ugfx/drivers/ginput/touch/STMPE811/ginput_lld_mouse.c

/*
    ChibiOS/GFX - Copyright (C) 2012, 2013
                 Joel Bodenmann aka Tectu <joel@unormal.org>

    This file is part of ChibiOS/GFX.

    ChibiOS/GFX is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    ChibiOS/GFX is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/**
 * @file    drivers/ginput/touch/STMPE811/ginput_lld_mouse.c
 * @brief   GINPUT Touch low level driver source for the STMPE811.
 *
 * @defgroup Mouse Mouse
 * @ingroup GINPUT
 * @{
 */

#include "ch.h"
#include "hal.h"
#include "gfx.h"

#include "stmpe811.h"

#if (GFX_USE_GINPUT && GINPUT_NEED_MOUSE) /*|| defined(__DOXYGEN__)*/

#include "ginput/lld/mouse.h"

#if defined(GINPUT_MOUSE_USE_CUSTOM_BOARD) && GINPUT_MOUSE_USE_CUSTOM_BOARD
	#include "ginput_lld_mouse_board.h"
#elif defined(BOARD_EMBEST_DMSTF4BB)
	#include "ginput_lld_mouse_board_embest_dmstf4bb.h"
#else
	#include "ginput_lld_mouse_board_example.h"
#endif

static coord_t lastx, lasty, lastz;

/* set the active window of the stmpe811. bl is bottom left, tr is top right */
static void setActiveWindow(uint16_t bl_x, uint16_t bl_y, uint16_t tr_x, uint16_t tr_y)
{
	write_reg(STMPE811_REG_WDW_TR_X, 2, tr_x);
	write_reg(STMPE811_REG_WDW_TR_Y, 2, tr_y);
	write_reg(STMPE811_REG_WDW_BL_X, 2, bl_x);
	write_reg(STMPE811_REG_WDW_BL_Y, 2, bl_y);
}

/**
 * @brief   Initialise the mouse/touch.
 *
 * @notapi
 */
void ginput_lld_mouse_init(void)
{
	init_board();

	write_reg(STMPE811_REG_SYS_CTRL1,		1, 0x02);	// Software chip reset
	chThdSleepMilliseconds(10);

	write_reg(STMPE811_REG_SYS_CTRL2,		1, 0x0C);	// Temperature sensor clock off, GPIO clock off, touch clock on, ADC clock on
	write_reg(STMPE811_REG_INT_EN,			1, 0x02);	// Interrupt on INT pin when FIFO is equal or above threshold value OR touch is detected
	write_reg(STMPE811_REG_ADC_CTRL1,		1, 0x48);	// ADC conversion time = 80 clock ticks, 12-bit ADC, internal voltage refernce
	chThdSleepMilliseconds(2);

	write_reg(STMPE811_REG_ADC_CTRL2,		1, 0x01);	// ADC speed 3.25MHz
	write_reg(STMPE811_REG_GPIO_AF,			1, 0x00);	// GPIO alternate function - OFF
	write_reg(STMPE811_REG_TSC_CFG,			1, 0x9A);	// Averaging 4, touch detect delay 500 us, panel driver settling time 500 us
	write_reg(STMPE811_REG_FIFO_TH,			1, 0x01);	// FIFO threshold = 1
	write_reg(STMPE811_REG_FIFO_STA,		1, 0x01);	// FIFO reset enable
	write_reg(STMPE811_REG_FIFO_STA,		1, 0x00);	// FIFO reset disable
	write_reg(STMPE811_REG_TSC_FRACT_XYZ,	1, 0x07);	// Z axis data format
	write_reg(STMPE811_REG_TSC_I_DRIVE,		1, 0x01);	// 50mA touchscreen line current
	write_reg(STMPE811_REG_TSC_CTRL,		1, 0x01);	// X&Y&Z, TSC enable
	write_reg(STMPE811_REG_INT_STA,			1, 0xFF);	// Clear all interrupts
	write_reg(STMPE811_REG_INT_CTRL,		1, 0x01);	// Level interrupt, enable intrrupts
}

/**
 * @brief   Read the mouse/touch position.
 *
 * @param[in] pt	A pointer to the structure to fill
 *
 * @note			For drivers that don't support returning a position
 *					when the touch is up (most touch devices), it should
 *					return the previous position with the new Z value.
 *					The z value is the pressure for those touch devices
 *					that support it (-100 to 100 where > 0 is touched)
 *					or, 0 or 100 for those drivers that don't.
 *
 * @notapi
 */
void ginput_lld_mouse_get_reading(MouseReading *pt)
{
	//uint16_t buf;
	uint8_t int_status;

	// If not touched, return the previous results
	if (!getpin_pressed()) {
		pt->x = lastx;
		pt->y = lasty;
		pt->z = 0;
		pt->buttons = 0;
		return;
	}

	// Find out what caused an interrupt
	int_status = read_reg(STMPE811_REG_INT_STA, 1);

	// If it is TOUCH interrupt, clear it and go on
	if (int_status & 0x02) {

		uint8_t size = 0;
		size = read_reg(STMPE811_REG_FIFO_SIZE, 1);

		if (size) {
			uint8_t buffer[size * 4];
			read_reg_n(STMPE811_REG_TSC_DATA_AI, size * 4, buffer);

			lastx = (coord_t)((buffer[0] << 4) | (buffer[1] >> 4));
			lasty = (coord_t)(((buffer[1] & 0x0F) << 8) | buffer[2]);
			lastz = (coord_t)buffer[3];

			/* Get the X value */
			//buf = read_reg(STMPE811_REG_TSC_DATA_X, 2);
			//lastx = (coord_t)(buf);

			/* Get the Y value */
			//buf = read_reg(STMPE811_REG_TSC_DATA_Y, 2);
			//lasty = (coord_t)(buf);

			/* Get the Z value */
			//buf = read_reg(STMPE811_REG_TSC_DATA_Z, 1);
			//lastz = (buf & 0x00FF);

			// Return the results. ADC gives values from 0 to 2^12
			pt->x = 320 - lastx / 13;
			pt->y = lasty / 17;
			pt->z = lastz;
			pt->buttons = GINPUT_TOUCH_PRESSED;
		}

		write_reg(STMPE811_REG_INT_STA, 1, 0x02);
	}
}

#endif /* GFX_USE_GINPUT && GINPUT_NEED_MOUSE */
/** @} */