mtd: m25p80: make command buffer DMA-safe

spi_write() requires the buffer to be DMA-safe, kmalloc()
it seperately to ensure this.

Signed-off-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index 933267a..291d5d9 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -78,7 +78,7 @@
 	struct mtd_info		mtd;
 	unsigned		partitioned:1;
 	u8			erase_opcode;
-	u8			command[CMD_SIZE + FAST_READ_DUMMY_BYTE];
+	u8			*command;
 };
 
 static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd)
@@ -769,6 +769,11 @@
 	flash = kzalloc(sizeof *flash, GFP_KERNEL);
 	if (!flash)
 		return -ENOMEM;
+	flash->command = kmalloc(CMD_SIZE + FAST_READ_DUMMY_BYTE, GFP_KERNEL);
+	if (!flash->command) {
+		kfree(flash);
+		return -ENOMEM;
+	}
 
 	flash->spi = spi;
 	mutex_init(&flash->lock);
@@ -888,8 +893,10 @@
 		status = del_mtd_partitions(&flash->mtd);
 	else
 		status = del_mtd_device(&flash->mtd);
-	if (status == 0)
+	if (status == 0) {
+		kfree(flash->command);
 		kfree(flash);
+	}
 	return 0;
 }