usb: dwc2: add support for host mode external vbus supply
This patch adds a way to enable an external vbus supply in host mode,
when dwc2 drvvbus signal is not used.
This patch is very similar to the one done in U-Boot dwc2 driver [1]. It
also adds dynamic vbus supply management depending on the role and state
of the core.
[1] https://lists.denx.de/pipermail/u-boot/2017-March/283434.html
Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index 7341d5a..dcfda5e 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -356,6 +356,23 @@ static void dwc2_gusbcfg_init(struct dwc2_hsotg *hsotg)
dwc2_writel(usbcfg, hsotg->regs + GUSBCFG);
}
+static int dwc2_vbus_supply_init(struct dwc2_hsotg *hsotg)
+{
+ hsotg->vbus_supply = devm_regulator_get_optional(hsotg->dev, "vbus");
+ if (IS_ERR(hsotg->vbus_supply))
+ return 0;
+
+ return regulator_enable(hsotg->vbus_supply);
+}
+
+static int dwc2_vbus_supply_exit(struct dwc2_hsotg *hsotg)
+{
+ if (hsotg->vbus_supply)
+ return regulator_disable(hsotg->vbus_supply);
+
+ return 0;
+}
+
/**
* dwc2_enable_host_interrupts() - Enables the Host mode interrupts
*
@@ -3275,6 +3292,7 @@ static void dwc2_conn_id_status_change(struct work_struct *work)
/* B-Device connector (Device Mode) */
if (gotgctl & GOTGCTL_CONID_B) {
+ dwc2_vbus_supply_exit(hsotg);
/* Wait for switch to device mode */
dev_dbg(hsotg->dev, "connId B\n");
if (hsotg->bus_suspended) {
@@ -4323,6 +4341,9 @@ static int _dwc2_hcd_start(struct usb_hcd *hcd)
}
spin_unlock_irqrestore(&hsotg->lock, flags);
+
+ dwc2_vbus_supply_init(hsotg);
+
return 0;
}
@@ -4350,6 +4371,8 @@ static void _dwc2_hcd_stop(struct usb_hcd *hcd)
clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
spin_unlock_irqrestore(&hsotg->lock, flags);
+ dwc2_vbus_supply_exit(hsotg);
+
usleep_range(1000, 3000);
}
@@ -4386,6 +4409,7 @@ static int _dwc2_hcd_suspend(struct usb_hcd *hcd)
hprt0 |= HPRT0_SUSP;
hprt0 &= ~HPRT0_PWR;
dwc2_writel(hprt0, hsotg->regs + HPRT0);
+ dwc2_vbus_supply_exit(hsotg);
}
/* Enter partial_power_down */
@@ -4466,6 +4490,8 @@ static int _dwc2_hcd_resume(struct usb_hcd *hcd)
spin_unlock_irqrestore(&hsotg->lock, flags);
dwc2_port_resume(hsotg);
} else {
+ dwc2_vbus_supply_init(hsotg);
+
/* Wait for controller to correctly update D+/D- level */
usleep_range(3000, 5000);