Re: pi zero w as tramsitter

On Sun, 30 Aug 2020, Sean Young wrote:

> On Sun, Aug 30, 2020 at 04:30:51PM +0200, [email protected] wrote:
>> On Sat, 29 Aug 2020, Sean Young wrote:
>>> On Sat, Aug 29, 2020 at 06:10:28PM +0200, grumpy--- via LIRC-list wrote:
>>>> for a couple of years i have used a pi zero w with a tsal6400 led to control devices
>>>> i've had no problems until recently
>>>> i purchased a no brand name hdmi switcher
>>>> i recorded the remote but the pi zero w refused to control the device
>>>> just as a test i plugged the led into a pi3
>>>> it worked great talk'n to the switcher
>>>> the pi zero w and the pi3 have the same version of raspbian
>>>> they both use the same version of lirc and the same config files
>>>> the led is driven by a transistor that is powered external to the pi's
>>>> has anyone experienced this behavior before
>>>
>>> So it would be useful to know what driver your are using for IR, i.e.
>>> is it lirc_rpi, or gpio-ir-tx? What version of raspbian are you using?
>>>
>>> One explanation is that the gpio-ir-tx driver has flaws which have only
>>> recently been fixed:
>>>
>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/media/rc/gpio-ir-tx.c?id=ea8912b788f8144e7d32ee61e5ccba45424bef83
>>>
>>> The problems fixed by this patch certainly can be affected by a slower CPU.
>>>
>>> It would be good to know if this fixes your problems by compiling your
>>> kernel with this patch.
>>>
>>> Thanks
>>> Sean
>>>
>>
>> BINGO!!!
>
> So does this patch fix your issue?
previously i had the stock kernel from raspbian, 5.4.51
i could not communicate with my hdmi switcher using pi zero
i used the instructions at https://www.raspberrypi.org/documentation/linux/kernel/building.md
i cross compiled kernel 5.4.59 with your patch
now i am able to communicate with my hdmi switcher using the same pi zero

thanks


> If so, I'll ask for it to be included
> in earlier stable kernels.
>
> Thanks
>
> Sean
>