Reading & setting line values

Collaboration diagram for Reading & setting line values:

Functions
int	gpiod_line_get_value (struct gpiod_line *line) GPIOD_API
	Read current value of a single GPIO line. More...
int	gpiod_line_get_value_bulk (struct gpiod_line_bulk *bulk, int *values) GPIOD_API
	Read current values of a set of GPIO lines. More...
int	gpiod_line_set_value (struct gpiod_line *line, int value) GPIOD_API
	Set the value of a single GPIO line. More...
int	gpiod_line_set_value_bulk (struct gpiod_line_bulk *bulk, const int *values) GPIOD_API
	Set the values of a set of GPIO lines. More...

Detailed Description

Function Documentation

gpiod_line_get_value()

int gpiod_line_get_value

(

struct gpiod_line *

line

)

Read current value of a single GPIO line.

Parameters

line	GPIO line object.

Returns

0 or 1 if the operation succeeds. On error this routine returns -1 and sets the last error number.

gpiod_line_get_value_bulk()

int gpiod_line_get_value_bulk	(	struct gpiod_line_bulk *	bulk,
		int *	values
	)

Read current values of a set of GPIO lines.

Parameters

bulk	Set of GPIO lines to reserve.
values	An array big enough to hold line_bulk->num_lines values.

Returns

0 is the operation succeeds. In case of an error this routine returns -1 and sets the last error number.

If succeeds, this routine fills the values array with a set of values in the same order, the lines are added to line_bulk. If the lines were not previously requested together, the behavior is undefined.

gpiod_line_set_value()

int gpiod_line_set_value	(	struct gpiod_line *	line,
		int	value
	)

Set the value of a single GPIO line.

Parameters

line	GPIO line object.
value	New value.

Returns

0 is the operation succeeds. In case of an error this routine returns -1 and sets the last error number.

gpiod_line_set_value_bulk()

int gpiod_line_set_value_bulk	(	struct gpiod_line_bulk *	bulk,
		const int *	values
	)

Set the values of a set of GPIO lines.

Parameters

bulk	Set of GPIO lines to reserve.
values	An array holding line_bulk->num_lines new values for lines.

Returns

0 is the operation succeeds. In case of an error this routine returns -1 and sets the last error number.

If the lines were not previously requested together, the behavior is undefined.