[PATCH v3 05/11] soc: renesas: rcar-sysc: Enable Clock Domain for r8a7795 I/O devices

[Geert Uytterhoeven <geert+renesas@glider.be>]

On R-Car H3, some power areas (e.g. A3VP) contain I/O devices, which are
also part of the CPG/MSSR Clock Domain.  Hook up the CPG/MSSR Clock
Domain attach/detach callbacks to enable power management using module
clocks.

This also allows to support the Clock Domain for devices in the
"always-on" power area.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
---
v3:
  - Hook up the CPG/MSSR Clock Domain attach/detach callbacks instead of
    using our own copies,

v2:
  - New.
---
 drivers/soc/renesas/rcar-sysc.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/soc/renesas/rcar-sysc.c b/drivers/soc/renesas/rcar-sysc.c
index 28af0b704fc008d2..2d6fbeb481883be7 100644
--- a/drivers/soc/renesas/rcar-sysc.c
+++ b/drivers/soc/renesas/rcar-sysc.c
@@ -9,6 +9,7 @@
  * for more details.
  */
 
+#include <linux/clk/renesas.h>
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/mm.h>
@@ -251,6 +252,15 @@ static void __init rcar_sysc_pd_setup(struct device_node *np,
 		gov = &pm_domain_always_on_gov;
 	}
 
+#ifdef CONFIG_ARCH_R8A7795
+	if (!(pd->flags & (PD_CPU | PD_SCU))) {
+		/* Enable Clock Domain for I/O devices */
+		genpd->flags = GENPD_FLAG_PM_CLK;
+		genpd->attach_dev = cpg_mssr_attach_dev;
+		genpd->detach_dev = cpg_mssr_detach_dev;
+	}
+#endif
+
 	pm_genpd_init(genpd, gov, false);
 	genpd->dev_ops.active_wakeup = rcar_sysc_active_wakeup;
 	genpd->power_off = rcar_sysc_pd_power_off;
-- 
1.9.1