added touchscreen files

This commit is contained in:
Joel Bodenmann 2012-11-10 00:13:42 +01:00
parent 8f31c5e632
commit affd9792ff
4 changed files with 655 additions and 0 deletions

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/*
ChibiOS/GFX - Copyright (C) 2012
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/>.
*/
/**
* @addtogroup TOUCHSCREEN
* @details The TOUCHSCREEN module provides high level abstraction to interface
* touchscreens.
*/

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/*
ChibiOS/GFX - Copyright (C) 2012
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 include/touchscreen.h
* @brief TOUCHSCREEN Touchscreen driver subsystem header file.
*
* @addtogroup TOUCHSCREEN
* @{
*/
#ifndef TOUCHSCREEN_H
#define TOUCHSCREEN_H
#if GFX_USE_TOUCHSCREEN || defined(__DOXYGEN__)
/**
* @brief specifies how many conversions are made for a readout.
*
* @note higher is more accurate, but takes more time
*/
#define CONVERSIONS 3
/*===========================================================================*/
/* Driver constants. */
/*===========================================================================*/
/*===========================================================================*/
/* Low Level Driver details and error checks. */
/*===========================================================================*/
/* Include the low level driver information */
#include "touchscreen_lld.h"
/* For definitions of coord_t, we require gdisp.h */
#include "gdisp.h"
/*===========================================================================*/
/* Type definitions */
/*===========================================================================*/
/**
* @brief Struct used for calibration
*/
typedef struct cal_t {
float ax;
float bx;
float cx;
float ay;
float by;
float cy;
} cal_t;
/*===========================================================================*/
/* External declarations. */
/*===========================================================================*/
#ifdef __cplusplus
extern "C" {
#endif
void tsInit(const TouchscreenDriver *ts);
coord_t tsReadX(void);
coord_t tsReadY(void);
void tsCalibrate(void);
#if TOUCHSCREEN_HAS_IRQ
bool_t tsIRQ(void);
#endif
#if TOUCHSCREEN_HAS_PRESSURE
uint16_t tsReadZ(void);
#endif
#ifdef __cplusplus
}
#endif
#endif /* GFX_USE_TOUCHSCREEN */
#endif /* TOUCHSCREEN_H */
/** @} */

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include/touchscreen_lld.h Normal file
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/*
ChibiOS/GFX - Copyright (C) 2012
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 include/touchscreen_lld.h
* @brief TOUCHSCREEN Driver subsystem low level driver header.
*
* @addtogroup TOUCHSCREEN
* @{
*/
#ifndef TOUCHSCREEN_LLD_H
#define TOUCHSCREEN_LLD_H
#if GFX_USE_TOUCHSCREEN || defined(__DOXYGEN__)
/*===========================================================================*/
/* Include the low level driver configuration information */
/*===========================================================================*/
#include "touchscreen_lld_config.h"
/*===========================================================================*/
/* Error checks. */
/*===========================================================================*/
#ifndef TOUCHSCREEN_NEED_MULTITHREAD
#define TOUCHSCREEN_NEED_MULTITHREAD FALSE
#endif
#ifndef TOUCHSCREEN_XY_INVERTED
#define TOUCHSCREEN_XY_INVERTED FALSE
#endif
#ifndef TOUCHSCREEN_STORE_CALIBRATION
#define TOUCHSCREEN_STORE_CALIBRATION FALSE
#endif
#ifndef TOUCHSCREEN_VERIFY_CALIBRATION
#define TOUCHSCREEN_VERIFY_CALIBRATION FALSE
#endif
#ifndef TOUCHSCREEN_HAS_IRQ
#define TOUCHSCREEN_HAS_IRQ FALSE
#endif
#ifndef TOUCHSCREEN_HAS_PRESSURE
#define TOUCHSCREEN_HAS_PRESSURE FALSE
#endif
#ifndef TOUCHSCREEN_SPI_PROLOGUE
#define TOUCHSCREEN_SPI_PROLOGUE()
#endif
#ifndef TOUCHSCREEN_SPI_EPILOGUE
#define TOUCHSCREEN_SPI_EPILOGUE()
#endif
/*===========================================================================*/
/* Driver types. */
/*===========================================================================*/
/**
* @brief Structure representing a touchscreen driver.
*/
typedef struct TouchscreenDriver {
/*
* @brief Pointer to SPI driver.
* @note SPI driver must be enabled in mcuconf.h and halconf.h
*/
SPIDriver *spip;
/*
* @brief Pointer to the SPI configuration structure.
* @note The lowest possible speed ~ 1-2MHz is to be used, otherwise
* will result in a lot of noise
*/
const SPIConfig *spicfg;
/*
* @brief Touchscreen controller TPIRQ pin GPIO port
*/
ioportid_t tsIRQPort;
/*
* @brief Touchscreen controller TPIRQ GPIO pin
* @note The interface is polled as of now, interrupt support is
* to be implemented in the future.
*/
ioportmask_t tsIRQPin;
/*
* @brief Initialize the SPI with the configuration struct given or not
* If TRUE, spiStart is called by the init, otherwise not
* @note This is provided in such a case when SPI port is being shared
* across multiple peripherals, so not to disturb the SPI bus.
* You can use TOUCHSCREEN_SPI_PROLOGUE() and TOUCHSCREEN_SPI_EPILOGUE()
* macros to change the SPI configuration or speed before and
* after using the touchpad. An example case would be sharing the
* bus with a fast flash memory chip.
*/
bool_t direct_init;
} TouchscreenDriver;
/*===========================================================================*/
/* External declarations. */
/*===========================================================================*/
#ifdef __cplusplus
extern "C" {
#endif
/* Core functions */
void ts_lld_init(const TouchscreenDriver *ts);
uint16_t ts_lld_read_value(uint8_t cmd);
uint16_t ts_lld_read_x(void);
uint16_t ts_lld_read_y(void);
#if TOUCHSCREEN_HAS_IRQ
uint8_t ts_lld_irq(void);
#endif
#if TOUCHSCREEN_HAS_PRESSURE
uint16_t ts_lld_read_z(void);
#endif
#ifdef __cplusplus
}
#endif
#endif /* GFX_USE_TOUCHSCREEN */
#endif /* _TOUCHSCREEN_LLD_H */
/** @} */

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/* ChibiOS/GFX - Copyright (C) 2012
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 src/touchscreen.c
* @brief Touchscreen Driver code.
*
* @addtogroup TOUCHSCREEN
* @{
*/
#include "ch.h"
#include "hal.h"
#include "gdisp.h"
#include "touchscreen.h"
#if GFX_USE_TOUCHSCREEN || defined(__DOXYGEN__)
#if TOUCHSCREEN_STORE_CALIBRATION
extern void ts_store_calibration_lld(struct cal_t *cal);
extern struct cal_t *ts_restore_calibration_lld(void);
#endif
/*===========================================================================*/
/* Driver local definitions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local variables. */
/*===========================================================================*/
static struct cal_t *cal;
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
static coord_t _tsReadRealX(void) {
int32_t results = 0;
int16_t i;
coord_t x;
for(i = 0; i < CONVERSIONS; i++) {
results += ts_lld_read_x();
}
/* Take the average of the readings */
x = results / CONVERSIONS;
return x;
}
static coord_t _tsReadRealY(void) {
int32_t results = 0;
int16_t i;
coord_t y;
for(i = 0; i < CONVERSIONS; i++) {
results += ts_lld_read_y();
}
/* Take the average of the readings */
y = results / CONVERSIONS;
return y;
}
static void _tsDrawCross(uint16_t x, uint16_t y) {
gdispDrawLine(x-15, y, x-2, y, 0xffff);
gdispDrawLine(x+2, y, x+15, y, 0xffff);
gdispDrawLine(x, y-15, x, y-2, 0xffff);
gdispDrawLine(x, y+2, x, y+15, 0xffff);
gdispDrawLine(x-15, y+15, x-7, y+15, RGB565CONVERT(184,158,131));
gdispDrawLine(x-15, y+7, x-15, y+15, RGB565CONVERT(184,158,131));
gdispDrawLine(x-15, y-15, x-7, y-15, RGB565CONVERT(184,158,131));
gdispDrawLine(x-15, y-7, x-15, y-15, RGB565CONVERT(184,158,131));
gdispDrawLine(x+7, y+15, x+15, y+15, RGB565CONVERT(184,158,131));
gdispDrawLine(x+15, y+7, x+15, y+15, RGB565CONVERT(184,158,131));
gdispDrawLine(x+7, y-15, x+15, y-15, RGB565CONVERT(184,158,131));
gdispDrawLine(x+15, y-15, x+15, y-7, RGB565CONVERT(184,158,131));
}
static void _tsTransform(coord_t *x, coord_t *y) {
*x = (coord_t) (cal->ax * (*x) + cal->bx * (*y) + cal->cx);
*y = (coord_t) (cal->ay * (*x) + cal->by * (*y) + cal->cy);
}
static void _tsDo3PointCalibration(const coord_t (*cross)[2], coord_t (*points)[2], cal_t *c) {
float dx, dx0, dx1, dx2, dy0, dy1, dy2;
/* Compute all the required determinants */
dx = ((float)(points[0][0] - points[2][0])) * ((float)(points[1][1] - points[2][1]))
- ((float)(points[1][0] - points[2][0])) * ((float)(points[0][1] - points[2][1]));
dx0 = ((float)(cross[0][0] - cross[2][0])) * ((float)(points[1][1] - points[2][1]))
- ((float)(cross[1][0] - cross[2][0])) * ((float)(points[0][1] - points[2][1]));
dx1 = ((float)(points[0][0] - points[2][0])) * ((float)(cross[1][0] - cross[2][0]))
- ((float)(points[1][0] - points[2][0])) * ((float)(cross[0][0] - cross[2][0]));
dx2 = cross[0][0] * ((float)points[1][0] * (float)points[2][1] - (float)points[2][0] * (float)points[1][1]) -
cross[1][0] * ((float)points[0][0] * (float)points[2][1] - (float)points[2][0] * (float)points[0][1]) +
cross[2][0] * ((float)points[0][0] * (float)points[1][1] - (float)points[1][0] * (float)points[0][1]);
dy0 = ((float)(cross[0][1] - cross[2][1])) * ((float)(points[1][1] - points[2][1]))
- ((float)(cross[1][1] - cross[2][1])) * ((float)(points[0][1] - points[2][1]));
dy1 = ((float)(points[0][0] - points[2][0])) * ((float)(cross[1][1] - cross[2][1]))
- ((float)(points[1][0] - points[2][0])) * ((float)(cross[0][1] - cross[2][1]));
dy2 = cross[0][1] * ((float)points[1][0] * (float)points[2][1] - (float)points[2][0] * (float)points[1][1]) -
cross[1][1] * ((float)points[0][0] * (float)points[2][1] - (float)points[2][0] * (float)points[0][1]) +
cross[2][1] * ((float)points[0][0] * (float)points[1][1] - (float)points[1][0] * (float)points[0][1]);
/* Now, calculate all the required coefficients */
c->ax = dx0 / dx;
c->bx = dx1 / dx;
c->cx = dx2 / dx;
c->ay = dy0 / dx;
c->by = dy1 / dx;
c->cy = dy2 / dx;
}
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Touchscreen Driver initialization.
* @note This function is NOT currently implicitly invoked by @p halInit().
* It must be called manually.
*
* @param[in] ts The touchscreen driver struct
*
* @api
*/
void tsInit(const TouchscreenDriver *ts) {
cal = (struct cal_t*)chHeapAlloc(NULL, sizeof(struct cal_t));
if(cal == NULL)
return;
/* Initialise Mutex */
//MUTEX_INIT
/* Initialise driver */
//MUTEX_ENTER
ts_lld_init(ts);
//MUTEX_EXIT
#if TOUCHSCREEN_STORE_CALIBRATION
cal = ts_restore_calibration_lld();
if(cal == NULL) {
cal = (struct cal_t*)chHeapAlloc(NULL, sizeof(struct cal_t));
tsCalibrate();
}
#endif
}
/**
* @brief Get the X-Coordinate, relative to screen zero point.
*
* @return The X position in pixels.
*
* @api
*/
coord_t tsReadX(void) {
coord_t x, y;
#if TOUCHSCREEN_XY_INVERTED == TRUE
x = _tsReadRealY();
y = _tsReadRealX();
#else
x = _tsReadRealX();
y = _tsReadRealY();
#endif
_tsTransform(&x, &y);
switch(gdispGetOrientation()) {
case GDISP_ROTATE_0:
return x;
case GDISP_ROTATE_90:
return y;
case GDISP_ROTATE_180:
return GDISP_SCREEN_WIDTH - x - 1;
case GDISP_ROTATE_270:
return GDISP_SCREEN_HEIGHT - y - 1;
}
return 0;
}
/**
* @brief Get the X-Coordinate, relative to screen zero point.
*
* @return The Y position in pixels.
*
* @api
*/
coord_t tsReadY(void) {
coord_t x, y;
#if TOUCHSCREEN_XY_INVERTED == TRUE
x = _tsReadRealY();
y = _tsReadRealX();
#else
x = _tsReadRealX();
y = _tsReadRealY();
#endif
_tsTransform(&x, &y);
switch(gdispGetOrientation()) {
case GDISP_ROTATE_0:
return y;
case GDISP_ROTATE_90:
return GDISP_SCREEN_WIDTH - x - 1;
case GDISP_ROTATE_180:
return GDISP_SCREEN_HEIGHT - y - 1;
case GDISP_ROTATE_270:
return x;
}
return 0;
}
/**
* @brief Get the pressure.
*
* @return The pressure.
*
* @api
*/
#if TOUCHSCREEN_HAS_PRESSURE || defined(__DOXYGEN__)
uint16_t tsReadZ(void) {
/* ToDo */
return (ts_lld_read_z());
}
#endif
/**
* @brief Returns if touchscreen is pressed or not
*
* @return TRUE if pressed, FALSE otherwise
*
* @api
*/
#if TOUCHSCREEN_HAS_IRQ || defined(__DOXYGEN__)
bool_t tsIRQ(void) {
return ts_lld_irq();
}
#endif
/* Define maximum no. of times to sample the calibration point */
#define MAX_CAL_SAMPLES 10
/**
* @brief Function to calibrate touchscreen
* @details This function interactively performs calibration of the touchscreen
* using 3-point calibration algorithm. Optionally, it also verifies
* the accuracy of the calibration coefficients obtained if the symbol
* TOUCHSCREEN_VERIFY_CALIBRATION is defined in the configuration.
*
* @api
*/
void tsCalibrate(void) {
const uint16_t height = gdispGetHeight();
const uint16_t width = gdispGetWidth();
const coord_t cross[][2] = {{(width / 4), (height / 4)},
{(width - (width / 4)) , (height / 4)},
{(width - (width / 4)) , (height - (height / 4))},
{(width / 2), (height / 2)}}; /* Check point */
coord_t points[4][2];
int32_t px, py;
uint8_t i, j;
gdispSetOrientation(GDISP_ROTATE_0);
gdispClear(Blue);
gdispFillStringBox(0, 5, gdispGetWidth(), 30, "Calibration", &fontUI2Double, White, Blue, justifyCenter);
#if TOUCHSCREEN_VERIFY_CALIBRATION
calibrate:
for(i = 0; i < 4; i++) {
#else
for(i = 0; i < 3; i++) {
#endif
_tsDrawCross(cross[i][0], cross[i][1]);
while(!tsIRQ())
chThdSleepMilliseconds(2); /* Be nice to other threads*/
chThdSleepMilliseconds(20); /* Allow screen to settle */
/* Take a little more samples per point and their average
* for precise calibration */
px = py = 0;
j = 0;
while (j < MAX_CAL_SAMPLES) {
if (tsIRQ()) {
/* We have valid pointer data */
px += _tsReadRealX();
py += _tsReadRealY();
j++;
}
}
points[i][0] = px / j;
points[i][1] = py / j;
chThdSleepMilliseconds(100);
while(tsIRQ())
chThdSleepMilliseconds(2); /* Be nice to other threads*/
gdispFillArea(cross[i][0] - 15, cross[i][1] - 15, 42, 42, Blue);
}
/* Apply 3 point calibration algorithm */
_tsDo3PointCalibration(cross, points, cal);
#if TOUCHSCREEN_VERIFY_CALIBRATION
/* Verification of correctness of calibration (optional) :
* See if the 4th point (Middle of the screen) coincides with the calibrated
* result. If point is with +/- 2 pixel margin, then successful calibration
* Else, start from the beginning.
*/
/* Transform the co-ordinates */
_tpTransform(&points[3][0], &points[3][1]);
/* Calculate the delta */
px = (points[3][0] - cross[3][0]) * (points[3][0] - cross[3][0]) +
(points[3][1] - cross[3][1]) * (points[3][1] - cross[3][1]);
if(px > 4)
goto calibrate;
#endif
/* If enabled, serialize the calibration values for storage */
#if TOUCHSCREEN_STORE_CALIBRATION
ts_store_calibration_lld(cal);
#endif
}
#endif /* GFX_USE_TOUCHSCREEN */
/** @} */