stm32h7/linum-stm32h753bi: Add buzzer support

Signed-off-by: Jorge Guzman <jorge.gzm@gmail.com>

Documentation/platforms/arm/stm32h7/boards/linum-stm32h753bi/index.rst

@@ -49,6 +49,8 @@ Expansion connector 2 features.
   - 6 PWM Channels
   - 10 ADCs
 
+Board documentation: https://wittetech.com/
+
 LEDs
 ====
 
@@ -301,9 +303,9 @@ LCD
 =======
 The LINUM-STM32H753BI use the LTDC to support one LCD with RGB connection.
 
-  =========== =====
+  ============= =====
   LTDC          PINS
-  =========== =====
+  ============= =====
   LTDC_B0       PF0
   LTDC_B1       PJ13
   LTDC_B2       PJ14
@@ -332,11 +334,6 @@ The LINUM-STM32H753BI use the LTDC to support one LCD with RGB connection.
   LTDC_R6       PJ5
   LTDC_R7       PJ6
   LTDC_VSYNC    PI9
-  =========== =====
-
-  ============= =====
-  PWM           PINS
-  ============= =====
   PWM_BACKLIGHT PH6
   ============= =====
 
@@ -352,15 +349,15 @@ The LINUM-STM32H753BI has one I2S output.
   I2S2_SDO PI3
   ======== =====
 
-BUZZER
+PWM
 =======
-The LINUM-STM32H753BI has a buzzer without internal oscillator
+The LINUM-STM32H753BI has a buzzer without internal oscillator connected to PB7
 
-  ======= =====
+  ========= =====
   GPIO      PINS
-  ======= =====
+  ========= =====
-  BUZZER  PC13  
+  BUZZER    PB7  
-  ======= =====
+  ========= =====
 
 ==============
 
@@ -451,10 +448,29 @@ The SD card can then be mounted by the NSH commands::
 eeprom
 ------
 
-Use dd command to write and read data from EEPROM as below:::
+Use **dd** command to write and read data from EEPROM as below:::
 
     nsh> dd if=/dev/console of=/dev/eeprom bs=1 count=35
     Witte-Tech Linum-STM32H753BI board
     nsh> dd if=/dev/eeprom of=/dev/console bs=4 count=35
     Witte-Tech Linum-STM32H753BI board
     nsh>
+
+buzzer
+------
+
+This example use the timer 4 with channel 2 to generate a PWM output signal on buzzer pin::
+
+    nsh> ls /dev
+    /dev:
+    console
+    null
+    pwm0
+    rtc0
+    ttyS0
+    nsh> pwm -d 75 -t 3
+    pwm_main: starting output with frequency: 100 duty: 0000bfff
+    pwm_main: stopping output
+    nsh> pwm -f 300 -t 3
+    pwm_main: starting output with frequency: 300 duty: 0000bfff
+    pwm_main: stopping output

arch/arm/src/stm32/stm32_pwm.c

@@ -247,7 +247,7 @@
 #  define TIMRST_TIM16     RCC_APB1RSTR_TIM16RST
 #  define TIMCLK_TIM17     STM32_APB1_TIM17_CLKIN
 #  define TIMRCCEN_TIM17   STM32_RCC_APB1ENR
-#  define TIMEN_TIM17      RCC_APB1ENR_TIM71EN
+#  define TIMEN_TIM17      RCC_APB1ENR_TIM17EN
 #  define TIMRCCRST_TIM17  STM32_RCC_APB1RSTR
 #  define TIMRST_TIM17     RCC_APB1RSTR_TIM17RST
 #endif

arch/arm/src/stm32h7/stm32_pwm.c

@@ -145,7 +145,7 @@
 #define TIMRST_TIM16     RCC_APB2RSTR_TIM16RST
 #define TIMCLK_TIM17     STM32_APB2_TIM17_CLKIN
 #define TIMRCCEN_TIM17   STM32_RCC_APB2ENR
-#define TIMEN_TIM17      RCC_APB2ENR_TIM71EN
+#define TIMEN_TIM17      RCC_APB2ENR_TIM17EN
 #define TIMRCCRST_TIM17  STM32_RCC_APB2RSTR
 #define TIMRST_TIM17     RCC_APB2RSTR_TIM17RST
 

boards/arm/stm32h7/linum-stm32h753bi/configs/buzzer/defconfig

@@ -0,0 +1,61 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_NSH_DISABLE_IFCONFIG is not set
+# CONFIG_NSH_DISABLE_PS is not set
+# CONFIG_STANDARD_SERIAL is not set
+# CONFIG_STM32H7_USE_LEGACY_PINMAP is not set
+CONFIG_ARCH="arm"
+CONFIG_ARCH_BOARD="linum-stm32h753bi"
+CONFIG_ARCH_BOARD_LINUM_STM32H753BI=y
+CONFIG_ARCH_CHIP="stm32h7"
+CONFIG_ARCH_CHIP_STM32H753BI=y
+CONFIG_ARCH_CHIP_STM32H7=y
+CONFIG_ARCH_CHIP_STM32H7_CORTEXM7=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_ARMV7M_DCACHE=y
+CONFIG_ARMV7M_DCACHE_WRITETHROUGH=y
+CONFIG_ARMV7M_DTCM=y
+CONFIG_ARMV7M_ICACHE=y
+CONFIG_BOARD_LOOPSPERMSEC=43103
+CONFIG_BUILTIN=y
+CONFIG_DEBUG_FEATURES=y
+CONFIG_DEBUG_SYMBOLS=y
+CONFIG_EXAMPLES_ALARM=y
+CONFIG_EXAMPLES_PWM=y
+CONFIG_INIT_ENTRYPOINT="nsh_main"
+CONFIG_INTELHEX_BINARY=y
+CONFIG_LIBM=y
+CONFIG_MM_REGIONS=4
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_LINELEN=64
+CONFIG_NSH_READLINE=y
+CONFIG_PREALLOC_TIMERS=4
+CONFIG_PWM=y
+CONFIG_RAM_SIZE=245760
+CONFIG_RAM_START=0x20010000
+CONFIG_RAW_BINARY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_RTC_ALARM=y
+CONFIG_RTC_DATETIME=y
+CONFIG_RTC_DRIVER=y
+CONFIG_SCHED_WAITPID=y
+CONFIG_START_DAY=6
+CONFIG_START_MONTH=12
+CONFIG_START_YEAR=2011
+CONFIG_STM32H7_PWR=y
+CONFIG_STM32H7_RTC=y
+CONFIG_STM32H7_TIM4=y
+CONFIG_STM32H7_TIM4_CH2OUT=y
+CONFIG_STM32H7_TIM4_CHANNEL=2
+CONFIG_STM32H7_TIM4_PWM=y
+CONFIG_STM32H7_USART1=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_TASK_NAME_SIZE=0
+CONFIG_USART1_SERIAL_CONSOLE=y

boards/arm/stm32h7/linum-stm32h753bi/include/board.h

@@ -396,6 +396,11 @@
 #define GPIO_I2C3_SCL (GPIO_I2C3_SCL_2 | GPIO_SPEED_100MHz) /* PH7 */
 #define GPIO_I2C3_SDA (GPIO_I2C3_SDA_2 | GPIO_SPEED_100MHz) /* PH8 */
 
+/* PWM - Buzzer */
+
+#define GPIO_TIM17_CH1OUT  (GPIO_TIM17_CH1NOUT_1) /* PB7 */
+#define GPIO_TIM4_CH2OUT   (GPIO_TIM4_CH2OUT_1)   /* PB7 */
+
 /****************************************************************************
  * Public Data
  ****************************************************************************/

boards/arm/stm32h7/linum-stm32h753bi/src/CMakeLists.txt

@@ -48,6 +48,10 @@ if(CONFIG_I2C_EE_24XX)
   list(APPEND SRCS stm32_at24.c)
 endif()
 
+if(CONFIG_PWM)
+  list(APPEND SRCS stm32_pwm.c)
+endif()
+
 target_sources(board PRIVATE ${SRCS})
 
 set_property(GLOBAL PROPERTY LD_SCRIPT "${NUTTX_BOARD_DIR}/scripts/flash.ld")

boards/arm/stm32h7/linum-stm32h753bi/src/Makefile

@@ -46,6 +46,10 @@ ifeq ($(CONFIG_I2C_EE_24XX),y)
 CSRCS += stm32_at24.c
 endif
 
+ifeq ($(CONFIG_PWM),y)
+CSRCS += stm32_pwm.c
+endif
+
 ifeq ($(CONFIG_BOARDCTL),y)
 CSRCS += stm32_appinitialize.c
 endif

boards/arm/stm32h7/linum-stm32h753bi/src/linum-stm32h753bi.h

@@ -99,6 +99,10 @@
 #define SDIO_SLOTNO        0
 #define SDIO_MINOR         0
 
+/* PWM */
+
+#define BUZZER_PWMTIMER 4
+
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/
@@ -172,4 +176,16 @@ int stm32_sdio_initialize(void);
 int stm32_at24_init(char *path);
 #endif
 
+/****************************************************************************
+ * Name: stm32_pwm_setup
+ *
+ * Description:
+ *   Initialize PWM and register the PWM device.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_PWM
+int stm32_pwm_setup(void);
+#endif
+
 #endif /* __BOARDS_ARM_STM32H7_LINUM_STM32H753BI_SRC_LINUM_STM32H753BI_H */

boards/arm/stm32h7/linum-stm32h753bi/src/stm32_bringup.c

@@ -208,5 +208,15 @@ int stm32_bringup(void)
     }
 #endif
 
+#ifdef CONFIG_PWM
+  /* Initialize PWM and register the PWM device. */
+
+  ret = stm32_pwm_setup();
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: stm32_pwm_setup() failed: %d\n", ret);
+    }
+#endif
+
   return OK;
 }

boards/arm/stm32h7/linum-stm32h753bi/src/stm32_pwm.c

@@ -0,0 +1,108 @@
+/****************************************************************************
+ * boards/arm/stm32h7/linum-stm32h753bi/src/stm32_pwm.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/timers/pwm.h>
+#include <arch/board/board.h>
+
+#include "chip.h"
+#include "arm_internal.h"
+#include "stm32_pwm.h"
+#include "linum-stm32h753bi.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* Configuration ************************************************************/
+
+#define HAVE_PWM 1
+
+#ifndef CONFIG_PWM
+#  undef HAVE_PWM
+#endif
+
+#ifndef CONFIG_STM32H7_TIM4
+#  undef HAVE_PWM
+#endif
+
+#ifndef CONFIG_STM32H7_TIM4_PWM
+#  undef HAVE_PWM
+#endif
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: stm32_pwm_setup
+ *
+ * Description:
+ *   Initialize PWM and register the PWM device.
+ *
+ ****************************************************************************/
+
+int stm32_pwm_setup(void)
+{
+#ifdef HAVE_PWM
+  static bool initialized = false;
+  struct pwm_lowerhalf_s *pwm;
+  int ret;
+
+  /* Have we already initialized? */
+
+  if (!initialized)
+    {
+      /* Get an instance of the PWM interface */
+
+      pwm = stm32_pwminitialize(BUZZER_PWMTIMER);
+      if (!pwm)
+        {
+          tmrerr("ERROR: Failed to get the STM32 PWM lower half\n");
+          return -ENODEV;
+        }
+
+      /* Register the PWM driver at "/dev/pwm0" */
+
+      ret = pwm_register("/dev/pwm0", pwm);
+      if (ret < 0)
+        {
+          tmrerr("ERROR: pwm_register failed: %d\n", ret);
+          return ret;
+        }
+
+      /* Now we are initialized */
+
+      initialized = true;
+    }
+
+  return OK;
+#else
+  return -ENODEV;
+#endif
+}