From 4fbad92e7382c74757a58491deb6d210d1d842db Mon Sep 17 00:00:00 2001 From: Peng Fan Date: Fri, 20 Mar 2015 13:19:16 +0800 Subject: [PATCH] mtd: spi: check return value of spi_setup_slave Need to check value of spi_setup_slave and spi_setup_slave_fdt. If their return value 'bus' is NULL, there is no need to pass it to following spi_flash_probe_tail. If 'bus' is null, the original function flow is as following: spi_flash_probe |->spi_setup_slave |->spi_probe_bus_tail |->spi_flash_probe_slave |->spi_free_slave Alougth check the pointer in spi_free_slave is ok, checking the return value of spi_setup_slave and spi_setup_slave_fdt is better. Before this fix: " => sf probe 0:2 FSL_QSPI: Not a valid cs ! SF: Failed to set up slave data abort pc : [] lr : [] reloc pc : [<87814dcc>] lr : [<8782428c>] sp : fdf4fcf0 ip : e630396c fp : fe0d0888 r10: fffa2538 r9 : fdf4feb8 r8 : 02625a00 r7 : 00000002 r6 : fff94ec0 r5 : 00000000 r4 : 9355553c r3 : 1af0593c r2 : cb3fe030 r1 : fff94eb8 r0 : e59ff018 Flags: nZCv IRQs off FIQs off Mode SVC_32 Resetting CPU ... " After this fix: " => sf probe 0:2 FSL_QSPI: Not a valid cs ! Failed to initialize SPI flash at 0:2 " No data abort using this patch. Signed-off-by: Peng Fan Reviewed-by: Jagannadha Sutradharudu Teki --- drivers/mtd/spi/sf_probe.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/mtd/spi/sf_probe.c b/drivers/mtd/spi/sf_probe.c index d19138d..2ee228d 100644 --- a/drivers/mtd/spi/sf_probe.c +++ b/drivers/mtd/spi/sf_probe.c @@ -434,6 +434,8 @@ struct spi_flash *spi_flash_probe(unsigned int busnum, unsigned int cs, struct spi_slave *bus; bus = spi_setup_slave(busnum, cs, max_hz, spi_mode); + if (!bus) + return NULL; return spi_flash_probe_tail(bus); } @@ -444,6 +446,8 @@ struct spi_flash *spi_flash_probe_fdt(const void *blob, int slave_node, struct spi_slave *bus; bus = spi_setup_slave_fdt(blob, slave_node, spi_node); + if (!bus) + return NULL; return spi_flash_probe_tail(bus); } #endif