[PATCH 5.4 194/222] mtd: cfi_cmdset_0002: only check errors when ready in cfi_check_err_status()

Greg Kroah-Hartman
2020-01-22T13:28:43Z

From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

commit 72914a8cff7e1d910c58e125e15a0da409e3135f upstream.

Cypress S26K{L|S}P{128|256|512}S datasheet says that the error bits in
the status register are only valid when the "device ready" bit 7 is set.
Add the check for the device ready bit in cfi_check_err_status() as that
function isn't always called with this bit set.

Fixes: 4844ef80305d ("mtd: cfi_cmdset_0002: Add support for polling status register")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/mtd/chips/cfi_cmdset_0002.c | 4 ++++
1 file changed, 4 insertions(+)

--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -136,6 +136,10 @@ static void cfi_check_err_status(struct
cfi->device_type, NULL);
status = map_read(map, adr);

+ /* The error bits are invalid while the chip's busy */
+ if (!map_word_bitsset(map, status, CMD(CFI_SR_DRB)))
+ return;
+
if (map_word_bitsset(map, status, CMD(0x3a))) {
unsigned long chipstatus = MERGESTATUS(status);