On 10/14/21 2:24 PM, Simon Glass wrote:
Hi Sean,
On Thu, 14 Oct 2021 at 09:36, Sean Anderson <[email protected]> wrote:
On 10/14/21 11:09 AM, Simon Glass wrote:
> Hi Michal,
>
> On Wed, 6 Oct 2021 at 08:19, Michal Simek <[email protected]> wrote:
>>
>> When DT node has pwm-cells property it shouldn't be bind as timer driver
>> but as PWM driver. That's why make sure that this property is checked.
>>
>> Signed-off-by: Michal Simek <[email protected]>
>> ---
>>
>> Changes in v3:
>> - New patch in series
>>
>> drivers/timer/cadence-ttc.c | 12 ++++++++++++
>> 1 file changed, 12 insertions(+)
>>
>
> Why not have two compatible strings?
As I understand it, because the hardware is the same, it should have the
same compatible string.
>> diff --git a/drivers/timer/cadence-ttc.c b/drivers/timer/cadence-ttc.c
>> index 2f95d45ecd7a..2eff45060ad6 100644
>> --- a/drivers/timer/cadence-ttc.c
>> +++ b/drivers/timer/cadence-ttc.c
>> @@ -97,6 +97,17 @@ static int cadence_ttc_of_to_plat(struct udevice *dev)
>> return 0;
>> }
>>
>> +static int cadence_ttc_bind(struct udevice *dev)
>> +{
>> + const char *cells;
>> +
>> + cells = dev_read_prop(dev, "#pwm-cells", NULL);
>> + if (cells)
>> + return -ENODEV;
>
> We can read properties in bind() when necessary, but this is very
> strange...it seems like the bindings are messed up?
This is the preferred way to select between a PWM and a timer driver.
See e.g. Rob's comment for xlnx,pwm at [1].
I actually don't understand his comment. Is it the 'No...' one?
No, it's the
If a PWM, perhaps you want a '#pwm-cells' property which can serve as
the hint to configure as a PWM.
--Sean
Anyway, it seems you understand what you are doing, and this is
supposed to be supported by driver model.
Reviewed-by: Simon Glass <[email protected]>
Regards,
Simon
