spi: mxs: Introduce spi_cs_is_valid()
Introduce spi_cs_is_valid() for validating spi bus and chip select numbers.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Marek Vasut <marex@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c
index 4e6f14e..e7237e7 100644
--- a/drivers/spi/mxs_spi.c
+++ b/drivers/spi/mxs_spi.c
@@ -51,14 +51,23 @@
{
}
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+ /* MXS SPI: 4 ports and 3 chip selects maximum */
+ if (bus > 3 || cs > 2)
+ return 0;
+ else
+ return 1;
+}
+
struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int mode)
{
struct mxs_spi_slave *mxs_slave;
uint32_t addr;
- if (bus > 3) {
- printf("MXS SPI: Max bus number is 3\n");
+ if (!spi_cs_is_valid(bus, cs)) {
+ printf("mxs_spi: invalid bus %d / chip select %d\n", bus, cs);
return NULL;
}