[U-Boot] [PATCH] mtd: spi-nor-core: Fix static checker warnings

[Vignesh Raghavendra <vigneshr@ti.com>]

Static checker warns 'ret' variable may be used uninitialized in
spi_nor_erase() and spi_nor_write() in case of zero length requests.
Fix these warnings by checking for zero length requests and returning
early.

Reported-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
---
 drivers/mtd/spi/spi-nor-core.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
index 9b726be5d22d..87bcb63347ce 100644
--- a/drivers/mtd/spi/spi-nor-core.c
+++ b/drivers/mtd/spi/spi-nor-core.c
@@ -550,6 +550,9 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
 	dev_dbg(nor->dev, "at 0x%llx, len %lld\n", (long long)instr->addr,
 		(long long)instr->len);
 
+	if (!instr->len)
+		return 0;
+
 	div_u64_rem(instr->len, mtd->erasesize, &rem);
 	if (rem)
 		return -EINVAL;
@@ -1230,6 +1233,9 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
 
 	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
 
+	if (!len)
+		return 0;
+
 	for (i = 0; i < len; ) {
 		ssize_t written;
 		loff_t addr = to + i;
-- 
2.24.0