[PATCH v2 29/48] soc/tegra: pmc: Link domains to the parent Core domain

[Dmitry Osipenko <digetx@xxxxxxxxx>]

The Core domain is a parent of PMC power domains, hence PMC domains
should be set up as a sub-domains of the parent (Core) domain if
"power-domains" phandle presents in a device-tree node of PMC domain.

This allows to propagate GENPD performance changes to the parent Core
domain if performance change is applied to PMC domain.

Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
 drivers/soc/tegra/pmc.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
index 4f96dc7745c4..1a659d1c06d7 100644
--- a/drivers/soc/tegra/pmc.c
+++ b/drivers/soc/tegra/pmc.c
@@ -1236,6 +1236,7 @@ static int tegra_powergate_add(struct tegra_pmc *pmc, struct device_node *np)
 static int tegra_powergate_init(struct tegra_pmc *pmc,
 				struct device_node *parent)
 {
+	struct of_phandle_args child_args, parent_args;
 	struct device_node *np, *child;
 	int err = 0;
 
@@ -1249,6 +1250,24 @@ static int tegra_powergate_init(struct tegra_pmc *pmc,
 			of_node_put(child);
 			break;
 		}
+
+		if (of_parse_phandle_with_args(child, "power-domains",
+					       "#power-domain-cells",
+					       0, &parent_args))
+			continue;
+
+		child_args.np = child;
+		child_args.args_count = 0;
+
+		err = of_genpd_add_subdomain(&parent_args, &child_args);
+		of_node_put(parent_args.np);
+		if (err) {
+			if (err == -ENOENT)
+				err = -EPROBE_DEFER;
+
+			of_node_put(child);
+			break;
+		}
 	}
 
 	of_node_put(np);
-- 
2.29.2