PM / Domains: Ignore domain-idle-states that are not compatible

domain-idle-states property may have phandles to idle state bindings
that may not be compatible with idle state definition defined in [1].
Such phandles would just be ignored and not throw and error when read by
the domain core.
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Documentation/devicetree/bindings/power/power_domain.txt

@@ -31,7 +31,9 @@ Optional properties:
 
 - domain-idle-states : A phandle of an idle-state that shall be soaked into a
                 generic domain power state. The idle state definitions are
-                compatible with domain-idle-state specified in [1].
+                compatible with domain-idle-state specified in [1]. phandles
+                that are not compatible with domain-idle-state will be
+                ignored.
   The domain-idle-state property reflects the idle state of this PM domain and
   not the idle states of the devices or sub-domains in the PM domain. Devices
   and sub-domains have their own idle-states independent of the parent

drivers/base/power/domain.c

@@ -2093,11 +2093,6 @@ static int genpd_parse_state(struct genpd_power_state *genpd_state,
 	int err;
 	u32 residency;
 	u32 entry_latency, exit_latency;
-	const struct of_device_id *match_id;
-
-	match_id = of_match_node(idle_state_match, state_node);
-	if (!match_id)
-		return -EINVAL;
 
 	err = of_property_read_u32(state_node, "entry-latency-us",
 						&entry_latency);
@@ -2146,6 +2141,7 @@ int of_genpd_parse_idle_states(struct device_node *dn,
 	int err, ret;
 	int count;
 	struct of_phandle_iterator it;
+	const struct of_device_id *match_id;
 
 	count = of_count_phandle_with_args(dn, "domain-idle-states", NULL);
 	if (count <= 0)
@@ -2158,6 +2154,9 @@ int of_genpd_parse_idle_states(struct device_node *dn,
 	/* Loop over the phandles until all the requested entry is found */
 	of_for_each_phandle(&it, err, dn, "domain-idle-states", NULL, 0) {
 		np = it.node;
+		match_id = of_match_node(idle_state_match, np);
+		if (!match_id)
+			continue;
 		ret = genpd_parse_state(&st[i++], np);
 		if (ret) {
 			pr_err
@@ -2169,8 +2168,11 @@ int of_genpd_parse_idle_states(struct device_node *dn,
 		}
 	}
 
-	*n = count;
-	*states = st;
+	*n = i;
+	if (!i)
+		kfree(st);
+	else
+		*states = st;
 
 	return 0;
 }