sf: probe: Add support for flag status polling

From Micron, 512MB onwards, flash requires to poll flag status
instead of read status- hence added E_FSR flag on spectific
flash parts.

Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
diff --git a/drivers/mtd/spi/spi_flash_probe.c b/drivers/mtd/spi/spi_flash_probe.c
index 9c2e115..8ea6915 100644
--- a/drivers/mtd/spi/spi_flash_probe.c
+++ b/drivers/mtd/spi/spi_flash_probe.c
@@ -94,10 +94,10 @@
 	{"N25Q128A",	   0x20bb18, 0x0,       64 * 1024,   256,	       SECT_4K},
 	{"N25Q256",	   0x20ba19, 0x0,       64 * 1024,   512,	       SECT_4K},
 	{"N25Q256A",	   0x20bb19, 0x0,       64 * 1024,   512,	       SECT_4K},
-	{"N25Q512",	   0x20ba20, 0x0,       64 * 1024,  1024,	       SECT_4K},
-	{"N25Q512A",	   0x20bb20, 0x0,       64 * 1024,  1024,	       SECT_4K},
-	{"N25Q1024",	   0x20ba21, 0x0,       64 * 1024,  2048,	       SECT_4K},
-	{"N25Q1024A",	   0x20bb21, 0x0,       64 * 1024,  2048,	       SECT_4K},
+	{"N25Q512",	   0x20ba20, 0x0,       64 * 1024,  1024,      E_FSR | SECT_4K},
+	{"N25Q512A",	   0x20bb20, 0x0,       64 * 1024,  1024,      E_FSR | SECT_4K},
+	{"N25Q1024",	   0x20ba21, 0x0,       64 * 1024,  2048,      E_FSR | SECT_4K},
+	{"N25Q1024A",	   0x20bb21, 0x0,       64 * 1024,  2048,      E_FSR | SECT_4K},
 #endif
 #ifdef CONFIG_SPI_FLASH_SST		/* SST */
 	{"SST25VF040B",	   0xbf258d, 0x0,	64 * 1024,     8,     SECT_4K | SST_WP},
@@ -187,7 +187,6 @@
 
 	flash->spi = spi;
 	flash->name = params->name;
-	flash->poll_cmd = CMD_READ_STATUS;
 
 	/* Assign spi_flash ops */
 	flash->write = spi_flash_cmd_write_multi;
@@ -215,6 +214,13 @@
 		flash->erase_size = flash->sector_size;
 	}
 
+	/* Poll cmd seclection */
+	flash->poll_cmd = CMD_READ_STATUS;
+#ifdef CONFIG_SPI_FLASH_STMICRO
+	if (params->flags & E_FSR)
+		flash->poll_cmd = CMD_FLAG_STATUS;
+#endif
+
 	/* Flash powers up read-only, so clear BP# bits */
 #if defined(CONFIG_SPI_FLASH_ATMEL) || \
 	defined(CONFIG_SPI_FLASH_MACRONIX) || \
diff --git a/include/spi_flash.h b/include/spi_flash.h
index 0d40e6c..09af55d 100644
--- a/include/spi_flash.h
+++ b/include/spi_flash.h
@@ -20,6 +20,7 @@
 /* SECT flags */
 #define SECT_4K		(1 << 1)
 #define SECT_32K		(1 << 2)
+#define E_FSR			(1 << 3)
 
 /* SST specific macros */
 #ifdef CONFIG_SPI_FLASH_SST