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incubator-nuttx/drivers/input/tsc2007.c

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/****************************************************************************
* drivers/input/tsc2007.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/* The TSC2007 is an analog interface circuit for a human interface touch
* screen device. All peripheral functions are controlled through the command
* byte and onboard state machines.
*
* References:
* "1.2V to 3.6V, 12-Bit, Nanopower, 4-Wire Micro TOUCH SCREEN CONTROLLER
* with I2C Interface," SBAS405A March 2007, Revised, March 2009, Texas
* Instruments Incorporated
*/
/****************************************************************************
* 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 <poll.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/irq.h>
#include <nuttx/kmalloc.h>
#include <nuttx/arch.h>
#include <nuttx/fs/fs.h>
#include <nuttx/i2c/i2c_master.h>
#include <nuttx/mutex.h>
#include <nuttx/semaphore.h>
#include <nuttx/wqueue.h>
#include <nuttx/random.h>
#include <nuttx/signal.h>
#include <nuttx/input/touchscreen.h>
#include <nuttx/input/tsc2007.h>
#include "tsc2007.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* Reference counting is partially implemented, but not needed in the
* current design.
*/
#undef CONFIG_TSC2007_REFCNT
/* I don't think that it is necessary to activate the converters before
* making measurements. However, I will keep this functionality enabled
* until I have a change to prove that that activation is unnecessary.
*/
#undef CONFIG_TSC2007_ACTIVATE
#define CONFIG_TSC2007_ACTIVATE 1
/* Driver support ***********************************************************/
/* This format is used to construct the /dev/input[n] device driver path. It
* defined here so that it will be used consistently in all places.
*/
#define DEV_FORMAT "/dev/input%d"
#define DEV_NAMELEN 16
/* Commands *****************************************************************/
#define TSC2007_SETUP (TSC2007_CMD_FUNC_SETUP)
#ifdef CONFIG_TSC2007_8BIT
# define TSC2007_ACTIVATE_Y (TSC2007_CMD_8BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_YON)
# define TSC2007_MEASURE_Y (TSC2007_CMD_8BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_YPOS)
# define TSC2007_ACTIVATE_X (TSC2007_CMD_8BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_XON)
# define TSC2007_MEASURE_X (TSC2007_CMD_8BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_XPOS)
# define TSC2007_ACTIVATE_Z (TSC2007_CMD_8BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_YXON)
# define TSC2007_MEASURE_Z1 (TSC2007_CMD_8BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_Z1POS)
# define TSC2007_MEASURE_Z2 (TSC2007_CMD_8BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_Z2POS)
# define TSC2007_ENABLE_PENIRQ (TSC2007_CMD_8BIT | TSC2007_CMD_PWRDN_IRQEN)
#else
# define TSC2007_ACTIVATE_Y (TSC2007_CMD_12BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_YON)
# define TSC2007_MEASURE_Y (TSC2007_CMD_12BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_YPOS)
# define TSC2007_ACTIVATE_X (TSC2007_CMD_12BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_XON)
# define TSC2007_MEASURE_X (TSC2007_CMD_12BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_XPOS)
# define TSC2007_ACTIVATE_Z (TSC2007_CMD_12BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_YXON)
# define TSC2007_MEASURE_Z1 (TSC2007_CMD_12BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_Z1POS)
# define TSC2007_MEASURE_Z2 (TSC2007_CMD_12BIT | TSC2007_CMD_ADCON_IRQDIS | TSC2007_CMD_FUNC_Z2POS)
# define TSC2007_ENABLE_PENIRQ (TSC2007_CMD_12BIT | TSC2007_CMD_PWRDN_IRQEN)
#endif
/****************************************************************************
* Private Types
****************************************************************************/
/* This describes the state of one contact */
enum tsc2007_contact_e
{
CONTACT_NONE = 0, /* No contact */
CONTACT_DOWN, /* First contact */
CONTACT_MOVE, /* Same contact, possibly different position */
CONTACT_UP, /* Contact lost */
};
/* This structure describes the results of one TSC2007 sample */
struct tsc2007_sample_s
{
uint8_t id; /* Sampled touch point ID */
uint8_t contact; /* Contact state (see enum tsc2007_contact_e) */
bool valid; /* True: x,y,pressure contain valid, sampled data */
uint16_t x; /* Measured X position */
uint16_t y; /* Measured Y position */
uint16_t pressure; /* Calculated pressure */
};
/* This structure describes the state of one TSC2007 driver instance */
struct tsc2007_dev_s
{
#ifdef CONFIG_TSC2007_MULTIPLE
FAR struct tsc2007_dev_s *flink; /* Supports a singly linked list of drivers */
#endif
#ifdef CONFIG_TSC2007_REFCNT
uint8_t crefs; /* Number of times the device has been opened */
#endif
uint8_t nwaiters; /* Number of threads waiting for TSC2007 data */
uint8_t id; /* Current touch point ID */
volatile bool penchange; /* An unreported event is buffered */
mutex_t devlock; /* Manages exclusive access to this structure */
sem_t waitsem; /* Used to wait for the availability of data */
FAR struct tsc2007_config_s *config; /* Board configuration data */
FAR struct i2c_master_s *i2c; /* Saved I2C driver instance */
struct work_s work; /* Supports the interrupt handling "bottom half" */
struct tsc2007_sample_s sample; /* Last sampled touch point data */
/* The following is a list if poll structures of threads waiting for
* driver events. The 'struct pollfd' reference for each open is also
* retained in the f_priv field of the 'struct file'.
*/
FAR struct pollfd *fds[CONFIG_TSC2007_NPOLLWAITERS];
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static void tsc2007_notify(FAR struct tsc2007_dev_s *priv);
static int tsc2007_sample(FAR struct tsc2007_dev_s *priv,
FAR struct tsc2007_sample_s *sample);
static int tsc2007_waitsample(FAR struct tsc2007_dev_s *priv,
FAR struct tsc2007_sample_s *sample);
#ifdef CONFIG_TSC2007_ACTIVATE
static int tsc2007_activate(FAR struct tsc2007_dev_s *priv, uint8_t cmd);
#endif
static int tsc2007_transfer(FAR struct tsc2007_dev_s *priv, uint8_t cmd);
static void tsc2007_worker(FAR void *arg);
static int tsc2007_interrupt(int irq, FAR void *context);
/* Character driver methods */
static int tsc2007_open(FAR struct file *filep);
static int tsc2007_close(FAR struct file *filep);
static ssize_t tsc2007_read(FAR struct file *filep, FAR char *buffer,
size_t len);
static int tsc2007_ioctl(FAR struct file *filep, int cmd, unsigned long arg);
static int tsc2007_poll(FAR struct file *filep, FAR struct pollfd *fds,
bool setup);
/****************************************************************************
* Private Data
****************************************************************************/
/* This the vtable that supports the character driver interface */
static const struct file_operations g_tsc2007_fops =
{
tsc2007_open, /* open */
tsc2007_close, /* close */
tsc2007_read, /* read */
NULL, /* write */
NULL, /* seek */
tsc2007_ioctl, /* ioctl */
NULL, /* mmap */
NULL, /* truncate */
tsc2007_poll /* poll */
};
/* If only a single TSC2007 device is supported, then the driver state
* structure may as well be pre-allocated.
*/
#ifndef CONFIG_TSC2007_MULTIPLE
static struct tsc2007_dev_s g_tsc2007;
/* Otherwise, we will need to maintain allocated driver instances in a list */
#else
static struct tsc2007_dev_s *g_tsc2007list;
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: tsc2007_notify
****************************************************************************/
static void tsc2007_notify(FAR struct tsc2007_dev_s *priv)
{
/* If there are threads waiting on poll() for TSC2007 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.
*/
poll_notify(priv->fds, CONFIG_TSC2007_NPOLLWAITERS, POLLIN);
/* 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 TSC2007
* is no longer available.
*/
nxsem_post(&priv->waitsem);
}
}
/****************************************************************************
* Name: tsc2007_sample
****************************************************************************/
static int tsc2007_sample(FAR struct tsc2007_dev_s *priv,
FAR struct tsc2007_sample_s *sample)
{
irqstate_t flags;
int ret = -EAGAIN;
/* Interrupts must be disabled when this is called to (1) prevent posting
* of semaphores from interrupt handlers, and (2) to prevent sampled data
* from changing until it has been reported.
*/
flags = enter_critical_section();
/* 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 tsc2007_sample_s));
/* Now manage state transitions */
if (sample->contact == CONTACT_UP)
{
/* Next.. no contact. Increment the ID so that next contact ID
* will be unique. X/Y positions are no longer valid.
*/
priv->sample.contact = CONTACT_NONE;
priv->sample.valid = false;
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;
}
leave_critical_section(flags);
return ret;
}
/****************************************************************************
* Name: tsc2007_waitsample
****************************************************************************/
static int tsc2007_waitsample(FAR struct tsc2007_dev_s *priv,
FAR struct tsc2007_sample_s *sample)
{
irqstate_t flags;
int ret;
/* Interrupts must be disabled when this is called to (1) prevent posting
* of semaphores 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.
*/
flags = enter_critical_section();
/* 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.
*/
nxmutex_unlock(&priv->devlock);
/* Try to get the a sample... if we cannot, then wait on the semaphore
* that is posted when new sample data is available.
*/
while (tsc2007_sample(priv, sample) < 0)
{
/* Wait for a change in the TSC2007 state */
priv->nwaiters++;
ret = nxsem_wait(&priv->waitsem);
priv->nwaiters--;
if (ret < 0)
{
ierr("ERROR: nxsem_wait failed: %d\n", ret);
goto errout;
}
}
/* Re-acquire 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 = nxmutex_lock(&priv->devlock);
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.
*/
leave_critical_section(flags);
return ret;
}
/****************************************************************************
* Name: tsc2007_activate
****************************************************************************/
#ifdef CONFIG_TSC2007_ACTIVATE
static int tsc2007_activate(FAR struct tsc2007_dev_s *priv, uint8_t cmd)
{
struct i2c_msg_s msg;
uint8_t data;
int ret;
/* Send the setup command (with no ACK) followed by the A/D converter
* activation command (ACKed).
*/
data = TSC2007_SETUP;
msg.frequency = priv->config->frequency; /* I2C frequency */
msg.addr = priv->config->address; /* 7-bit address */
msg.flags = 0; /* Write transaction, beginning with START */
msg.buffer = &data; /* Transfer from this address */
msg.length = 1; /* Send one byte following the address */
/* Ignore errors from the setup command (because it is not ACKed) */
I2C_TRANSFER(priv->i2c, &msg, 1);
/* Now activate the A/D converter */
data = cmd;
msg.frequency = priv->config->frequency; /* I2C frequency */
msg.addr = priv->config->address; /* 7-bit address */
msg.flags = 0; /* Write transaction, beginning with START */
msg.buffer = &data; /* Transfer from this address */
msg.length = 1; /* Send one byte following the address */
ret = I2C_TRANSFER(priv->i2c, &msg, 1);
if (ret < 0)
{
ierr("ERROR: I2C_TRANSFER failed: %d\n", ret);
}
return ret;
}
#else
# define tsc2007_activate(p,c)
#endif
/****************************************************************************
* Name: tsc2007_transfer
****************************************************************************/
static int tsc2007_transfer(FAR struct tsc2007_dev_s *priv, uint8_t cmd)
{
struct i2c_msg_s msg;
uint8_t data12[2];
int ret;
/* "A conversion/write cycle begins when the master issues the address
* byte containing the slave address of the TSC2007, with the eighth bit
* equal to a 0 (R/W = 0)... Once the eighth bit has been received...
* the TSC2007 issues an acknowledge.
*
* "When the master receives the acknowledge bit from the TSC2007, the
* master writes the command byte to the slave... After the command byte
* is received by the slave, the slave issues another acknowledge bit.
* The master then ends the write cycle by issuing a repeated START or a
* STOP condition...
*/
msg.frequency = priv->config->frequency; /* I2C frequency */
msg.addr = priv->config->address; /* 7-bit address */
msg.flags = 0; /* Write transaction, beginning with START */
msg.buffer = &cmd; /* Transfer from this address */
msg.length = 1; /* Send one byte following the address */
ret = I2C_TRANSFER(priv->i2c, &msg, 1);
if (ret < 0)
{
ierr("ERROR: I2C_TRANSFER failed: %d\n", ret);
return ret;
}
/* "The input multiplexer channel for the A/D converter is selected when
* bits C3 through C0 are clocked in. If the selected channel is an X-,Y-,
* or Z-position measurement, the appropriate drivers turn on once the
* acquisition period begins.
*
* "... the input sample acquisition period starts on the falling edge of
* SCL when the C0 bit of the command byte has been latched, and ends
* when a STOP or repeated START condition has been issued. A/D conversion
* starts immediately after the acquisition period...
*
* "For best performance, the I2C bus should remain in an idle state while
* an A/D conversion is taking place. ... The master should wait for at
* least 10ms before attempting to read data from the TSC2007...
*/
nxsig_usleep(10 * 1000);
/* "Data access begins with the master issuing a START condition followed
* by the address byte ... with R/W = 1.
*
* "When the eighth bit has been received and the address matches, the
* slave issues an acknowledge. The first byte of serial data then follows
* (D11-D4, MSB first).
*
* "After the first byte has been sent by the slave, it releases the SDA
* line for the master to issue an acknowledge. The slave responds with
* the second byte of serial data upon receiving the acknowledge from the
* master (D3-D0, followed by four 0 bits). The second byte is followed by
* a NOT acknowledge bit (ACK = 1) from the master to indicate that the
* last data byte has been received...
*/
msg.frequency = priv->config->frequency; /* I2C frequency */
msg.addr = priv->config->address; /* 7-bit address */
msg.flags = I2C_M_READ; /* Read transaction, beginning with START */
msg.buffer = data12; /* Transfer to this address */
msg.length = 2; /* Read two bytes following the address */
ret = I2C_TRANSFER(priv->i2c, &msg, 1);
if (ret < 0)
{
ierr("ERROR: I2C_TRANSFER failed: %d\n", ret);
return ret;
}
/* Get the MS 8 bits from the first byte and the remaining LS 4 bits from
* the second byte. The valid range of data is then from 0 to 4095 with
* the LSB unit corresponding to Vref/4096.
*/
ret = (unsigned int)data12[0] << 4 | (unsigned int)data12[1] >> 4;
iinfo("data: 0x%04x\n", ret);
return ret;
}
/****************************************************************************
* Name: tsc2007_worker
****************************************************************************/
static void tsc2007_worker(FAR void *arg)
{
FAR struct tsc2007_dev_s *priv = (FAR struct tsc2007_dev_s *)arg;
FAR struct tsc2007_config_s *config; /* Convenience pointer */
bool pendown; /* true: pend is down */
uint16_t x; /* X position */
uint16_t y; /* Y position */
uint16_t z1; /* Z1 position */
uint16_t z2; /* Z2 position */
uint32_t pressure; /* Measured pressure */
DEBUGASSERT(priv != NULL);
/* Get exclusive access to the driver data structure */
nxmutex_lock(&priv->devlock);
/* Get a pointer the callbacks for convenience (and so the code is not so
* ugly).
*/
config = priv->config;
DEBUGASSERT(config != NULL);
/* Check for pen up or down by reading the PENIRQ GPIO. */
pendown = config->pendown(config);
/* 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;
}
}
/* It is a pen down event. If the last loss-of-contact event has not been
* processed yet, then we have to ignore the pen down event (or else it
* will look like a drag event)
*/
else if (priv->sample.contact == CONTACT_UP)
{
goto errout;
}
else
{
/* Handle all pen down events. First, sample X, Y, Z1, and Z2 values.
*
* "A resistive touch screen operates by applying a voltage across a
* resistor network and measuring the change in resistance at a given
* point on the matrix where the screen is touched by an input
* (stylus, pen, or finger). The change in the resistance ratio marks
* the location on the touch screen.
*
* "The 4-wire touch screen panel works by applying a voltage across
* the vertical or horizontal resistive network. The A/D converter
* converts the voltage measured at the point where the panel is
* touched. A measurement of the Y position of the pointing device is
* made by connecting the X+ input to a data converter chip, turning
* on the Y+ and Y- drivers, and digitizing the voltage seen at the
* X+ input ..."
*
* "... it is recommended that whenever the host writes to the TSC2007,
* the master processor masks the interrupt associated to PENIRQ.
* This masking prevents false triggering of interrupts when the
* PENIRQ line is disabled in the cases previously listed."
*/
tsc2007_activate(priv, TSC2007_ACTIVATE_X);
y = tsc2007_transfer(priv, TSC2007_MEASURE_Y);
/* "Voltage is then applied to the other axis, and the A/D converter
* converts the voltage representing the X position on the screen.
* This process provides the X and Y coordinates to the associated
* processor."
*/
tsc2007_activate(priv, TSC2007_ACTIVATE_Y);
x = tsc2007_transfer(priv, TSC2007_MEASURE_X);
/* "... To determine pen or finger touch, the pressure of the touch
* must be determined. ... There are several different ways of
* performing this measurement. The TSC2007 supports two methods. The
* first method requires knowing the X-plate resistance, the
* measurement of the X-position, and two additional cross panel
* measurements (Z2 and Z1) of the touch screen."
*
* Rtouch = Rxplate * (X / 4096)* (Z2/Z1 - 1)
*
* "The second method requires knowing both the X-plate and Y-plate
* resistance, measurement of X-position and Y-position, and Z1 ..."
*
* Rtouch = Rxplate * (X / 4096) * (4096/Z1 - 1) -
* Ryplate * (1 - Y/4096)
*
* Read Z1 and Z2 values.
*/
tsc2007_activate(priv, TSC2007_ACTIVATE_Z);
z1 = tsc2007_transfer(priv, TSC2007_MEASURE_Z1);
tsc2007_activate(priv, TSC2007_ACTIVATE_Z);
z2 = tsc2007_transfer(priv, TSC2007_MEASURE_Z2);
/* Power down ADC and enable PENIRQ */
tsc2007_transfer(priv, TSC2007_ENABLE_PENIRQ);
/* Now calculate the pressure using the first method, reduced to:
*
* Rtouch = X * Rxplate *(Z2 - Z1) * / Z1 / 4096
*/
if (z1 == 0)
{
ierr("ERROR: Z1 zero\n");
pressure = 0;
}
else
{
pressure = (x * config->rxplate * (z2 - z1)) / z1;
pressure = (pressure + 2048) >> 12;
iinfo("Position: (%d,%4d) pressure: %u z1/2: (%d,%d)\n",
x, y, pressure, z1, z2);
/* Ignore out of range caculcations */
if (pressure > 0x0fff)
{
ierr("ERROR: Dropped out-of-range pressure: %d\n", pressure);
pressure = 0;
}
}
/* Save the measurements */
priv->sample.x = x;
priv->sample.y = y;
priv->sample.pressure = pressure;
priv->sample.valid = true;
add_ui_randomness((x << 16) ^ y ^ (pressure << 9));
}
/* Note the availability of new measurements */
if (pendown)
{
/* If this is the first (acknowledged) pen 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 new TSC2007 data is available */
tsc2007_notify(priv);
/* Exit, re-enabling TSC2007 interrupts */
errout:
config->enable(config, true);
nxmutex_unlock(&priv->devlock);
}
/****************************************************************************
* Name: tsc2007_interrupt
****************************************************************************/
static int tsc2007_interrupt(int irq, FAR void *context)
{
FAR struct tsc2007_dev_s *priv;
FAR struct tsc2007_config_s *config;
int ret;
/* Which TSC2007 device caused the interrupt? */
#ifndef CONFIG_TSC2007_MULTIPLE
priv = &g_tsc2007;
#else
for (priv = g_tsc2007list;
priv && priv->configs->irq != irq;
priv = priv->flink);
DEBUGASSERT(priv != NULL);
#endif
/* Get a pointer the callbacks for convenience (and so the code is not so
* ugly).
*/
config = priv->config;
DEBUGASSERT(config != NULL);
/* Disable further interrupts */
config->enable(config, false);
/* Transfer processing to the worker thread. Since TSC2007 interrupts are
* disabled while the work is pending, no special action should be required
* to protected the work queue.
*/
DEBUGASSERT(priv->work.worker == NULL);
ret = work_queue(HPWORK, &priv->work, tsc2007_worker, priv, 0);
if (ret != 0)
{
ierr("ERROR: Failed to queue work: %d\n", ret);
}
/* Clear any pending interrupts and return success */
config->clear(config);
return OK;
}
/****************************************************************************
* Name: tsc2007_open
****************************************************************************/
static int tsc2007_open(FAR struct file *filep)
{
#ifdef CONFIG_TSC2007_REFCNT
FAR struct inode *inode;
FAR struct tsc2007_dev_s *priv;
uint8_t tmp;
int ret;
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
priv = inode->i_private;
/* Get exclusive access to the driver data structure */
ret = nxmutex_lock(&priv->devlock);
if (ret < 0)
{
ierr("ERROR: nxsem_wait failed: %d\n", ret);
return ret;
}
/* 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_lock;
}
/* 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_lock:
nxmutex_unlock(&priv->devlock);
return ret;
#else
return OK;
#endif
}
/****************************************************************************
* Name: tsc2007_close
****************************************************************************/
static int tsc2007_close(FAR struct file *filep)
{
#ifdef CONFIG_TSC2007_REFCNT
FAR struct inode *inode;
FAR struct tsc2007_dev_s *priv;
int ret;
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
priv = inode->i_private;
/* Get exclusive access to the driver data structure */
ret = nxmutex_lock(&priv->devlock);
if (ret < 0)
{
ierr("ERROR: nxsem_wait failed: %d\n", ret);
return ret;
}
/* 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--;
}
nxmutex_unlock(&priv->devlock);
#endif
return OK;
}
/****************************************************************************
* Name: tsc2007_read
****************************************************************************/
static ssize_t tsc2007_read(FAR struct file *filep, FAR char *buffer,
size_t len)
{
FAR struct inode *inode;
FAR struct tsc2007_dev_s *priv;
FAR struct touch_sample_s *report;
struct tsc2007_sample_s sample;
int ret;
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
priv = 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 = nxmutex_lock(&priv->devlock);
if (ret < 0)
{
ierr("ERROR: nxsem_wait failed: %d\n", ret);
return ret;
}
/* Try to read sample data. */
ret = tsc2007_sample(priv, &sample);
if (ret < 0)
{
/* Sample data is not available now. We would ave to wait to 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 = tsc2007_waitsample(priv, &sample);
if (ret < 0)
{
/* We might have been awakened by a signal */
goto errout;
}
}
/* In any event, we now have sampled TSC2007 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.pressure;
/* Report the appropriate flags */
if (sample.contact == CONTACT_UP)
{
/* Pen is now up. Is the positional data valid? This is important to
* know because the release will be sent to the window based on its
* last positional data.
*/
if (sample.valid)
{
report->point[0].flags = TOUCH_UP | TOUCH_ID_VALID |
TOUCH_POS_VALID | TOUCH_PRESSURE_VALID;
}
else
{
report->point[0].flags = TOUCH_UP | TOUCH_ID_VALID;
}
}
else
{
if (sample.contact == CONTACT_DOWN)
{
/* Loss of 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:
nxmutex_unlock(&priv->devlock);
return ret;
}
/****************************************************************************
* Name: tsc2007_ioctl
****************************************************************************/
static int tsc2007_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
{
FAR struct inode *inode;
FAR struct tsc2007_dev_s *priv;
int ret;
iinfo("cmd: %d arg: %ld\n", cmd, arg);
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
priv = inode->i_private;
/* Get exclusive access to the driver data structure */
ret = nxmutex_lock(&priv->devlock);
if (ret < 0)
{
ierr("ERROR: nxsem_wait failed: %d\n", ret);
return ret;
}
/* Process the IOCTL by command */
switch (cmd)
{
case TSIOC_SETXRCAL: /* arg: Pointer to int calibration value */
{
FAR int *ptr = (FAR int *)((uintptr_t)arg);
DEBUGASSERT(priv->config != NULL && ptr != NULL);
priv->config->rxplate = *ptr;
}
break;
case TSIOC_GETXRCAL: /* arg: Pointer to int calibration value */
{
FAR int *ptr = (FAR int *)((uintptr_t)arg);
DEBUGASSERT(priv->config != NULL && ptr != NULL);
*ptr = priv->config->rxplate;
}
break;
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 = *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;
}
nxmutex_unlock(&priv->devlock);
return ret;
}
/****************************************************************************
* Name: tsc2007_poll
****************************************************************************/
static int tsc2007_poll(FAR struct file *filep, FAR struct pollfd *fds,
bool setup)
{
FAR struct inode *inode;
FAR struct tsc2007_dev_s *priv;
int ret;
int i;
iinfo("setup: %d\n", (int)setup);
DEBUGASSERT(fds);
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
priv = inode->i_private;
/* Are we setting up the poll? Or tearing it down? */
ret = nxmutex_lock(&priv->devlock);
if (ret < 0)
{
ierr("ERROR: nxsem_wait failed: %d\n", ret);
return ret;
}
if (setup)
{
/* Ignore waits that do not include POLLIN */
if ((fds->events & POLLIN) == 0)
{
ierr("ERROR: Missing POLLIN: revents: %08" PRIx32 "\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_TSC2007_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_TSC2007_NPOLLWAITERS)
{
ierr("ERROR: No available 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)
{
poll_notify(&fds, 1, POLLIN);
}
}
else if (fds->priv)
{
/* This is a request to tear down the poll. */
FAR struct pollfd **slot = (FAR struct pollfd **)fds->priv;
DEBUGASSERT(slot != NULL);
/* Remove all memory of the poll setup */
*slot = NULL;
fds->priv = NULL;
}
errout:
nxmutex_unlock(&priv->devlock);
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: tsc2007_register
*
* Description:
* Configure the TSC2007 to use the provided I2C device instance. This
* will register the driver as /dev/inputN where N is the minor device
* number
*
* Input Parameters:
* dev - An I2C driver instance
* config - Persistent board configuration data
* 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 tsc2007_register(FAR struct i2c_master_s *dev,
FAR struct tsc2007_config_s *config, int minor)
{
FAR struct tsc2007_dev_s *priv;
char devname[DEV_NAMELEN];
#ifdef CONFIG_TSC2007_MULTIPLE
irqstate_t flags;
#endif
int ret;
iinfo("dev: %p minor: %d\n", dev, minor);
/* Debug-only sanity checks */
DEBUGASSERT(dev != NULL && config != NULL && minor >= 0 && minor < 100);
DEBUGASSERT((config->address & 0xfc) == 0x48);
DEBUGASSERT(config->attach != NULL && config->enable != NULL &&
config->clear != NULL && config->pendown != NULL);
/* Create and initialize a TSC2007 device driver instance */
#ifndef CONFIG_TSC2007_MULTIPLE
priv = &g_tsc2007;
#else
priv = (FAR struct tsc2007_dev_s *)
kmm_malloc(sizeof(struct tsc2007_dev_s));
if (!priv)
{
ierr("ERROR: kmm_malloc(%d) failed\n", sizeof(struct tsc2007_dev_s));
return -ENOMEM;
}
#endif
/* Initialize the TSC2007 device driver instance */
memset(priv, 0, sizeof(struct tsc2007_dev_s));
priv->i2c = dev; /* Save the I2C device handle */
priv->config = config; /* Save the board configuration */
nxmutex_init(&priv->devlock); /* Initialize device structure mutex */
nxsem_init(&priv->waitsem, 0, 0); /* Initialize pen event wait semaphore */
/* Make sure that interrupts are disabled */
config->clear(config);
config->enable(config, false);
/* Attach the interrupt handler */
ret = config->attach(config, tsc2007_interrupt);
if (ret < 0)
{
ierr("ERROR: Failed to attach interrupt\n");
goto errout_with_priv;
}
/* Power down the ADC and enable PENIRQ. This is the normal state while
* waiting for a touch event.
*/
ret = tsc2007_transfer(priv, TSC2007_ENABLE_PENIRQ);
if (ret < 0)
{
ierr("ERROR: tsc2007_transfer failed: %d\n", ret);
goto errout_with_priv;
}
/* Register the device as an input device */
snprintf(devname, sizeof(devname), DEV_FORMAT, minor);
iinfo("Registering %s\n", devname);
ret = register_driver(devname, &g_tsc2007_fops, 0666, priv);
if (ret < 0)
{
ierr("ERROR: register_driver() failed: %d\n", ret);
goto errout_with_priv;
}
/* If multiple TSC2007 devices are supported, then we will need to add
* this new instance to a list of device instances so that it can be
* found by the interrupt handler based on the received IRQ number.
*/
#ifdef CONFIG_TSC2007_MULTIPLE
flags = enter_critical_section();
priv->flink = g_tsc2007list;
g_tsc2007list = priv;
leave_critical_section(flags);
#endif
/* Schedule work to perform the initial sampling and to set the data
* availability conditions.
*/
ret = work_queue(HPWORK, &priv->work, tsc2007_worker, priv, 0);
if (ret != 0)
{
ierr("ERROR: Failed to queue work: %d\n", ret);
goto errout_with_priv;
}
/* And return success (?) */
return OK;
errout_with_priv:
nxmutex_destroy(&priv->devlock);
nxsem_destroy(&priv->waitsem);
#ifdef CONFIG_TSC2007_MULTIPLE
kmm_free(priv);
#endif
return ret;
}
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