[alsa-devel] [PATCH] ASoC: Add device tree binding for WM8753

[Barry Song]

2011/8/10 Mark Brown <broonie at opensource.wolfsonmicro.com>:
> On Wed, Aug 10, 2011 at 09:21:16AM +0800, Barry Song wrote:
>> 2011/8/9 Mark Brown <broonie at opensource.wolfsonmicro.com>:
>
>> > Oh, if that's the case the driver ought to have device tree bindings
>> > which replicate the platform data.  Unless the platform data is
>> > sufficiently obscure for hardly anyone to want to use it I guess.
>
>> I guess what Dmitry said is the big ads7846_platform_data structure.
>
> Yes.
>
>>  struct ads7846_platform_data {
>>         u16     model;                  /* 7843, 7845, 7846, 7873. */
>>         u16     vref_delay_usecs;       /* 0 for external vref; etc */
>>         u16     vref_mv;                /* external vref value, milliVolts
>>                                          * ads7846: if 0, use internal vref */
>>         bool    keep_vref_on;           /* set to keep vref on for differential
>>                                          * measurements as well */
>>         bool    swap_xy;                /* swap x and y axes */
>
> ...
>
>> The structure even has some callbacks which can't be possible in dts.
>
> There's some callbacks but the bulk of the structure (including the bits
> I quoted above for example) looks like it's pure data and could sensibly
> be represented in the device tree.

there have been many discussions about what should be in dts.
basically, hardware information should be in dts, but data required by
driver implementation should be not in dts.
There are a lot of fields in the structure, not all can be a property
as hardware information in dts. That means the driver need a lot of
changes then.

>