Commit 2821ae5f authored by Kent Gibson's avatar Kent Gibson Committed by Bartosz Golaszewski
Browse files

gpiolib: add support for biasing output lines 



Allow pull up/down bias to be set on output lines.
Use case is for open source or open drain applications where
internal pull up/down may conflict with external biasing.

Signed-off-by: default avatarKent Gibson <warthog618@gmail.com>
Signed-off-by: default avatarBartosz Golaszewski <bgolaszewski@baylibre.com>
parent 2148ad77

drivers/gpio/gpiolib.c

+6 −2
Original line number Original line Diff line number Diff line
@@ -556,8 +556,9 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip) 
	     (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))

	     (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))

		return -EINVAL;

		return -EINVAL;





	/* Bias flags only allowed for input mode. */

	/* Bias flags only allowed for input or output mode. */

	if (!(lflags & GPIOHANDLE_REQUEST_INPUT) &&

	if (!((lflags & GPIOHANDLE_REQUEST_INPUT) ||

	      (lflags & GPIOHANDLE_REQUEST_OUTPUT)) &&

	    ((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) ||

	    ((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) ||

	     (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) ||

	     (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) ||

	     (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)))

	     (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)))
@@ -3169,6 +3170,9 @@ int gpiod_direction_output(struct gpio_desc *desc, int value) 
	}

	}





set_output_value:

set_output_value:

	ret = gpio_set_bias(gc, desc);

	if (ret)

		return ret;

	return gpiod_direction_output_raw_commit(desc, value);

	return gpiod_direction_output_raw_commit(desc, value);





set_output_flag:

set_output_flag:

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