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nuttx-bb/nuttx/drivers/input/stmpe11_tsc.c

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Add STMPE11 touchscreen logic git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@4703 7fd9a85b-ad96-42d3-883c-3090e2eb8679
2012-05-06 16:00:16 +00:00
/****************************************************************************
* drivers/input/stmpe11_tsc.c
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* References:
* "STMPE811 S-Touch<63> advanced resistive touchscreen controller with 8-bit
* GPIO expander," Doc ID 14489 Rev 6, CD00186725, STMicroelectronics"
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdbool.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <semaphore.h>
#include <poll.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/arch.h>
#include <nuttx/fs/fs.h>
#include <nuttx/i2c.h>
#include <nuttx/wqueue.h>
#include <nuttx/arch.h>
#include <nuttx/input/touchscreen.h>
#include <nuttx/input/stmpe11.h>
#include "stmpe11.h"
#if defined(CONFIG_INPUT) && defined(CONFIG_INPUT_STMPE11) && !defined(CONFIG_STMPE11_TSC_DISABLE)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define Direction_IN 0x00
#define Direction_OUT 0x01
#define Polarity_Low 0x00
#define Polarity_High 0x04
#define Type_Level 0x00
#define Type_Edge 0x02
#define IO_IT_0 0x01
#define IO_IT_1 0x02
#define IO_IT_2 0x04
#define IO_IT_3 0x08
#define IO_IT_4 0x10
#define IO_IT_5 0x20
#define IO_IT_6 0x40
#define IO_IT_7 0x80
#define ALL_IT 0xFF
#define IOE_JOY_IT (uint8_t)(IO_IT_3 | IO_IT_4 | IO_IT_5 | IO_IT_6 | IO_IT_7)
#define IOE_TS_IT (uint8_t)(IO_IT_0 | IO_IT_1 | IO_IT_2)
#define IOE_INMEMS_IT (uint8_t)(IO_IT_2 | IO_IT_3)
#define EDGE_FALLING 0x01
#define EDGE_RISING 0x02
#define TIMEOUT_MAX 0x3000 /*<! The value of the maximal timeout for I2C waiting loops */
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* Internal logic */
static void stmpe11_notify(FAR struct stmpe11_dev_s *priv);
static int stmpe11_sample(FAR struct stmpe11_dev_s *priv,
FAR struct stmpe11_sample_s *sample);
static inline int stmpe11_waitsample(FAR struct stmpe11_dev_s *priv,
FAR struct stmpe11_sample_s *sample);
/* Character driver methods */
static int stmpe11_open(FAR struct file *filep);
static int stmpe11_close(FAR struct file *filep);
static ssize_t stmpe11_read(FAR struct file *filep, FAR char *buffer,
size_t len);
static int stmpe11_ioctl(FAR struct file *filep, int cmd,
unsigned long arg);
#ifndef CONFIG_DISABLE_POLL
static int stmpe11_poll(FAR struct file *filep, struct pollfd *fds,
bool setup);
#endif
/* Initialization logic */
static inline void stmpe11_tscinitialize(FAR struct stmpe11_dev_s *priv);
/****************************************************************************
* Private Data
****************************************************************************/
/* This the the vtable that supports the character driver interface */
static const struct file_operations stmpe11_fops =
{
stmpe11_open, /* open */
stmpe11_close, /* close */
stmpe11_read, /* read */
0, /* write */
0, /* seek */
stmpe11_ioctl /* ioctl */
#ifndef CONFIG_DISABLE_POLL
, stmpe11_poll /* poll */
#endif
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: stmpe11_notify
*
* Description:
* Notify any threads waiting on touchscreen data that data is now
* available for reading.
*
****************************************************************************/
static void stmpe11_notify(FAR struct stmpe11_dev_s *priv)
{
#ifndef CONFIG_DISABLE_POLL
int i;
#endif
/* If there are threads waiting for read data, then signal one of them
* that the read data is available.
*/
if (priv->nwaiters > 0)
{
/* After posting this semaphore, we need to exit because the STMPE11
* is no longer available.
*/
sem_post(&priv->waitsem);
}
/* If there are threads waiting on poll() for STMPE11 data to become available,
* then wake them up now. NOTE: we wake up all waiting threads because we
* do not know that they are going to do. If they all try to read the data,
* then some make end up blocking after all.
*/
#ifndef CONFIG_DISABLE_POLL
for (i = 0; i < CONFIG_STMPE11_NPOLLWAITERS; i++)
{
struct pollfd *fds = priv->fds[i];
if (fds)
{
fds->revents |= POLLIN;
ivdbg("Report events: %02x\n", fds->revents);
sem_post(fds->sem);
}
}
#endif
}
/****************************************************************************
* Name: stmpe11_sample
*
* Description:
* Check if touchscreen sample data is available now and, if so, return
* the sample data. This is part of the stmpe11_read logic.
*
****************************************************************************/
static int stmpe11_sample(FAR struct stmpe11_dev_s *priv,
FAR struct stmpe11_sample_s *sample)
{
irqstate_t flags;
int ret = -EAGAIN;
/* Interrupts me be disabled when this is called to (1) prevent posting
* of semphores from interrupt handlers, and (2) to prevent sampled data
* from changing until it has been reported.
*/
flags = irqsave();
/* Is there new TSC2007 sample data available? */
if (priv->penchange)
{
/* Yes.. the state has changed in some way. Return a copy of the
* sampled data.
*/
memcpy(sample, &priv->sample, sizeof(struct stmpe11_sample_s));
/* Now manage state transitions */
if (sample->contact == CONTACT_UP)
{
/* Next.. no contract. Increment the ID so that next contact ID will be unique */
priv->sample.contact = CONTACT_NONE;
priv->id++;
}
else if (sample->contact == CONTACT_DOWN)
{
/* First report -- next report will be a movement */
priv->sample.contact = CONTACT_MOVE;
}
priv->penchange = false;
ret = OK;
}
irqrestore(flags);
return ret;
}
/****************************************************************************
* Name: stmpe11_waitsample
*
* Description:
* Wait for a sample to become available (this is really part of the
* stmpe11_read logic).
*
****************************************************************************/
static inline int stmpe11_waitsample(FAR struct stmpe11_dev_s *priv,
FAR struct stmpe11_sample_s *sample)
{
irqstate_t flags;
int ret;
/* Interrupts me be disabled when this is called to (1) prevent posting
* of semphores from interrupt handlers, and (2) to prevent sampled data
* from changing until it has been reported.
*
* In addition, we will also disable pre-emption to prevent other threads
* from getting control while we muck with the semaphores.
*/
sched_lock();
flags = irqsave();
/* Now release the semaphore that manages mutually exclusive access to
* the device structure. This may cause other tasks to become ready to
* run, but they cannot run yet because pre-emption is disabled.
*/
sem_post(&priv->exclsem);
/* Try to get the a sample... if we cannot, then wait on the semaphore
* that is posted when new sample data is availble.
*/
while (stmpe11_sample(priv, sample) < 0)
{
/* Wait for a change in the STMPE11 state */
priv->nwaiters++;
ret = sem_wait(&priv->waitsem);
priv->nwaiters--;
if (ret < 0)
{
/* If we are awakened by a signal, then we need to return
* the failure now.
*/
DEBUGASSERT(errno == EINTR);
ret = -EINTR;
goto errout;
}
}
/* Re-acquire the the semaphore that manages mutually exclusive access to
* the device structure. We may have to wait here. But we have our sample.
* Interrupts and pre-emption will be re-enabled while we wait.
*/
ret = sem_wait(&priv->exclsem);
errout:
/* Then re-enable interrupts. We might get interrupt here and there
* could be a new sample. But no new threads will run because we still
* have pre-emption disabled.
*/
irqrestore(flags);
/* Restore pre-emption. We might get suspended here but that is okay
* because we already have our sample. Note: this means that if there
* were two threads reading from the STMPE11 for some reason, the data
* might be read out of order.
*/
sched_unlock();
return ret;
}
/****************************************************************************
* Name: stmpe11_open
*
* Description:
* Standard character driver open method.
*
****************************************************************************/
static int stmpe11_open(FAR struct file *filep)
{
#ifdef CONFIG_STMPE11_REFCNT
FAR struct inode *inode;
FAR struct stmpe11_dev_s *priv;
uint8_t tmp;
int ret;
DEBUGASSERT(filep);
inode = filep->f_inode;
DEBUGASSERT(inode && inode->i_private);
priv = (FAR struct stmpe11_dev_s *)inode->i_private;
/* Get exclusive access to the driver data structure */
ret = sem_wait(&priv->exclsem);
if (ret < 0)
{
/* This should only happen if the wait was canceled by an signal */
DEBUGASSERT(errno == EINTR);
return -EINTR;
}
/* Increment the reference count */
tmp = priv->crefs + 1;
if (tmp == 0)
{
/* More than 255 opens; uint8_t overflows to zero */
ret = -EMFILE;
goto errout_with_sem;
}
/* When the reference increments to 1, this is the first open event
* on the driver.. and an opportunity to do any one-time initialization.
*/
/* Save the new open count on success */
priv->crefs = tmp;
errout_with_sem:
sem_post(&priv->exclsem);
return ret;
#else
return OK;
#endif
}
/****************************************************************************
* Name: stmpe11_close
*
* Description:
* Standard character driver close method.
*
****************************************************************************/
static int stmpe11_close(FAR struct file *filep)
{
#ifdef CONFIG_STMPE11_REFCNT
FAR struct inode *inode;
FAR struct stmpe11_dev_s *priv;
int ret;
DEBUGASSERT(filep);
inode = filep->f_inode;
DEBUGASSERT(inode && inode->i_private);
priv = (FAR struct stmpe11_dev_s *)inode->i_private;
/* Get exclusive access to the driver data structure */
ret = sem_wait(&priv->exclsem);
if (ret < 0)
{
/* This should only happen if the wait was canceled by an signal */
DEBUGASSERT(errno == EINTR);
return -EINTR;
}
/* Decrement the reference count unless it would decrement a negative
* value. When the count decrements to zero, there are no further
* open references to the driver.
*/
if (priv->crefs >= 1)
{
priv->crefs--;
}
sem_post(&priv->exclsem);
#endif
return OK;
}
/****************************************************************************
* Name: stmpe11_read
*
* Description:
* Standard character driver read method.
*
****************************************************************************/
static ssize_t stmpe11_read(FAR struct file *filep, FAR char *buffer, size_t len)
{
FAR struct inode *inode;
FAR struct stmpe11_dev_s *priv;
FAR struct touch_sample_s *report;
struct stmpe11_sample_s sample;
int ret;
DEBUGASSERT(filep);
inode = filep->f_inode;
DEBUGASSERT(inode && inode->i_private);
priv = (FAR struct stmpe11_dev_s *)inode->i_private;
/* Verify that the caller has provided a buffer large enough to receive
* the touch data.
*/
if (len < SIZEOF_TOUCH_SAMPLE_S(1))
{
/* We could provide logic to break up a touch report into segments and
* handle smaller reads... but why?
*/
return -ENOSYS;
}
/* Get exclusive access to the driver data structure */
ret = sem_wait(&priv->exclsem);
if (ret < 0)
{
/* This should only happen if the wait was canceled by an signal */
DEBUGASSERT(errno == EINTR);
return -EINTR;
}
/* Try to read sample data. */
ret = stmpe11_sample(priv, &sample);
if (ret < 0)
{
/* Sample data is not available now. We would ave to wait to get
* receive sample data. If the user has specified the O_NONBLOCK
* option, then just return an error.
*/
if (filep->f_oflags & O_NONBLOCK)
{
ret = -EAGAIN;
goto errout;
}
/* Wait for sample data */
ret = stmpe11_waitsample(priv, &sample);
if (ret < 0)
{
/* We might have been awakened by a signal */
goto errout;
}
}
/* In any event, we now have sampled STMPE11 data that we can report
* to the caller.
*/
report = (FAR struct touch_sample_s *)buffer;
memset(report, 0, SIZEOF_TOUCH_SAMPLE_S(1));
report->npoints = 1;
report->point[0].id = priv->id;
report->point[0].x = sample.x;
report->point[0].y = sample.y;
report->point[0].pressure = sample.z;
/* Report the appropriate flags */
if (sample.contact == CONTACT_UP)
{
/* Pen is now up */
report->point[0].flags = TOUCH_UP | TOUCH_ID_VALID;
}
else
{
if (sample.contact == CONTACT_DOWN)
{
/* First contact */
report->point[0].flags = TOUCH_DOWN | TOUCH_ID_VALID | TOUCH_POS_VALID;
}
else /* if (sample->contact == CONTACT_MOVE) */
{
/* Movement of the same contact */
report->point[0].flags = TOUCH_MOVE | TOUCH_ID_VALID | TOUCH_POS_VALID;
}
/* A pressure measurement of zero means that pressure is not available */
if (report->point[0].pressure != 0)
{
report->point[0].flags |= TOUCH_PRESSURE_VALID;
}
}
ret = SIZEOF_TOUCH_SAMPLE_S(1);
errout:
sem_post(&priv->exclsem);
return ret;
}
/****************************************************************************
* Name: stmpe11_ioctl
*
* Description:
* Standard character driver ioctl method.
*
****************************************************************************/
static int stmpe11_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
{
FAR struct inode *inode;
FAR struct stmpe11_dev_s *priv;
int ret;
ivdbg("cmd: %d arg: %ld\n", cmd, arg);
DEBUGASSERT(filep);
inode = filep->f_inode;
DEBUGASSERT(inode && inode->i_private);
priv = (FAR struct stmpe11_dev_s *)inode->i_private;
/* Get exclusive access to the driver data structure */
ret = sem_wait(&priv->exclsem);
if (ret < 0)
{
/* This should only happen if the wait was canceled by an signal */
DEBUGASSERT(errno == EINTR);
return -EINTR;
}
/* Process the IOCTL by command */
switch (cmd)
{
case TSIOC_SETFREQUENCY: /* arg: Pointer to uint32_t frequency value */
{
FAR uint32_t *ptr = (FAR uint32_t *)((uintptr_t)arg);
DEBUGASSERT(priv->config != NULL && ptr != NULL);
priv->config->frequency = I2C_SETFREQUENCY(priv->i2c, *ptr);
}
break;
case TSIOC_GETFREQUENCY: /* arg: Pointer to uint32_t frequency value */
{
FAR uint32_t *ptr = (FAR uint32_t *)((uintptr_t)arg);
DEBUGASSERT(priv->config != NULL && ptr != NULL);
*ptr = priv->config->frequency;
}
break;
default:
ret = -ENOTTY;
break;
}
sem_post(&priv->exclsem);
return ret;
}
/****************************************************************************
* Name: stmpe11_poll
*
* Description:
* Standard character driver poll method.
*
****************************************************************************/
#ifndef CONFIG_DISABLE_POLL
static int stmpe11_poll(FAR struct file *filep, FAR struct pollfd *fds,
bool setup)
{
FAR struct inode *inode;
FAR struct stmpe11_dev_s *priv;
int ret;
int i;
ivdbg("setup: %d\n", (int)setup);
DEBUGASSERT(filep && fds);
inode = filep->f_inode;
DEBUGASSERT(inode && inode->i_private);
priv = (FAR struct stmpe11_dev_s *)inode->i_private;
/* Are we setting up the poll? Or tearing it down? */
ret = sem_wait(&priv->exclsem);
if (ret < 0)
{
/* This should only happen if the wait was canceled by an signal */
DEBUGASSERT(errno == EINTR);
return -EINTR;
}
if (setup)
{
/* Ignore waits that do not include POLLIN */
if ((fds->events & POLLIN) == 0)
{
idbg("Missing POLLIN: revents: %08x\n", fds->revents);
ret = -EDEADLK;
goto errout;
}
/* This is a request to set up the poll. Find an available
* slot for the poll structure reference
*/
for (i = 0; i < CONFIG_STMPE11_NPOLLWAITERS; i++)
{
/* Find an available slot */
if (!priv->fds[i])
{
/* Bind the poll structure and this slot */
priv->fds[i] = fds;
fds->priv = &priv->fds[i];
break;
}
}
if (i >= CONFIG_STMPE11_NPOLLWAITERS)
{
idbg("No availabled slot found: %d\n", i);
fds->priv = NULL;
ret = -EBUSY;
goto errout;
}
/* Should we immediately notify on any of the requested events? */
if (priv->penchange)
{
stmpe11_notify(priv);
}
}
else if (fds->priv)
{
/* This is a request to tear down the poll. */
struct pollfd **slot = (struct pollfd **)fds->priv;
DEBUGASSERT(slot != NULL);
/* Remove all memory of the poll setup */
*slot = NULL;
fds->priv = NULL;
}
errout:
sem_post(&priv->exclsem);
return ret;
}
#endif
/****************************************************************************
* Name: stmpe11_tscinitialize
*
* Description:
* Initialize the touchscreen controller. This is really a part of the
* stmpe11_register logic,
*
****************************************************************************/
static inline void stmpe11_tscinitialize(FAR struct stmpe11_dev_s *priv)
{
uint8_t regval = 0;
/* Enable TSC and ADC functions */
regval = stmpe11_getreg8(priv, STMPE11_SYS_CTRL2);
regval &= ~(SYS_CTRL2_TSC_OFF | SYS_CTRL2_ADC_OFF);
stmpe11_putreg8(priv, STMPE11_SYS_CTRL2, regval);
/* Enable the TSC global interrupts */
regval = stmpe11_getreg8(priv, STMPE11_INT_EN);
regval |= (uint32_t)(INT_TOUCH_DET | INT_FIFO_TH | INT_FIFO_OFLOW);
stmpe11_putreg8(priv, STMPE11_INT_EN, regval);
/* Select Sample Time, bit number and ADC Reference */
stmpe11_putreg8(priv, STMPE11_ADC_CTRL1, priv->config->ctrl1);
/* Wait for 20 ms */
up_mdelay(20);
/* Select the ADC clock speed */
stmpe11_putreg8(priv, STMPE11_ADC_CTRL2, priv->config->ctrl2);
/* Select TSC pins in non-GPIO mode (AF=0) */
regval = stmpe11_getreg8(priv, STMPE11_GPIO_AF);
regval &= ~(uint8_t)TSC_PIN_SET;
stmpe11_putreg8(priv, STMPE11_GPIO_AF, regval);
/* Select 2 nF filter capacitor */
stmpe11_putreg8(priv, STMPE11_TSC_CFG,
(TSC_CFG_AVE_CTRL_4SAMPLES | TSC_CFG_TOUCH_DELAY_500US | TSC_CFG_SETTLING_500US));
/* Select single point reading */
stmpe11_putreg8(priv, STMPE11_FIFO_TH, 1);
/* Reset and clear the FIFO. */
stmpe11_putreg8(priv, STMPE11_FIFO_STA, FIFO_STA_FIFO_RESET);
stmpe11_putreg8(priv, STMPE11_FIFO_STA, 0);
/* set the data format for Z value: 7 fractional part and 1 whole part */
stmpe11_putreg8(priv, STMPE11_TSC_FRACTIONZ, 0x01);
/* Set the driving capability of the device for TSC pins: 50mA */
stmpe11_putreg8(priv, STMPE11_TSC_IDRIVE, TSC_IDRIVE_50MA);
/* Enable the TSC. Use no tracking index, touch-screen controller
* operation mode (XYZ).
*/
stmpe11_putreg8(priv, STMPE11_TSC_CTRL, TSC_CTRL_EN);
/* Clear all the status pending bits */
stmpe11_putreg8(priv, STMPE11_INT_STA, INT_ALL);
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: stmpe11_register
*
* Description:
* Enable TSC functionality. GPIO4-7 must be available. This function
* will register the touchsceen driver as /dev/inputN where N is the minor
* device number
*
* Input Parameters:
* handle - The handle previously returned by stmpe11_register
* minor - The input device minor number
*
* Returned Value:
* Zero is returned on success. Otherwise, a negated errno value is
* returned to indicate the nature of the failure.
*
****************************************************************************/
int stmpe11_register(STMPE11_HANDLE handle, int minor)
{
FAR struct stmpe11_dev_s *priv = (FAR struct stmpe11_dev_s *)handle;
int ret;
DEBUGASSERT(priv);
/* Get exclusive access to the device structure */
ret = sem_wait(&priv->exclsem);
if (ret < 0)
{
int errval = errno;
idbg("sem_wait failed: %d\n", errval);
return -errval;
}
/* Make sure that the pins (4-7) need by the TSC are not already in use */
if ((priv->inuse & TSC_PIN_SET) != 0)
{
idbg("TSC pins is already in-use: %02x\n", priv->inuse);
sem_post(&priv->exclsem);
return -EBUSY;
}
/* Update the configuration structure to show that the TSC function is allocated */
priv->inuse |= TSC_PIN_SET; /* Pins 4-7 are now in-use */
priv->flags |= STMPE11_FLAGS_TSC_INITIALIZED; /* TSC function is initialized */
priv->minor = minor; /* Save the minor number */
/* Initialize the touchscreen controller */
stmpe11_tscinitialize(priv);
/* Initialize the TS structure to their default values */
priv->penchange = false;
priv->threshx = 0;
priv->threshy = 0;
priv->flags |= STMPE11_FLAGS_GPIO_INITIALIZED;
sem_post(&priv->exclsem);
return OK;
}
/****************************************************************************
* Name: stmpe11_tscworker
*
* Description:
* This function is called to handle a TSC interrupt. It is not really
* an interrupt handle because it is called from the STMPE11 "bottom half"
* logic that runs on the worker thread.
*
****************************************************************************/
void stmpe11_tscworker(FAR struct stmpe11_dev_s *priv)
{
FAR struct stmpe11_config_s *config; /* Convenience pointer */
bool pendown; /* true: pend is down */
uint16_t xdiff; /* X difference used in thresholding */
uint16_t ydiff; /* Y difference used in thresholding */
uint16_t x; /* X position */
uint16_t y; /* Y position */
ASSERT(priv != NULL);
/* Get a pointer the callbacks for convenience (and so the code is not so
* ugly).
*/
config = priv->config;
DEBUGASSERT(config != NULL);
/* Check if the Touch detect event happened */
/* Check for pen up or down from the TSC_STA ibit n the STMPE11_TSC_CTRL register. */
pendown = (stmpe11_getreg8(priv, STMPE11_TSC_CTRL) & STMPE11_TSC_CTRL) != 0;
/* Handle the change from pen down to pen up */
if (!pendown)
{
/* Ignore the interrupt if the pen was already down (CONTACT_NONE == pen up and
* already reported. CONTACT_UP == pen up, but not reported)
*/
if (priv->sample.contact == CONTACT_NONE)
{
goto errout;
}
}
else
{
/* Read the next x and y positions */
x = stmpe11_getreg16(priv, STMPE11_TSC_DATAX);
y = stmpe11_getreg16(priv, STMPE11_TSC_DATAY);
/* Perform a threasholding operation so that the results will be more stable */
xdiff = x > priv->threshx ? (x - priv->threshx) : (priv->threshx - x);
ydiff = y > priv->threshy ? (y - priv->threshy) : (priv->threshy - y);
/* When we see a big difference, snap to the new x/y position */
if (xdiff + ydiff > 5)
{
priv->threshx = x;
priv->threshy = y;
}
/* Update the x/y position */
priv->sample.x = priv->threshx;
priv->sample.y = priv->threshy;
/* Update the Z pression index */
priv->sample.z = stmpe11_getreg8(priv, STMPE11_TSC_DATAZ);
/* Clear the interrupt pending bit and enable the FIFO again */
stmpe11_putreg8(priv, STMPE11_FIFO_STA, 0x01);
stmpe11_putreg8(priv, STMPE11_FIFO_STA, 0x00);
}
/* Note the availability of new measurements */
if (pendown)
{
/* If this is the first (acknowledged) pend down report, then report
* this as the first contact. If contact == CONTACT_DOWN, it will be
* set to set to CONTACT_MOVE after the contact is first sampled.
*/
if (priv->sample.contact != CONTACT_MOVE)
{
/* First contact */
priv->sample.contact = CONTACT_DOWN;
}
}
else /* if (priv->sample.contact != CONTACT_NONE) */
{
/* The pen is up. NOTE: We know from a previous test, that this is a
* loss of contact condition. This will be changed to CONTACT_NONE
* after the loss of contact is sampled.
*/
priv->sample.contact = CONTACT_UP;
}
/* Indicate the availability of new sample data for this ID */
priv->sample.id = priv->id;
priv->penchange = true;
/* Notify any waiters that nes STMPE11 data is available */
stmpe11_notify(priv);
/* Exit, re-enabling STMPE11 interrupts */
errout:
config->enable(config, true);
}
#endif /* CONFIG_INPUT && CONFIG_INPUT_STMPE11 && !CONFIG_STMPE11_TSC_DISABLE */