On Wed, Jul 12, 2017 at 02:40:20PM +0530, Sharma, Jitendra wrote:
> Hi,
>
> I am working on a android project. Here, I want to enable Remote control
> support on one of our custom msm chipset based board.
>
> The idea is, once board boot up, then via HDMI over HDMI monitor we will see
> android UI, and we want to browse through that UI using any standard
> protocol(like RC6 or nec) based remote
>
> For enabling remote control support, I followed below steps:
>
> 1) Enabled RC support for driver compilation in our defconfig file like:
>
> +CONFIG_MEDIA_RC_SUPPORT=y
> +CONFIG_RC_DEVICES=y
> +CONFIG_IR_GPIO_CIR=y
>
> 2) We have one RC6 philips remote. So, we created keycode file using
> scancodes and used that keycode file for device node mentioned below.
>
> 3) As IR receiver is connected via gpio over our custom board, so we add a
> device tree entry like:
>
> + ir: ir-receiver {
> + compatible = "gpio-ir-receiver";
> + gpios = <&tlmm 120 1>;
> + linux,rc-map-name = "rc-rc6-philips"; /*rc-rc6-philips is
> the keycode file for one RC6 protocol based file*/
> + };
> 4) Finally create boot.img and flash it onto board
>
> Now our observation with above created boot.img is as follows:
>
> 1) We boot up without HDMI connected (For our case till we not connect HDMI,
> android userspace won't come up).
>
> 2) Via getevent tool, we could see remote events coming up proper . This is
> Good case
>
> 3) Now we connect HDMI (after connecting HDMI, android userspace gets up).
> We observed that via getevent tool, no event is coming up even after
> multiple remote key presses. This is bad case
>
> I enabled IR_dprintk and for this bad case, I observed that for each key
> press, below logs appear continously:
>
> [ 128.208417] sample: (0us space)
> [ 128.211341] sample: (0us space)
> [ 128.211683] sample: (0us space)
> [ 128.212180] sample: (0us space)
>
> And then eventually RC6 decoder function fails in very early stage.
Looking at that, I would guess that the edge trigger on the gpio pin
is firing at the right time, but gpio_get_value() is not returning
the correct value, so a space get passed every time rather than pulse
and space.
> 4) After more debugging, I observed that, if I apply below change in
> rc-main.c file and create and flash new boot.img in our board and boot it
>
> diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c
> index 3f0f71a..1acdd09 100644
> --- a/drivers/media/rc/rc-main.c
> +++ b/drivers/media/rc/rc-main.c
> @@ -1347,7 +1349,6 @@ int rc_register_device(struct rc_dev *dev)
> return -EINVAL;
>
> set_bit(EV_KEY, dev->input_dev->evbit);
> - set_bit(EV_REP, dev->input_dev->evbit);
> set_bit(EV_MSC, dev->input_dev->evbit);
> set_bit(MSC_SCAN, dev->input_dev->mscbit);
> if (dev->open)
>
> then, after connecting HDMI, I could see remote working over android .
>
>
> So, my query is, does EV_REP in rc-main.c causing remote decoder function to
> fail. Is it some kind of bug. Or am i missing something.
This just tells the input layer to handle autorepeat and is entirely
unrelated; if the rc driver is not reporting pulse/space information
correctly then the input layer never gets any key presses anyway.
I would suspect that the connecting hdmi somehow does a few tricks with
your gpio ports or there is a heisenbug.
Sean
