[U-Boot] [PATCH v2 1/4] usb: dwc2: add support for external vbus supply

[Kever Yang]

Some board do not use the dwc2 internal VBUS_DRV signal, but
use a gpio pin to enable the 5.0V VBUS power, add interface to
enable the power in dwc2 driver.

Signed-off-by: Kever Yang <kever.yang at rock-chips.com>
---

Changes in v2: None

 drivers/usb/host/dwc2.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c
index d08879d..8292aa8 100644
--- a/drivers/usb/host/dwc2.c
+++ b/drivers/usb/host/dwc2.c
@@ -15,6 +15,7 @@
 #include <usbroothubdes.h>
 #include <wait_bit.h>
 #include <asm/io.h>
+#include <power/regulator.h>
 
 #include "dwc2.h"
 
@@ -55,6 +56,8 @@ DEFINE_ALIGN_BUFFER(uint8_t, status_buffer_addr, DWC2_STATUS_BUF_SIZE,
 static struct dwc2_priv local;
 #endif
 
+static struct udevice *g_dwc2_udev;
+
 /*
  * DWC2 IP interface
  */
@@ -159,6 +162,29 @@ static void dwc_otg_core_reset(struct dwc2_core_regs *regs)
 	mdelay(100);
 }
 
+static int dwc_vbus_supply_init(void)
+{
+#if defined(CONFIG_DM_USB) && defined(CONFIG_DM_REGULATOR) && \
+	!defined(CONFIG_SPL_BUILD)
+	struct udevice *vbus_supply;
+	int ret;
+
+	ret = device_get_supply_regulator(g_dwc2_udev, "vbus-supply",
+					  &vbus_supply);
+	if (ret) {
+		debug("%s: No vbus supply\n", g_dwc2_udev->name);
+		return 0;
+	}
+
+	ret = regulator_set_enable(vbus_supply, true);
+	if (ret) {
+		error("Error enabling vbus supply\n");
+		return ret;
+	}
+#endif
+	return 0;
+}
+
 /*
  * This function initializes the DWC_otg controller registers for
  * host mode.
@@ -248,6 +274,8 @@ static void dwc_otg_core_host_init(struct dwc2_core_regs *regs)
 			writel(hprt0, &regs->hprt0);
 		}
 	}
+
+	dwc_vbus_supply_init();
 }
 
 /*
@@ -1194,6 +1222,7 @@ static int dwc2_usb_ofdata_to_platdata(struct udevice *dev)
 	const void *prop;
 	fdt_addr_t addr;
 
+	g_dwc2_udev = dev;
 	addr = dev_get_addr(dev);
 	if (addr == FDT_ADDR_T_NONE)
 		return -EINVAL;
-- 
1.9.1