| Message ID | 20200808043512.106865-1-john.stultz@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [RFC] pinctrl: Rework driver_deferred_probe_check_state() evaluation since default timeout has changed | expand |
On Sat, Aug 8, 2020 at 6:35 AM John Stultz <john.stultz@linaro.org> wrote: > In commit bec6c0ecb243 ("pinctrl: Remove use of > driver_deferred_probe_check_state_continue()"), we removed the > use of driver_deferred_probe_check_state_continue() which > effectively never returned -ETIMED_OUT, with the > driver_deferred_probe_check_state() function that had been > reworked to properly return ETIMED_OUT when the deferred probe > timeout expired. Along with that change, we set the default > timeout to 30 seconds. > > However, since moving the timeout to 30 seconds caused some > issues for some users with optional dt links, we set the > default timeout back to zero - see commit ce68929f07de ("driver > core: Revert default driver_deferred_probe_timeout value to 0") > > This in essence changed the behavior of the pinctrl's usage > of driver_deferred_probe_check_state(), as it now would return > ETIMED_OUT by default. Thierry reported this caused problems with > resume on tegra platforms. > > Thus this patch tweaks the pinctrl logic so that it behaves as > before. If modules are enabled, we'll only return EPROBE_DEFERRED > while we're missing drivers linked in the DT. > > Cc: linux-pm@vger.kernel.org > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Cc: Linus Walleij <linus.walleij@linaro.org> > Cc: Thierry Reding <treding@nvidia.com> > Cc: Mark Brown <broonie@kernel.org> > Cc: Liam Girdwood <lgirdwood@gmail.com> > Cc: Bjorn Andersson <bjorn.andersson@linaro.org> > Cc: Saravana Kannan <saravanak@google.com> > Cc: Todd Kjos <tkjos@google.com> > Cc: Len Brown <len.brown@intel.com> > Cc: Pavel Machek <pavel@ucw.cz> > Cc: Ulf Hansson <ulf.hansson@linaro.org> > Cc: Kevin Hilman <khilman@kernel.org> > Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> > Cc: Rob Herring <robh@kernel.org> > Fixes: bec6c0ecb243 ("pinctrl: Remove use of driver_deferred_probe_check_state_continue()") > Fixes: ce68929f07de ("driver core: Revert default driver_deferred_probe_timeout value to 0") > Reported-by: Thierry Reding <thierry.reding@gmail.com> > Signed-off-by: John Stultz <john.stultz@linaro.org> As noted I applied Thierry's similar patch. Yours, Linus Walleij
diff --git a/drivers/pinctrl/devicetree.c b/drivers/pinctrl/devicetree.c index c6fe7d64c913..09ddf567ccb4 100644 --- a/drivers/pinctrl/devicetree.c +++ b/drivers/pinctrl/devicetree.c @@ -129,9 +129,8 @@ static int dt_to_map_one_config(struct pinctrl *p, if (!np_pctldev || of_node_is_root(np_pctldev)) { of_node_put(np_pctldev); ret = driver_deferred_probe_check_state(p->dev); - /* keep deferring if modules are enabled unless we've timed out */ - if (IS_ENABLED(CONFIG_MODULES) && !allow_default && - (ret == -ENODEV)) + /* keep deferring if modules are enabled */ + if (IS_ENABLED(CONFIG_MODULES) && !allow_default) ret = -EPROBE_DEFER; return ret; }
In commit bec6c0ecb243 ("pinctrl: Remove use of driver_deferred_probe_check_state_continue()"), we removed the use of driver_deferred_probe_check_state_continue() which effectively never returned -ETIMED_OUT, with the driver_deferred_probe_check_state() function that had been reworked to properly return ETIMED_OUT when the deferred probe timeout expired. Along with that change, we set the default timeout to 30 seconds. However, since moving the timeout to 30 seconds caused some issues for some users with optional dt links, we set the default timeout back to zero - see commit ce68929f07de ("driver core: Revert default driver_deferred_probe_timeout value to 0") This in essence changed the behavior of the pinctrl's usage of driver_deferred_probe_check_state(), as it now would return ETIMED_OUT by default. Thierry reported this caused problems with resume on tegra platforms. Thus this patch tweaks the pinctrl logic so that it behaves as before. If modules are enabled, we'll only return EPROBE_DEFERRED while we're missing drivers linked in the DT. Cc: linux-pm@vger.kernel.org Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Thierry Reding <treding@nvidia.com> Cc: Mark Brown <broonie@kernel.org> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Todd Kjos <tkjos@google.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Kevin Hilman <khilman@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Rob Herring <robh@kernel.org> Fixes: bec6c0ecb243 ("pinctrl: Remove use of driver_deferred_probe_check_state_continue()") Fixes: ce68929f07de ("driver core: Revert default driver_deferred_probe_timeout value to 0") Reported-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org> --- drivers/pinctrl/devicetree.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)