ADS7843 update

Same changes as the XPT2046

1 files changed, 237 insertions, 146 deletions

diff --git a/drivers/touchpad/ADS7843/touchpad_lld.c b/drivers/touchpad/ADS7843/touchpad_lld.c
index 8fc334b2..77e42133 100644
--- a/drivers/touchpad/ADS7843/touchpad_lld.c
+++ b/drivers/touchpad/ADS7843/touchpad_lld.c
@@ -1,146 +1,237 @@
-/*

-    ChibiOS-LCD-Driver - Copyright (C) 2012

-                 Joel Bodenmann aka Tectu <joel@unormal.org>

-

-    This file is part of ChibiOS-LCD-Driver.

-

-    ChibiOS-LCD-Driver is free software; you can redistribute it and/or modify

-    it under the terms of the GNU General Public License as published by

-    the Free Software Foundation; either version 3 of the License, or

-    (at your option) any later version.

-

-    ChibiOS-LCD-Driver is distributed in the hope that it will be useful,

-    but WITHOUT ANY WARRANTY; without even the implied warranty of

-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-    GNU General Public License for more details.

-

-    You should have received a copy of the GNU General Public License

-    along with this program.  If not, see <http://www.gnu.org/licenses/>.

-*/

-

-/**

- * @file    touchpadADS7843/touchpad_lld.c

- * @brief   Touchpad Driver subsystem low level driver source.

- *

- * @addtogroup TOUCHPAD

- * @{

- */

-

-#include "ch.h"

-#include "hal.h"

-#include "touchpad.h"

-

-#if HAL_USE_TOUCHPAD || defined(__DOXYGEN__)

-

-/*===========================================================================*/

-/* Driver local definitions.                                                 */

-/*===========================================================================*/

-

-#define TP_CS_HIGH      palSetPad(TP_CS_PORT, TP_CS)

-#define TP_CS_LOW       palClearPad(TP_CS_PORT, TP_CS)

-

-#ifdef UNUSED

-#elif defined(__GNUC__)

-# define UNUSED(x) UNUSED_ ## x __attribute__((unused))

-#elif defined(__LCLINT__)

-# define UNUSED(x) /*@unused@*/ x

-#else

-# define UNUSED(x) x

-#endif

-

-/*===========================================================================*/

-/* Driver exported variables.                                                */

-/*===========================================================================*/

-

-#if !defined(__DOXYGEN__)

-	TOUCHPADDriver Touchpad;

-#endif

-

-/*===========================================================================*/

-/* Driver local variables.                                                   */

-/*===========================================================================*/

-

-/*===========================================================================*/

-/* Driver local functions.                                                   */

-/*===========================================================================*/

-

-/*===========================================================================*/

-/* Driver interrupt handlers.                                                */

-/*===========================================================================*/

-

-/*===========================================================================*/

-/* Driver exported functions.                                                */

-/*===========================================================================*/

-

-/* ---- Required Routines ---- */

-

-/**

- * @brief   Low level Touchpad driver initialization.

- *

- * @notapi

- */

-void tp_lld_init(TOUCHPADDriver *tp) {

-	spiStart(tp->spid, tp->spicfg);

-}

-

-/**

- * @brief   Reads out the X direction.

- *

- * @notapi

- */

-uint16_t tp_lld_read_x(void) {

-    uint8_t txbuf[1];

-    uint8_t rxbuf[2];

-    uint16_t x;

-

-    txbuf[0] = 0xd0;

-    TP_CS_LOW;

-    spiSend(&SPID1, 1, txbuf);

-    spiReceive(&SPID1, 2, rxbuf);

-    TP_CS_HIGH;

-

-    x = rxbuf[0] << 4;

-    x |= rxbuf[1] >> 4;

-

-    return x;

-}

-

-/*

- * @brief	Reads out the Y direction.

- *

- * @notapi

- */

-uint16_t tp_lld_read_y(void) {

-    uint8_t txbuf[1];

-    uint8_t rxbuf[2];

-    uint16_t y;

-

-    txbuf[0] = 0x90;

-    TP_CS_LOW;

-    spiSend(&SPID1, 1, txbuf);

-    spiReceive(&SPID1, 2, rxbuf);

-    TP_CS_HIGH;

-

-    y = rxbuf[0] << 4;

-    y |= rxbuf[1] >> 4;

-

-    return y;

-}

-

-/* ---- Optional Routines ---- */

-#if TOUCHPAD_HAS_IRQ || defined(__DOXYGEN__)

-	/*

-	 * @brief	for checking if touchpad is pressed or not.

-	 *

-	 * @return	1 if pressed / 0 if not pressed

-	 *

-	 * @noapi

-	 */

-	 uint8_t tp_lld_irq(void) {

-		return (!palReadPad(TP_IRQ_PORT, TP_IRQ));

-	}

-#endif

-

-#endif /* HAL_USE_TOUCHPAD */

-/** @} */

-

+/*
+    ChibiOS-LCD-Driver - Copyright (C) 2012
+                 Joel Bodenmann aka Tectu <joel@unormal.org>
+
+    This file is part of ChibiOS-LCD-Driver.
+
+    ChibiOS-LCD-Driver is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    ChibiOS-LCD-Driver is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file    touchpadADS7843/touchpad_lld.c
+ * @brief   Touchpad Driver subsystem low level driver source.
+ *
+ * @addtogroup TOUCHPAD
+ * @{
+ */
+
+#include "ch.h"
+#include "hal.h"
+#include "touchpad.h"
+
+#if HAL_USE_TOUCHPAD || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver local definitions.                                                 */
+/*===========================================================================*/
+
+#ifdef UNUSED
+#elif defined(__GNUC__)
+# define UNUSED(x) UNUSED_ ## x __attribute__((unused))
+#elif defined(__LCLINT__)
+# define UNUSED(x) /*@unused@*/ x
+#else
+# define UNUSED(x) x
+#endif
+
+/*===========================================================================*/
+/* Driver exported variables.                                                */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver local variables.                                                   */
+/*===========================================================================*/
+#if !defined(__DOXYGEN__)
+    /* Local copy of the current touchpad driver */
+    static const TOUCHPADDriver *tpDriver;
+
+    static uint16_t sampleBuf[7];
+#endif
+
+/*===========================================================================*/
+/* Driver local functions.                                                   */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver interrupt handlers.                                                */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver exported functions.                                                */
+/*===========================================================================*/
+
+/* ---- Required Routines ---- */
+
+/**
+ * @brief   Low level Touchpad driver initialization.
+ *
+ * @notapi
+ */
+void tp_lld_init(const TOUCHPADDriver *tp) {
+  tpDriver=tp;
+
+  if (tpDriver->direct_init)
+    spiStart(tpDriver->spip, tpDriver->spicfg);
+}
+
+
+/**
+ * @brief   Reads a conversion from the touchpad
+ *
+ * @param[in] cmd    The command bits to send to the touchpad
+ *
+ * @return  The read value 12-bit right-justified
+ *
+ * @note    This function only reads data, it is assumed that the pins are
+ *          configured properly and the bus has been acquired beforehand
+ *
+ * @notapi
+ */
+uint16_t tp_lld_read_value(uint8_t cmd) {
+  static uint8_t txbuf[3]={0};
+  static uint8_t rxbuf[3]={0};
+  uint16_t ret;
+
+  txbuf[0]=cmd;
+
+  spiExchange(tpDriver->spip, 3, txbuf, rxbuf);
+
+  ret = (rxbuf[1] << 5) | (rxbuf[2] >> 3);
+
+  return ret;
+}
+
+/**
+ * @brief   7-point median filtering code for touchpad samples
+ *
+ * @note    This is an internally used routine only.
+ *
+ * @notapi
+ */
+static void tp_lld_filter(void) {
+  uint16_t temp;
+  int i,j;
+
+  for (i=0; i<4; i++) {
+    for (j=i; j<7; j++) {
+      if (sampleBuf[i] > sampleBuf[j]) {
+        /* Swap the values */
+        temp=sampleBuf[i];
+        sampleBuf[i]=sampleBuf[j];
+        sampleBuf[j]=temp;
+      }
+    }
+  }
+
+}
+
+/**
+ * @brief   Reads out the X direction.
+ *
+ * @note    The samples are median filtered for greater noise reduction
+ *
+ * @notapi
+ */
+uint16_t tp_lld_read_x(void) {
+  int i;
+
+#if defined(SPI_USE_MUTUAL_EXCLUSION)
+  spiAcquireBus(tpDriver->spip);
+#endif
+
+  TOUCHPAD_SPI_PROLOGUE();
+  palClearPad(tpDriver->spicfg->ssport, tpDriver->spicfg->sspad);
+
+  /* Discard the first conversion - very noisy and keep the ADC on hereafter
+   * till we are done with the sampling. Note that PENIRQ is disabled.
+   */
+  tp_lld_read_value(0xD1);
+
+  for (i=0;i<7;i++) {
+    sampleBuf[i]=tp_lld_read_value(0xD1);
+  }
+
+  /* Switch on PENIRQ once again - perform a dummy read */
+  tp_lld_read_value(0xD0);
+
+  palSetPad(tpDriver->spicfg->ssport, tpDriver->spicfg->sspad);
+  TOUCHPAD_SPI_EPILOGUE();
+
+#if defined(SPI_USE_MUTUAL_EXCLUSION)
+  spiReleaseBus(tpDriver->spip);
+#endif
+
+  /* Find the median - use selection sort */
+  tp_lld_filter();
+
+  return sampleBuf[3];
+}
+
+/*
+ * @brief   Reads out the Y direction.
+ *
+ * @notapi
+ */
+uint16_t tp_lld_read_y(void) {
+  int i;
+
+#if defined(SPI_USE_MUTUAL_EXCLUSION)
+  spiAcquireBus(tpDriver->spip);
+#endif
+
+  TOUCHPAD_SPI_PROLOGUE();
+  palClearPad(tpDriver->spicfg->ssport, tpDriver->spicfg->sspad);
+
+  /* Discard the first conversion - very noisy and keep the ADC on hereafter
+   * till we are done with the sampling. Note that PENIRQ is disabled.
+   */
+  tp_lld_read_value(0x91);
+
+  for (i=0;i<7;i++) {
+    sampleBuf[i]=tp_lld_read_value(0x91);
+  }
+
+  /* Switch on PENIRQ once again - perform a dummy read */
+  tp_lld_read_value(0x90);
+
+  palSetPad(tpDriver->spicfg->ssport, tpDriver->spicfg->sspad);
+  TOUCHPAD_SPI_EPILOGUE();
+
+#ifdef SPI_USE_MUTUAL_EXCLUSION
+  spiReleaseBus(tpDriver->spip);
+#endif
+
+  /* Find the median - use selection sort */
+  tp_lld_filter();
+
+  return sampleBuf[3];
+}
+
+/* ---- Optional Routines ---- */
+#if TOUCHPAD_HAS_IRQ || defined(__DOXYGEN__)
+    /*
+     * @brief   for checking if touchpad is pressed or not.
+     *
+     * @return  1 if pressed / 0 if not pressed
+     *
+     * @notapi
+     */
+     uint8_t tp_lld_irq(void) {
+        return (!palReadPad(tpDriver->tpIRQPort, tpDriver->tpIRQPin));
+    }
+#endif
+
+#endif /* HAL_USE_TOUCHPAD */
+/** @} */
+