Re: [PATCH] ALSA: ASoC: add codec driver for TI TAS5086

[Daniel Mack <zonque@gmail.com>]

On 22.05.2013 20:01, jonsmirl@gmail.com wrote:
> On Wed, May 22, 2013 at 1:55 PM, Daniel Mack <zonque@gmail.com> wrote:
>> On 22.05.2013 19:50, jonsmirl@gmail.com wrote:
>>> On Fri, Mar 8, 2013 at 6:07 AM, Daniel Mack <zonque@gmail.com> wrote:
>>>> This patch adds a driver for TI's TA5086 6-channel PWM processor.
>>>>
>>>> This chip has a very unusual register layout, specifically because the
>>>> registers are of unequal size, and multi-byte registers require bulk
>>>> writes to take effect. Regmap does not support these kind of mappings.
>>>>
>>>> Currently, the driver does not touch any of the registers >= 0x20, so
>>>> it doesn't matter, because the register map is mapped to an 8-bit array.
>>>> In case more features will be added in the future that require access
>>>> to higher registers, the entire regmap H/W I/O routines have to be
>>>> open-coded.
>>>
>>> Check out my tas5504 driver from a long time ago. It dealt with those registers.
>>>
>>> https://github.com/jonsmirl/mpc5200/blob/master/sound/soc/codecs/tas5504.c
>>> https://github.com/jonsmirl/mpc5200/blob/master/sound/soc/codecs/tas5504.h
>>
>> Sure, without any regmap abstractions, things are somehow manageable.
>> Though you lose all the nice things that regmap gives you, such as
>> hardware independence and caching. I might have a different solution,
>> but I need to get my hands on one of these devices to test.
>>
>> On a slightly different note: why isn't your driver in the mainline kernel?
> 
> TI doesn't make the chip any more.

That might be, but we have tons of drivers for devices in the mainline
kernel which aren't in production anymore.


Daniel