_data(chip); 91 struct madera *madera = madera_gpio->madera; 92 unsigned int reg_offset = 2 * offset; 93 unsigned int reg_val = value ? MADERA_GP1_LVL : 0; 94 int ret; 95 96 ret = regmap_update_bits(madera->regmap, 97 MADERA_GPIO1_CTRL_1 + reg_offset, 98 MADERA_GP1_LVL_MASK, reg_val); 99 100 /* set() doesn't return an error so log a warning */ 101 if (ret) 102 dev_warn(madera->dev, "Failed to write to 0x%x (%d)\n", 103 MADERA_GPIO1_CTRL_1 + reg_offset, ret); 104 } 105 106 static const struct gpio_chip madera_gpio_chip = { 107 .label = "madera", 108 .owner = THIS_MODULE, 109 .request = gpiochip_generic_request, 110 .free = gpiochip_generic_free, 111 .get_direction = madera_gpio_get_direction, 112 .direction_input = madera_gpio_direction_in, 113 .get = madera_gpio_get, 114 .direction_output = madera_gpio_direction_out, 115 .set = madera_gpio_set, 116 .set_config = gpiochip_generic_config, 117 .can_sleep = true, 118 }; 119 120 static int madera_gpio_probe(struct platform_device *pdev) 121 { 122 struct madera *madera = dev_get_drvdata(pdev->dev.parent); 123 struct madera_pdata *pdata = dev_get_platdata(madera->dev); 124 struct madera_gpio *madera_gpio; 125 int ret; 126 127 madera_gpio = devm_kzalloc(&pdev->dev, sizeof(*madera_gpio), 128 GFP_KERNEL); 129 if (!madera_gpio) 130 return -ENOMEM; 131 132 madera_gpio->madera = madera; 133 134 /* Construct suitable gpio_chip from the template in madera_gpio_chip */ 135 madera_gpio->gpio_chip = madera_gpio_chip; 136 madera_gpio->gpio_chip.parent = pdev->dev.parent; 137 138 switch (madera->type) { 139 case CS47L35: 140 madera_gpio->gpio_chip.ngpio = CS47L35_NUM_GPIOS; 141 break; 142 case CS47L85: 143 case WM1840: 144 madera_gpio->gpio_chip.ngpio = CS47L85_NUM_GPIOS; 145 break; 146 case CS47L90: 147 case CS47L91: 148 madera_gpio->gpio_chip.ngpio = CS47L90_NUM_GPIOS; 149 break; 150 default: 151 dev_err(&pdev->dev, "Unknown chip variant %d\n", madera->type); 152 return -EINVAL; 153 } 154 155 /* We want to be usable on systems that don't use devicetree or acpi */ 156 if (pdata && pdata->gpio_base) 157 madera_gpio->gpio_chip.base = pdata->gpio_base; 158 else 159 madera_gpio->gpio_chip.base = -1; 160 161 ret = devm_gpiochip_add_data(&pdev->dev, 162 &madera_gpio->gpio_chip, 163 madera_gpio); 164 if (ret < 0) { 165 dev_dbg(&pdev->dev, "Could not register gpiochip, %d\n", ret); 166 return ret; 167 } 168 169 /* 170 * This is part of a composite MFD device which can only be used with 171 * the corresponding pinctrl driver. On all supported silicon the GPIO 172 * to pinctrl mapping is fixed in the silicon, so we register it 173 * explicitly instead of requiring a redundant gpio-ranges in the 174 * devicetree. 175 * In any case we also want to work on systems that don't use devicetree 176 * or acpi. 177 */ 178 ret = gpiochip_add_pin_range(&madera_gpio->gpio_chip, "madera-pinctrl", 179 0, 0, madera_gpio->gpio_chip.ngpio); 180 if (ret) { 181 dev_dbg(&pdev->dev, "Failed to add pin range (%d)\n", ret); 182 return ret; 183 } 184 185 return 0; 186 } 187 188 static struct platform_driver madera_gpio_driver = { 189 .driver = { 190 .name = "madera-gpio", 191 }, 192 .probe = madera_gpio_probe, 193 }; 194 195 module_platform_driver(madera_gpio_driver); 196 197 MODULE_SOFTDEP("pre: pinctrl-madera"); 198 MODULE_DESCRIPTION("GPIO interface for Madera codecs"); 199 MODULE_AUTHOR("Nariman Poushin <nariman@opensource.cirrus.com>"); 200 MODULE_AUTHOR("Richard Fitzgerald <rf@opensource.cirrus.com>"); 201 MODULE_LICENSE("GPL v2"); 202 MODULE_ALIAS("platform:madera-gpio"); 203