From 947acd6c1a1eef21c97f147b58224fd85e8dc880 Mon Sep 17 00:00:00 2001
From: Gregory Nutt <gnutt@nuttx.org>
Date: Wed, 22 Mar 2017 15:53:12 -0600
Subject: [PATCH] Small changes from review of last PR

---
 arch/arm/src/stm32/Kconfig             | 10 +++---
 arch/arm/src/stm32/chip/stm32_flash.h  |  1 -
 arch/arm/src/stm32/stm32_flash.c       | 43 ++++++++++----------------
 configs/clicker2-stm32/src/stm32_spi.c |  2 +-
 4 files changed, 24 insertions(+), 32 deletions(-)

diff --git a/arch/arm/src/stm32/Kconfig b/arch/arm/src/stm32/Kconfig
index 72f8a17fbb..9e3ce56127 100644
--- a/arch/arm/src/stm32/Kconfig
+++ b/arch/arm/src/stm32/Kconfig
@@ -2634,10 +2634,12 @@ config STM32_FLASH_PREFETCH
 	properly and enabling this option may interfere with ADC accuracy.
 
 config STM32_FLASH_WORKAROUND_DATA_CACHE_CORRUPTION_ON_RWW
-    bool "Enable the workaround to fix flash data cache corruption when reading from one flash bank while writing on other flash bank"
-    default n
-    ---help---
-    See your STM32 errata to check if your STM32 is affected by this problem.
+	bool "Workaround for FLASH data cache corruption"
+	default n
+	---help---
+		Enable the workaround to fix flash data cache corruption when reading
+		from one flash bank while writing on other flash bank.  See your STM32
+		errata to check if your STM32 is affected by this problem.
 
 choice
 	prompt "JTAG Configuration"
diff --git a/arch/arm/src/stm32/chip/stm32_flash.h b/arch/arm/src/stm32/chip/stm32_flash.h
index 16c67a933e..32eeaf90dd 100644
--- a/arch/arm/src/stm32/chip/stm32_flash.h
+++ b/arch/arm/src/stm32/chip/stm32_flash.h
@@ -392,7 +392,6 @@
  * Public Functions
  ************************************************************************************/
 
-void stm32_flash_initialize(void);
 void stm32_flash_lock(void);
 void stm32_flash_unlock(void);
 
diff --git a/arch/arm/src/stm32/stm32_flash.c b/arch/arm/src/stm32/stm32_flash.c
index 4907aa9f0a..8ba48a8262 100644
--- a/arch/arm/src/stm32/stm32_flash.c
+++ b/arch/arm/src/stm32/stm32_flash.c
@@ -48,8 +48,10 @@
 #include <nuttx/config.h>
 #include <nuttx/arch.h>
 
-#include <errno.h>
 #include <stdbool.h>
+#include <semaphore.h>
+#include <assert.h>
+#include <errno.h>
 
 #include "stm32_flash.h"
 #include "stm32_rcc.h"
@@ -82,31 +84,27 @@
 #define FLASH_SR_WRITE_PROTECTION_ERROR  FLASH_SR_WRPERR
 #endif
 
+/************************************************************************************
+ * Private Data
+ ************************************************************************************/
+
+static sem_t g_sem = SEM_INITIALIZER(1);
+
 /************************************************************************************
  * Private Functions
  ************************************************************************************/
 
-static sem_t g_sem;
-/*
- * After all SMT32 boards starts calling stm32_flash_initialize() this can
- * be removed.
- */
-static bool g_initialized = false;
-
 static void sem_lock(void)
 {
-  if (g_initialized)
+  while (sem_wait(&g_sem) < 0)
     {
-      sem_wait(&g_sem);
+      DEBUGASSERT(errno == EINTR);
     }
 }
 
-static void sem_unlock(void)
+static inline void sem_unlock(void)
 {
-  if (g_initialized)
-    {
-      sem_post(&g_sem);
-    }
+  sem_post(&g_sem);
 }
 
 static void flash_unlock(void)
@@ -137,24 +135,18 @@ static void data_cache_disable(void)
 
 static void data_cache_enable(void)
 {
-  /* reset data cache */
+  /* Reset data cache */
+
   modifyreg32(STM32_FLASH_ACR, 0, FLASH_ACR_DCRST);
 
-  /* enable data cache */
+  /* Enable data cache */
+
   modifyreg32(STM32_FLASH_ACR, 0, FLASH_ACR_DCEN);
 }
 
 /************************************************************************************
  * Public Functions
  ************************************************************************************/
-void stm32_flash_initialize(void)
-{
-  g_initialized = true;
-  /*
-   * Initialize the semaphore that manages exclusive access flash registers
-   */
-  sem_init(&g_sem, 0, 1);
-}
 
 void stm32_flash_unlock(void)
 {
@@ -171,7 +163,6 @@ void stm32_flash_lock(void)
 }
 
 #if defined(CONFIG_STM32_STM32F10XX) || defined(CONFIG_STM32_STM32F30XX)
-
 size_t up_progmem_pagesize(size_t page)
 {
   return STM32_FLASH_PAGESIZE;
diff --git a/configs/clicker2-stm32/src/stm32_spi.c b/configs/clicker2-stm32/src/stm32_spi.c
index 7e231d108b..87e6e8d1d1 100644
--- a/configs/clicker2-stm32/src/stm32_spi.c
+++ b/configs/clicker2-stm32/src/stm32_spi.c
@@ -63,7 +63,7 @@
  * Name: stm32_spidev_initialize
  *
  * Description:
- *   Called to configure SPI chip select GPIO pins for the stm32f4discovery board.
+ *   Called to configure SPI chip select GPIO pins for the Mikroe Clicker2 STM32 board.
  *
  ************************************************************************************/