Add hooks for the ADS7843E touchscreen controller

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4013 42af7a65-404d-4744-a932-0658087f49c3

5 files changed, 1115 insertions, 4 deletions

diff --git a/nuttx/drivers/input/Make.defs b/nuttx/drivers/input/Make.defs
index e4758ed84..e32dc4549 100755
--- a/nuttx/drivers/input/Make.defs
+++ b/nuttx/drivers/input/Make.defs
@@ -37,12 +37,16 @@
 
 ifeq ($(CONFIG_INPUT),y)
 
-# Include the TI TSC2007 drivers
+# Include the selected touchscreen drivers
 
 ifeq ($(CONFIG_INPUT_TSC2007),y)
   CSRCS += tsc2007.c
 endif
 
+ifeq ($(CONFIG_INPUT_ADS7843E),y)
+  CSRCS += ads7843e.c
+endif
+
 # Include input device driver build support
 
 DEPPATH += --dep-path input
diff --git a/nuttx/drivers/input/ads7843e.c b/nuttx/drivers/input/ads7843e.c
new file mode 100644
index 000000000..d03a64b44
--- /dev/null
+++ b/nuttx/drivers/input/ads7843e.c
@@ -0,0 +1,1037 @@
+/****************************************************************************
+ * drivers/input/ads7843e.c
+ *
+ *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * References:
+ *   "Touch Screen Controller, ADS7843," Burr-Brown Products from Texas
+ *    Instruments, SBAS090B, September 2000, Revised May 2002"
+ *
+ * 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.h>
+#include <nuttx/spi.h>
+#include <nuttx/wqueue.h>
+
+#include <nuttx/input/touchscreen.h>
+#include <nuttx/input/ads7843e.h>
+
+#include "ads7843e.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+/* Configuration ************************************************************/
+/* Reference counting is partially implemented, but not needed in the
+ * current design.
+ */
+
+#undef CONFIG_ADS7843E_REFCNT
+
+/* 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
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/* This describes the state of one contact */
+
+enum ads7843e_contact_3
+{
+  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 ADS7843E sample */
+
+struct ads7843e_sample_s
+{
+  uint8_t  id;                          /* Sampled touch point ID */
+  uint8_t  contact;                     /* Contact state (see enum ads7843e_contact_e) */
+  uint16_t x;                           /* Measured X position */
+  uint16_t y;                           /* Measured Y position */
+#warning "Missing other measurement data" /* Like size and pressure */
+};
+
+/* This structure describes the state of one ADS7843E driver instance */
+
+struct ads7843e_dev_s
+{
+#ifdef CONFIG_ADS7843E_MULTIPLE
+  FAR struct ads7843e_dev_s *flink;     /* Supports a singly linked list of drivers */
+#endif
+#ifdef CONFIG_ADS7843E_REFCNT
+  uint8_t crefs;                        /* Number of times the device has been opened */
+#endif
+  uint8_t nwaiters;                     /* Number of threads waiting for ADS7843E data */
+  uint8_t id;                           /* Current touch point ID */
+  volatile bool penchange;              /* An unreported event is buffered */
+  sem_t devsem;                         /* Manages exclusive access to this structure */
+  sem_t waitsem;                        /* Used to wait for the availability of data */
+
+  FAR struct ads7843e_config_s *config; /* Board configuration data */
+  FAR struct spi_dev_s *spi;            /* Saved SPI driver instance */
+  struct work_s work;                   /* Supports the interrupt handling "bottom half" */
+  struct ads7843e_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'.
+   */
+
+#ifndef CONFIG_DISABLE_POLL
+  struct pollfd *fds[CONFIG_ADS7843E_NPOLLWAITERS];
+#endif
+};
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static void ads7843e_notify(FAR struct ads7843e_dev_s *priv);
+static int ads7843e_sample(FAR struct ads7843e_dev_s *priv,
+                           FAR struct ads7843e_sample_s *sample);
+static int ads7843e_waitsample(FAR struct ads7843e_dev_s *priv,
+                               FAR struct ads7843e_sample_s *sample);
+static int ads7843e_transfer(FAR struct ads7843e_dev_s *priv, uint8_t cmd);
+static void ads7843e_worker(FAR void *arg);
+static int ads7843e_interrupt(int irq, FAR void *context);
+
+/* Character driver methods */
+
+static int ads7843e_open(FAR struct file *filep);
+static int ads7843e_close(FAR struct file *filep);
+static ssize_t ads7843e_read(FAR struct file *filep, FAR char *buffer, size_t len);
+static int ads7843e_ioctl(FAR struct file *filep, int cmd, unsigned long arg);
+#ifndef CONFIG_DISABLE_POLL
+static int ads7843e_poll(FAR struct file *filep, struct pollfd *fds, bool setup);
+#endif
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/* This the the vtable that supports the character driver interface */
+
+static const struct file_operations ads7843e_fops =
+{
+  ads7843e_open,    /* open */
+  ads7843e_close,   /* close */
+  ads7843e_read,    /* read */
+  0,                /* write */
+  0,                /* seek */
+  ads7843e_ioctl    /* ioctl */
+#ifndef CONFIG_DISABLE_POLL
+  , ads7843e_poll   /* poll */
+#endif
+};
+
+/* If only a single ADS7843E device is supported, then the driver state
+ * structure may as well be pre-allocated.
+ */
+
+#ifndef CONFIG_ADS7843E_MULTIPLE
+static struct ads7843e_dev_s g_ads7843e;
+
+/* Otherwise, we will need to maintain allocated driver instances in a list */
+
+#else
+static struct ads7843e_dev_s *g_ads7843elist;
+#endif
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: ads7843e_notify
+ ****************************************************************************/
+
+static void ads7843e_notify(FAR struct ads7843e_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 ADS7843E
+       * is no longer avaialable.
+       */
+
+      sem_post(&priv->waitsem); 
+    }
+
+  /* If there are threads waiting on poll() for ADS7843E data to become availabe,
+   * 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_ADS7843E_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: ads7843e_sample
+ ****************************************************************************/
+
+static int ads7843e_sample(FAR struct ads7843e_dev_s *priv,
+                          FAR struct ads7843e_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 ADS7843E 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 ads7843e_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: ads7843e_waitsample
+ ****************************************************************************/
+
+static int ads7843e_waitsample(FAR struct ads7843e_dev_s *priv,
+                               FAR struct ads7843e_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->devsem);
+
+  /* Try to get the a sample... if we cannot, then wait on the semaphore
+   * that is posted when new sample data is availble.
+   */
+
+  while (ads7843e_sample(priv, sample) < 0)
+    {
+      /* Wait for a change in the ADS7843E 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->devsem);
+
+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 ADS7843E for some reason, the data
+   * might be read out of order.
+   */
+
+  sched_unlock();
+  return ret;
+}
+
+/****************************************************************************
+ * Name: ads7843e_transfer
+ ****************************************************************************/
+
+static int ads7843e_transfer(FAR struct ads7843e_dev_s *priv, uint8_t cmd)
+{
+  int ret = 0;
+#warning "Missing logic"
+  ivdbg("data: 0x%04x\n", ret);
+  return ret;
+}
+
+/****************************************************************************
+ * Name: ads7843e_worker
+ ****************************************************************************/
+
+static void ads7843e_worker(FAR void *arg)
+{
+  FAR struct ads7843e_dev_s    *priv = (FAR struct ads7843e_dev_s *)arg;
+  FAR struct ads7843e_config_s *config;   /* Convenience pointer */
+  bool                         pendown;  /* true: pend is down */
+  uint16_t                     x;        /* X position */
+  uint16_t                     y;        /* Y position */
+#warning "Missing other measurement data" /* Like size and pressure */
+
+  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 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;
+        }
+    }
+  else
+    {
+      /* Handle all pen down events.  First, sample positional values. */
+
+#warning "Missing logic"
+
+      /* Save the measurements */
+
+      priv->sample.x        = x;
+      priv->sample.y        = y;
+#warning "Missing other measurement data" /* Like size and pressure */
+    }
+
+  /* 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 ADS7843E data is available */
+
+  ads7843e_notify(priv);
+
+  /* Exit, re-enabling ADS7843E interrupts */
+
+errout:
+  config->enable(config, true);
+}
+
+/****************************************************************************
+ * Name: ads7843e_interrupt
+ ****************************************************************************/
+
+static int ads7843e_interrupt(int irq, FAR void *context)
+{
+  FAR struct ads7843e_dev_s    *priv;
+  FAR struct ads7843e_config_s *config;
+  int                          ret;
+
+  /* Which ADS7843E device caused the interrupt? */
+
+#ifndef CONFIG_ADS7843E_MULTIPLE
+  priv = &g_ads7843e;
+#else
+  for (priv = g_ads7843elist;
+       priv && priv->configs->irq != irq;
+       priv = priv->flink);
+
+  ASSERT(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 ADS7843E 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(&priv->work, ads7843e_worker, priv, 0);
+  if (ret != 0)
+    {
+      illdbg("Failed to queue work: %d\n", ret);
+    }
+
+  /* Clear any pending interrupts and return success */
+
+  config->clear(config);
+  return OK;
+}
+
+/****************************************************************************
+ * Name: ads7843e_open
+ ****************************************************************************/
+
+static int ads7843e_open(FAR struct file *filep)
+{
+#ifdef CONFIG_ADS7843E_REFCNT
+  FAR struct inode         *inode;
+  FAR struct ads7843e_dev_s *priv;
+  uint8_t                   tmp;
+  int                       ret;
+
+  DEBUGASSERT(filep);
+  inode = filep->f_inode;
+
+  DEBUGASSERT(inode && inode->i_private);
+  priv  = (FAR struct ads7843e_dev_s *)inode->i_private;
+
+  /* Get exclusive access to the driver data structure */
+
+  ret = sem_wait(&priv->devsem);
+  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->devsem);
+  return ret;
+#else
+  return OK;
+#endif
+}
+
+/****************************************************************************
+ * Name: ads7843e_close
+ ****************************************************************************/
+
+static int ads7843e_close(FAR struct file *filep)
+{
+#ifdef CONFIG_ADS7843E_REFCNT
+  FAR struct inode         *inode;
+  FAR struct ads7843e_dev_s *priv;
+  int                       ret;
+
+  DEBUGASSERT(filep);
+  inode = filep->f_inode;
+
+  DEBUGASSERT(inode && inode->i_private);
+  priv  = (FAR struct ads7843e_dev_s *)inode->i_private;
+
+  /* Get exclusive access to the driver data structure */
+
+  ret = sem_wait(&priv->devsem);
+  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->devsem);
+#endif
+  return OK;
+}
+
+/****************************************************************************
+ * Name: ads7843e_read
+ ****************************************************************************/
+
+static ssize_t ads7843e_read(FAR struct file *filep, FAR char *buffer, size_t len)
+{
+  FAR struct inode          *inode;
+  FAR struct ads7843e_dev_s  *priv;
+  FAR struct touch_sample_s *report;
+  struct ads7843e_sample_s    sample;
+  int                        ret;
+
+  DEBUGASSERT(filep);
+  inode = filep->f_inode;
+
+  DEBUGASSERT(inode && inode->i_private);
+  priv  = (FAR struct ads7843e_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->devsem);
+  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 = ads7843e_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 = ads7843e_waitsample(priv, &sample);
+      if (ret < 0)
+        {
+          /* We might have been awakened by a signal */
+
+          goto errout;
+        }
+    }
+
+  /* In any event, we now have sampled ADS7843E 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  = 42; /* ???????????????????? */
+
+  /* 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 | TOUCH_PRESSURE_VALID;
+    }
+  else /* if (sample->contact == CONTACT_MOVE) */
+    {
+      /* Movement of the same contact */
+
+      report->point[0].flags  = TOUCH_MOVE | TOUCH_ID_VALID | TOUCH_POS_VALID | TOUCH_PRESSURE_VALID;
+    }
+
+  ret = SIZEOF_TOUCH_SAMPLE_S(1);
+
+errout:
+  sem_post(&priv->devsem);
+  return ret;
+}
+
+/****************************************************************************
+ * Name:ads7843e_ioctl
+ ****************************************************************************/
+
+static int ads7843e_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
+{
+  FAR struct inode         *inode;
+  FAR struct ads7843e_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 ads7843e_dev_s *)inode->i_private;
+
+  /* Get exclusive access to the driver data structure */
+
+  ret = sem_wait(&priv->devsem);
+  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_SETCALIB:  /* arg: Pointer to int calibration value */
+        {
+          FAR int *ptr = (FAR int *)((uintptr_t)arg);
+          DEBUGASSERT(priv->config != NULL && ptr != NULL);
+          priv->config->calib = *ptr;
+        }
+        break;
+
+      case TSIOC_GETCALIB:  /* arg: Pointer to int calibration value */
+        {
+          FAR int *ptr = (FAR int *)((uintptr_t)arg);
+          DEBUGASSERT(priv->config != NULL && ptr != NULL);
+          *ptr = priv->config->calib;
+        }
+        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 = SPI_SETFREQUENCY(priv->spi, *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->devsem);
+  return ret;
+}
+
+/****************************************************************************
+ * Name: ads7843e_poll
+ ****************************************************************************/
+
+#ifndef CONFIG_DISABLE_POLL
+static int ads7843e_poll(FAR struct file *filep, FAR struct pollfd *fds,
+                        bool setup)
+{
+  FAR struct inode         *inode;
+  FAR struct ads7843e_dev_s *priv;
+  pollevent_t               eventset;
+  int                       ndx;
+  int                       ret = OK;
+  int                       i;
+
+  ivdbg("setup: %d\n", (int)setup);
+  DEBUGASSERT(filep && fds);
+  inode = filep->f_inode;
+
+  DEBUGASSERT(inode && inode->i_private);
+  priv  = (FAR struct ads7843e_dev_s *)inode->i_private;
+
+  /* Are we setting up the poll?  Or tearing it down? */
+
+  ret = sem_wait(&priv->devsem);
+  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->revents & POLLIN) == 0)
+        {
+          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_ADS7843E_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_ADS7843E_NPOLLWAITERS)
+        {
+          fds->priv    = NULL;
+          ret          = -EBUSY;
+          goto errout;
+        }
+
+      /* Should we immediately notify on any of the requested events? */
+
+      if (priv->penchange)
+        {
+          ads7843e_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->devsem);
+  return ret;
+}
+#endif
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: ads7843e_register
+ *
+ * Description:
+ *   Configure the ADS7843E to use the provided SPI device instance.  This
+ *   will register the driver as /dev/inputN where N is the minor device
+ *   number
+ *
+ * Input Parameters:
+ *   dev     - An SPI driver instance
+ *   config  - Persistant 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 ads7843e_register(FAR struct spi_dev_s *dev,
+                      FAR struct ads7843e_config_s *config, int minor)
+{
+  FAR struct ads7843e_dev_s *priv;
+  char devname[DEV_NAMELEN];
+#ifdef CONFIG_ADS7843E_MULTIPLE
+  irqstate_t flags;
+#endif
+  int ret;
+
+  ivdbg("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 ADS7843E device driver instance */
+
+#ifndef CONFIG_ADS7843E_MULTIPLE
+  priv = &g_ads7843e;
+#else
+  priv = (FAR struct ads7843e_dev_s *)kmalloc(sizeof(struct ads7843e_dev_s));
+  if (!priv)
+    {
+      idbg("kmalloc(%d) failed\n", sizeof(struct ads7843e_dev_s));
+      return -ENOMEM;
+    }
+#endif
+
+  /* Initialize the ADS7843E device driver instance */
+
+  memset(priv, 0, sizeof(struct ads7843e_dev_s));
+  priv->spi    = dev;             /* Save the SPI device handle */
+  priv->config = config;          /* Save the board configuration */
+  sem_init(&priv->devsem,  0, 1); /* Initialize device structure semaphore */
+  sem_init(&priv->waitsem, 0, 0); /* Initialize pen event wait semaphore */
+
+  /* Set the SPI frequency (saving the actual frequency) */
+
+  config->frequency = SPI_SETFREQUENCY(dev, config->frequency);
+
+  /* Make sure that interrupts are disabled */
+
+  config->clear(config);
+  config->enable(config, false);
+
+  /* Attach the interrupt handler */
+
+  ret = config->attach(config, ads7843e_interrupt);
+  if (ret < 0)
+    {
+      idbg("Failed to attach interrupt\n");
+      goto errout_with_priv;
+    }
+
+  /* Initialize the touchscreen device */
+#warning "Missing logic"
+
+  /* Register the device as an input device */
+
+  (void)snprintf(devname, DEV_NAMELEN, DEV_FORMAT, minor);
+  ivdbg("Registering %s\n", devname);
+
+  ret = register_driver(devname, &ads7843e_fops, 0666, priv);
+  if (ret < 0)
+    {
+      idbg("register_driver() failed: %d\n", ret);
+      goto errout_with_priv;
+    }
+
+  /* If multiple ADS7843E 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 recieved IRQ number.
+   */
+
+#ifdef CONFIG_ADS7843E_MULTIPLE
+  priv->flink    = g_ads7843elist;
+  g_ads7843elist = priv;
+  irqrestore(flags);
+#endif
+
+  /* Schedule work to perform the initial sampling and to set the data
+   * availability conditions.
+   */
+
+  ret = work_queue(&priv->work, ads7843e_worker, priv, 0);
+  if (ret != 0)
+    {
+      idbg("Failed to queue work: %d\n", ret);
+      goto errout_with_priv;
+    }
+
+  /* And return success (?) */
+
+  return OK;
+
+errout_with_priv:
+  sem_destroy(&priv->devsem);
+#ifdef CONFIG_ADS7843E_MULTIPLE
+  kfree(priv);
+#endif
+  return ret;
+}
diff --git a/nuttx/drivers/input/ads7843e.h b/nuttx/drivers/input/ads7843e.h
new file mode 100644
index 000000000..80106c3b8
--- /dev/null
+++ b/nuttx/drivers/input/ads7843e.h
@@ -0,0 +1,71 @@
+/********************************************************************************************
+ * drivers/input/ads7843e.h
+ *
+ *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * References:
+ *   "Touch Screen Controller, ADS7843," Burr-Brown Products from Texas
+ *    Instruments, SBAS090B, September 2000, Revised May 2002"
+ *
+ * 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.
+ *
+ ********************************************************************************************/
+
+#ifndef __DRIVERS_INPUT_ADS7843E_H
+#define __DRIVERS_INPUT_ADS7843E_H
+
+/********************************************************************************************
+ * Included Files
+ ********************************************************************************************/
+
+/********************************************************************************************
+ * Pre-Processor Definitions
+ ********************************************************************************************/
+
+/********************************************************************************************
+ * Public Types
+ ********************************************************************************************/
+
+/********************************************************************************************
+ * Public Function Prototypes
+ ********************************************************************************************/
+
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C" {
+#else
+#define EXTERN extern
+#endif
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __DRIVERS_INPUT_ADS7843E_H */
diff --git a/nuttx/drivers/input/tsc2007.c b/nuttx/drivers/input/tsc2007.c
index 25c748823..e6e570d62 100644
--- a/nuttx/drivers/input/tsc2007.c
+++ b/nuttx/drivers/input/tsc2007.c
@@ -2,7 +2,7 @@
  * drivers/input/tsc2007.c
  *
  *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * References:
  *   "1.2V to 3.6V, 12-Bit, Nanopower, 4-Wire Micro TOUCH SCREEN CONTROLLER
@@ -1187,7 +1187,6 @@ int tsc2007_register(FAR struct i2c_dev_s *dev,
    */
 
 #ifdef CONFIG_TSC2007_MULTIPLE
-  priv          = irqsave;
   priv->flink   = g_tsc2007list;
   g_tsc2007list = priv;
   irqrestore(flags);
diff --git a/nuttx/drivers/input/tsc2007.h b/nuttx/drivers/input/tsc2007.h
index 067d6ba3b..052ce76d2 100644
--- a/nuttx/drivers/input/tsc2007.h
+++ b/nuttx/drivers/input/tsc2007.h
@@ -2,7 +2,7 @@
  * drivers/input/tsc2007.h
  *
  *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * References:
  *   "1.2V to 3.6V, 12-Bit, Nanopower, 4-Wire Micro TOUCH SCREEN CONTROLLER