From: Rajendra Nayak rnayak@codeaurora.org

commit a4501bac0e553bed117b7e1b166d49731caf7260 upstream.

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 [ Viresh: Updated the patch to apply to v5.4 ] Signed-off-by: Viresh Kumar viresh.kumar@linaro.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 9ff0538ee83a..518442be638d 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -843,10 +843,12 @@ 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) { + dev_dbg(dev, "%s: old/new frequencies (%lu Hz) are same, nothing to do\n", + __func__, freq); + ret = 0; + goto put_opp_table; + } }

temp_freq = old_freq;