linux/drivers/gpio/gpio-max77620.c
Timo Alho ab3dd9cc24 gpio: max77620: Fix interrupt handling
The interrupt-related register fields on the MAX77620 GPIO controller
share registers with GPIO related fields. If the IRQ chip is implemented
with regmap-irq, this causes the IRQ controller code to overwrite fields
previously configured by the GPIO controller code.

Two examples where this causes problems are the NVIDIA Jetson TX1 and
Jetson TX2 boards, where some of the GPIOs are used to enable vital
power regulators. The MAX77620 GPIO controller also provides the USB OTG
ID pin. If configured as an interrupt, this causes some of the
regulators to be powered off.

Signed-off-by: Timo Alho <talho@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20191002122825.3948322-3-thierry.reding@gmail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-10-05 00:01:54 +02:00

341 lines
8.7 KiB
C

// 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[8];
bool irq_enabled[8];
};
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, 8) {
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;
}
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);
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 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_MASK_ON_SUSPEND,
};
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 ... 8:
val = MAX77620_CNFG_GPIO_DBNC_8ms;
break;
case 9 ... 16:
val = MAX77620_CNFG_GPIO_DBNC_16ms;
break;
case 17 ... 32:
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_probe(struct platform_device *pdev)
{
struct max77620_chip *chip = dev_get_drvdata(pdev->dev.parent);
struct max77620_gpio *mgpio;
int gpio_irq;
int ret;
gpio_irq = platform_get_irq(pdev, 0);
if (gpio_irq <= 0)
return -ENODEV;
mgpio = devm_kzalloc(&pdev->dev, sizeof(*mgpio), GFP_KERNEL);
if (!mgpio)
return -ENOMEM;
mgpio->rmap = chip->rmap;
mgpio->dev = &pdev->dev;
mgpio->gpio_chip.label = pdev->name;
mgpio->gpio_chip.parent = &pdev->dev;
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;
#ifdef CONFIG_OF_GPIO
mgpio->gpio_chip.of_node = pdev->dev.parent->of_node;
#endif
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;
}
mutex_init(&mgpio->buslock);
gpiochip_irqchip_add_nested(&mgpio->gpio_chip, &max77620_gpio_irqchip,
0, handle_edge_irq, IRQ_TYPE_NONE);
ret = request_threaded_irq(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;
}
gpiochip_set_nested_irqchip(&mgpio->gpio_chip, &max77620_gpio_irqchip,
gpio_irq);
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_ALIAS("platform:max77620-gpio");
MODULE_LICENSE("GPL v2");