usb: chipidea: imx: set power polarity

This patch adds support to set the power line polarity for i.MX SoCs.

To let the USB controller control the power it may be necessary to
configure the polarity of the power line. So far the polarity was
configured by Bootloader or alternatively the power line was muxed
as gpio and driven by a regulator.

Also make use of of_property_read_bool.
Signed-off-by: Philipp Puschmann <philipp.puschmann@emlix.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/chipidea/ci_hdrc_imx.c

@@ -150,8 +150,8 @@ static struct imx_usbmisc_data *usbmisc_get_init_data(struct device *dev)
 		dev_warn(dev, "No over current polarity defined\n");
 	}
 
-	if (of_find_property(np, "external-vbus-divider", NULL))
-		data->evdo = 1;
+	data->pwr_pol = of_property_read_bool(np, "power-active-high");
+	data->evdo = of_property_read_bool(np, "external-vbus-divider");
 
 	if (of_usb_get_phy_mode(np) == USBPHY_INTERFACE_MODE_ULPI)
 		data->ulpi = 1;

drivers/usb/chipidea/ci_hdrc_imx.h

@@ -18,6 +18,7 @@ struct imx_usbmisc_data {
 	/* true if dt specifies polarity */
 	unsigned int oc_pol_configured:1;
 
+	unsigned int pwr_pol:1; /* power polarity */
 	unsigned int evdo:1; /* set external vbus divider option */
 	unsigned int ulpi:1; /* connected to an ULPI phy */
 	unsigned int hsic:1; /* HSIC controlller */

drivers/usb/chipidea/usbmisc_imx.c

@@ -63,6 +63,7 @@
 #define MX6_BM_NON_BURST_SETTING	BIT(1)
 #define MX6_BM_OVER_CUR_DIS		BIT(7)
 #define MX6_BM_OVER_CUR_POLARITY	BIT(8)
+#define MX6_BM_PWR_POLARITY		BIT(9)
 #define MX6_BM_WAKEUP_ENABLE		BIT(10)
 #define MX6_BM_UTMI_ON_CLOCK		BIT(13)
 #define MX6_BM_ID_WAKEUP		BIT(16)
@@ -383,6 +384,9 @@ static int usbmisc_imx6q_init(struct imx_usbmisc_data *data)
 		else if (data->oc_pol_configured)
 			reg &= ~MX6_BM_OVER_CUR_POLARITY;
 	}
+	/* If the polarity is not set keep it as setup by the bootlader */
+	if (data->pwr_pol == 1)
+		reg |= MX6_BM_PWR_POLARITY;
 	writel(reg, usbmisc->base + data->index * 4);
 
 	/* SoC non-burst setting */
@@ -585,6 +589,9 @@ static int usbmisc_imx7d_init(struct imx_usbmisc_data *data)
 		else if (data->oc_pol_configured)
 			reg &= ~MX6_BM_OVER_CUR_POLARITY;
 	}
+	/* If the polarity is not set keep it as setup by the bootlader */
+	if (data->pwr_pol == 1)
+		reg |= MX6_BM_PWR_POLARITY;
 	writel(reg, usbmisc->base);
 
 	reg = readl(usbmisc->base + MX7D_USBNC_USB_CTRL2);