[PATCH 7.1 065/228] pmdomain: arm: Fix -EINVAL from scmi_pd_set_perf_state() on state 0

7.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Praveen Talari <[email protected]>

commit 3314c90a2eda3df7da4ab6f4388e667b2758de7f upstream.

Currently, scmi_pd_set_perf_state() treats a performance state of 0 as
invalid and returns -EINVAL. As a result, devices attached to SCMI
performance domains can report failures when relinquishing their
performance vote.

The OPP framework use performance state 0 to indicate that no performance
vote is required. For example, dev_pm_opp_set_rate(dev, 0) is commonly
used (by firmware or linux)  when a device is runtime suspended.

A zero performance state does not require any SCMI performance request
to be sent. Treat it as a no-op and return success instead of reporting
an error.

Signed-off-by: Praveen Talari <[email protected]>
Fixes: 2af23ceb8624 ("pmdomain: arm: Add the SCMI performance domain")
Cc: [email protected]
Signed-off-by: Ulf Hansson <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 drivers/pmdomain/arm/scmi_perf_domain.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/pmdomain/arm/scmi_perf_domain.c
+++ b/drivers/pmdomain/arm/scmi_perf_domain.c
@@ -33,7 +33,7 @@ scmi_pd_set_perf_state(struct generic_pm
 		return 0;
 
 	if (!state)
-		return -EINVAL;
+		return 0;
 
 	ret = pd->perf_ops->level_set(pd->ph, pd->domain_id, state, false);
 	if (ret)