STMPE811 Touchscreen Controller

Device driver interface for the STMPE811 touchscreen controller. More...

Detailed Description

Device driver interface for the STMPE811 touchscreen controller.

Files
file	stmpe811.h
file	stmpe811_constants.h
	Constants for STMPE811.
file	stmpe811_params.h
	Default configuration for STMPE811.
file	stmpe811_touch_dev.h
	Definition of the driver for the touch_dev generic interface.

Data Structures
struct	stmpe811_touch_position_t
	Touch position structure. More...
struct	stmpe811_params_t
	Device initialization parameters. More...
struct	stmpe811_t
	Device descriptor for the STMPE811 sensor. More...

Typedefs
typedef void(*	stmpe811_event_cb_t) (void *arg)
	Signature of touch event callback triggered from interrupt.

Enumerations
enum	stmpe811_touch_state_t { STMPE811_TOUCH_STATE_PRESSED , STMPE811_TOUCH_STATE_RELEASED }
	Touch state enum. More...
enum	stmpe811_touch_conv_t { STMPE811_NO_CONV = 0x00 , STMPE811_MIRROR_X = 0x01 , STMPE811_MIRROR_Y = 0x02 , STMPE811_SWAP_XY = 0x04 }
	Touch screen coordinate conversions. More...

Functions
int	stmpe811_init (stmpe811_t *dev, const stmpe811_params_t *params, stmpe811_event_cb_t cb, void *arg)
	Initialize the given STMPE811 device.
int	stmpe811_read_touch_position (stmpe811_t *dev, stmpe811_touch_position_t *position)
	Read the touch position.
int	stmpe811_read_touch_state (const stmpe811_t *dev, stmpe811_touch_state_t *state)
	Read the touch state (pressed or released)

Typedef Documentation

stmpe811_event_cb_t

typedef void(* stmpe811_event_cb_t) (void *arg)

Signature of touch event callback triggered from interrupt.

Parameters

[in]

arg

optional context for the callback

Definition at line 81 of file stmpe811.h.

Enumeration Type Documentation

stmpe811_touch_conv_t

enum stmpe811_touch_conv_t

Touch screen coordinate conversions.

Normally the coordinates of the touch device must be converted to the screen coordinates by swapping and/or mirroring. The flags defined by this enumeration can be ORed for a combined conversion. In this case, the swapping is performed before the mirroring.

Note

The maximum X and Y screen coordinates defined by stmpe811_params_t::xmax and stmpe811_params_t::ymax define the dimension of the touch device in screen coordinates, i.e. after conversion.

Enumerator
STMPE811_NO_CONV	No conversion.
STMPE811_MIRROR_X	Mirror X, applied after optional swapping.
STMPE811_MIRROR_Y	Mirror Y, applied after optional swapping.
STMPE811_SWAP_XY	Swap XY, applied before optional mirroring.

Definition at line 61 of file stmpe811.h.

stmpe811_touch_state_t

enum stmpe811_touch_state_t

Touch state enum.

Enumerator
STMPE811_TOUCH_STATE_PRESSED	Touchscreen is pressed.
STMPE811_TOUCH_STATE_RELEASED	Touchscreen is released.

Definition at line 43 of file stmpe811.h.

Function Documentation

stmpe811_init()

int stmpe811_init	(	stmpe811_t *	dev,
		const stmpe811_params_t *	params,
		stmpe811_event_cb_t	cb,
		void *	arg
	)

Initialize the given STMPE811 device.

Parameters

[in,out]	dev	Device descriptor of the STMPE811
[in]	params	Initialization parameters of the STMPE811 device
[in]	cb	Callback function called on touch interrupts
[in]	arg	Context argument used in callback function

Returns

0 on success

-ENODEV when no valid device

-EIO when software reset failed

-EPROTO on any bus error

stmpe811_read_touch_position()

int stmpe811_read_touch_position	(	stmpe811_t *	dev,
		stmpe811_touch_position_t *	position
	)

Read the touch position.

Parameters

[in]	dev	Device descriptor of the STMPE811
[out]	position	Touch position

Returns

0 on success

-EPROTO on any bus error

stmpe811_read_touch_state()

int stmpe811_read_touch_state	(	const stmpe811_t *	dev,
		stmpe811_touch_state_t *	state
	)

Read the touch state (pressed or released)

Parameters

[in]	dev	Device descriptor of the STMPE811
[out]	state	Touch state

Returns

0 on success

-EPROTO on any busI2aC error