STM32F4-Discvovery: Add low level support for the Zero Cross driver. From Alan Carvalho de Assis

configs/stm32f4discovery/src/Makefile

@@ -92,6 +92,10 @@ ifeq ($(CONFIG_PM_BUTTONS),y)
 CSRCS += stm32_pmbuttons.c
 endif
 
+ifeq ($(CONFIG_ZEROCROSS),y)
+CSRCS += stm32_zerocross.c
+endif
+
 ifeq ($(CONFIG_ARCH_IDLE_CUSTOM),y)
 CSRCS += stm32_idle.c
 endif

configs/stm32f4discovery/src/stm32_bringup.c

@@ -97,6 +97,10 @@ int stm32_bringup(void)
 #endif
   int ret = OK;
 
+#ifdef CONFIG_ZEROCROSS
+  stm32_zerocross_initialize();
+#endif
+
 #ifdef HAVE_SDIO
   /* Initialize the SDIO block driver */
 

configs/stm32f4discovery/src/stm32_zerocross.c

@@ -0,0 +1,204 @@
+/****************************************************************************
+ * configs/stm32f4discovery/src/stm32_zerocross.c
+ *
+ *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * 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 <stdint.h>
+#include <debug.h>
+
+#include <nuttx/arch.h>
+#include <nuttx/sensors/zerocross.h>
+
+#include "stm32_gpio.h"
+#include "stm32f4discovery.h"
+
+#ifdef CONFIG_ZEROCROSS
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static void zcross_enable(FAR const struct zc_lowerhalf_s *lower,
+                         zc_interrupt_t handler, FAR void *arg);
+
+static void zcross_disable(void);
+static int zcross_interrupt(int irq, FAR void *context);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/* Current interrupt handler and argument */
+
+static zc_interrupt_t g_zcrosshandler;
+static FAR void *g_zcrossarg;
+
+/* This is the zero cross lower half driver interface */
+
+static const struct zc_lowerhalf_s g_zcrosslower =
+{
+  .zc_enable     = zcross_enable,
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: zcross_enable
+ *
+ * Description:
+ *   Enable interrupts on the selected zero cross pin.  And empty
+ *   set will disable all interrupts.
+ *
+ ****************************************************************************/
+
+static void zcross_enable(FAR const struct zc_lowerhalf_s *lower,
+                          zc_interrupt_t handler, FAR void *arg)
+{
+  irqstate_t flags;
+  bool rising = false;
+  bool falling = true;
+  int i;
+
+  /* Start with all interrupts disabled */
+
+  flags = irqsave();
+  zcross_disable();
+
+  snllvdbg("handler: %p arg: %p\n", handler, arg);
+
+  if (handler)
+    {
+      g_zcrosshandler = handler;
+      g_zcrossarg     = arg;
+    }
+
+  (void)stm32_gpiosetevent(GPIO_ZEROCROSS, rising, falling,
+                           true, zcross_interrupt);
+
+  irqrestore(flags);
+}
+
+/****************************************************************************
+ * Name: zcross_disable
+ *
+ * Description:
+ *   Disable all joystick interrupts
+ *
+ ****************************************************************************/
+
+static void zcross_disable(void)
+{
+  irqstate_t flags;
+  int i;
+
+  /* Disable zero cross pin interrupt */
+
+  flags = irqsave();
+
+  (void)stm32_gpiosetevent(GPIO_ZEROCROSS, false, false, false, NULL);
+
+  irqrestore(flags);
+
+  /* Nullify the handler and argument */
+
+  g_zcrosshandler = NULL;
+  g_zcrossarg     = NULL;
+}
+
+/****************************************************************************
+ * Name: zcross_interrupt
+ *
+ * Description:
+ *   Zero Cross interrupt handler
+ *
+ ****************************************************************************/
+
+static int zcross_interrupt(int irq, FAR void *context)
+{
+  DEBUGASSERT(g_zcrosshandler);
+  if (g_zcrosshandler)
+    {
+      g_zcrosshandler(&g_zcrosslower, g_zcrossarg);
+    }
+
+  return OK;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: stm32_zerocross_initialize
+ *
+ * Description:
+ *   Initialize and register the zero cross driver
+ *
+ ****************************************************************************/
+
+int stm32_zerocross_initialize(void)
+{
+  int i;
+
+  /* Configure the GPIO pin as input.    NOTE: This is unnecessary for
+   * interrupting pins since it will also be done by stm32_gpiosetevent().
+   */
+
+  stm32_configgpio(GPIO_ZEROCROSS);
+
+  /* Make sure that all interrupts are disabled */
+
+  zcross_disable();
+
+  /* Register the zero cross device as /dev/zc0 */
+
+  return zc_register("/dev/zc0", &g_zcrosslower);
+}
+
+#endif /* CONFIG_ZEROCROSS */

configs/stm32f4discovery/src/stm32f4discovery.h

@@ -191,6 +191,10 @@
 
 #define GPIO_BTN_USER   (GPIO_INPUT|GPIO_FLOAT|GPIO_EXTI|GPIO_PORTA|GPIO_PIN0)
 
+/* ZERO CROSS pin definiton */
+
+#define GPIO_ZEROCROSS  (GPIO_INPUT|GPIO_FLOAT|GPIO_EXTI|GPIO_PORTD|GPIO_PIN0)
+
 /* PWM
  *
  * The STM32F4 Discovery has no real on-board PWM devices, but the board can be
@@ -515,5 +519,17 @@ int stm32_sdio_initialize(void);
 void weak_function stm32_netinitialize(void);
 #endif
 
+/****************************************************************************
+ * Name: stm32_zerocross_initialize
+ *
+ * Description:
+ *   Initialize and register the zero cross driver
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_ZEROCROSS
+int stm32_zerocross_initialize(void);
+#endif
+
 #endif /* __ASSEMBLY__ */
 #endif /* __CONFIGS_STM32F4DISCOVERY_SRC_STM32F4DISCOVERY_H */