dm: spi: Return 0 if driver does not implement ops->cs_info
If an SPI controller driver does not implement ops->cs_info, that
probably means any chip select number could be valid, hence let's
return 0 for spi_cs_info().
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # SoPine
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
diff --git a/doc/driver-model/spi-howto.rst b/doc/driver-model/spi-howto.rst
index 5540eb7..44eab39 100644
--- a/doc/driver-model/spi-howto.rst
+++ b/doc/driver-model/spi-howto.rst
@@ -634,8 +634,8 @@
device tree will be used to determine what chip selects are valid.
Return -ENODEV if the supplied chip select is invalid, or 0 if it is valid.
-If you don't provide the cs_info() method, -ENODEV is assumed for all
-chip selects that do not appear in the device tree.
+If you don't provide the cs_info() method, 0 is assumed for all chip selects
+that do not appear in the device tree.
Test it
diff --git a/drivers/spi/spi-uclass.c b/drivers/spi/spi-uclass.c
index a4d1b65..9475160 100644
--- a/drivers/spi/spi-uclass.c
+++ b/drivers/spi/spi-uclass.c
@@ -261,11 +261,10 @@
return ops->cs_info(bus, cs, info);
/*
- * We could assume there is at least one valid chip select, but best
- * to be sure and return an error in this case. The driver didn't
- * care enough to tell us.
+ * We could assume there is at least one valid chip select.
+ * The driver didn't care enough to tell us.
*/
- return -ENODEV;
+ return 0;
}
int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,