[PATCH] opp: Allow opp-level to be set to 0

[Viresh Kumar]

The DT bindings don't put such a constraint, nor should the kernel. It
is perfectly fine for opp-level to be set to 0, if we need to put the
performance state votes for a domain for a particular OPP.

Reported-by: Stephan Gerhold <step...@gerhold.net>
Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
---
 drivers/opp/core.c |  3 ---
 drivers/opp/of.c   | 20 +++++++-------------
 2 files changed, 7 insertions(+), 16 deletions(-)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 214c1619b445..2483e765318a 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -2117,9 +2117,6 @@ int dev_pm_opp_xlate_performance_state(struct opp_table 
*src_table,
        int dest_pstate = -EINVAL;
        int i;
 
-       if (!pstate)
-               return 0;
-
        /*
         * Normally the src_table will have the "required_opps" property set to
         * point to one of the OPPs in the dst_table, but in some cases the
diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index e72753be7dc7..87f839a1899a 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -842,7 +842,7 @@ static struct dev_pm_opp *_opp_add_static_v2(struct 
opp_table *opp_table,
 static int _of_add_opp_table_v2(struct device *dev, struct opp_table 
*opp_table)
 {
        struct device_node *np;
-       int ret, count = 0, pstate_count = 0;
+       int ret, count = 0;
        struct dev_pm_opp *opp;
 
        /* OPP table is already initialized for the device */
@@ -876,20 +876,14 @@ static int _of_add_opp_table_v2(struct device *dev, 
struct opp_table *opp_table)
                goto remove_static_opp;
        }
 
-       list_for_each_entry(opp, &opp_table->opp_list, node)
-               pstate_count += !!opp->pstate;
-
-       /* Either all or none of the nodes shall have performance state set */
-       if (pstate_count && pstate_count != count) {
-               dev_err(dev, "Not all nodes have performance state set (%d: 
%d)\n",
-                       count, pstate_count);
-               ret = -ENOENT;
-               goto remove_static_opp;
+       list_for_each_entry(opp, &opp_table->opp_list, node) {
+               /* Any non-zero performance state would enable the feature */
+               if (opp->pstate) {
+                       opp_table->genpd_performance_state = true;
+                       break;
+               }
        }
 
-       if (pstate_count)
-               opp_table->genpd_performance_state = true;
-
        return 0;
 
 remove_static_opp:
-- 
2.25.0.rc1.19.g042ed3e048af