[PATCH 1/3] mfd: tps6586x: add version detection

[Stefan Agner]

Am 2013-11-27 16:30, schrieb Lee Jones:
> On Wed, 27 Nov 2013, Stefan Agner wrote:
> 
>> Am 2013-11-27 15:36, schrieb Lee Jones:
>> <snip>
>> >> Perhaps I should suggest to make TPS6586X_ANY a positive number then,
>> >> as a negative value to me indicates more of an error than a generic
>> >> parameter.
>> I see, its especially confusing since the version is filled using the
>> i2c_smbus_read_byte_data functions return value. The version field is a
>> 8-Bit value according to the data sheet, I could use 0x100 as
>> TPS6586X_ANY identifier.
> 
> How far are we away from using 0xFF?
> 
> I'd be happy to use that and change it _if_ we ever get close.
> 
> If it's likely that it'll be used, then sure 0x100 sounds okay too.

Yes, I thought about 0xFF too. The latest device we support is TPS658643
(according to data sheet release dates), which has the smallest version
number (03). Since it seems to be a CRC (hence VERSIONCRC) the number is
quite random. Also, 0xFF sounds like a bitmask which can mask all
versions, but the versions can't be used bitwise... So I would prefer to
go with 0x100.