From f8ec92a9f63b3b11e399409141b7868bb405e6b5 Mon Sep 17 00:00:00 2001 From: Ricardo Ribalda Delgado Date: Fri, 5 Oct 2018 08:52:58 +0200 Subject: [PATCH] gpiolib: Add init_valid_mask exported function Add a function that allows initializing the valid_mask from gpiochip_add_data. This prevents race conditions during gpiochip initialization. If the function is not exported, then the old behaviour is respected, this is, set all gpios as valid. Signed-off-by: Ricardo Ribalda Delgado Tested-by: Jeffrey Hugo Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib.c | 16 ++++++++++++++-- include/linux/gpio/driver.h | 7 ++++++- 2 files changed, 20 insertions(+), 3 deletions(-) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 02660bf..b66aae7 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -360,7 +360,7 @@ static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip) return p; } -static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip) +static int gpiochip_alloc_valid_mask(struct gpio_chip *gpiochip) { #ifdef CONFIG_OF_GPIO int size; @@ -381,6 +381,14 @@ static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip) return 0; } +static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip) +{ + if (gpiochip->init_valid_mask) + return gpiochip->init_valid_mask(gpiochip); + + return 0; +} + static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip) { kfree(gpiochip->valid_mask); @@ -1369,7 +1377,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data, if (status) goto err_remove_from_list; - status = gpiochip_init_valid_mask(chip); + status = gpiochip_alloc_valid_mask(chip); if (status) goto err_remove_irqchip_mask; @@ -1381,6 +1389,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data, if (status) goto err_remove_chip; + status = gpiochip_init_valid_mask(chip); + if (status) + goto err_remove_chip; + acpi_gpiochip_add(chip); machine_gpiochip_add(chip); diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index f6b9573..c5a51af 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -280,6 +280,9 @@ struct gpio_chip { void (*dbg_show)(struct seq_file *s, struct gpio_chip *chip); + + int (*init_valid_mask)(struct gpio_chip *chip); + int base; u16 ngpio; const char *const *names; @@ -318,7 +321,9 @@ struct gpio_chip { /** * @need_valid_mask: * - * If set core allocates @valid_mask with all bits set to one. + * If set core allocates @valid_mask with all its values initialized + * with init_valid_mask() or set to one if init_valid_mask() is not + * defined */ bool need_valid_mask; -- 2.7.4