media: camss: Add regulator_bulk support

Add the ability to enable or disable multiple regulators in bulk with
camss. This is useful for sm8250, sdm845 and it looks like sdm660 where we
have more than one CSI regulator to do at once.

It should just work for standalone existing vdda regulators and parts which
don't have an explicitly defined CSI regulator.

[hverkuil: fix camss-csid.c:163:13: warning: 'ret' may be used uninitialized in this function]
Reported-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/qcom/camss/camss-csid.c

@@ -160,7 +160,7 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 	struct device *dev = camss->dev;
 	struct vfe_device *vfe = &camss->vfe[csid->id];
 	u32 version = camss->version;
-	int ret;
+	int ret = 0;
 
 	if (on) {
 		if (version == CAMSS_8250 || version == CAMSS_845) {
@@ -173,7 +173,8 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 		if (ret < 0)
 			return ret;
 
-		ret = csid->vdda ? regulator_enable(csid->vdda) : 0;
+		ret = regulator_bulk_enable(csid->num_supplies,
+					    csid->supplies);
 		if (ret < 0) {
 			pm_runtime_put_sync(dev);
 			return ret;
@@ -181,16 +182,16 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 
 		ret = csid_set_clock_rates(csid);
 		if (ret < 0) {
-			if (csid->vdda)
-				regulator_disable(csid->vdda);
+			regulator_bulk_disable(csid->num_supplies,
+					       csid->supplies);
 			pm_runtime_put_sync(dev);
 			return ret;
 		}
 
 		ret = camss_enable_clocks(csid->nclocks, csid->clock, dev);
 		if (ret < 0) {
-			if (csid->vdda)
-				regulator_disable(csid->vdda);
+			regulator_bulk_disable(csid->num_supplies,
+					       csid->supplies);
 			pm_runtime_put_sync(dev);
 			return ret;
 		}
@@ -201,8 +202,8 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 		if (ret < 0) {
 			disable_irq(csid->irq);
 			camss_disable_clocks(csid->nclocks, csid->clock);
-			if (csid->vdda)
-				regulator_disable(csid->vdda);
+			regulator_bulk_disable(csid->num_supplies,
+					       csid->supplies);
 			pm_runtime_put_sync(dev);
 			return ret;
 		}
@@ -211,7 +212,8 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 	} else {
 		disable_irq(csid->irq);
 		camss_disable_clocks(csid->nclocks, csid->clock);
-		ret = csid->vdda ? regulator_disable(csid->vdda) : 0;
+		regulator_bulk_disable(csid->num_supplies,
+				       csid->supplies);
 		pm_runtime_put_sync(dev);
 		if (version == CAMSS_8250 || version == CAMSS_845)
 			vfe_put(vfe);
@@ -656,15 +658,28 @@ int msm_csid_subdev_init(struct camss *camss, struct csid_device *csid,
 	}
 
 	/* Regulator */
+	for (i = 0; i < ARRAY_SIZE(res->regulators); i++) {
+		if (res->regulators[i])
+			csid->num_supplies++;
+	}
 
-	csid->vdda = NULL;
-	if (res->regulator[0])
-		csid->vdda = devm_regulator_get(dev, res->regulator[0]);
-	if (IS_ERR(csid->vdda)) {
-		dev_err(dev, "could not get regulator\n");
-		return PTR_ERR(csid->vdda);
+	if (csid->num_supplies) {
+		csid->supplies = devm_kmalloc_array(camss->dev,
+						    csid->num_supplies,
+						    sizeof(csid->supplies),
+						    GFP_KERNEL);
+		if (!csid->supplies)
+			return -ENOMEM;
 	}
 
+	for (i = 0; i < csid->num_supplies; i++)
+		csid->supplies[i].supply = res->regulators[i];
+
+	ret = devm_regulator_bulk_get(camss->dev, csid->num_supplies,
+				      csid->supplies);
+	if (ret)
+		return ret;
+
 	init_completion(&csid->reset_complete);
 
 	return 0;

drivers/media/platform/qcom/camss/camss-csid.h

@@ -152,7 +152,8 @@ struct csid_device {
 	char irq_name[30];
 	struct camss_clock *clock;
 	int nclocks;
-	struct regulator *vdda;
+	struct regulator_bulk_data *supplies;
+	int num_supplies;
 	struct completion reset_complete;
 	struct csid_testgen_config testgen;
 	struct csid_phy_config phy;

drivers/media/platform/qcom/camss/camss.h

@@ -42,7 +42,7 @@
 #define CAMSS_RES_MAX 17
 
 struct resources {
-	char *regulator[CAMSS_RES_MAX];
+	char *regulators[CAMSS_RES_MAX];
 	char *clock[CAMSS_RES_MAX];
 	u32 clock_rate[CAMSS_RES_MAX][CAMSS_RES_MAX];
 	char *reg[CAMSS_RES_MAX];