Re: [RFC PATCH 0/2] check I2C device id for pca984x chips

[Peter Rosin <peda@axentia.se>]

On 2018-01-29 18:38, Adrian Fiergolski wrote:
>>> On 22.01.2018 at 12:36, Peter Rosin wrote:
>>>> This series tries to check the I2C device id, but instead of open
>>>> coding the check in the pca954x driver, I have a new function in
>>>> the core doing the work.
>>>>
>>>> The code is only compile-tested, hence the RFC, and I would really
>>>> like a Tested-by: tag from Adrian who presumably have one of these
>>>> chips.
>>>>
>>>> Also, I'm not sure if I should list all manufacturers that I know
>>>> about in the header, or if I should settle for the one that is
>>>> actually used and leave the others to be added by whomever needs
>>>> them...
>>>>
>>>> Cheers,
>>>> peda
>>>>
>>>> Peter Rosin (2):
>>>>   i2c: add i2c_get_device_id() to get the standard i2c device id
>>>>   i2c: mux: pca954x: verify the device id of the pca984x chips
>>>>
>>>>  drivers/i2c/i2c-core-base.c         | 33 ++++++++++++++++++++++++++++
>>>>  drivers/i2c/muxes/i2c-mux-pca954x.c | 43 +++++++++++++++++++++++++++++++++++++
>>>>  include/linux/i2c.h                 | 30 ++++++++++++++++++++++++++
>>>>  3 files changed, 106 insertions(+)
>>>>
> Hi Peter,
> 
> I have tested your patch with the pca9846 device and I confirm it works.
> Moreover, after short debugging, I can confirm that all read ids
> (manufacture, part and die) seem to be correct. Moreover, in case of
> misconfiguration, the probe function return a proper message and fails
> as expected.

Excellent, thanks!

I'll ping Wolfram later on for any input on the core changes (if needed),
but let's wait until the 4.16 merge-window closes and things settle down
a bit. This will land in 4.17 at the earliest.

Cheers,
Peter