Hi Simon,
On 04/05/21 10:28 pm, Simon Glass wrote:
> Hi Kishon,
>
> On Tue, 4 May 2021 at 04:42, Kishon Vijay Abraham I <kis...@ti.com> wrote:
>>
>> The reset framework provides devm_reset_control_get_optional()
>> which can return NULL (not an error case). So all the other reset_ops
>> should handle NULL gracefully. Prepare the way for a managed reset
>> API by handling NULL pointers without crashing nor failing.
>>
>> Signed-off-by: Vignesh Raghavendra <vigne...@ti.com>
>> Signed-off-by: Kishon Vijay Abraham I <kis...@ti.com>
>> ---
>> drivers/reset/reset-uclass.c | 35 ++++++++++++++++++++++++++++++-----
>> 1 file changed, 30 insertions(+), 5 deletions(-)
>
> I am still not a fan of this. There is no way to know whether the
> reset API call actually did anything. Normally we return -EINVAL or
> something like that when the value is invalid (e.g. see GPIO uclass).
The reset modification is more in-line with how clk uclass is designed.
There every API first checks if the clock is valid and returns 0 (will
be the case for optional clocks)
if (!clk_valid(clk))
return 0;
If you don't prefer this approach, I'll drop this patch and handle it
appropriately in the client driver (serdes driver). Please let me know.
>
> The function you mention says: * Returns a struct reset_ctl or a
> dummy reset controller if it failed.
>
> But it does not appear to do that?
Right, looks like it's incorrect from when the patch was actually
introduced. It was returning "NULL" for optional resets.
commit 139e4a1cbe60de96d4febbc6db5882929801ca46
Author: Jean-Jacques Hiblot <jjhib...@ti.com>
Date: Wed Sep 9 15:37:03 2020 +0530
drivers: reset: Add a managed API to get reset controllers from the DT
Thanks
Kishon
