[RFC 6/8] usb: phy: qcom: use bulk regulator interfaces

[Arnd Bergmann]

When build-testing the phy-msm-usb driver, we can run into a gcc warning:

drivers/usb/phy/phy-msm-usb.c: In function 'msm_otg_probe':
drivers/usb/phy/phy-msm-usb.c:1735:14: error: 'regs[0].consumer' may be used uninitialized in this function [-Werror=maybe-uninitialized]
drivers/usb/phy/phy-msm-usb.c:1736:14: error: 'regs[1].consumer' may be used uninitialized in this function [-Werror=maybe-uninitialized]
drivers/usb/phy/phy-msm-usb.c:1737:14: error: 'regs[2].consumer' may be used uninitialized in this function [-Werror=maybe-uninitialized]

Like in the phy-qcom-8x16-usb.c driver that was reworked in 7e8ac87a4474
("usb: phy: qcom-8x16: fix regulator API abuse"), this warning goes
away once we consistently use the bulk regulator API, which also
simplifies the driver a bit.

This patch should not change the behavior of the driver, other than
how we now first set the voltage on all regulators and then enable
or disable them, rather than doing it one regulator at a time.
In particular, it looks like a mistake that msm_otg_remove() disables
only two of the three regulators that are enabled in msm_otg_probe(),
but changing that is left for another patch.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
 drivers/usb/phy/phy-msm-usb.c | 155 ++++++++++++++++++------------------------
 1 file changed, 65 insertions(+), 90 deletions(-)

diff --git a/drivers/usb/phy/phy-msm-usb.c b/drivers/usb/phy/phy-msm-usb.c
index ea4ed6c17b00..bdcf049e465f 100644
--- a/drivers/usb/phy/phy-msm-usb.c
+++ b/drivers/usb/phy/phy-msm-usb.c
@@ -260,9 +260,7 @@ struct msm_otg {
 	enum usb_chg_state chg_state;
 	enum usb_chg_type chg_type;
 	u8 dcd_retries;
-	struct regulator *v3p3;
-	struct regulator *v1p8;
-	struct regulator *vddcx;
+	struct regulator_bulk_data regulators[3];
 
 	struct reset_control *phy_rst;
 	struct reset_control *link_rst;
@@ -303,96 +301,69 @@ enum vdd_levels {
 	VDD_LEVEL_MAX,
 };
 
+enum regulators {
+	VDDCX = 0,
+	V3P3  = 1,
+	V1P8  = 2,
+};
+
 static int msm_hsusb_init_vddcx(struct msm_otg *motg, int init)
 {
 	int ret = 0;
+	struct regulator *vddcx = motg->regulators[VDDCX].consumer;
 
-	if (init) {
-		ret = regulator_set_voltage(motg->vddcx,
+	if (init)
+		ret = regulator_set_voltage(vddcx,
 				motg->vdd_levels[VDD_LEVEL_MIN],
 				motg->vdd_levels[VDD_LEVEL_MAX]);
-		if (ret) {
-			dev_err(motg->phy.dev, "Cannot set vddcx voltage\n");
-			return ret;
-		}
-
-		ret = regulator_enable(motg->vddcx);
-		if (ret)
-			dev_err(motg->phy.dev, "unable to enable hsusb vddcx\n");
-	} else {
-		ret = regulator_set_voltage(motg->vddcx, 0,
+	else
+		ret = regulator_set_voltage(vddcx, 0,
 				motg->vdd_levels[VDD_LEVEL_MAX]);
-		if (ret)
-			dev_err(motg->phy.dev, "Cannot set vddcx voltage\n");
-		ret = regulator_disable(motg->vddcx);
-		if (ret)
-			dev_err(motg->phy.dev, "unable to disable hsusb vddcx\n");
-	}
+
+
+	if (ret)
+		dev_err(motg->phy.dev, "Cannot set vddcx voltage\n");
 
 	return ret;
 }
 
-static int msm_hsusb_ldo_init(struct msm_otg *motg, int init)
+static int msm_hsusb_ldo_init(struct msm_otg *motg)
 {
 	int rc = 0;
 
-	if (init) {
-		rc = regulator_set_voltage(motg->v3p3, USB_PHY_3P3_VOL_MIN,
-				USB_PHY_3P3_VOL_MAX);
-		if (rc) {
-			dev_err(motg->phy.dev, "Cannot set v3p3 voltage\n");
-			goto exit;
-		}
-		rc = regulator_enable(motg->v3p3);
-		if (rc) {
-			dev_err(motg->phy.dev, "unable to enable the hsusb 3p3\n");
-			goto exit;
-		}
-		rc = regulator_set_voltage(motg->v1p8, USB_PHY_1P8_VOL_MIN,
-				USB_PHY_1P8_VOL_MAX);
-		if (rc) {
-			dev_err(motg->phy.dev, "Cannot set v1p8 voltage\n");
-			goto disable_3p3;
-		}
-		rc = regulator_enable(motg->v1p8);
-		if (rc) {
-			dev_err(motg->phy.dev, "unable to enable the hsusb 1p8\n");
-			goto disable_3p3;
-		}
-
-		return 0;
+	rc = regulator_set_voltage(motg->regulators[V3P3].consumer,
+			USB_PHY_3P3_VOL_MIN, USB_PHY_3P3_VOL_MAX);
+	if (rc) {
+		dev_err(motg->phy.dev, "Cannot set v3p3 voltage\n");
+		goto exit;
+	}
+	rc = regulator_set_voltage(motg->regulators[V1P8].consumer,
+			USB_PHY_1P8_VOL_MIN, USB_PHY_1P8_VOL_MAX);
+	if (rc) {
+		dev_err(motg->phy.dev, "Cannot set v1p8 voltage\n");
 	}
-
-	regulator_disable(motg->v1p8);
-disable_3p3:
-	regulator_disable(motg->v3p3);
 exit:
 	return rc;
 }
 
 static int msm_hsusb_ldo_set_mode(struct msm_otg *motg, int on)
 {
-	int ret = 0;
+	int ret;
+	int load_v1p8 = on ? USB_PHY_1P8_HPM_LOAD : USB_PHY_1P8_LPM_LOAD;
+	int load_v3p3 = on ? USB_PHY_3P3_HPM_LOAD : USB_PHY_3P3_LPM_LOAD;
+	const char *state = on ? "HPM" : "LPM";
 
-	if (on) {
-		ret = regulator_set_load(motg->v1p8, USB_PHY_1P8_HPM_LOAD);
-		if (ret < 0) {
-			pr_err("Could not set HPM for v1p8\n");
-			return ret;
-		}
-		ret = regulator_set_load(motg->v3p3, USB_PHY_3P3_HPM_LOAD);
-		if (ret < 0) {
-			pr_err("Could not set HPM for v3p3\n");
-			regulator_set_load(motg->v1p8, USB_PHY_1P8_LPM_LOAD);
-			return ret;
-		}
-	} else {
-		ret = regulator_set_load(motg->v1p8, USB_PHY_1P8_LPM_LOAD);
-		if (ret < 0)
-			pr_err("Could not set LPM for v1p8\n");
-		ret = regulator_set_load(motg->v3p3, USB_PHY_3P3_LPM_LOAD);
-		if (ret < 0)
-			pr_err("Could not set LPM for v3p3\n");
+	ret = regulator_set_load(motg->regulators[V1P8].consumer, load_v1p8);
+	if (ret < 0) {
+		pr_err("Could not set %s for v1p8\n", state);
+		return ret;
+	}
+	ret = regulator_set_load(motg->regulators[V3P3].consumer, load_v3p3);
+	if (ret < 0) {
+		pr_err("Could not set %s for v3p3\n", state);
+		regulator_set_load(motg->regulators[V1P8].consumer,
+				   USB_PHY_1P8_LPM_LOAD);
+		return ret;
 	}
 
 	pr_debug("reg (%s)\n", on ? "HPM" : "LPM");
@@ -701,7 +672,8 @@ static int msm_hsusb_config_vddcx(struct msm_otg *motg, int high)
 	else
 		min_vol = motg->vdd_levels[VDD_LEVEL_NONE];
 
-	ret = regulator_set_voltage(motg->vddcx, min_vol, max_vol);
+	ret = regulator_set_voltage(motg->regulators[VDDCX].consumer,
+				    min_vol, max_vol);
 	if (ret) {
 		pr_err("Cannot set vddcx voltage\n");
 		return ret;
@@ -1868,7 +1840,6 @@ static int msm_otg_reboot_notify(struct notifier_block *this,
 
 static int msm_otg_probe(struct platform_device *pdev)
 {
-	struct regulator_bulk_data regs[3];
 	int ret = 0;
 	struct device_node *np = pdev->dev.of_node;
 	struct msm_otg_platform_data *pdata;
@@ -1950,18 +1921,16 @@ static int msm_otg_probe(struct platform_device *pdev)
 		goto unregister_extcon;
 	}
 
-	regs[0].supply = "vddcx";
-	regs[1].supply = "v3p3";
-	regs[2].supply = "v1p8";
+	motg->regulators[VDDCX].supply = "vddcx";
+	motg->regulators[V3P3].supply  = "v3p3";
+	motg->regulators[V1P8].supply  = "v1p8";
 
-	ret = devm_regulator_bulk_get(motg->phy.dev, ARRAY_SIZE(regs), regs);
+	ret = devm_regulator_bulk_get(motg->phy.dev,
+				      ARRAY_SIZE(motg->regulators),
+				      motg->regulators);
 	if (ret)
 		goto unregister_extcon;
 
-	motg->vddcx = regs[0].consumer;
-	motg->v3p3  = regs[1].consumer;
-	motg->v1p8  = regs[2].consumer;
-
 	clk_set_rate(motg->clk, 60000000);
 
 	clk_prepare_enable(motg->clk);
@@ -1976,15 +1945,21 @@ static int msm_otg_probe(struct platform_device *pdev)
 		goto disable_clks;
 	}
 
-	ret = msm_hsusb_ldo_init(motg, 1);
+	ret = msm_hsusb_ldo_init(motg);
 	if (ret) {
 		dev_err(&pdev->dev, "hsusb vreg configuration failed\n");
-		goto disable_vddcx;
+		goto disable_clks;
+	}
+	ret = regulator_bulk_enable(ARRAY_SIZE(motg->regulators), motg->regulators);
+	if (ret)
+		{
+		dev_err(&pdev->dev, "hsusb could not enable regulators\n");
+		goto disable_clks;
 	}
 	ret = msm_hsusb_ldo_set_mode(motg, 1);
 	if (ret) {
 		dev_err(&pdev->dev, "hsusb vreg enable failed\n");
-		goto disable_ldo;
+		goto disable_regulators;
 	}
 
 	writel(0, USB_USBINTR);
@@ -1996,7 +1971,7 @@ static int msm_otg_probe(struct platform_device *pdev)
 					"msm_otg", motg);
 	if (ret) {
 		dev_err(&pdev->dev, "request irq failed\n");
-		goto disable_ldo;
+		goto disable_regulators;
 	}
 
 	phy->init = msm_phy_init;
@@ -2015,7 +1990,7 @@ static int msm_otg_probe(struct platform_device *pdev)
 	ret = usb_add_phy_dev(&motg->phy);
 	if (ret) {
 		dev_err(&pdev->dev, "usb_add_phy failed\n");
-		goto disable_ldo;
+		goto disable_regulators;
 	}
 
 	platform_set_drvdata(pdev, motg);
@@ -2044,10 +2019,9 @@ static int msm_otg_probe(struct platform_device *pdev)
 
 	return 0;
 
-disable_ldo:
-	msm_hsusb_ldo_init(motg, 0);
-disable_vddcx:
+disable_regulators:
 	msm_hsusb_init_vddcx(motg, 0);
+	regulator_bulk_disable(ARRAY_SIZE(motg->regulators), motg->regulators);
 disable_clks:
 	clk_disable_unprepare(motg->pclk);
 	clk_disable_unprepare(motg->clk);
@@ -2114,7 +2088,8 @@ static int msm_otg_remove(struct platform_device *pdev)
 	clk_disable_unprepare(motg->clk);
 	if (!IS_ERR(motg->core_clk))
 		clk_disable_unprepare(motg->core_clk);
-	msm_hsusb_ldo_init(motg, 0);
+	/* vddcx is left active */
+	regulator_bulk_disable(2, &motg->regulators[V3P3]);
 
 	pm_runtime_set_suspended(&pdev->dev);
 
-- 
2.7.0