[PATCH AUTOSEL 4.19 073/237] PM / Domains: Deal with multiple states but no governor in genpd

Sasha Levin
2019-11-16T16:24:05Z

From: Ulf Hansson <ulf.hansson@linaro.org>

[ Upstream commit 2c9b7f8772033cc8bafbd4eefe2ca605bf3eb094 ]

A caller of pm_genpd_init() that provides some states for the genpd via the
->states pointer in the struct generic_pm_domain, should also provide a
governor. This because it's the job of the governor to pick a state that
satisfies the constraints.

Therefore, let's print a warning to inform the user about such bogus
configuration and avoid to bail out, by instead picking the shallowest
state before genpd invokes the ->power_off() callback.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Lina Iyer <ilina@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/base/power/domain.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index bf5be0bfaf773..52c292d0908a2 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -467,6 +467,10 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
return -EAGAIN;
}

+ /* Default to shallowest state. */
+ if (!genpd->gov)
+ genpd->state_idx = 0;
+
if (genpd->power_off) {
int ret;

@@ -1686,6 +1690,8 @@ int pm_genpd_init(struct generic_pm_domain *genpd,
ret = genpd_set_default_power_state(genpd);
if (ret)
return ret;
+ } else if (!gov) {
+ pr_warn("%s : no governor for states\n", genpd->name);
}

device_initialize(&genpd->dev);
--
2.20.1