[PATCH v6 10/10] pmdomain: samsung: implement domain-supply regulator

["André Draszik" <andre.draszik@linaro.org>]

Some power domains on Exynos are fed by a regulator rail and therefore
regulator control needs be implemented for Exynos power domains.

On Google gs101, HSI0 (USB) is one example of such a power domain.

While at it, add a to_exynos_pd() to avoid direct use of
container_of() in various additional places, and update existing code
to use it.

Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
 drivers/pmdomain/samsung/exynos-pm-domains.c | 53 +++++++++++++++++++++++++---
 1 file changed, 48 insertions(+), 5 deletions(-)

diff --git a/drivers/pmdomain/samsung/exynos-pm-domains.c b/drivers/pmdomain/samsung/exynos-pm-domains.c
index f59986b56213..ed7a5807555b 100644
--- a/drivers/pmdomain/samsung/exynos-pm-domains.c
+++ b/drivers/pmdomain/samsung/exynos-pm-domains.c
@@ -20,12 +20,15 @@
 #include <linux/of_address.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
 
 #define EXYNOS_SMC_CMD_PREPARE_PD_ONOFF		0x82000410
 #define EXYNOS_GET_IN_PD_DOWN			0
 #define EXYNOS_WAKEUP_PD_DOWN			1
 #define EXYNOS_RUNTIME_PM_TZPC_GROUP		2
 
+#define to_exynos_pd(gpd) container_of_const(gpd, struct exynos_pm_domain, pd)
+
 struct exynos_pm_domain_config {
 	/* Value for LOCAL_PWR_CFG and STATUS fields for each domain */
 	u32 local_pwr_cfg;
@@ -39,6 +42,7 @@ struct exynos_pm_domain_config {
 struct exynos_pm_domain {
 	struct regmap *regmap;
 	struct device *dev;
+	struct regulator *supply;
 	struct generic_pm_domain pd;
 	const struct exynos_pm_domain_config *cfg;
 	u32 configuration_reg;
@@ -64,12 +68,10 @@ static int exynos_pd_access_controller_power(struct exynos_pm_domain *pd,
 
 static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 {
-	struct exynos_pm_domain *pd;
+	struct exynos_pm_domain *pd = to_exynos_pd(domain);
 	u32 timeout, pwr;
 	int err;
 
-	pd = container_of(domain, struct exynos_pm_domain, pd);
-
 	if (!power_on) {
 		err = exynos_pd_access_controller_power(pd, power_on);
 		if (err) {
@@ -126,14 +128,45 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
 	return err;
 }
 
+static int exynos_pd_regulator_enable(struct regulator *supply)
+{
+	return supply ? regulator_enable(supply) : 0;
+}
+
+static int exynos_pd_regulator_disable(struct regulator *supply)
+{
+	return supply ? regulator_disable(supply) : 0;
+}
+
 static int exynos_pd_power_on(struct generic_pm_domain *domain)
 {
-	return exynos_pd_power(domain, true);
+	struct exynos_pm_domain *pd = to_exynos_pd(domain);
+	int ret;
+
+	ret = exynos_pd_regulator_enable(pd->supply);
+	if (ret)
+		return ret;
+
+	ret = exynos_pd_power(domain, true);
+	if (ret)
+		exynos_pd_regulator_disable(pd->supply);
+
+	return ret;
 }
 
 static int exynos_pd_power_off(struct generic_pm_domain *domain)
 {
-	return exynos_pd_power(domain, false);
+	struct exynos_pm_domain *pd = to_exynos_pd(domain);
+	int ret;
+
+	ret = exynos_pd_power(domain, false);
+	if (ret)
+		return ret;
+
+	/* Ignore regulator errors - the domain was disabled after all. */
+	exynos_pd_regulator_disable(pd->supply);
+
+	return 0;
 }
 
 static const struct exynos_pm_domain_config exynos4210_cfg = {
@@ -283,6 +316,16 @@ static int exynos_pd_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	/* get the domain power supply if required */
+	pd->supply = devm_regulator_get_optional(dev, "domain");
+	if (IS_ERR(pd->supply)) {
+		if (PTR_ERR(pd->supply) != -ENODEV)
+			return dev_err_probe(dev, PTR_ERR(pd->supply),
+					     "failed to get domain supply");
+
+		pd->supply = NULL;
+	}
+
 	/*
 	 * Some Samsung platforms with bootloaders turning on the splash-screen
 	 * and handing it over to the kernel, requires the power-domains to be

-- 
2.53.0.473.g4a7958ca14-goog