Re: [PATCH 2/2] i2c: add support for Socionext SynQuacer I2C controller

From: Andy Shevchenko
Date: Wed Feb 21 2018 - 13:54:28 EST


On Wed, Feb 21, 2018 at 8:20 PM, Ard Biesheuvel
<ard.biesheuvel@xxxxxxxxxx> wrote:
> On 20 February 2018 at 19:39, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote:
>> On Tue, Feb 20, 2018 at 8:04 PM, Ard Biesheuvel
>> <ard.biesheuvel@xxxxxxxxxx> wrote:
>>> On 20 February 2018 at 14:02, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote:

>>>>> + ret = device_property_read_u32(&pdev->dev,
>>>>> + "socionext,pclk-rate",
>>>>> + &i2c->clkrate);
>>>>
>>>> I suppose for ACPI we just register a fixed rate clock and use it in
>>>> the driver in the same way as in OF case.
>>>> I guess at some point we even can provide a generic clock provider for
>>>> ACPI based on rate property.
>>
>>> Is there a question here? Do you want me to change anything?
>>
>> Is it opener for discussion. At least in the drivers we have done for
>> x86 we do the way I described.
>>
>> See, for example, drivers/mfd/intel-lpss.c

> OK, I see what you mean now. But for this driver, creating a fixed
> rate clock with no controls whatsoever, only to interrogate it for its
> rate (which we retrieved from the ACPI device node in the first place)
> seems rather pointless to me. Am I missing something here?

Somehow you are right. That's why I'm thinking that we need to provide
a generic clock provider for such cases.
It's really not a driver business to know the details of resource provider.

--
With Best Regards,
Andy Shevchenko