diff options
Diffstat (limited to 'drivers/gpio/gpio-max77620.c')
| -rw-r--r-- | drivers/gpio/gpio-max77620.c | 371 |
1 files changed, 371 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-max77620.c b/drivers/gpio/gpio-max77620.c new file mode 100644 index 000000000..c18b60e39 --- /dev/null +++ b/drivers/gpio/gpio-max77620.c @@ -0,0 +1,371 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * MAXIM MAX77620 GPIO driver + * + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. + */ + +#include <linux/gpio/driver.h> +#include <linux/interrupt.h> +#include <linux/mfd/max77620.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +#define GPIO_REG_ADDR(offset) (MAX77620_REG_GPIO0 + offset) + +struct max77620_gpio { + struct gpio_chip gpio_chip; + struct regmap *rmap; + struct device *dev; + struct mutex buslock; /* irq_bus_lock */ + unsigned int irq_type[MAX77620_GPIO_NR]; + bool irq_enabled[MAX77620_GPIO_NR]; +}; + +static irqreturn_t max77620_gpio_irqhandler(int irq, void *data) +{ + struct max77620_gpio *gpio = data; + unsigned int value, offset; + unsigned long pending; + int err; + + err = regmap_read(gpio->rmap, MAX77620_REG_IRQ_LVL2_GPIO, &value); + if (err < 0) { + dev_err(gpio->dev, "REG_IRQ_LVL2_GPIO read failed: %d\n", err); + return IRQ_NONE; + } + + pending = value; + + for_each_set_bit(offset, &pending, MAX77620_GPIO_NR) { + unsigned int virq; + + virq = irq_find_mapping(gpio->gpio_chip.irq.domain, offset); + handle_nested_irq(virq); + } + + return IRQ_HANDLED; +} + +static void max77620_gpio_irq_mask(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct max77620_gpio *gpio = gpiochip_get_data(chip); + + gpio->irq_enabled[data->hwirq] = false; + gpiochip_disable_irq(chip, data->hwirq); +} + +static void max77620_gpio_irq_unmask(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct max77620_gpio *gpio = gpiochip_get_data(chip); + + gpiochip_enable_irq(chip, data->hwirq); + gpio->irq_enabled[data->hwirq] = true; +} + +static int max77620_gpio_set_irq_type(struct irq_data *data, unsigned int type) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct max77620_gpio *gpio = gpiochip_get_data(chip); + unsigned int irq_type; + + switch (type) { + case IRQ_TYPE_EDGE_RISING: + irq_type = MAX77620_CNFG_GPIO_INT_RISING; + break; + + case IRQ_TYPE_EDGE_FALLING: + irq_type = MAX77620_CNFG_GPIO_INT_FALLING; + break; + + case IRQ_TYPE_EDGE_BOTH: + irq_type = MAX77620_CNFG_GPIO_INT_RISING | + MAX77620_CNFG_GPIO_INT_FALLING; + break; + + default: + return -EINVAL; + } + + gpio->irq_type[data->hwirq] = irq_type; + + return 0; +} + +static void max77620_gpio_bus_lock(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct max77620_gpio *gpio = gpiochip_get_data(chip); + + mutex_lock(&gpio->buslock); +} + +static void max77620_gpio_bus_sync_unlock(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct max77620_gpio *gpio = gpiochip_get_data(chip); + unsigned int value, offset = data->hwirq; + int err; + + value = gpio->irq_enabled[offset] ? gpio->irq_type[offset] : 0; + + err = regmap_update_bits(gpio->rmap, GPIO_REG_ADDR(offset), + MAX77620_CNFG_GPIO_INT_MASK, value); + if (err < 0) + dev_err(chip->parent, "failed to update interrupt mask: %d\n", + err); + + mutex_unlock(&gpio->buslock); +} + +static const struct irq_chip max77620_gpio_irqchip = { + .name = "max77620-gpio", + .irq_mask = max77620_gpio_irq_mask, + .irq_unmask = max77620_gpio_irq_unmask, + .irq_set_type = max77620_gpio_set_irq_type, + .irq_bus_lock = max77620_gpio_bus_lock, + .irq_bus_sync_unlock = max77620_gpio_bus_sync_unlock, + .flags = IRQCHIP_IMMUTABLE | IRQCHIP_MASK_ON_SUSPEND, + GPIOCHIP_IRQ_RESOURCE_HELPERS, +}; + +static int max77620_gpio_dir_input(struct gpio_chip *gc, unsigned int offset) +{ + struct max77620_gpio *mgpio = gpiochip_get_data(gc); + int ret; + + ret = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), + MAX77620_CNFG_GPIO_DIR_MASK, + MAX77620_CNFG_GPIO_DIR_INPUT); + if (ret < 0) + dev_err(mgpio->dev, "CNFG_GPIOx dir update failed: %d\n", ret); + + return ret; +} + +static int max77620_gpio_get(struct gpio_chip *gc, unsigned int offset) +{ + struct max77620_gpio *mgpio = gpiochip_get_data(gc); + unsigned int val; + int ret; + + ret = regmap_read(mgpio->rmap, GPIO_REG_ADDR(offset), &val); + if (ret < 0) { + dev_err(mgpio->dev, "CNFG_GPIOx read failed: %d\n", ret); + return ret; + } + + if (val & MAX77620_CNFG_GPIO_DIR_MASK) + return !!(val & MAX77620_CNFG_GPIO_INPUT_VAL_MASK); + else + return !!(val & MAX77620_CNFG_GPIO_OUTPUT_VAL_MASK); +} + +static int max77620_gpio_dir_output(struct gpio_chip *gc, unsigned int offset, + int value) +{ + struct max77620_gpio *mgpio = gpiochip_get_data(gc); + u8 val; + int ret; + + val = (value) ? MAX77620_CNFG_GPIO_OUTPUT_VAL_HIGH : + MAX77620_CNFG_GPIO_OUTPUT_VAL_LOW; + + ret = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), + MAX77620_CNFG_GPIO_OUTPUT_VAL_MASK, val); + if (ret < 0) { + dev_err(mgpio->dev, "CNFG_GPIOx val update failed: %d\n", ret); + return ret; + } + + ret = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), + MAX77620_CNFG_GPIO_DIR_MASK, + MAX77620_CNFG_GPIO_DIR_OUTPUT); + if (ret < 0) + dev_err(mgpio->dev, "CNFG_GPIOx dir update failed: %d\n", ret); + + return ret; +} + +static int max77620_gpio_set_debounce(struct max77620_gpio *mgpio, + unsigned int offset, + unsigned int debounce) +{ + u8 val; + int ret; + + switch (debounce) { + case 0: + val = MAX77620_CNFG_GPIO_DBNC_None; + break; + case 1 ... 8000: + val = MAX77620_CNFG_GPIO_DBNC_8ms; + break; + case 8001 ... 16000: + val = MAX77620_CNFG_GPIO_DBNC_16ms; + break; + case 16001 ... 32000: + val = MAX77620_CNFG_GPIO_DBNC_32ms; + break; + default: + dev_err(mgpio->dev, "Illegal value %u\n", debounce); + return -EINVAL; + } + + ret = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), + MAX77620_CNFG_GPIO_DBNC_MASK, val); + if (ret < 0) + dev_err(mgpio->dev, "CNFG_GPIOx_DBNC update failed: %d\n", ret); + + return ret; +} + +static void max77620_gpio_set(struct gpio_chip *gc, unsigned int offset, + int value) +{ + struct max77620_gpio *mgpio = gpiochip_get_data(gc); + u8 val; + int ret; + + val = (value) ? MAX77620_CNFG_GPIO_OUTPUT_VAL_HIGH : + MAX77620_CNFG_GPIO_OUTPUT_VAL_LOW; + + ret = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), + MAX77620_CNFG_GPIO_OUTPUT_VAL_MASK, val); + if (ret < 0) + dev_err(mgpio->dev, "CNFG_GPIO_OUT update failed: %d\n", ret); +} + +static int max77620_gpio_set_config(struct gpio_chip *gc, unsigned int offset, + unsigned long config) +{ + struct max77620_gpio *mgpio = gpiochip_get_data(gc); + + switch (pinconf_to_config_param(config)) { + case PIN_CONFIG_DRIVE_OPEN_DRAIN: + return regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), + MAX77620_CNFG_GPIO_DRV_MASK, + MAX77620_CNFG_GPIO_DRV_OPENDRAIN); + case PIN_CONFIG_DRIVE_PUSH_PULL: + return regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), + MAX77620_CNFG_GPIO_DRV_MASK, + MAX77620_CNFG_GPIO_DRV_PUSHPULL); + case PIN_CONFIG_INPUT_DEBOUNCE: + return max77620_gpio_set_debounce(mgpio, offset, + pinconf_to_config_argument(config)); + default: + break; + } + + return -ENOTSUPP; +} + +static int max77620_gpio_irq_init_hw(struct gpio_chip *gc) +{ + struct max77620_gpio *gpio = gpiochip_get_data(gc); + unsigned int i; + int err; + + /* + * GPIO interrupts may be left ON after bootloader, hence let's + * pre-initialize hardware to the expected state by disabling all + * the interrupts. + */ + for (i = 0; i < MAX77620_GPIO_NR; i++) { + err = regmap_update_bits(gpio->rmap, GPIO_REG_ADDR(i), + MAX77620_CNFG_GPIO_INT_MASK, 0); + if (err < 0) { + dev_err(gpio->dev, + "failed to disable interrupt: %d\n", err); + return err; + } + } + + return 0; +} + +static int max77620_gpio_probe(struct platform_device *pdev) +{ + struct max77620_chip *chip = dev_get_drvdata(pdev->dev.parent); + struct max77620_gpio *mgpio; + struct gpio_irq_chip *girq; + unsigned int gpio_irq; + int ret; + + ret = platform_get_irq(pdev, 0); + if (ret < 0) + return ret; + + gpio_irq = ret; + + mgpio = devm_kzalloc(&pdev->dev, sizeof(*mgpio), GFP_KERNEL); + if (!mgpio) + return -ENOMEM; + + mutex_init(&mgpio->buslock); + mgpio->rmap = chip->rmap; + mgpio->dev = &pdev->dev; + + mgpio->gpio_chip.label = pdev->name; + mgpio->gpio_chip.parent = pdev->dev.parent; + mgpio->gpio_chip.direction_input = max77620_gpio_dir_input; + mgpio->gpio_chip.get = max77620_gpio_get; + mgpio->gpio_chip.direction_output = max77620_gpio_dir_output; + mgpio->gpio_chip.set = max77620_gpio_set; + mgpio->gpio_chip.set_config = max77620_gpio_set_config; + mgpio->gpio_chip.ngpio = MAX77620_GPIO_NR; + mgpio->gpio_chip.can_sleep = 1; + mgpio->gpio_chip.base = -1; + + girq = &mgpio->gpio_chip.irq; + gpio_irq_chip_set_chip(girq, &max77620_gpio_irqchip); + /* This will let us handle the parent IRQ in the driver */ + girq->parent_handler = NULL; + girq->num_parents = 0; + girq->parents = NULL; + girq->default_type = IRQ_TYPE_NONE; + girq->handler = handle_edge_irq; + girq->init_hw = max77620_gpio_irq_init_hw; + girq->threaded = true; + + platform_set_drvdata(pdev, mgpio); + + ret = devm_gpiochip_add_data(&pdev->dev, &mgpio->gpio_chip, mgpio); + if (ret < 0) { + dev_err(&pdev->dev, "gpio_init: Failed to add max77620_gpio\n"); + return ret; + } + + ret = devm_request_threaded_irq(&pdev->dev, gpio_irq, NULL, + max77620_gpio_irqhandler, IRQF_ONESHOT, + "max77620-gpio", mgpio); + if (ret < 0) { + dev_err(&pdev->dev, "failed to request IRQ: %d\n", ret); + return ret; + } + + return 0; +} + +static const struct platform_device_id max77620_gpio_devtype[] = { + { .name = "max77620-gpio", }, + { .name = "max20024-gpio", }, + {}, +}; +MODULE_DEVICE_TABLE(platform, max77620_gpio_devtype); + +static struct platform_driver max77620_gpio_driver = { + .driver.name = "max77620-gpio", + .probe = max77620_gpio_probe, + .id_table = max77620_gpio_devtype, +}; + +module_platform_driver(max77620_gpio_driver); + +MODULE_DESCRIPTION("GPIO interface for MAX77620 and MAX20024 PMIC"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); +MODULE_AUTHOR("Chaitanya Bandi <bandik@nvidia.com>"); +MODULE_LICENSE("GPL v2"); |