Squashed commit of the following:

configs/stm32f4discovery/src: Add board support to MAX7219 as numeric display controller

    drivers/leds/max7219.c: Add support to MAX7219 to control 7-segment displays

configs/stm32f4discovery/src/Makefile

@@ -105,6 +105,10 @@ ifeq ($(CONFIG_STM32_ETHMAC),y)
 CSRCS += stm32_ethernet.c
 endif
 
+ifeq ($(CONFIG_LEDS_MAX7219),y)
+  CSRCS += stm32_max7219_leds.c
+endif
+
 ifeq ($(CONFIG_RGBLED),y)
 CSRCS += stm32_rgbled.c
 endif

configs/stm32f4discovery/src/stm32_bringup.c

@@ -125,6 +125,14 @@ int stm32_bringup(void)
   stm32_zerocross_initialize();
 #endif
 
+#ifdef CONFIG_LEDS_MAX7219
+  ret = stm32_max7219init("/dev/numdisp0");
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: max7219_leds_register failed: %d\n", ret);
+    }
+#endif
+
 #ifdef CONFIG_RGBLED
   /* Configure the RGB LED driver */
 

configs/stm32f4discovery/src/stm32_max7219_leds.c

@@ -0,0 +1,103 @@
+/****************************************************************************
+ * configs/stm32f4discovery/src/stm32_max7219_leds.c
+ *
+ *   Copyright (C) 2018 Alan Carvalho de Assis. All rights reserved.
+ *   Author: Alan Carvalho de Assis <acassis@gmail.com>
+ *
+ * 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 <errno.h>
+#include <debug.h>
+
+#include <nuttx/spi/spi.h>
+#include <nuttx/leds/max7219.h>
+
+#include "stm32.h"
+#include "stm32_spi.h"
+#include "stm32f4discovery.h"
+
+#if defined(CONFIG_SPI) && defined(CONFIG_STM32_SPI1) && \
+    defined(CONFIG_LEDS_MAX7219)
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#define MAX7219_SPI_PORTNO 1   /* On SPI1 */
+
+/************************************************************************************
+ * Public Functions
+ ************************************************************************************/
+
+/************************************************************************************
+ * Name: stm32_max7219init
+ *
+ * Description:
+ *   Initialize the max7219 to control 7-segment numeric display
+ *
+ * Input Parameters:
+ *   devpath - The full path to the driver to register. E.g., "/dev/numdisp0"
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ************************************************************************************/
+
+int stm32_max7219init(FAR const char *devpath)
+{
+  FAR struct spi_dev_s *spi;
+  int ret;
+
+  spi = stm32_spibus_initialize(MAX7219_SPI_PORTNO);
+  if (spi == NULL)
+    {
+      return -ENODEV;
+    }
+
+  /* Register the MAX7219 Driver at the specified location. */
+
+  ret = max7219_leds_register(devpath, spi);
+  if (ret < 0)
+    {
+      lederr("ERROR: max7219_leds_register(%s) failed: %d\n",
+             devpath, ret);
+      return ret;
+    }
+
+  return OK;
+}
+
+#endif /* CONFIG_SPI && CONFIG_LEDS_MAX7219 */

configs/stm32f4discovery/src/stm32_spi.c

@@ -75,7 +75,7 @@ void weak_function stm32_spidev_initialize(void)
 #if defined(CONFIG_STM32_SPI2) && defined(CONFIG_SENSORS_MAX31855)
   (void)stm32_configgpio(GPIO_MAX31855_CS); /* MAX31855 chip select */
 #endif
-#ifdef CONFIG_LCD_MAX7219
+#if defined(CONFIG_LCD_MAX7219) || defined(CONFIG_LEDS_MAX7219)
   (void)stm32_configgpio(GPIO_MAX7219_CS);  /* MAX7219 chip select */
 #endif
 #if defined(CONFIG_LCD_ST7567)
@@ -132,7 +132,7 @@ void stm32_spi1select(FAR struct spi_dev_s *dev, uint32_t devid, bool selected)
       stm32_gpiowrite(STM32_LCD_CS, !selected);
     }
 #endif
-#ifdef CONFIG_LCD_MAX7219
+#if defined(CONFIG_LCD_MAX7219) || defined(CONFIG_LEDS_MAX7219)
   if (devid == SPIDEV_DISPLAY(0))
     {
       stm32_gpiowrite(GPIO_MAX7219_CS, !selected);

configs/stm32f4discovery/src/stm32f4discovery.h

@@ -506,6 +506,18 @@ int stm32_lis3dshinitialize(FAR const char *devpath);
 int nunchuck_initialize(FAR char *devname);
 #endif
 
+/****************************************************************************
+ * Name: stm32_max7219init
+ *
+ * Description:
+ *   Initialize and register the max7219 numeric display controller
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_LEDS_MAX7219
+int stm32_max7219init(FAR const char *devpath);
+#endif
+
 /****************************************************************************
  * Name: stm32_usbinitialize
  *

drivers/leds/Kconfig

@@ -48,6 +48,13 @@ config LEDS_APA102
 	---help---
 		Enable support for the APA102 LED Strip driver.
 
+config LEDS_MAX7219
+	bool "MAX7219 Numeric Display"
+	default n
+	select SPI
+	---help---
+		Enable support for the MAX7219 to control 7-segment displays.
+
 config RGBLED
         bool "RGB LED Driver Support"
         default n

drivers/leds/Make.defs

@@ -56,6 +56,12 @@ ifeq ($(CONFIG_LEDS_APA102),y)
   LEDVPATH = :leds
 endif
 
+ifeq ($(CONFIG_LEDS_MAX7219),y)
+  CSRCS += max7219.c
+  LEDDEPATH = --dep-path leds
+  LEDVPATH = :leds
+endif
+
 ifeq ($(CONFIG_RGBLED),y)
   CSRCS += rgbled.c
   LEDDEPATH = --dep-path leds

drivers/leds/max7219.c

@@ -0,0 +1,323 @@
+/****************************************************************************
+ * drivers/sensors/max7219.c
+ * Maxim MAX7219 driver used to control 7-segment display.
+ *
+ *   Copyright (C) 2018 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2018 Alan Carvalho de Assis
+ *   Author: Alan Carvalho de Assis <acassis@gmail.com>
+ *
+ * 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 <stdlib.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/kmalloc.h>
+#include <nuttx/fs/fs.h>
+#include <nuttx/spi/spi.h>
+#include <nuttx/leds/max7219.h>
+
+#if defined(CONFIG_SPI) && defined(CONFIG_LEDS_MAX7219)
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* SPI frequency */
+
+#ifndef CONFIG_MAX7219_FREQUENCY
+#  define CONFIG_MAX7219_FREQUENCY 5000000
+#endif
+
+#ifndef CONFIG_MAX7219_INTENSITY
+#  define CONFIG_MAX7219_INTENSITY 8
+#endif
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+struct max7219_dev_s
+{
+  FAR struct spi_dev_s *spi; /* SPI interface */
+};
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static inline void max7219_configspi(FAR struct spi_dev_s *spi);
+static inline void max7219_write16(FAR struct max7219_dev_s *priv,
+                                   uint16_t value);
+
+/* Character driver methods */
+
+static int     max7219_open(FAR struct file *filep);
+static int     max7219_close(FAR struct file *filep);
+static ssize_t max7219_read(FAR struct file *filep, FAR char *buffer,
+                            size_t buflen);
+static ssize_t max7219_write(FAR struct file *filep, FAR const char *buffer,
+                            size_t buflen);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static const struct file_operations g_max7219fops =
+{
+  max7219_open,   /* open */
+  max7219_close,  /* close */
+  max7219_read,   /* read */
+  max7219_write,  /* write */
+  0,              /* seek */
+  0,              /* ioctl */
+#ifndef CONFIG_DISABLE_POLL
+  0,              /* poll */
+#endif
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+  NULL            /* unlink */
+#endif
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: max7219_configspi
+ *
+ * Description:
+ *   Set the SPI bus configuration
+ *
+ ****************************************************************************/
+
+static inline void max7219_configspi(FAR struct spi_dev_s *spi)
+{
+  /* Configure SPI for the MAX7219 */
+
+  SPI_SETMODE(spi, SPIDEV_MODE0);
+  SPI_SETBITS(spi, 8);
+  (void)SPI_HWFEATURES(spi, 0);
+  (void)SPI_SETFREQUENCY(spi, CONFIG_MAX7219_FREQUENCY);
+}
+
+/****************************************************************************
+ * Name: max7219_write16
+ *
+ * Description:
+ *   Write 16-bit to MAX7219
+ *
+ ****************************************************************************/
+
+static inline void max7219_write16(FAR struct max7219_dev_s *priv,
+                                   uint16_t value)
+{
+  /* If SPI bus is shared then lock and configure it */
+
+  (void)SPI_LOCK(priv->spi, true);
+
+  /* Configure the SPI */
+
+  max7219_configspi(priv->spi);
+
+  /* Select */
+
+  SPI_SELECT(priv->spi, SPIDEV_DISPLAY(0), true);
+
+  /* Send 16 bits (2 bytes) */
+
+  (void)SPI_SNDBLOCK(priv->spi, &value, 2);
+
+  /* Deselect */
+
+  SPI_SELECT(priv->spi, SPIDEV_DISPLAY(0), false);
+
+  /* Unlock bus */
+
+  (void)SPI_LOCK(priv->spi, false);
+}
+
+/****************************************************************************
+ * Name: max7219_open
+ *
+ * Description:
+ *   This function is called whenever the MAX7219 device is opened.
+ *
+ ****************************************************************************/
+
+static int max7219_open(FAR struct file *filep)
+{
+  return OK;
+}
+
+/****************************************************************************
+ * Name: max7219_close
+ *
+ * Description:
+ *   This routine is called when the LM-75 device is closed.
+ *
+ ****************************************************************************/
+
+static int max7219_close(FAR struct file *filep)
+{
+  return OK;
+}
+
+/****************************************************************************
+ * Name: max7219_read
+ ****************************************************************************/
+
+static ssize_t max7219_read(FAR struct file *filep, FAR char *buffer, size_t buflen)
+{
+  return -ENOSYS;
+}
+
+/****************************************************************************
+ * Name: max7219_write
+ ****************************************************************************/
+
+static ssize_t max7219_write(FAR struct file *filep, FAR const char *buffer,
+                          size_t buflen)
+{
+  FAR struct inode *inode = filep->f_inode;
+  FAR struct max7219_dev_s *priv = inode->i_private;
+  FAR const char *leds = (FAR char *) buffer;
+  uint16_t data;
+  uint8_t i;
+
+  if (!leds)
+    {
+      snerr("ERROR: Buffer is null\n");
+      return -1;
+    }
+
+  /* At least one display, so 1 byte */
+
+  if (buflen < 1)
+    {
+      snerr("ERROR: You need to control at least 1 digit!\n");
+      return -1;
+    }
+
+  /* It can control up to 8 digits (8 7-segment displays) */
+
+  if (buflen > 8)
+    {
+      snerr("ERROR: The limit is 8 digits!\n");
+      return -1;
+    }
+
+  /* Write each digit */
+
+  for (i = 0; i < buflen; i++)
+    {
+      data = (MAX7219_DIGIT0 + i) | (leds[i] - '0') << 8;
+      max7219_write16(priv, data);
+    }
+
+  /* All bytes were written */
+
+  return buflen;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: max7219_register
+ *
+ * Description:
+ *   Register the MAX7219 character device as 'devpath'
+ *
+ * Input Parameters:
+ *   devpath - The full path to the driver to register. E.g., "/dev/temp0"
+ *   i2c     - An instance of the I2C interface to use to communicate with
+ *             MAX7219
+ *   addr    - The I2C address of the LM-75.  The base I2C address of the
+ *             MAX7219 is 0x48.  Bits 0-3 can be controlled to get 8 unique
+ *             addresses from 0x48 through 0x4f.
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int max7219_leds_register(FAR const char *devpath, FAR struct spi_dev_s *spi)
+{
+  FAR struct max7219_dev_s *priv;
+  uint16_t data;
+  int ret;
+
+  /* Initialize the MAX7219 device structure */
+
+  priv = (FAR struct max7219_dev_s *)kmm_malloc(sizeof(struct max7219_dev_s));
+  if (!priv)
+    {
+      snerr("ERROR: Failed to allocate instance\n");
+      return -ENOMEM;
+    }
+
+  priv->spi = spi;
+
+  /* Leave the shutdown mode */
+
+  data = (MAX7219_SHUTDOWN) | (MAX7219_POWER_ON << 8);
+  max7219_write16(priv, data);
+
+  /* Setup defined intensity */
+
+  data = (MAX7219_INTENSITY) |
+         (DISPLAY_INTENSITY(CONFIG_MAX7219_INTENSITY) << 8);
+  max7219_write16(priv, data);
+
+  /* Enable decoding for all digits */
+
+  data = (MAX7219_DECODE_MODE) | (ENABLE_DECODE << 8);
+  max7219_write16(priv, data);
+
+  /* Register the character driver */
+
+  ret = register_driver(devpath, &g_max7219fops, 0666, priv);
+  if (ret < 0)
+    {
+      snerr("ERROR: Failed to register driver: %d\n", ret);
+      kmm_free(priv);
+    }
+
+  return ret;
+}
+#endif /* CONFIG_SPI && CONFIG_MAX7219 */

include/nuttx/leds/max7219.h

@@ -0,0 +1,123 @@
+/****************************************************************************
+ * include/nuttx/leds/max7219.h
+ *
+ *   Copyright (C) 2018 Alan Carvalho de Assis. All rights reserved.
+ *   Author: Alan Carvalho de Assis <acassis@gmail.com>
+ *
+ * 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 __INCLUDE_NUTTX_LEDS_MAX7219_H
+#define __INCLUDE_NUTTX_LEDS_MAX7219_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/fs/ioctl.h>
+
+/* Configuration
+ * CONFIG_SPI - Enables support for SPI drivers
+ * CONFIG_LEDS_MAX7219 - Enables support for the MAX7219 driver
+ */
+
+#if defined(CONFIG_SPI) && defined(CONFIG_LEDS_MAX7219)
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* MAX7219 register addresses */
+
+#define MAX7219_NOOP          (0x00)   /* No Operation          */
+#define MAX7219_DIGIT0        (0x01)   /* Digit 0 register      */
+#define MAX7219_DIGIT1        (0x02)   /* Digit 1 register      */
+#define MAX7219_DIGIT2        (0x03)   /* Digit 2 register      */
+#define MAX7219_DIGIT3        (0x04)   /* Digit 3 register      */
+#define MAX7219_DIGIT4        (0x05)   /* Digit 4 register      */
+#define MAX7219_DIGIT5        (0x06)   /* Digit 5 register      */
+#define MAX7219_DIGIT6        (0x07)   /* Digit 6 register      */
+#define MAX7219_DIGIT7        (0x08)   /* Digit 7 register      */
+#define MAX7219_DECODE_MODE   (0x09)   /* Decode Moder register */
+#define MAX7219_INTENSITY     (0x0a)   /* Intensity register    */
+#define MAX7219_SCAN_LIMIT    (0x0b)   /* Scan Limit register   */
+#define MAX7219_SHUTDOWN      (0x0c)   /* Shutdown register     */
+#define MAX7219_DISPLAY_TEST  (0x0f)   /* Display Test register */
+
+/* Default register values */
+
+#define ENABLE_DECODE         (0xff)    /* Enable decoding of all 7-seg */
+#define DISABLE_DECODE        (0x00)    /* Disable 7-seg decode         */
+#define DEFAULT_SCAN_LIMIT    (0x07)    /* Display all digits           */
+#define DISPLAY_INTENSITY(n)  (n & 0xf) /* low nimble defines it        */
+
+/* Only two power settings are supported: */
+
+#define MAX7219_POWER_OFF     0
+#define MAX7219_POWER_ON      1
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Name: max7219_leds_register
+ *
+ * Description:
+ *   Initialize the MAX7219 device as a LEDS interface.
+ *
+ * Input Parameters:
+ *   spi   - An instance of the SPI interface to use to communicate
+ *           with the MAX7219.
+ *   devno - Device number to identify current display.
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+ struct spi_dev_s;  /* Forward reference */
+int max7219_leds_register(FAR const char *devpath, FAR struct spi_dev_s *spi);
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* CONFIG_SPI && CONFIG_MAX7219 */
+#endif /* __INCLUDE_NUTTX_LEDS_MAX7219_H */