[U-Boot] [PATCH 2/2] dm: spi: Check cs number before accessing slaves

[Bin Meng]

In spi_get_bus_and_cs() only bus number is checked before accessing
slaves. We should check cs number as well.

Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
---

 drivers/spi/spi-uclass.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/spi/spi-uclass.c b/drivers/spi/spi-uclass.c
index 24de0b5..f633eb5 100644
--- a/drivers/spi/spi-uclass.c
+++ b/drivers/spi/spi-uclass.c
@@ -271,6 +271,7 @@ int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
 {
 	struct udevice *bus, *dev;
 	struct dm_spi_slave_platdata *plat;
+	struct spi_cs_info info;
 	bool created = false;
 	int ret;
 
@@ -283,6 +284,11 @@ int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
 		printf("Invalid bus %d (err=%d)\n", busnum, ret);
 		return ret;
 	}
+	ret = spi_cs_info(bus, cs, &info);
+	if (ret) {
+		printf("Invalid cs %d (err=%d)\n", cs, ret);
+		return ret;
+	}
 	ret = spi_find_chip_select(bus, cs, &dev);
 
 	/*
-- 
2.7.4