[PATCH v2] cpufreq/amd-pstate: Fix the return value of amd_pstate_fast_switch()

From: Gautham R. Shenoy
Date: Mon Nov 27 2023 - 06:12:01 EST


cpufreq_driver->fast_switch() callback expects a frequency as a return
value. amd_pstate_fast_switch() was returning the return value of
amd_pstate_update_freq(), which only indicates a success or failure.

Fix this by making amd_pstate_fast_switch() return the target_freq
when the call to amd_pstate_update_freq() is successful, and return
the current frequency from policy->cur when the call to
amd_pstate_update_freq() is unsuccessful.

Fixes: 4badf2eb1e98 ("cpufreq: amd-pstate: Add ->fast_switch() callback")
Acked-by: Huang Rui <ray.huang@xxxxxxx>
Reviewed-by: Wyes Karny <wyes.karny@xxxxxxx>
Reviewed-by: Perry Yuan <perry.yuan@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v6.4+
Signed-off-by: Gautham R. Shenoy <gautham.shenoy@xxxxxxx>
---
drivers/cpufreq/amd-pstate.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 9a1e194d5cf8..300f81d36291 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -518,7 +518,9 @@ static int amd_pstate_target(struct cpufreq_policy *policy,
static unsigned int amd_pstate_fast_switch(struct cpufreq_policy *policy,
unsigned int target_freq)
{
- return amd_pstate_update_freq(policy, target_freq, true);
+ if (!amd_pstate_update_freq(policy, target_freq, true))
+ return target_freq;
+ return policy->cur;
}

static void amd_pstate_adjust_perf(unsigned int cpu,
--
2.25.1