Kevin Hilman <khilman@xxxxxxxxxxxx> writes: > Saravana Kannan <saravanak@xxxxxxxxxx> writes: > >> On Mon, Jan 31, 2022 at 7:18 PM Kevin Hilman <khilman@xxxxxxxxxxxx> wrote: >>> >>> Hi Saravana, >>> >>> Saravana Kannan <saravanak@xxxxxxxxxx> writes: >>> >>> > fw_devlink could end up creating device links for bus only devices. >>> > However, bus only devices don't get probed and can block probe() or >>> > sync_state() [1] call backs of other devices. To avoid this, probe these >>> > devices using the simple-pm-bus driver. >>> > >>> > However, there are instances of devices that are not simple buses (they get >>> > probed by their specific drivers) that also list the "simple-bus" (or other >>> > bus only compatible strings) in their compatible property to automatically >>> > populate their child devices. We still want these devices to get probed by >>> > their specific drivers. So, we make sure this driver only probes devices >>> > that are only buses. >>> > >>> > [1] - https://lore.kernel.org/lkml/CAPDyKFo9Bxremkb1dDrr4OcXSpE0keVze94Cm=zrkOVxHHxBmQ@xxxxxxxxxxxxxx/ >>> > Fixes: c442a0d18744 ("driver core: Set fw_devlink to "permissive" behavior by default") >>> > Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx> >>> > Tested-by: Saravana Kannan <saravanak@xxxxxxxxxx> >>> > Tested-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> >>> >>> This patch landed in stable/linux-5.10.y as commit d5f13bbb5104 and it >>> broke suspend/resume on at least one TI AM335x board I'm testing on: >>> upstream dts: arch/arm/boot/dts/am335x-icev2.dts, upstream defconfig: >>> arch/arm/configs/omap2plus_defconfig. >>> >>> Bisecting between vanilla v5.10 (good) and stable/linux-5.10.y (bad) >>> pointed me to this patch, and I confirmed that reverting just this patch >>> on top of stable/linux-5.10.y makes it work again. >>> >>> Also interesting, this same platform works fine on vanilla v5.15, which >>> also includes this patch. That suggests that either 1) this patch >>> should not have been backported to v5.10 stable or 2) there are some >>> other dependencies that are missing in v5.10. >>> >>> Since vanilla v5.10 works fine, I'm leaning towards (1), but if you have >>> any ideas for deps that need backporting, I'm happy to try. >> >> Oh wow! I didn't realize I made so many changes AFTER 5.10! Unless I'm >> doing something wrong with my git commands. >> $ git log v5.10..v5.15 --oneline -- drivers/of/property.c >> $ git log v5.10..v5.15 --oneline --author=saravanak -- drivers/base/ >> >> If you don't think I got my git command completely wrong, yeah, way >> too many patches are missing on 5.10. I'd go with the option of >> dropping this patch on 5.10. > > I agree. Could you submit a revert for v5.10 stable? As the patch > author, it's probably better if it comes from you. Nevermind, I'm impatient and submitted a revert to stable[1] :) Kevin [1] https://lore.kernel.org/stable/20220202195705.3598798-1-khilman@xxxxxxxxxxxx/
