Fixed SD card intialization failure

Few SD cards were failing for CMD41 as device was not ready after CMD55.
Added busy delay loop to make sure device is ready and than proceed.

Author: deepikabhavnani

SDBlockDevice.cpp

@@ -690,7 +690,12 @@ int SDBlockDevice::_cmd(SDBlockDevice::cmdSupported cmd, uint32_t arg, bool isAc
     for(int i = 0; i < 3; i++) {
         // Send CMD55 for APP command first
         if (isAcmd) {
-            _cmd_spi(CMD55_APP_CMD, 0x0);
+            response = _cmd_spi(CMD55_APP_CMD, 0x0);
+        }
+
+        // Wait for card to be ready after CMD55
+        if (false == _wait_ready(SD_COMMAND_TIMEOUT)) {
+            debug_if(SD_DBG, "Card not ready yet \n");
         }
 
         // Send command over SPI interface
@@ -710,20 +715,20 @@ int SDBlockDevice::_cmd(SDBlockDevice::cmdSupported cmd, uint32_t arg, bool isAc
     // Process the response R1  : Exit on CRC/Illegal command error/No response
     if (R1_NO_RESPONSE == response) {
         _deselect();
-        debug_if(SD_DBG, "No response CMD:%d \n", cmd);
+        debug_if(SD_DBG, "No response CMD:%d response: 0x%x\n",cmd, response);
         return SD_BLOCK_DEVICE_ERROR_NO_DEVICE;         // No device
     }
     if (response & R1_COM_CRC_ERROR) {
         _deselect();
-        debug_if(SD_DBG, "CRC error CMD:%d \n", cmd);
+        debug_if(SD_DBG, "CRC error CMD:%d response 0x%x \n",cmd, response);
         return SD_BLOCK_DEVICE_ERROR_CRC;                // CRC error
     }
     if (response & R1_ILLEGAL_COMMAND) {
-        debug_if(SD_DBG, "Illegal command CMD:%d\n", cmd);
+        _deselect();
+        debug_if(SD_DBG, "Illegal command CMD:%d response 0x%x\n",cmd, response);
         if (CMD8_SEND_IF_COND == cmd) {                  // Illegal command is for Ver1 or not SD Card
             _card_type = CARD_UNKNOWN;
         }
-        _deselect();
         return SD_BLOCK_DEVICE_ERROR_UNSUPPORTED;      // Command not supported
     }
 
@@ -1024,4 +1029,5 @@ void SDBlockDevice::_deselect() {
     _cs = 1;
     _spi.unlock();
 }
+
 #endif  /* DEVICE_SPI */