mtd: spi: Fix page size for S25FL032P,S25FL064P

The commit 6af8dc3ebc broke support for
S25FL032P and S25FL064P by carelessly removing the code handling special
page size for these two SPI NOR flashes and unifying the code under the
assumption that Extended JEDEC ID of 0x4d00 always implies 512b page size.

Add special case handling for these two SPI NOR flashes.

Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>

drivers/mtd/spi/sf_probe.c

@@ -146,7 +146,21 @@ static struct spi_flash *spi_flash_validate_params(struct spi_slave *spi,
 
 	/* Compute the flash size */
 	flash->shift = (flash->dual_flash & SF_DUAL_PARALLEL_FLASH) ? 1 : 0;
-	flash->page_size = ((ext_jedec == 0x4d00) ? 512 : 256) << flash->shift;
+	/*
+	 * The Spansion S25FL032P and S25FL064P have 256b pages, yet use the
+	 * 0x4d00 Extended JEDEC code. The rest of the Spansion flashes with
+	 * the 0x4d00 Extended JEDEC code have 512b pages. All of the others
+	 * have 256b pages.
+	 */
+	if (ext_jedec == 0x4d00) {
+		if ((jedec == 0x0215) || (jedec == 0x216))
+			flash->page_size = 256;
+		else
+			flash->page_size = 512;
+	} else {
+		flash->page_size = 256;
+	}
+	flash->page_size <<= flash->shift;
 	flash->sector_size = params->sector_size << flash->shift;
 	flash->size = flash->sector_size * params->nr_sectors << flash->shift;
 #ifdef CONFIG_SF_DUAL_FLASH