[PATCH v4 2/2] pwm: rockchip: Added to support for RK3288 SoC

Doug Anderson dianders at chromium.org
Wed Aug 6 20:46:17 PDT 2014


Caesar,

On Wed, Aug 6, 2014 at 8:37 PM, caesar <caesar.wang at rock-chips.com> wrote:
> Doug,
>
> 在 2014年08月07日 11:26, Doug Anderson 写道:
>
>> caesar,
>>
>> On Wed, Aug 6, 2014 at 8:23 PM, caesar <caesar.wang at rock-chips.com> wrote:
>>>
>>> 在 2014年08月07日 10:16, Doug Anderson 写道:
>>>
>>>> Caesar,
>>>>
>>>> On Wed, Aug 6, 2014 at 6:27 PM, caesar <caesar.wang at rock-chips.com>
>>>> wrote:
>>>>>
>>>>> Doug,
>>>>>
>>>>> 在 2014年08月07日 06:46, Doug Anderson 写道:
>>>>>
>>>>>> Caesar,
>>>>>>
>>>>>> On Thu, Jul 24, 2014 at 3:21 AM, Caesar Wang
>>>>>> <caesar.wang at rock-chips.com>
>>>>>> wrote:
>>>>>>>
>>>>>>> +static const struct rockchip_pwm_data pwm_data_v1 = {
>>>>>>> +       .regs.duty = PWM_HRC,
>>>>>>> +       .regs.period = PWM_LRC,
>>>>>>> +       .regs.cntr = PWM_CNTR,
>>>>>>> +       .regs.ctrl = PWM_CTRL,
>>>>>>> +       .prescaler = PRESCALER,
>>>>>>> +       .set_enable = rockchip_pwm_set_enable_v1,
>>>>>>> +};
>>>>>>> +
>>>>>>> +static const struct rockchip_pwm_data pwm_data_v2 = {
>>>>>>> +       .regs.duty = PWM_LRC,
>>>>>>> +       .regs.period = PWM_HRC,
>>>>>>> +       .regs.cntr = PWM_CNTR,
>>>>>>> +       .regs.ctrl = PWM_CTRL,
>>>>>>> +       .prescaler = PRESCALER-1,
>>>>>>> +       .set_enable = rockchip_pwm_set_enable_v2,
>>>>>>> +};
>>>>>>> +
>>>>>>> +static const struct rockchip_pwm_data pwm_data_vop = {
>>>>>>> +       .regs.duty = PWM_LRC,
>>>>>>> +       .regs.period = PWM_HRC,
>>>>>>> +       .regs.cntr = PWM_CTRL,
>>>>>>> +       .regs.ctrl = PWM_CNTR,
>>>>>>
>>>>>> Did you really mean to flip CTRL and CNTR here?  If so, that's super
>>>>>> confusing and deserves a comment.  AKA, I think the above should not
>>>>>> be:
>>>>>>
>>>>>>     +       .regs.cntr = PWM_CTRL,
>>>>>>     +       .regs.ctrl = PWM_CNTR,
>>>>>>
>>>>>> ...but should be
>>>>>>
>>>>>>     +       .regs.cntr = PWM_CNTR,
>>>>>>     +       .regs.ctrl = PWM_CTRL,
>>>>>>
>>>>>> If you didn't mean to flip CTRL and CNTR here, then just get rid of
>>>>>> pwm_data_vop and refer to pwm_data_v2.  In fact, I'd suggest that you
>>>>>> totally remove the "rockchip,vop-pwm" since there's nothing different
>>>>>> between "rockchip,rk3288-pwm" and "rockchip,vop-pwm".
>>>>>
>>>>>
>>>>> Sorry,I think it's no problem. the  "rockchip,rk3288-pwm" and
>>>>> "rockchip,vop-pwm" are seperate PWM controllers.
>>>>> They are just different registers address between CNTR and CTRL .
>>>>
>>>> OK, I looked up in the TRM.  Right, the CNTR and CTRL are flipped on
>>>> the vop.  So I think that the only change you need is to add:
>>>>
>>>> #define PWM_VOP_CTRL  0x00
>>>> #define PWM_VOP_CNTR  0x0c
>>>>
>>>> ...then use these new #defines for the vop structure.
>>>>
>>>>
>>>> As you have the code written right now it's very confusing.  The new
>>>> #defines will fix this.
>>>>
>>> yeah, I think they can be used in the same context.
>>>
>>> I will fix it in patch v5 if it is really need.
>>
>> I think you should fix this, but if Thierry doesn't think so then it's
>> really his decision.
>
> I remember In patch v2 [1],Thierry suggests me to fix it so if I have no to
> get wrong.
>
> [1]: https://lkml.org/lkml/2014/7/21/113

I think Thierry might not have realized that they were flipped...

-Doug



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