> Wiadomość napisana przez Robin Murphy <robin.murphy@xxxxxxx> w dniu 11.07.2022, o godz. 12:41: > > On 2022-06-25 16:31, Piotr Oniszczuk wrote: >>> Wiadomość napisana przez Peter Geis <pgwipeout@xxxxxxxxx> w dniu 25.06.2022, o godz. 16:00: >>> >>> >>> The first issue you have is the TV isn't responding until the absolute >>> end. >> I suspect this is because lack on idle gaps between cec commands sent from board to tv. >> Maybe TV sw. can't deal with consecutive commands without any idle between them? >> It is interesting that disconnecting TV - so CEC line is driven only by board - rock3a still don't have any idle gaps while rock3b (and radxa 4.19 bsp) has them (very similar between 5.18mailine and 4.19 bsp). >> How this is possible that change I/O from m0->m1 impacts _timings_ on free hanging CEC line? > > Check all the pinctrl settings beyond just the function mux - pulls, drive strength, output type, etc. - the defaults tend to be all over the place, and rarely what you want. > > Robin. Robin, I'm not sure do I looked in right place... but: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/arch/arm64/boot/dts/rockchip/rk3568-pinctrl.dtsi?h=v5.18.10#n788 vs. https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/arch/arm64/boot/dts/rockchip/rk3568-pinctrl.dtsi?h=v5.18.10#n795 are looking ok? > >>> This strikes me as a signal integrity issue. Do you have an >>> oscilloscope (not a logic analyzer, you need voltages and ramp times) >>> to compare the working vs non-working signals? Check both sides of the >>> level shifter. >> Indeed - i will verify this with digital oscilloscope. >> Already ordered and must await week or 2 for delivery :-( >> My analog oscilloscope shows correct levels and slopes "seems" to be the same like in working (no memory so i can compare only visually on fuzzy screen) >> For me key is to understand why on rock3a there is no any idles between cec commands - even when nothing is connected to bard (so cec is only sending and nothing external impacts cec state machine).... >> _______________________________________________ >> Linux-rockchip mailing list >> Linux-rockchip@xxxxxxxxxxxxxxxxxxx >> http://lists.infradead.org/mailman/listinfo/linux-rockchip
