On Sun, Jan 16, 2022 at 05:08:29PM +0100, Luca Weiss wrote: > On Mittwoch, 12. Jänner 2022 22:39:53 CET Stephan Gerhold wrote: > > On Wed, Jan 12, 2022 at 08:40:58PM +0100, Luca Weiss wrote: > > > From: Vladimir Lypak <vladimir.lypak@xxxxxxxxx> > > > > > > RPM Firmware on variety of newer SoCs such as MSM8917 (also likely > > > MSM8937, MSM8940, MSM8952), MSM8953 and on some MSM8916 devices) doesn't > > > initiate opening of the SMD channel if it was previously opened by > > > bootloader. This doesn't allow probing of smd-rpm driver on such devices > > > because there is a check that requires RPM this behaviour. > > > > > > Signed-off-by: Vladimir Lypak <vladimir.lypak@xxxxxxxxx> > > > Signed-off-by: Luca Weiss <luca@xxxxxxxxx> > > > Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxx> > > > > This is effectively a "Revert "Revert "rpmsg: smd: Create device for all > > channels""": > > > > https://lore.kernel.org/linux-arm-msm/20171212235857.10432-3-bjorn.andersson > > @linaro.org/ > > https://lore.kernel.org/linux-arm-msm/20180315181244.8859-1-bjorn.andersson > > @linaro.org/ > > > > Won't this cause the same regression reported by Srinivas again? > > > > Do you have any suggestion on another way to solve this? Without this commit > the regulators just won't probe at all, I haven't looked very deep into it > though given this patch solves it. > > I guess worst case it'll become a devicetree property to enable this quirk? > My spontaneous suggestion would be to skip the check only for the "rpm_requests" channel, e.g. something like if (remote_state != SMD_CHANNEL_OPENING && remote_state != SMD_CHANNEL_OPENED && strcmp(channel->name, "rpm_requests") continue; This will avoid changing the behavior for anything but the RPM channel. I don't think anything else is affected by the same problem (since the bootloader or earlier firmware should not make use of any other channel). Also, we definitely *always* want to open the channel to the RPM because otherwise almost everything breaks. Many solutions are possible though so at the end it is mostly up to Bjorn to decide I think. :) Thanks, Stephan
