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1// SPDX-License-Identifier: GPL-2.02/*3 * GPIO driver for TI TPS65219 PMICs4 *5 * Copyright (C) 2022 Texas Instruments Incorporated - http://www.ti.com/6 */7 8#include <linux/bits.h>9#include <linux/gpio/driver.h>10#include <linux/mfd/tps65219.h>11#include <linux/module.h>12#include <linux/platform_device.h>13#include <linux/regmap.h>14 15#define TPS65219_GPIO0_DIR_MASK BIT(3)16#define TPS65219_GPIO0_OFFSET 217#define TPS65219_GPIO0_IDX 018#define TPS65219_GPIO_DIR_IN 119#define TPS65219_GPIO_DIR_OUT 020 21struct tps65219_gpio {22 struct gpio_chip gpio_chip;23 struct tps65219 *tps;24};25 26static int tps65219_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)27{28 struct tps65219_gpio *gpio = gpiochip_get_data(gc);29 int ret, val;30 31 if (offset != TPS65219_GPIO0_IDX)32 return GPIO_LINE_DIRECTION_OUT;33 34 ret = regmap_read(gpio->tps->regmap, TPS65219_REG_MFP_1_CONFIG, &val);35 if (ret)36 return ret;37 38 return !!(val & TPS65219_GPIO0_DIR_MASK);39}40 41static int tps65219_gpio_get(struct gpio_chip *gc, unsigned int offset)42{43 struct tps65219_gpio *gpio = gpiochip_get_data(gc);44 struct device *dev = gpio->tps->dev;45 int ret, val;46 47 if (offset != TPS65219_GPIO0_IDX) {48 dev_err(dev, "GPIO%d is output only, cannot get\n", offset);49 return -ENOTSUPP;50 }51 52 ret = regmap_read(gpio->tps->regmap, TPS65219_REG_MFP_CTRL, &val);53 if (ret)54 return ret;55 56 ret = !!(val & BIT(TPS65219_MFP_GPIO_STATUS_MASK));57 dev_warn(dev, "GPIO%d = %d, MULTI_DEVICE_ENABLE, not a standard GPIO\n", offset, ret);58 59 /*60 * Depending on NVM config, return an error if direction is output, otherwise the GPIO061 * status bit.62 */63 64 if (tps65219_gpio_get_direction(gc, offset) == TPS65219_GPIO_DIR_OUT)65 return -ENOTSUPP;66 67 return ret;68}69 70static void tps65219_gpio_set(struct gpio_chip *gc, unsigned int offset, int value)71{72 struct tps65219_gpio *gpio = gpiochip_get_data(gc);73 struct device *dev = gpio->tps->dev;74 int v, mask, bit;75 76 bit = (offset == TPS65219_GPIO0_IDX) ? TPS65219_GPIO0_OFFSET : offset - 1;77 78 mask = BIT(bit);79 v = value ? mask : 0;80 81 if (regmap_update_bits(gpio->tps->regmap, TPS65219_REG_GENERAL_CONFIG, mask, v))82 dev_err(dev, "GPIO%d, set to value %d failed.\n", offset, value);83}84 85static int tps65219_gpio_change_direction(struct gpio_chip *gc, unsigned int offset,86 unsigned int direction)87{88 struct tps65219_gpio *gpio = gpiochip_get_data(gc);89 struct device *dev = gpio->tps->dev;90 91 /*92 * Documentation is stating that GPIO0 direction must not be changed in Linux:93 * Table 8-34. MFP_1_CONFIG(3): MULTI_DEVICE_ENABLE, should only be changed in INITIALIZE94 * state (prior to ON Request).95 * Set statically by NVM, changing direction in application can cause a hang.96 * Below can be used for test purpose only.97 */98 99#if 0100 int ret = regmap_update_bits(gpio->tps->regmap, TPS65219_REG_MFP_1_CONFIG,101 TPS65219_GPIO0_DIR_MASK, direction);102 if (ret) {103 dev_err(dev,104 "GPIO DEBUG enabled: Fail to change direction to %u for GPIO%d.\n",105 direction, offset);106 return ret;107 }108#endif109 110 dev_err(dev,111 "GPIO%d direction set by NVM, change to %u failed, not allowed by specification\n",112 offset, direction);113 114 return -ENOTSUPP;115}116 117static int tps65219_gpio_direction_input(struct gpio_chip *gc, unsigned int offset)118{119 struct tps65219_gpio *gpio = gpiochip_get_data(gc);120 struct device *dev = gpio->tps->dev;121 122 if (offset != TPS65219_GPIO0_IDX) {123 dev_err(dev, "GPIO%d is output only, cannot change to input\n", offset);124 return -ENOTSUPP;125 }126 127 if (tps65219_gpio_get_direction(gc, offset) == TPS65219_GPIO_DIR_IN)128 return 0;129 130 return tps65219_gpio_change_direction(gc, offset, TPS65219_GPIO_DIR_IN);131}132 133static int tps65219_gpio_direction_output(struct gpio_chip *gc, unsigned int offset, int value)134{135 tps65219_gpio_set(gc, offset, value);136 if (offset != TPS65219_GPIO0_IDX)137 return 0;138 139 if (tps65219_gpio_get_direction(gc, offset) == TPS65219_GPIO_DIR_OUT)140 return 0;141 142 return tps65219_gpio_change_direction(gc, offset, TPS65219_GPIO_DIR_OUT);143}144 145static const struct gpio_chip tps65219_template_chip = {146 .label = "tps65219-gpio",147 .owner = THIS_MODULE,148 .get_direction = tps65219_gpio_get_direction,149 .direction_input = tps65219_gpio_direction_input,150 .direction_output = tps65219_gpio_direction_output,151 .get = tps65219_gpio_get,152 .set = tps65219_gpio_set,153 .base = -1,154 .ngpio = 3,155 .can_sleep = true,156};157 158static int tps65219_gpio_probe(struct platform_device *pdev)159{160 struct tps65219 *tps = dev_get_drvdata(pdev->dev.parent);161 struct tps65219_gpio *gpio;162 163 gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);164 if (!gpio)165 return -ENOMEM;166 167 gpio->tps = tps;168 gpio->gpio_chip = tps65219_template_chip;169 gpio->gpio_chip.parent = tps->dev;170 171 return devm_gpiochip_add_data(&pdev->dev, &gpio->gpio_chip, gpio);172}173 174static struct platform_driver tps65219_gpio_driver = {175 .driver = {176 .name = "tps65219-gpio",177 },178 .probe = tps65219_gpio_probe,179};180module_platform_driver(tps65219_gpio_driver);181 182MODULE_ALIAS("platform:tps65219-gpio");183MODULE_AUTHOR("Jonathan Cormier <jcormier@criticallink.com>");184MODULE_DESCRIPTION("TPS65219 GPIO driver");185MODULE_LICENSE("GPL");186