Re: [PATCH v2] platform/chrome: chromeos_laptop - do not probe devices on Pixel 1

[Dmitry Torokhov]

On Fri, Apr 10, 2015 at 10:41:54AM -0700, Dmitry Torokhov wrote:
> On Thu, Apr 09, 2015 at 04:57:59PM -0700, Dmitry Torokhov wrote:
> > Atmel MXT devices use different i2c addresses, depending on the current
> > mode of operation (bootloader or application). The new Atmel MXT driver
> > expects i2c client's address contain the application address of the
> > chip, and calculates the expected bootloader address form the
> > application address. Unfortunately chromeos_laptop does probe the
> > devices and if touchpad (or touchscreen, or both) comes up in bootloader
> > mode, the i2c device gets instantiated with the bootloader address
> > instead of application address, which confuses the driver.
> > 
> > Given that hardware on Pixel is set and is not going to change let's not
> > try to probe devices to see if they are present or not, but rather
> > instantiate them always at expected addresses.
> > 
> > Since all devices are now probed and/or instantiated at given address,
> > we no longer need to support probing multiple addresses for the same
> 
> Hmm, that strategy won't work on C720 since there are devices with touchscreen
> and without one, so we do want to probe but always instantiate at primary
> address. V3 will be upcoming...

OK, new version. Not sending to the wide world for now in case we decide
it is too ugly...