Re: [PATCH] spi: davinci: Use of_device_get_match_data() helper

["tiantao (H)" <tiantao6@huawei.com>]

在 2021/3/30 19:56, Fabio Estevam 写道:
> On Mon, Mar 29, 2021 at 9:54 PM tiantao (H) <tiantao6@huawei.com> wrote:
>
>> Even with of_match_device, there is still a type conversion，as follows
>>
>> spi_data = (struct davinci_spi_of_data *)match->data;
>>
>> Using of_device_get_match_data instead of of_match_device doesn't look
>> like a problem from the code, other spi drivers do the same thing
> What about doing it like this?
thanks.

 From what I have tested, the results are ok. I will send v2 to fix.

make modules M=drivers/spi/
   CC [M]  drivers/spi//spi-davinci.o
drivers/spi//spi-davinci.c: In function ‘spi_davinci_get_pdata’:
drivers/spi//spi-davinci.c:826:11: warning: assignment discards ‘const’ 
qualifier from pointer target type [-Wdiscarded-qualifiers]
   826 |  spi_data = of_device_get_match_data(&pdev->dev);
       |           ^
   MODPOST drivers/spi//Module.symvers

   LD [M]  drivers/spi//spi-davinci.ko

  vim drivers/spi//spi-davinci.c
make modules M=drivers/spi/
   CC [M]  drivers/spi//spi-davinci.o
   MODPOST drivers/spi//Module.symvers
   LD [M]  drivers/spi//spi-davinci.ko
>
> --- a/drivers/spi/spi-davinci.c
> +++ b/drivers/spi/spi-davinci.c
> @@ -817,18 +817,13 @@ static int spi_davinci_get_pdata(struct
> platform_device *pdev,
>                          struct davinci_spi *dspi)
>   {
>          struct device_node *node = pdev->dev.of_node;
> -       struct davinci_spi_of_data *spi_data;
> +       const struct davinci_spi_of_data *spi_data;
>          struct davinci_spi_platform_data *pdata;
>          unsigned int num_cs, intr_line = 0;
> -       const struct of_device_id *match;
>
>          pdata = &dspi->pdata;
>
> -       match = of_match_device(davinci_spi_of_match, &pdev->dev);
> -       if (!match)
> -               return -ENODEV;
> -
> -       spi_data = (struct davinci_spi_of_data *)match->data;
> +       spi_data = device_get_match_data(&pdev->dev);
>
>          pdata->version = spi_data->version;
>          pdata->prescaler_limit = spi_data->prescaler_limit;
> .
>