Re: [PATCH v15 09/12] input: cyapa: add gen5 trackpad device firmware update function support

[Jeremiah Mahler <jmmahler@gmail.com>]

all,

On Tue, Dec 16, 2014 at 12:24:37PM -0800, Benson Leung wrote:
> On Tue, Dec 16, 2014 at 5:56 AM, Jeremiah Mahler <jmmahler@gmail.com> wrote:
> > On Mon, Dec 15, 2014 at 02:23:20PM +0800, Dudley Du wrote:
> >> Add firmware image update function supported for gen5 trackpad device,
> >> it can be used through sysfs update_fw interface.
> >> TEST=test on Chromebooks.
> >>
> >> Signed-off-by: Dudley Du <dudley.dulixin@gmail.com>
> >> ---
> >>  drivers/input/mouse/Kconfig      |   1 +
> >>  drivers/input/mouse/cyapa_gen5.c | 292 ++++++++++++++++++++++++++++++++++++++-
> >>  2 files changed, 292 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/input/mouse/Kconfig b/drivers/input/mouse/Kconfig
> >> index d8b46b0..728490e 100644
> >> --- a/drivers/input/mouse/Kconfig
> >> +++ b/drivers/input/mouse/Kconfig
> >> @@ -206,6 +206,7 @@ config MOUSE_BCM5974
> >>  config MOUSE_CYAPA
> >>       tristate "Cypress APA I2C Trackpad support"
> >>       depends on I2C
> >> +     select CRC_ITU_T
> >>       help
> >
> > Just found out that if I2C_DESIGNWARE_PCI isn't enabled the touchpad
> > won't work.  Verify this on your machines.  Then perhaps add a depends
> > for I2C_DESIGNWARE_PCI instead of I2C since it would include the former.
> 
> This isn't strictly true on all devices, though. This is true on
> DESIGNWARE_PCI based devices like the Acer C720 and the HP Chromebook
> 14, but on other platforms that use Cypress trackpads, such as ARM
> platforms like the Samsung Chromebook Series 3 DESIGNWARE_PCI is not
> required, and will just result in a driver that's never used being
> built.
> 
> The specific I2C bus that's being used here shouldn't matter here...
> that's more of a platform issue. In the case with Chromebooks, it
> might make sense to change drivers/platform/chrome/Kconfig so that
> CHROMEOS_LAPTOP depends on I2C_DESIGNWARE_PCI, maybe.
> 

So DESIGNWARE_PCI isn't required for all devices.  But if MOUSE_CYAPA is
enabled some devices won't work unless I2C_DESIGNWARE_PCI is enabled.  I
wonder if MOUSE_CYAPA should be broken up in to separate working
configurations?  MOUSE_CYAPA_GEN5, MOUSE_CYAPA_GEN3, ?

> -- 
> Benson Leung
> Software Engineer, Chrome OS
> Google Inc.
> bleung@google.com

-- 
- Jeremiah Mahler