4 files changed, 43 insertions, 14 deletions

diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt
index 3381b9618b5b..adae82385dd6 100644
--- a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt
+++ b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt
@@ -90,8 +90,9 @@ i.mx specific properties
 - fsl,usbmisc: phandler of non-core register device, with one
   argument that indicate usb controller index
 - disable-over-current: disable over current detect
-- over-current-active-high: over current signal polarity is high active,
-  typically over current signal polarity is low active.
+- over-current-active-low: over current signal polarity is active low.
+- over-current-active-high: over current signal polarity is active high.
+  It's recommended to specify the over current polarity.
 - external-vbus-divider: enables off-chip resistor divider for Vbus
 
 Example:
diff --git a/drivers/usb/chipidea/ci_hdrc_imx.c b/drivers/usb/chipidea/ci_hdrc_imx.c
index 56781c329db0..1951b37aa39d 100644
--- a/drivers/usb/chipidea/ci_hdrc_imx.c
+++ b/drivers/usb/chipidea/ci_hdrc_imx.c
@@ -136,11 +136,19 @@ static struct imx_usbmisc_data *usbmisc_get_init_data(struct device *dev)
 
 	data->dev = &misc_pdev->dev;
 
-	if (of_find_property(np, "disable-over-current", NULL))
+	/*
+	 * Check the various over current related properties. If over current
+	 * detection is disabled we're not interested in the polarity.
+	 */
+	if (of_find_property(np, "disable-over-current", NULL)) {
 		data->disable_oc = 1;
-
-	if (of_find_property(np, "over-current-active-high", NULL))
-		data->oc_polarity = 1;
+	} else if (of_find_property(np, "over-current-active-high", NULL)) {
+		data->oc_pol_active_low = 0;
+		data->oc_pol_configured = 1;
+	} else if (of_find_property(np, "over-current-active-low", NULL)) {
+		data->oc_pol_active_low = 1;
+		data->oc_pol_configured = 1;
+	}
 
 	if (of_find_property(np, "external-vbus-divider", NULL))
 		data->evdo = 1;
diff --git a/drivers/usb/chipidea/ci_hdrc_imx.h b/drivers/usb/chipidea/ci_hdrc_imx.h
index fcecab478934..7cc53e2ce564 100644
--- a/drivers/usb/chipidea/ci_hdrc_imx.h
+++ b/drivers/usb/chipidea/ci_hdrc_imx.h
@@ -11,7 +11,13 @@ struct imx_usbmisc_data {
 	int index;
 
 	unsigned int disable_oc:1; /* over current detect disabled */
-	unsigned int oc_polarity:1; /* over current polarity if oc enabled */
+
+	/* true if over-current polarity is active low */
+	unsigned int oc_pol_active_low:1;
+
+	/* true if dt specifies polarity */
+	unsigned int oc_pol_configured:1;
+
 	unsigned int evdo:1; /* set external vbus divider option */
 	unsigned int ulpi:1; /* connected to an ULPI phy */
 	unsigned int hsic:1; /* HSIC controlller */
diff --git a/drivers/usb/chipidea/usbmisc_imx.c b/drivers/usb/chipidea/usbmisc_imx.c
index 43a15a6e86f5..4c3839d345cd 100644
--- a/drivers/usb/chipidea/usbmisc_imx.c
+++ b/drivers/usb/chipidea/usbmisc_imx.c
@@ -356,11 +356,17 @@ static int usbmisc_imx6q_init(struct imx_usbmisc_data *data)
 	reg = readl(usbmisc->base + data->index * 4);
 	if (data->disable_oc) {
 		reg |= MX6_BM_OVER_CUR_DIS;
-	} else if (data->oc_polarity == 1) {
-		/* High active */
-		reg &= ~(MX6_BM_OVER_CUR_DIS | MX6_BM_OVER_CUR_POLARITY);
 	} else {
-		reg &= ~(MX6_BM_OVER_CUR_DIS);
+		reg &= ~MX6_BM_OVER_CUR_DIS;
+
+		/*
+		 * If the polarity is not configured keep it as setup by the
+		 * bootloader.
+		 */
+		if (data->oc_pol_configured && data->oc_pol_active_low)
+			reg |= MX6_BM_OVER_CUR_POLARITY;
+		else if (data->oc_pol_configured)
+			reg &= ~MX6_BM_OVER_CUR_POLARITY;
 	}
 	writel(reg, usbmisc->base + data->index * 4);
 
@@ -552,9 +558,17 @@ static int usbmisc_imx7d_init(struct imx_usbmisc_data *data)
 	reg = readl(usbmisc->base);
 	if (data->disable_oc) {
 		reg |= MX6_BM_OVER_CUR_DIS;
-	} else if (data->oc_polarity == 1) {
-		/* High active */
-		reg &= ~(MX6_BM_OVER_CUR_DIS | MX6_BM_OVER_CUR_POLARITY);
+	} else {
+		reg &= ~MX6_BM_OVER_CUR_DIS;
+
+		/*
+		 * If the polarity is not configured keep it as setup by the
+		 * bootloader.
+		 */
+		if (data->oc_pol_configured && data->oc_pol_active_low)
+			reg |= MX6_BM_OVER_CUR_POLARITY;
+		else if (data->oc_pol_configured)
+			reg &= ~MX6_BM_OVER_CUR_POLARITY;
 	}
 	writel(reg, usbmisc->base);