SSP driver fixes for the LPC178x; Fixes for Open1788 touchscreen driver

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5812 42af7a65-404d-4744-a932-0658087f49c3

arch/arm/src/armv6-m/Toolchain.defs

@@ -160,6 +160,6 @@ endif
 ifeq ($(CONFIG_ARMV6M_TOOLCHAIN),GNU_EABI)
   CROSSDEV ?= arm-none-eabi-
   ARCROSSDEV ?= arm-none-eabi-
-  MAXOPTIMIZATION = -O3
+  MAXOPTIMIZATION = -Os
   ARCHCPUFLAGS = -mcpu=cortex-m0 -mthumb -march=armv6-m -mfloat-abi=soft
 endif  

arch/arm/src/lpc17xx/chip/lpc17_ssp.h

@@ -89,6 +89,17 @@
 #define LPC17_SSP1_ICR          (LPC17_SSP1_BASE+LPC17_SSP_ICR_OFFSET)
 #define LPC17_SSP1_DMACR        (LPC17_SSP1_BASE+LPC17_SSP_DMACR_OFFSET)
 
+#define LPC17_SSP2_CR0          (LPC17_SSP2_BASE+LPC17_SSP_CR0_OFFSET)
+#define LPC17_SSP2_CR1          (LPC17_SSP2_BASE+LPC17_SSP_CR1_OFFSET)
+#define LPC17_SSP2_DR           (LPC17_SSP2_BASE+LPC17_SSP_DR_OFFSET)
+#define LPC17_SSP2_SR           (LPC17_SSP2_BASE+LPC17_SSP_SR_OFFSET)
+#define LPC17_SSP2_CPSR         (LPC17_SSP2_BASE+LPC17_SSP_CPSR_OFFSET)
+#define LPC17_SSP2_IMSC         (LPC17_SSP2_BASE+LPC17_SSP_IMSC_OFFSET)
+#define LPC17_SSP2_RIS          (LPC17_SSP2_BASE+LPC17_SSP_RIS_OFFSET)
+#define LPC17_SSP2_MIS          (LPC17_SSP2_BASE+LPC17_SSP_MIS_OFFSET)
+#define LPC17_SSP2_ICR          (LPC17_SSP2_BASE+LPC17_SSP_ICR_OFFSET)
+#define LPC17_SSP2_DMACR        (LPC17_SSP2_BASE+LPC17_SSP_DMACR_OFFSET)
+
 /* Register bit definitions *********************************************************/
 /* Control Register 0 */
 

arch/arm/src/lpc17xx/lpc17_gpio.c

@@ -52,7 +52,6 @@
 #include "chip.h"
 #include "lpc17_gpio.h"
 
-
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/

arch/arm/src/lpc17xx/lpc17_ssp.c

@@ -92,6 +92,7 @@
 #endif
 
 /* SSP Clocking *************************************************************/
+
 #if defined(LPC176x)
 /* The CPU clock by 1, 2, 4, or 8 to get the SSP peripheral clock (SSP_CLOCK).
  * SSP_CLOCK may be further divided by 2-254 to get the SSP clock.  If we
@@ -106,17 +107,16 @@
 
 #  if LPC17_CCLK > 100000000
 #    error "CCLK <= 100,000,000 assumed"
-# endif
+#  endif
 
 #  define SSP_PCLKSET_DIV    SYSCON_PCLKSEL_CCLK
 #  define SSP_CLOCK          LPC17_CCLK
 
+#elif defined(LPC178x)
 /* All peripherals are clocked by the same peripheral clock in the LPC178x
  * family.
  */
 
-#elif defined(LPC178x)
-
 #  define SSP_CLOCK          BOARD_PCLK_FREQUENCY
 
 #endif
@@ -397,10 +397,12 @@ static int ssp_lock(FAR struct spi_dev_s *dev, bool lock)
 static uint32_t ssp_setfrequency(FAR struct spi_dev_s *dev, uint32_t frequency)
 {
   FAR struct lpc17_sspdev_s *priv = (FAR struct lpc17_sspdev_s *)dev;
-  uint32_t divisor;
+  uint32_t cpsdvsr;
+  uint32_t scr;
+  uint32_t regval;
   uint32_t actual;
 
-  /* Check if the requested frequence is the same as the frequency selection */
+  /* Check if the requested frequency is the same as the frequency selection */
 
   DEBUGASSERT(priv && frequency <= SSP_CLOCK / 2);
 #ifndef CONFIG_SPI_OWNBUS
@@ -412,30 +414,65 @@ static uint32_t ssp_setfrequency(FAR struct spi_dev_s *dev, uint32_t frequency)
     }
 #endif
 
-  /* frequency = SSP_CLOCK / divisor, or divisor = SSP_CLOCK / frequency */
+  /* The SSP bit frequency is given by:
+   *
+   *   frequency = SSP_CLOCK / (CPSDVSR * (SCR+1)).
+   *
+   * Let's try for a solution with the smallest value of SCR.  NOTES:
+   * (1) In the calculations below, the value of the variable 'scr' is
+   * (SCR+1) in the above equation. (2) On slower LPC17xx parts, SCR
+   * will probably always be zero.
+   */
 
-  divisor = SSP_CLOCK / frequency;
+  for (scr = 1; scr <= 256; scr++)
-
-   /* "In master mode, CPSDVSRmin = 2 or larger (even numbers only)" */
-
-  if (divisor < 2)
     {
-      divisor = 2;
+      /* CPSDVSR = SSP_CLOCK / (SCR + 1) / frequency */
-    }
+
-  else if (divisor > 254)
+      cpsdvsr = SSP_CLOCK / (scr * frequency);
-    {
+
-      divisor = 254;
+      /* Break out on the first solution we find with the smallest value
+       * of SCR and with CPSDVSR within the maximum range or 254.
+       */
+
+      if (cpsdvsr < 255)
+        {
+          break;
+        }
     }
 
-  divisor = (divisor + 1) & ~1;
+  DEBUGASSERT(scr <= 256 && cpsdvsr <= 255);
 
-  /* Save the new divisor value */
+  /* "In master mode, CPSDVSRmin = 2 or larger (even numbers only)" */
+
+  if (cpsdvsr < 2)
+    {
+      /* Clip to the minimum value. */
+
+      cpsdvsr = 2;
+    }
+  else if (cpsdvsr > 254)
+    {
+      /* This should never happen */
+
+      cpsdvsr = 254;
+    }
+
+  /* Force even */
+
+  cpsdvsr = (cpsdvsr + 1) & ~1;
+
+  /* Save the new CPSDVSR and SCR values */
   
-  ssp_putreg(priv, LPC17_SSP_CPSR_OFFSET, divisor);
+  ssp_putreg(priv, LPC17_SSP_CPSR_OFFSET, cpsdvsr);
+
+  regval  = ssp_getreg(priv, LPC17_SSP_CR0_OFFSET);
+  regval &= ~SSP_CR0_SCR_MASK;
+  regval |= ((scr - 1) << SSP_CR0_SCR_SHIFT);
+  ssp_putreg(priv, LPC17_SSP_CR0_OFFSET, regval);
 
   /* Calculate the new actual */
 
-  actual = SSP_CLOCK / divisor;
+  actual = SSP_CLOCK / (cpsdvsr * scr);
 
   /* Save the frequency setting */
 

configs/open1788/README.txt

@@ -453,10 +453,11 @@ CONFIGURATION
        following ways:
 
        CONFIG_INPUT=y                      : Enable support for input devices
-       CONFIG_GPIO_IRQ=y                   : GPIO interrupt support
        CONFIG_INPUT_ADS7843E=y             : Enable support for the XPT2048
+       CONFIG_ADS7843E_SPIDEV=1            : Use SSP1 for communication
        CONFIG_SPI=y                        : Enable SPI support
        CONFIG_SPI_EXCHANGE=n               : exchange() method is not supported
+       CONFIG_GPIO_IRQ=y                   : GPIO interrupt support
        CONFIG_LPC17_SSP1=y                 : Enable support for SSP1
        CONFIG_EXAMPLES_TOUCHSCREEN=y       : Enable the touchscreen built-int test
        CONFIG_EXAMPLES_TOUCHSCREEN_BUILTIN=y
@@ -466,7 +467,8 @@ CONFIGURATION
        You will also have to disable SD card support to use this test.  The
        SD card detect (CD) signal is on P0[13].  This signal is shared.  It
        is also used for MOSI1 and USB_UP_LED.  The CD pin may be disconnected.
-       There is a jumper on board that enables the CD pin.
+       There is a jumper on board that enables the CD pin.  OR, you can simply
+       remove the SD module so that it does not drive the CD pin.
 
        CONFIG_LPC17_GPDMA=n                : No DMA
        CONFIG_ARCH_DMA=n

configs/open1788/include/board.h

@@ -407,12 +407,6 @@
 #define GPIO_SSP1_MOSI   GPIO_SSP1_MOSI_2
 #define GPIO_SSP1_SCK    GPIO_SSP1_SCK_2
 
-#define GPIO_SSP1_SSEL_1   (GPIO_ALT2 | GPIO_PULLUP | GPIO_PORT0 | GPIO_PIN6)
-#define GPIO_SSP1_SSEL_2   (GPIO_ALT2 | GPIO_PULLUP | GPIO_PORT0 | GPIO_PIN14)
-#define GPIO_SSP1_SSEL_3   (GPIO_ALT5 | GPIO_PULLUP | GPIO_PORT1 | GPIO_PIN26)
-#define GPIO_SSP1_SSEL_4   (GPIO_ALT3 | GPIO_PULLUP | GPIO_PORT4 | GPIO_PIN21)
-
-
 /************************************************************************************
  * Public Types
  ************************************************************************************/

configs/open1788/src/lpc17_ssp.c

@@ -174,7 +174,7 @@ void  lpc17_ssp1select(FAR struct spi_dev_s *dev, enum spi_dev_e devid, bool sel
   sspdbg("devid: %d CS: %s\n", (int)devid, selected ? "assert" : "de-assert");
   if (devid == SPIDEV_TOUCHSCREEN)
     {
-      /* Assert/de-assert the CS pin to the card */
+      /* Assert/de-assert the CS pin to the touchscreen */
 
       ssp_dumpgpio(GPIO_TC_CS, "lpc17_ssp1select() Entry");
       lpc17_gpiowrite(GPIO_TC_CS, !selected);

configs/open1788/src/lpc17_touchscreen.c

@@ -80,17 +80,27 @@
 #endif
 
 #ifndef CONFIG_ADS7843E_SPIDEV
-#  define CONFIG_ADS7843E_SPIDEV 3
+#  define CONFIG_ADS7843E_SPIDEV 1
 #endif
 
-#if CONFIG_ADS7843E_SPIDEV != 3
+#if CONFIG_ADS7843E_SPIDEV != 1
-#  error "CONFIG_ADS7843E_SPIDEV must be three"
+#  error "CONFIG_ADS7843E_SPIDEV must be one"
 #endif
 
 #ifndef CONFIG_ADS7843E_DEVMINOR
 #  define CONFIG_ADS7843E_DEVMINOR 0
 #endif
 
+/* REVISIT:  Currently, XPT2046 reports BUSY all of the time.  This is
+ * probably GPIO setting issues.  But there is this cryptic statement in
+ * the XPT2046 spec:  "No DCLK delay required with dedicated serial port."
+ *
+ * The busy state is used by the XPT2046 driver to control the delay
+ * between sending the command, then reading the returned data.
+ */
+
+#define XPT2046_NO_BUSY 1
+
 /****************************************************************************
  * Private Types
  ****************************************************************************/
@@ -100,12 +110,12 @@
  ****************************************************************************/
 
 /* IRQ/GPIO access callbacks.  These operations all hidden behind
- * callbacks to isolate the ADS7843E driver from differences in GPIO
+ * callbacks to isolate the XPT2046 driver from differences in GPIO
  * interrupt handling by varying boards and MCUs.  If possible,
  * interrupts should be configured on both rising and falling edges
  * so that contact and loss-of-contact events can be detected.
  *
- * attach  - Attach the ADS7843E interrupt handler to the GPIO interrupt
+ * attach  - Attach the XPT2046 interrupt handler to the GPIO interrupt
  * enable  - Enable or disable the GPIO interrupt
  * clear   - Acknowledge/clear any pending GPIO interrupt
  * pendown - Return the state of the pen down GPIO input
@@ -121,9 +131,9 @@ static bool tsc_pendown(FAR struct ads7843e_config_s *state);
  * Private Data
  ****************************************************************************/
 
-/* A reference to a structure of this type must be passed to the ADS7843E
+/* A reference to a structure of this type must be passed to the XPT2046
  * driver.  This structure provides information about the configuration
- * of the ADS7843E and provides some board-specific hooks.
+ * of the XPT2046 and provides some board-specific hooks.
  *
  * Memory for this structure is provided by the caller.  It is not copied
  * by the driver and is presumed to persist while the driver is active.
@@ -144,12 +154,12 @@ static struct ads7843e_config_s g_tscinfo =
  ****************************************************************************/
 
 /* IRQ/GPIO access callbacks.  These operations all hidden behind
- * callbacks to isolate the ADS7843E driver from differences in GPIO
+ * callbacks to isolate the XPT2046 driver from differences in GPIO
  * interrupt handling by varying boards and MCUs.  If possible,
  * interrupts should be configured on both rising and falling edges
  * so that contact and loss-of-contact events can be detected.
  *
- * attach  - Attach the ADS7843E interrupt handler to the GPIO interrupt
+ * attach  - Attach the XPT2046 interrupt handler to the GPIO interrupt
  * enable  - Enable or disable the GPIO interrupt
  * clear   - Acknowledge/clear any pending GPIO interrupt
  * pendown - Return the state of the pen down GPIO input
@@ -183,6 +193,20 @@ static void tsc_clear(FAR struct ads7843e_config_s *state)
 
 static bool tsc_busy(FAR struct ads7843e_config_s *state)
 {
+/* The busy state is used by the XPT2046 driver to control the delay
+ * between sending the command, then reading the returned data.
+ */
+
+#ifdef XPT2046_NO_BUSY
+/* REVISIT:  Currently, XPT2046 reports BUSY all of the time.  This is
+ * probably GPIO setting issues.  But there is this cryptic statement in
+ * the XPT2046 spec:  "No DCLK delay required with dedicated serial port."
+ */
+
+  return false;
+
+#else /* XPT2046_NO_BUSY */
+
 #if defined(CONFIG_DEBUG_INPUT) && defined(CONFIG_DEBUG_VERBOSE)
   static bool last = (bool)-1;
 #endif
@@ -199,6 +223,8 @@ static bool tsc_busy(FAR struct ads7843e_config_s *state)
 #endif
 
   return busy;
+
+#endif /* XPT2046_NO_BUSY */
 }
 
 static bool tsc_pendown(FAR struct ads7843e_config_s *state)
@@ -237,37 +263,50 @@ static bool tsc_pendown(FAR struct ads7843e_config_s *state)
 
 int arch_tcinitialize(int minor)
 {
+  static bool initialized = false;
   FAR struct spi_dev_s *dev;
   int ret;
 
-  idbg("minor %d\n", minor);
+  idbg("initialized:%d minor:%d\n", initialized, minor);
   DEBUGASSERT(minor == 0);
 
-  /* Configure and enable the ADS7843E PENIRQ pin as an interrupting input. */
+  /* Since there is no uninitialized logic, this initialization can be
+   * performed only one time.
+   */
 
-  (void)lpc17_configgpio(GPIO_TC_PENIRQ);
+  if (!initialized)
-
-  /* Configure the ADS7843E BUSY pin as a normal input. */
-
-  (void)lpc17_configgpio(GPIO_TC_BUSY);
-
-  /* Get an instance of the SPI interface */
-
-  dev = lpc17_sspinitialize(CONFIG_ADS7843E_SPIDEV);
-  if (!dev)
     {
-      idbg("Failed to initialize SPI bus %d\n", CONFIG_ADS7843E_SPIDEV);
+      /* Configure and enable the XPT2046 PENIRQ pin as an interrupting input. */
-      return -ENODEV;
-    }
 
-  /* Initialize and register the SPI touschscreen device */
+      (void)lpc17_configgpio(GPIO_TC_PENIRQ);
 
-  ret = ads7843e_register(dev, &g_tscinfo, CONFIG_ADS7843E_DEVMINOR);
+      /* Configure the XPT2046 BUSY pin as a normal input. */
-  if (ret < 0)
+
-    {
+#ifndef XPT2046_NO_BUSY
-      idbg("Failed to initialize SPI bus %d\n", CONFIG_ADS7843E_SPIDEV);
+      (void)lpc17_configgpio(GPIO_TC_BUSY);
-      /* up_spiuninitialize(dev); */
+#endif
-      return -ENODEV;
+
+      /* Get an instance of the SPI interface */
+
+      dev = lpc17_sspinitialize(CONFIG_ADS7843E_SPIDEV);
+      if (!dev)
+        {
+          idbg("Failed to initialize SPI bus %d\n", CONFIG_ADS7843E_SPIDEV);
+          return -ENODEV;
+        }
+
+      /* Initialize and register the SPI touchscreen device */
+
+      ret = ads7843e_register(dev, &g_tscinfo, CONFIG_ADS7843E_DEVMINOR);
+      if (ret < 0)
+        {
+          idbg("Failed to register touchscreen device minor=%d\n",
+               CONFIG_ADS7843E_DEVMINOR);
+          /* up_spiuninitialize(dev); */
+          return -ENODEV;
+        }
+
+      initialized = true;
     }
 
   return OK;
@@ -291,7 +330,7 @@ int arch_tcinitialize(int minor)
 
 void arch_tcuninitialize(void)
 {
-  /* No support for un-initializing the touchscreen ADS7843E device yet */
+  /* No support for un-initializing the touchscreen XPT2046 device yet */
 }
 
 #endif /* CONFIG_INPUT_ADS7843E */

drivers/input/Kconfig

@@ -57,13 +57,27 @@ config ADS7843E_NPOLLWAITERS
 	---help---
 		Maximum number of threads that can be waiting on poll()
 
+config ADS7843E_SPIDEV
+	int "SPI bus number"
+	default 0
+	---help---
+		Selects the SPI bus number identying that SPI interface that
+		connects the ADS843E to the MCU.
+
+config ADS7843E_DEVMINOR
+	int "Input device minor number"
+	default 0
+	---help---
+		The ADS7843E device will be registered as /dev/inputN where N is the
+		value provided by this setting.
+
 config ADS7843E_SPIMODE
 	int "SPI mode"
 	default 0
 	range 0,3
 	---help---
-		Controls the SPI mode.  The device should work in mode 0, but sometimes
+		Controls the SPI mode.  The device should work in mode 0, but
-		you need to experiment.
+		sometimes you need to experiment.
 
 config ADS7843E_FREQUENCY
 	int "SPI frequency"