Hi Andi,

On Tue, 25 Apr 2017 20:00:56 +0900, Andi Shyti wrote:

quoted

quoted

On Mon, Apr 24, 2017 at 09:42:31AM +0200, Jean Delvare wrote:

So it really boils down to this question: is that chip a generic part
from Cypress, and if so, what is the real part number? Or was is
designed privately by Cypress specifically for Samsung for this one
board (and possibly others to come)?

I knew that the naming was bringing confusion and we had a
previous discussion about it with Chanwoo [1].

This is indeed a generic device from Cypress. The driver has been
ported from Android's Kernel [2]; it says that the device
part is cy8cmbr3xxx, but the datasheet [3] doesn't have any
connection with what the TM2 board has (i.e. the registers don't
match). That's why we suspected that (as you said) this might be
a touch key sensor specifically designed for the TM2 board.

Thanks for the pointers, it helps.

Cypress was not that helpful.

I've been there before with other manufacturers. Chipsets designed
specifically for one hardware vendor are the hardest to support for this
reason.

The alternative was to not provide support, but it didn't look
right.

I agree, you did the right thing by getting the driver upstream. But it
doesn't mean this driver must be enabled in all distribution kernels.

-- 
Jean Delvare
SUSE L3 Support