[PATCH] usb: chipidea: imx: Allow OC polarity active low

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The implementation for setting the over current polarity has always been
the over-current-active-high property.  The problem with this is there
is no way to enable over current active low polarity since the default
state of the register bit that controls the over current polarity is a 0
which means active high.  This value never actually did anything since
active high is already the default state. Also it is not used in any
device tree source in the kernel.  The default register bit state was
verified by checking the i.MX6Q and i.MX7Dual reference manuals.

The change replaces the over-current-active-high property with the
over-current-active-low property.  Without this property the over
current polarity will be active high by default like it always has been.
With the property the over current polarity will be active low.

Signed-off-by: Matthew Starr <mstarr@xxxxxxxxxxxxx>
---
 Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt |  4 ++--
 drivers/usb/chipidea/ci_hdrc_imx.c                     |  2 +-
 drivers/usb/chipidea/usbmisc_imx.c                     | 10 ++++++----
 3 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt
index 529e51879fb2..3dee58037839 100644
--- a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt
+++ b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt
@@ -87,8 +87,8 @@ 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 low active,
+  the default signal polarity is high active.
 - 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 09b37c0d075d..f7069544fb42 100644
--- a/drivers/usb/chipidea/ci_hdrc_imx.c
+++ b/drivers/usb/chipidea/ci_hdrc_imx.c
@@ -135,7 +135,7 @@ static struct imx_usbmisc_data *usbmisc_get_init_data(struct device *dev)
 	if (of_find_property(np, "disable-over-current", NULL))
 		data->disable_oc = 1;
 
-	if (of_find_property(np, "over-current-active-high", NULL))
+	if (of_find_property(np, "over-current-active-low", NULL))
 		data->oc_polarity = 1;
 
 	if (of_find_property(np, "external-vbus-divider", NULL))
diff --git a/drivers/usb/chipidea/usbmisc_imx.c b/drivers/usb/chipidea/usbmisc_imx.c
index def80ff547e4..39223708e859 100644
--- a/drivers/usb/chipidea/usbmisc_imx.c
+++ b/drivers/usb/chipidea/usbmisc_imx.c
@@ -341,8 +341,9 @@ static int usbmisc_imx6q_init(struct imx_usbmisc_data *data)
 	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);
+		/* Low active */
+		reg &= ~(MX6_BM_OVER_CUR_DIS);
+		reg |= MX6_BM_OVER_CUR_POLARITY;
 	} else {
 		reg &= ~(MX6_BM_OVER_CUR_DIS);
 	}
@@ -445,8 +446,9 @@ static int usbmisc_imx7d_init(struct imx_usbmisc_data *data)
 	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);
+		/* Low active */
+		reg &= ~(MX6_BM_OVER_CUR_DIS);
+		reg |= MX6_BM_OVER_CUR_POLARITY;
 	}
 	writel(reg, usbmisc->base);
 
-- 
2.17.1



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