On 11/4/23 19:13, Andre Przywara wrote:
On Sat, 4 Nov 2023 09:00:07 +0200
Heinrich Schuchardt <heinrich.schucha...@canonical.com> wrote:
Hi Heinrich,
many thanks for finding and fixing this!
In different parts of our code we assume that the first RNG device is the
one to be used. Therefore it is preferable to detect the availability of
the RNDR register already in the bind method.
For signaling the non-existence of a device the driver model requires using
ENOENT (and not ENODEV).
Doh, now I feel silly! I thought I checked the call path, and looked at
initcall_run_list(), which prints the error message, and suggests that
only 0 would be acceptable.
But indeed -ENOENT works, with the slight caveat of printing:
================
No match for driver 'arm-rndr'
Some drivers were not found
The message texts are definitively wrong. They should be:
No device for driver 'arm-rndr'.
Some devices not found.
@Simon
I think we should make these messages log_debug().
Best regards
Heinrich
================
But it's definitely an improvement over the current situation, and I
don't feel like boiling the DM ocean for this stupid little driver.
Fixes: 31565bb0aa2d ("driver: rng: Add DM_RNG interface for ARMv8.5 RNDR
registers")
Signed-off-by: Heinrich Schuchardt> <heinrich.schucha...@canonical.com>
Reviewed-by: Andre Przywara <andre.przyw...@arm.com>
Tested-by: Andre Przywara <andre.przyw...@arm.com>
Many thanks!
Andre
---
drivers/rng/arm_rndr.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/rng/arm_rndr.c b/drivers/rng/arm_rndr.c
index 55989743ea..4512330e68 100644
--- a/drivers/rng/arm_rndr.c
+++ b/drivers/rng/arm_rndr.c
@@ -62,10 +62,10 @@ static const struct dm_rng_ops arm_rndr_ops = {
.read = arm_rndr_read,
};
-static int arm_rndr_probe(struct udevice *dev)
+static int arm_rndr_bind(struct udevice *dev)
{
if (!cpu_has_rndr())
- return -ENODEV;
+ return -ENOENT;
return 0;
}
@@ -74,7 +74,7 @@ U_BOOT_DRIVER(arm_rndr) = {
.name = DRIVER_NAME,
.id = UCLASS_RNG,
.ops = &arm_rndr_ops,
- .probe = arm_rndr_probe,
+ .bind = arm_rndr_bind,
};
U_BOOT_DRVINFO(cpu_arm_rndr) = {
