linux-stable/include/linux/input/gpio_tilt.h
Heiko Stübner 3bfd5c5baf Input: add generic GPIO-tilt driver
There exist tilt switches that simply report their tilt-state via
some gpios. The number and orientation of their axes can vary
depending on the switch used and the build of the device. Also two
or more one-axis switches could be combined to provide multi-dimensional
orientation.

One example of a device using such a switch is the family of Qisda
ebook readers, where the switch provides information about the
landscape / portrait orientation of the device. The example in
Documentation/input/gpio-tilt.txt documents exactly this one-axis
device.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-11-30 23:41:16 -08:00

73 lines
1.9 KiB
C

#ifndef _INPUT_GPIO_TILT_H
#define _INPUT_GPIO_TILT_H
/**
* struct gpio_tilt_axis - Axis used by the tilt switch
* @axis: Constant describing the axis, e.g. ABS_X
* @min: minimum value for abs_param
* @max: maximum value for abs_param
* @fuzz: fuzz value for abs_param
* @flat: flat value for abs_param
*/
struct gpio_tilt_axis {
int axis;
int min;
int max;
int fuzz;
int flat;
};
/**
* struct gpio_tilt_state - state description
* @gpios: bitfield of gpio target-states for the value
* @axes: array containing the axes settings for the gpio state
* The array indizes must correspond to the axes defined
* in platform_data
*
* This structure describes a supported axis settings
* and the necessary gpio-state which represent it.
*
* The n-th bit in the bitfield describes the state of the n-th GPIO
* from the gpios-array defined in gpio_regulator_config below.
*/
struct gpio_tilt_state {
int gpios;
int *axes;
};
/**
* struct gpio_tilt_platform_data
* @gpios: Array containing the gpios determining the tilt state
* @nr_gpios: Number of gpios
* @axes: Array of gpio_tilt_axis descriptions
* @nr_axes: Number of axes
* @states: Array of gpio_tilt_state entries describing
* the gpio state for specific tilts
* @nr_states: Number of states available
* @debounce_interval: debounce ticks interval in msecs
* @poll_interval: polling interval in msecs - for polling driver only
* @enable: callback to enable the tilt switch
* @disable: callback to disable the tilt switch
*
* This structure contains gpio-tilt-switch configuration
* information that must be passed by platform code to the
* gpio-tilt input driver.
*/
struct gpio_tilt_platform_data {
struct gpio *gpios;
int nr_gpios;
struct gpio_tilt_axis *axes;
int nr_axes;
struct gpio_tilt_state *states;
int nr_states;
int debounce_interval;
unsigned int poll_interval;
int (*enable)(struct device *dev);
void (*disable)(struct device *dev);
};
#endif