Re: [PATCH RFC] eeprom: at24: extend driver to plug into the NVMEM framework

[Srinivas Kandagatla <srinivas.kandagatla-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>]

On 17/08/15 16:25, Andrew Lunn wrote:
> On Mon, Aug 17, 2015 at 03:59:23PM +0100, Srinivas Kandagatla wrote:
>>
>>
>> On 17/08/15 14:09, Andrew Lunn wrote:
>>> On Mon, Aug 17, 2015 at 02:01:24PM +0100, Srinivas Kandagatla wrote:
>>>>
>>>> +Adding Maxime in the loop
>>>>
>>>> On 16/08/15 16:37, Stefan Wahren wrote:
>>>>>>> Another question which spring to mind is, do we want the eeprom to be
>>>>>>> in /sys twice, the old and the new way? Backwards compatibility says
>>>>>>> the old must stay. Do we want a way to suppress the new? Or should we
>>>>>>> be going as far as refractoring the code into a core library, and two
>>>>>>> wrapper drivers, old and new?
>>>>> I think these are questions for the framework maintainers.
>>>>>
>>>> One of the reasons for the NVMEM framework is to remove that
>>>> duplicate code in the every driver.  There was no framework/ABI
>>>> which was guiding such old eeprom sysfs entry in first place, so I
>>>> dont see an issue in removing it for good. Correct me if am wrong.
>>>
>>> The reason for keeping it is backwards compatibility. Having the
>>> contents of the EEPROM as a file in /sys via this driver is now a part
>>> of the Linux ABI. You cannot argue it is not an ABI, just because
>>> there is no framework. Userspace will be assuming it exists at the
>>> specified location. So we cannot remove it, for existing uses of the
>>> driver.
>> Am Ok as long as someone is happy to maintain it.
>
> Wolfram Sang has been maintaining the AT24 driver since 2008. We need
> his ACK to this change, and since this is an i2c driver, he is also
> probably the path into mainline for this change.
>
> But we should also look at the bigger picture. The AT25, MAX6875 and
> sunxi_sid drivers also have a binary file in /sys. It would be good to
> have some sort of plan what to do with these drivers, even if at the
> moment only AT24 is under discussion.#

+1


>
>         Andrew
>