[PATCH v4 1/9] gpio: mmio: add BGPIOF_NO_INPUT flag for GPO gpiochip
From: Clément Le Goffic <hidden>
Date: 2025-05-28 13:33:18
Also in:
linux-devicetree, linux-gpio, lkml
Subsystem:
gpio subsystem, the rest · Maintainers:
Linus Walleij, Bartosz Golaszewski, Linus Torvalds
When using bgpio_init with a gpiochip acting as a GPO (output only), the gpiochip ops `direction_input` was set to `bgpio_simple_dir_in` by default but we have no input ability. Adding this flag allows to set a valid ops for the `direction_output` ops without setting a valid ops for `direction_input` by default. Signed-off-by: Clément Le Goffic <redacted> --- drivers/gpio/gpio-mmio.c | 11 ++++++++++- include/linux/gpio/driver.h | 1 + 2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/gpio-mmio.c b/drivers/gpio/gpio-mmio.c
index 4841e4ebe7a6..09b9e1275e7e 100644
--- a/drivers/gpio/gpio-mmio.c
+++ b/drivers/gpio/gpio-mmio.c@@ -335,6 +335,11 @@ static int bgpio_dir_return(struct gpio_chip *gc, unsigned int gpio, bool dir_ou return pinctrl_gpio_direction_input(gc, gpio); } +static int bgpio_dir_in_err(struct gpio_chip *gc, unsigned int gpio) +{ + return -EINVAL; +} + static int bgpio_simple_dir_in(struct gpio_chip *gc, unsigned int gpio) { return bgpio_dir_return(gc, gpio, false);
@@ -566,7 +571,11 @@ static int bgpio_setup_direction(struct gpio_chip *gc, gc->direction_output = bgpio_dir_out_err; else gc->direction_output = bgpio_simple_dir_out; - gc->direction_input = bgpio_simple_dir_in; + + if (flags & BGPIOF_NO_INPUT) + gc->direction_input = bgpio_dir_in_err; + else + gc->direction_input = bgpio_simple_dir_in; } return 0;
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 4c0294a9104d..42890db9b10e 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h@@ -749,6 +749,7 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev, #define BGPIOF_NO_OUTPUT BIT(5) /* only input */ #define BGPIOF_NO_SET_ON_INPUT BIT(6) #define BGPIOF_PINCTRL_BACKEND BIT(7) /* Call pinctrl direction setters */ +#define BGPIOF_NO_INPUT BIT(8) /* only output */ #ifdef CONFIG_GPIOLIB_IRQCHIP int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
--
2.43.0