[RFC PATCH] usb: chipidea: Add support for VBUS control with PHY

[Piyush Mehta]

Some platforms make use of VBUS control over PHY which means controller
driver has to access PHY registers to turn on/off VBUS line.This patch
adds support for such platforms in chipidea.

Flag 'CI_HDRC_PHY_VBUS_CONTROL' added to support VBus control feature.

Signed-off-by: Piyush Mehta <piyush.mehta@xxxxxxxxxx>
---
We have created this patch as RFC, as I introduced a new flag
(CI_HDRC_PHY_VBUS_CONTROL) and would like to get comment if
it's the proper way to check for VBus support for zynq.
---
 drivers/usb/chipidea/ci_hdrc_usb2.c | 1 +
 drivers/usb/chipidea/host.c         | 7 +++++++
 drivers/usb/chipidea/otg_fsm.c      | 7 +++++++
 include/linux/usb/chipidea.h        | 1 +
 4 files changed, 16 insertions(+)

diff --git a/drivers/usb/chipidea/ci_hdrc_usb2.c b/drivers/usb/chipidea/ci_hdrc_usb2.c
index 89e1d82..dc86b12 100644
--- a/drivers/usb/chipidea/ci_hdrc_usb2.c
+++ b/drivers/usb/chipidea/ci_hdrc_usb2.c
@@ -30,6 +30,7 @@ static const struct ci_hdrc_platform_data ci_default_pdata = {
 
 static const struct ci_hdrc_platform_data ci_zynq_pdata = {
 	.capoffset	= DEF_CAPOFFSET,
+	.flags          = CI_HDRC_PHY_VBUS_CONTROL,
 };
 
 static const struct ci_hdrc_platform_data ci_zevio_pdata = {
diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c
index bdc3885..bc3634a 100644
--- a/drivers/usb/chipidea/host.c
+++ b/drivers/usb/chipidea/host.c
@@ -63,6 +63,13 @@ static int ehci_ci_portpower(struct usb_hcd *hcd, int portnum, bool enable)
 		priv->enabled = enable;
 	}
 
+	if (ci->platdata->flags & CI_HDRC_PHY_VBUS_CONTROL) {
+		if (enable)
+			usb_phy_vbus_on(ci->usb_phy);
+		else
+			usb_phy_vbus_off(ci->usb_phy);
+	}
+
 	if (enable && (ci->platdata->phy_mode == USBPHY_INTERFACE_MODE_HSIC)) {
 		/*
 		 * Marvell 28nm HSIC PHY requires forcing the port to HS mode.
diff --git a/drivers/usb/chipidea/otg_fsm.c b/drivers/usb/chipidea/otg_fsm.c
index 6ed4b00..5ed9164 100644
--- a/drivers/usb/chipidea/otg_fsm.c
+++ b/drivers/usb/chipidea/otg_fsm.c
@@ -471,6 +471,10 @@ static void ci_otg_drv_vbus(struct otg_fsm *fsm, int on)
 				return;
 			}
 		}
+
+		if (ci->platdata->flags & CI_HDRC_PHY_VBUS_CONTROL)
+			usb_phy_vbus_on(ci->usb_phy);
+
 		/* Disable data pulse irq */
 		hw_write_otgsc(ci, OTGSC_DPIE, 0);
 
@@ -480,6 +484,9 @@ static void ci_otg_drv_vbus(struct otg_fsm *fsm, int on)
 		if (ci->platdata->reg_vbus)
 			regulator_disable(ci->platdata->reg_vbus);
 
+		if (ci->platdata->flags & CI_HDRC_PHY_VBUS_CONTROL)
+			usb_phy_vbus_off(ci->usb_phy);
+
 		fsm->a_bus_drop = 1;
 		fsm->a_bus_req = 0;
 	}
diff --git a/include/linux/usb/chipidea.h b/include/linux/usb/chipidea.h
index edf3342..ee38835 100644
--- a/include/linux/usb/chipidea.h
+++ b/include/linux/usb/chipidea.h
@@ -62,6 +62,7 @@ struct ci_hdrc_platform_data {
 #define CI_HDRC_REQUIRES_ALIGNED_DMA	BIT(13)
 #define CI_HDRC_IMX_IS_HSIC		BIT(14)
 #define CI_HDRC_PMQOS			BIT(15)
+#define CI_HDRC_PHY_VBUS_CONTROL	BIT(16)
 	enum usb_dr_mode	dr_mode;
 #define CI_HDRC_CONTROLLER_RESET_EVENT		0
 #define CI_HDRC_CONTROLLER_STOPPED_EVENT	1
-- 
2.7.4