[PATCH] spi: amlogic-spisg: drop misleading NULL check on exdesc

From: Stepan Ionichev

Date: Wed May 06 2026 - 14:38:32 EST


aml_spisg_setup_transfer() takes a non-NULL exdesc pointer; the
function dereferences exdesc unconditionally later in the body to
populate the SPI scatter-gather descriptors (tx_ccsg / rx_ccsg).
The sole caller, aml_spisg_transfer_one_message(), always passes a
valid pointer derived from kcalloc().

The "if (exdesc)" guard around the memset() at the start of the
function is therefore dead and misleading -- it suggests callers
may pass NULL when in fact they may not. smatch flags the
inconsistency:

drivers/spi/spi-amlogic-spisg.c:314 aml_spisg_setup_transfer()
error: we previously assumed 'exdesc' could be null (see line 261)

Drop the check; the unconditional memset matches the unconditional
dereferences elsewhere in the function and removes the inconsistency
that smatch reports.

No functional change.

Signed-off-by: Stepan Ionichev <sozdayvek@xxxxxxxxx>
---
drivers/spi/spi-amlogic-spisg.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/spi/spi-amlogic-spisg.c b/drivers/spi/spi-amlogic-spisg.c
index 19c5eba41..b2a916496 100644
--- a/drivers/spi/spi-amlogic-spisg.c
+++ b/drivers/spi/spi-amlogic-spisg.c
@@ -258,8 +258,7 @@ static int aml_spisg_setup_transfer(struct spisg_device *spisg,
int ret;

memset(desc, 0, sizeof(*desc));
- if (exdesc)
- memset(exdesc, 0, sizeof(*exdesc));
+ memset(exdesc, 0, sizeof(*exdesc));
aml_spisg_set_speed(spisg, xfer->speed_hz);
xfer->effective_speed_hz = spisg->effective_speed_hz;

--
2.43.0