[PATCH v1 3/8] PM / devfreq: tegra: Don't ignore clk errors

From: Dmitry Osipenko
Date: Thu Apr 11 2019 - 18:30:09 EST


The clk_set_min_rate() could fail and in this case clk_set_rate() sets
rate to 0, which may drop EMC rate to minimum and make machine very
difficult to use.

Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
drivers/devfreq/tegra-devfreq.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/devfreq/tegra-devfreq.c b/drivers/devfreq/tegra-devfreq.c
index d749399f67ae..6185e7ab20a8 100644
--- a/drivers/devfreq/tegra-devfreq.c
+++ b/drivers/devfreq/tegra-devfreq.c
@@ -487,6 +487,7 @@ static int tegra_devfreq_target(struct device *dev, unsigned long *freq,
struct tegra_devfreq *tegra = dev_get_drvdata(dev);
struct dev_pm_opp *opp;
unsigned long rate;
+ int err;

opp = devfreq_recommended_opp(dev, freq, flags);
if (IS_ERR(opp)) {
@@ -496,8 +497,13 @@ static int tegra_devfreq_target(struct device *dev, unsigned long *freq,
rate = dev_pm_opp_get_freq(opp) * KHZ;
dev_pm_opp_put(opp);

- clk_set_min_rate(tegra->emc_clock, rate);
- clk_set_rate(tegra->emc_clock, 0);
+ err = clk_set_min_rate(tegra->emc_clock, rate);
+ if (err)
+ return err;
+
+ err = clk_set_rate(tegra->emc_clock, 0);
+ if (err)
+ return err;

return 0;
}
--
2.21.0