linux/drivers/gpio/gpio-wcd934x.c
Srinivas Kandagatla dbec64b11c gpio: wcd934x: Fix shift-out-of-bounds error
bit-mask for pins 0 to 4 is BIT(0) to BIT(4) however we ended up with BIT(n - 1)
which is not right, and this was caught by below usban check

UBSAN: shift-out-of-bounds in drivers/gpio/gpio-wcd934x.c:34:14

Fixes: 59c3246834 ("gpio: wcd934x: Add support to wcd934x gpio controller")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2021-05-27 09:51:35 +02:00

125 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019, Linaro Limited
#include <linux/module.h>
#include <linux/gpio/driver.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/of_device.h>
#define WCD_PIN_MASK(p) BIT(p)
#define WCD_REG_DIR_CTL_OFFSET 0x42
#define WCD_REG_VAL_CTL_OFFSET 0x43
#define WCD934X_NPINS 5
struct wcd_gpio_data {
struct regmap *map;
struct gpio_chip chip;
};
static int wcd_gpio_get_direction(struct gpio_chip *chip, unsigned int pin)
{
struct wcd_gpio_data *data = gpiochip_get_data(chip);
unsigned int value;
int ret;
ret = regmap_read(data->map, WCD_REG_DIR_CTL_OFFSET, &value);
if (ret < 0)
return ret;
if (value & WCD_PIN_MASK(pin))
return GPIO_LINE_DIRECTION_OUT;
return GPIO_LINE_DIRECTION_IN;
}
static int wcd_gpio_direction_input(struct gpio_chip *chip, unsigned int pin)
{
struct wcd_gpio_data *data = gpiochip_get_data(chip);
return regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET,
WCD_PIN_MASK(pin), 0);
}
static int wcd_gpio_direction_output(struct gpio_chip *chip, unsigned int pin,
int val)
{
struct wcd_gpio_data *data = gpiochip_get_data(chip);
regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET,
WCD_PIN_MASK(pin), WCD_PIN_MASK(pin));
return regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
WCD_PIN_MASK(pin),
val ? WCD_PIN_MASK(pin) : 0);
}
static int wcd_gpio_get(struct gpio_chip *chip, unsigned int pin)
{
struct wcd_gpio_data *data = gpiochip_get_data(chip);
unsigned int value;
regmap_read(data->map, WCD_REG_VAL_CTL_OFFSET, &value);
return !!(value & WCD_PIN_MASK(pin));
}
static void wcd_gpio_set(struct gpio_chip *chip, unsigned int pin, int val)
{
struct wcd_gpio_data *data = gpiochip_get_data(chip);
regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
WCD_PIN_MASK(pin), val ? WCD_PIN_MASK(pin) : 0);
}
static int wcd_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct wcd_gpio_data *data;
struct gpio_chip *chip;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->map = dev_get_regmap(dev->parent, NULL);
if (!data->map) {
dev_err(dev, "%s: failed to get regmap\n", __func__);
return -EINVAL;
}
chip = &data->chip;
chip->direction_input = wcd_gpio_direction_input;
chip->direction_output = wcd_gpio_direction_output;
chip->get_direction = wcd_gpio_get_direction;
chip->get = wcd_gpio_get;
chip->set = wcd_gpio_set;
chip->parent = dev;
chip->base = -1;
chip->ngpio = WCD934X_NPINS;
chip->label = dev_name(dev);
chip->of_gpio_n_cells = 2;
chip->can_sleep = false;
return devm_gpiochip_add_data(dev, chip, data);
}
static const struct of_device_id wcd_gpio_of_match[] = {
{ .compatible = "qcom,wcd9340-gpio" },
{ .compatible = "qcom,wcd9341-gpio" },
{ }
};
MODULE_DEVICE_TABLE(of, wcd_gpio_of_match);
static struct platform_driver wcd_gpio_driver = {
.driver = {
.name = "wcd934x-gpio",
.of_match_table = wcd_gpio_of_match,
},
.probe = wcd_gpio_probe,
};
module_platform_driver(wcd_gpio_driver);
MODULE_DESCRIPTION("Qualcomm Technologies, Inc WCD GPIO control driver");
MODULE_LICENSE("GPL v2");