From c7685742be49bd4e6f9dc97723238c63dadaad88 Mon Sep 17 00:00:00 2001
From: David Saada <david.saada@arm.com>
Date: Tue, 14 Aug 2018 19:51:03 +0300
Subject: [PATCH] Add some logic related to initialization

- Add an initialization flag on which read/program/erase actions depend.
- Add an init reference count.
---
 DataFlashBlockDevice.cpp | 45 +++++++++++++++++++++++++++++++++++++++-
 DataFlashBlockDevice.h   |  2 ++
 2 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/DataFlashBlockDevice.cpp b/DataFlashBlockDevice.cpp
index 0d2309661a..3661b78d32 100644
--- a/DataFlashBlockDevice.cpp
+++ b/DataFlashBlockDevice.cpp
@@ -15,6 +15,7 @@
  */
 
 #include "DataFlashBlockDevice.h"
+#include "mbed_critical.h"
 
 #include <inttypes.h>
 
@@ -138,7 +139,11 @@ DataFlashBlockDevice::DataFlashBlockDevice(PinName mosi,
     :   _spi(mosi, miso, sclk),
         _cs(cs, 1),
         _nwp(nwp),
-        _device_size(0)
+        _device_size(0),
+        _page_size(0),
+        _block_size(0),
+        _is_initialized(0),
+        _init_ref_count(0)
 {
     /* check that frequency is within range */
     if (freq > DATAFLASH_LOW_FREQUENCY) {
@@ -161,6 +166,16 @@ int DataFlashBlockDevice::init()
 {
     DEBUG_PRINTF("init\r\n");
 
+    if (!_is_initialized) {
+        _init_ref_count = 0;
+    }
+
+    uint32_t val = core_util_atomic_incr_u32(&_init_ref_count, 1);
+
+    if (val != 1) {
+        return BD_ERROR_OK;
+    }
+
     int result = BD_ERROR_DEVICE_ERROR;
 
     /* read ID register to validate model and set dimensions */
@@ -262,6 +277,10 @@ int DataFlashBlockDevice::init()
     /* write protect device when idle */
     _write_enable(false);
 
+    if (result == BD_ERROR_OK) {
+        _is_initialized = true;
+    }
+
     return result;
 }
 
@@ -269,6 +288,18 @@ int DataFlashBlockDevice::deinit()
 {
     DEBUG_PRINTF("deinit\r\n");
 
+    if (!_is_initialized) {
+        _init_ref_count = 0;
+        return BD_ERROR_OK;
+    }
+
+    uint32_t val = core_util_atomic_decr_u32(&_init_ref_count, 1);
+
+    if (val) {
+        return BD_ERROR_OK;
+    }
+
+    _is_initialized = false;
     return BD_ERROR_OK;
 }
 
@@ -276,6 +307,10 @@ int DataFlashBlockDevice::read(void *buffer, bd_addr_t addr, bd_size_t size)
 {
     DEBUG_PRINTF("read: %p %" PRIX64 " %" PRIX64 "\r\n", buffer, addr, size);
 
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
     int result = BD_ERROR_DEVICE_ERROR;
 
     /* check parameters are valid and the read is within bounds */
@@ -317,6 +352,10 @@ int DataFlashBlockDevice::program(const void *buffer, bd_addr_t addr, bd_size_t
 {
     DEBUG_PRINTF("program: %p %" PRIX64 " %" PRIX64 "\r\n", buffer, addr, size);
 
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
     int result = BD_ERROR_DEVICE_ERROR;
 
     /* check parameters are valid and the write is within bounds */
@@ -379,6 +418,10 @@ int DataFlashBlockDevice::erase(bd_addr_t addr, bd_size_t size)
 {
     DEBUG_PRINTF("erase: %" PRIX64 " %" PRIX64 "\r\n", addr, size);
 
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
     int result = BD_ERROR_DEVICE_ERROR;
 
     /* check parameters are valid and the erase is within bounds */
diff --git a/DataFlashBlockDevice.h b/DataFlashBlockDevice.h
index e73b40222f..d3e0448383 100644
--- a/DataFlashBlockDevice.h
+++ b/DataFlashBlockDevice.h
@@ -163,6 +163,8 @@ private:
     uint32_t _device_size;
     uint16_t _page_size;
     uint16_t _block_size;
+    bool _is_initialized;
+    uint32_t _init_ref_count;
 
     // Internal functions
     uint16_t _get_register(uint8_t opcode);