[PATCH 5.7 032/124] opp: Enable resources again if they were disabled earlier

Greg Kroah-Hartman
2020-08-24T09:46:48Z

From: Rajendra Nayak <rnayak@codeaurora.org>

[ Upstream commit a4501bac0e553bed117b7e1b166d49731caf7260 ]

dev_pm_opp_set_rate() can now be called with freq = 0 in order
to either drop performance or bandwidth votes or to disable
regulators on platforms which support them.

In such cases, a subsequent call to dev_pm_opp_set_rate() with
the same frequency ends up returning early because 'old_freq == freq'

Instead make it fall through and put back the dropped performance
and bandwidth votes and/or enable back the regulators.

Cc: v5.3+ <stable@vger.kernel.org> # v5.3+
Fixes: cd7ea582866f ("opp: Make dev_pm_opp_set_rate() handle freq = 0 to drop performance votes")
Reported-by: Sajida Bhanu <sbhanu@codeaurora.org>
Reviewed-by: Sibi Sankar <sibis@codeaurora.org>
Reported-by: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
[ Viresh: Don't skip clk_set_rate() and massaged changelog ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/opp/core.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index e4f01e7771a22..195fcaff18448 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -845,10 +845,12 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)

/* Return early if nothing to do */
if (old_freq == freq) {
- dev_dbg(dev, "%s: old/new frequencies (%lu Hz) are same, nothing to do\n",
- __func__, freq);
- ret = 0;
- goto put_opp_table;
+ if (!opp_table->required_opp_tables && !opp_table->regulators) {
+ dev_dbg(dev, "%s: old/new frequencies (%lu Hz) are same, nothing to do\n",
+ __func__, freq);
+ ret = 0;
+ goto put_opp_table;
+ }
}

/*
--
2.25.1