Hello, On 08/04/2014 05:42 PM, Doug Anderson wrote: > > >> For the touchpad it seems DT support has landed in the input tree as >> "atmel,maxtouch". Backporting just that patch does not make it work >> though. (Tried the rejected pinctrl approach to be on the safe side.) >> https://code.google.com/p/chromium/issues/detail?id=371114 >> https://patchwork.kernel.org/patch/3976801/ > > This is the same work as needed for pit and pi, I believe. Perhaps > Javier or Dmitry has this on their todo list? > > I posted a couple of patches that allowed me to have the atmel touchpad working on Peach Pit. I found two issues while testing the driver: a) The device keycode event capabilities are hardcoded in the downstream Chrome OS driver while the mainline driver expect these to be defined in the DT. The property is called "linux,gpio-keymap" since it seems that the actual implementation is using a set of GPIOs. But this is handled by the firmware since the kernel just read a status register from the atmel T9 object. I found the property confusing at first since it didn't have anything to do with Linux GPIO so posted a patch to add an example to the DT binding doc in order to make it easier to understand [0]. b) The driver overwrites the edge/level flags parsed by OF core and expects that the IRQ type will be passed using platform data. The downstream Chrome OS driver defaults the type to IRQF_TRIGGER_FALLING if this is not provided while the mainline does not have a default so it's just 0 (IRQ_TYPE_NONE). This is fixed by reading back the IRQ type from the struct irq_data when parsing the DT data [1]. The DTS changes to make the atmel touchpad work on Peach Pit were posted in [2]. Changes for Pi were included as well since it should be the same but it was not tested since I don't have access to that machine, testing will be highly appreciated. > > -Doug > Thanks a lot and best regards, Javier [0]: https://lkml.org/lkml/2014/8/6/584 [1]: https://lkml.org/lkml/2014/8/7/82 [2]: https://lkml.org/lkml/2014/8/6/589 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
