diff options
-rw-r--r-- | Documentation/gpio/00-INDEX | 14 | ||||
-rw-r--r-- | drivers/gpio/gpio-mpc8xxx.c | 8 | ||||
-rw-r--r-- | drivers/gpio/gpiolib.c | 20 | ||||
-rw-r--r-- | include/linux/gpio/driver.h | 3 |
4 files changed, 38 insertions, 7 deletions
diff --git a/Documentation/gpio/00-INDEX b/Documentation/gpio/00-INDEX new file mode 100644 index 000000000000..1de43ae46ae6 --- /dev/null +++ b/Documentation/gpio/00-INDEX @@ -0,0 +1,14 @@ +00-INDEX + - This file +gpio.txt + - Introduction to GPIOs and their kernel interfaces +consumer.txt + - How to obtain and use GPIOs in a driver +driver.txt + - How to write a GPIO driver +board.txt + - How to assign GPIOs to a consumer device and a function +sysfs.txt + - Information about the GPIO sysfs interface +gpio-legacy.txt + - Historical documentation of the deprecated GPIO integer interface diff --git a/drivers/gpio/gpio-mpc8xxx.c b/drivers/gpio/gpio-mpc8xxx.c index 914e859e3eda..d7d6d72eba33 100644 --- a/drivers/gpio/gpio-mpc8xxx.c +++ b/drivers/gpio/gpio-mpc8xxx.c @@ -70,10 +70,14 @@ static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio) u32 val; struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc); struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm); + u32 out_mask, out_shadow; - val = in_be32(mm->regs + GPIO_DAT) & ~in_be32(mm->regs + GPIO_DIR); + out_mask = in_be32(mm->regs + GPIO_DIR); - return (val | mpc8xxx_gc->data) & mpc8xxx_gpio2mask(gpio); + val = in_be32(mm->regs + GPIO_DAT) & ~out_mask; + out_shadow = mpc8xxx_gc->data & out_mask; + + return (val | out_shadow) & mpc8xxx_gpio2mask(gpio); } static int mpc8xxx_gpio_get(struct gpio_chip *gc, unsigned int gpio) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index ac53a9593662..85f772c0b26a 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -2368,7 +2368,7 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, continue; } - if (chip->ngpio >= p->chip_hwnum) { + if (chip->ngpio <= p->chip_hwnum) { dev_warn(dev, "GPIO chip %s has %d GPIOs\n", chip->label, chip->ngpio); continue; @@ -2418,7 +2418,7 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev, const char *con_id, unsigned int idx) { - struct gpio_desc *desc; + struct gpio_desc *desc = NULL; int status; enum gpio_lookup_flags flags = 0; @@ -2431,13 +2431,23 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev, } else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) { dev_dbg(dev, "using ACPI for GPIO lookup\n"); desc = acpi_find_gpio(dev, con_id, idx, &flags); - } else { + } + + /* + * Either we are not using DT or ACPI, or their lookup did not return + * a result. In that case, use platform lookup as a fallback. + */ + if (!desc || IS_ERR(desc)) { + struct gpio_desc *pdesc; dev_dbg(dev, "using lookup tables for GPIO lookup"); - desc = gpiod_find(dev, con_id, idx, &flags); + pdesc = gpiod_find(dev, con_id, idx, &flags); + /* If used as fallback, do not replace the previous error */ + if (!IS_ERR(pdesc) || !desc) + desc = pdesc; } if (IS_ERR(desc)) { - dev_warn(dev, "lookup for GPIO %s failed\n", con_id); + dev_dbg(dev, "lookup for GPIO %s failed\n", con_id); return desc; } diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index 82eac610ce1a..3ea2cf6b0e6c 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -2,9 +2,12 @@ #define __LINUX_GPIO_DRIVER_H #include <linux/types.h> +#include <linux/module.h> struct device; struct gpio_desc; +struct of_phandle_args; +struct device_node; struct seq_file; /** |