Re: [PATCH v2 1/2] spi: Add Renesas R-Car Gen3 RPC SPI controller driver

From: Marek Vasut
Date: Wed Dec 05 2018 - 07:57:56 EST


On 12/05/2018 10:11 AM, Geert Uytterhoeven wrote:
> Hi Mason,
>
> On Wed, Dec 5, 2018 at 8:44 AM <masonccyang@xxxxxxxxxxx> wrote:
>>> "Marek Vasut" <marek.vasut@xxxxxxxxx>
>>> 2018/12/05 äå 10:04
>>> On 12/03/2018 10:18 AM, Mason Yang wrote:
>>>> Add a driver for Renesas R-Car Gen3 RPC SPI controller.
>>>>
>>>> Signed-off-by: Mason Yang <masonccyang@xxxxxxxxxxx>
>
>>>> +static u8 rpc_bits_xfer(u32 nbytes)
>>>> +{
>>>> + if (nbytes > 4)
>>>> + nbytes = 4;
>>>
>>> Use clamp() ?
>>>
>>
>> nbytes = clamp(nbytes, 1, 4);
>>
>> got many warnings, something like,
>> ./include/linux/kernel.h:845:29: warning: comparison of distinct pointer types lacks a cast
>
> You can either make the constants unsigned (1U and 4U), or
> use clamp_t(u32, ...).
>
>>>> + rpc->smenr |= RPC_SMENR_SPIDE(rpc_bits_xfer
>>>> + (op->data.nbytes)) | RPC_SMENR_SPIDB
>>>> + (fls(op->data.buswidth >> 1));
>>>
>>> Drop parenthesis around fls()
>>
>> ?
>> no way.
>
> Please split the line before RPC_SMENR_SPIDB, and join the next line
> with the parameters, so it becomes obvious the parentheses are needed
> because RPC_SMENR_SPIDB() is a macro taking parameters.

Oh, I didn't notice that, right.

--
Best regards,
Marek Vasut