From d04c8e31412d3505d54a860958d9da52f07c312e Mon Sep 17 00:00:00 2001
From: David Saada <david.saada@arm.com>
Date: Thu, 2 Aug 2018 19:07:16 +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.
---
 SPIFBlockDevice.cpp | 43 +++++++++++++++++++++++++++++++++++++++++--
 SPIFBlockDevice.h   |  3 +++
 2 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/SPIFBlockDevice.cpp b/SPIFBlockDevice.cpp
index e2a0a9e11d..329e0a5806 100644
--- a/SPIFBlockDevice.cpp
+++ b/SPIFBlockDevice.cpp
@@ -15,7 +15,7 @@
  */
 
 #include "SPIFBlockDevice.h"
-
+#include "mbed_critical.h"
 
 // Read/write/erase sizes
 #define SPIF_READ_SIZE  1
@@ -49,7 +49,7 @@ enum ops {
  
 SPIFBlockDevice::SPIFBlockDevice(
     PinName mosi, PinName miso, PinName sclk, PinName cs, int freq)
-    : _spi(mosi, miso, sclk), _cs(cs), _size(0)
+    : _spi(mosi, miso, sclk), _cs(cs), _size(0), _is_initialized(false), _init_ref_count(0)
 {
     _cs = 1;
     _spi.frequency(freq);
@@ -57,6 +57,16 @@ SPIFBlockDevice::SPIFBlockDevice(
 
 int SPIFBlockDevice::init()
 {
+    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;
+    }
+
     // Check for vendor specific hacks, these should move into more general
     // handling when possible. RDID is not used to verify a device is attached.
     uint8_t id[3];
@@ -125,15 +135,28 @@ int SPIFBlockDevice::init()
         (table[4] << 0 ));
     _size = (density/8) + 1;
 
+    _is_initialized = true;
     return 0;
 }
 
 int SPIFBlockDevice::deinit()
 {
+    if (!_is_initialized) {
+        _init_ref_count = 0;
+        return 0;
+    }
+
+    uint32_t val = core_util_atomic_decr_u32(&_init_ref_count, 1);
+
+    if (val) {
+        return 0;
+    }
+
     // Latch write disable just to keep noise
     // from changing the device
     _cmdwrite(SPIF_WRDI, 0, 0, 0x0, NULL);
 
+    _is_initialized = false;
     return 0;
 }
 
@@ -249,6 +272,10 @@ int SPIFBlockDevice::_wren()
 
 int SPIFBlockDevice::read(void *buffer, bd_addr_t addr, bd_size_t size)
 {
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
     // Check the address and size fit onto the chip.
     MBED_ASSERT(is_valid_read(addr, size));
 
@@ -261,6 +288,10 @@ int SPIFBlockDevice::program(const void *buffer, bd_addr_t addr, bd_size_t size)
     // Check the address and size fit onto the chip.
     MBED_ASSERT(is_valid_program(addr, size));
 
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
     while (size > 0) {
         int err = _wren();
         if (err) {
@@ -292,6 +323,10 @@ int SPIFBlockDevice::erase(bd_addr_t addr, bd_size_t size)
     // Check the address and size fit onto the chip.
     MBED_ASSERT(is_valid_erase(addr, size));
 
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
     while (size > 0) {
         int err = _wren();
         if (err) {
@@ -336,6 +371,10 @@ bd_size_t SPIFBlockDevice::get_erase_size(bd_addr_t addr) const
 
 bd_size_t SPIFBlockDevice::size() const
 {
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
     return _size;
 }
 
diff --git a/SPIFBlockDevice.h b/SPIFBlockDevice.h
index 853d0c5796..fceef50f2a 100644
--- a/SPIFBlockDevice.h
+++ b/SPIFBlockDevice.h
@@ -163,6 +163,9 @@ private:
     // Device configuration discovered through sfdp
     bd_size_t _size;
 
+    bool _is_initialized;
+    uint32_t _init_ref_count;
+
     // Internal functions
     int _wren();
     int _sync();