[PATCH v2] usb/phy-generic: Add support for OTG VBUS supply control

From: Mike Looijmans
Date: Fri May 29 2020 - 02:02:08 EST


This enables support for VBUS on boards where the power is supplied
by a regulator. The regulator is enabled when the USB port enters
HOST mode.

Signed-off-by: Mike Looijmans <mike.looijmans@xxxxxxxx>
---
v2: Added missing "return 0;" in set_vbus method

.../devicetree/bindings/usb/usb-nop-xceiv.txt | 3 ++
drivers/usb/phy/phy-generic.c | 46 ++++++++++++++++++-
drivers/usb/phy/phy-generic.h | 2 +
3 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
index 4dc6a8ee3071..775a19fdb613 100644
--- a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
+++ b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
@@ -16,6 +16,9 @@ Optional properties:

- vcc-supply: phandle to the regulator that provides power to the PHY.

+- vbus-supply: phandle to the regulator that provides the VBUS power for when
+ the device is in HOST mode.
+
- reset-gpios: Should specify the GPIO for reset.

- vbus-detect-gpio: should specify the GPIO detecting a VBus insertion
diff --git a/drivers/usb/phy/phy-generic.c b/drivers/usb/phy/phy-generic.c
index 661a229c105d..69bf39510e27 100644
--- a/drivers/usb/phy/phy-generic.c
+++ b/drivers/usb/phy/phy-generic.c
@@ -203,13 +203,45 @@ static int nop_set_host(struct usb_otg *otg, struct usb_bus *host)
return 0;
}

+static int nop_set_vbus(struct usb_otg *otg, bool enabled)
+{
+ struct usb_phy_generic *nop;
+ int ret;
+
+ if (!otg)
+ return -ENODEV;
+
+ nop = container_of(otg->usb_phy, struct usb_phy_generic, phy);
+
+ if (!nop->vbus_reg)
+ return 0;
+
+ if (enabled) {
+ if (nop->vbus_reg_enabled)
+ return 0;
+ ret = regulator_enable(nop->vbus_reg);
+ if (ret < 0)
+ return ret;
+ nop->vbus_reg_enabled = true;
+ } else {
+ if (!nop->vbus_reg_enabled)
+ return 0;
+ ret = regulator_disable(nop->vbus_reg);
+ if (ret < 0)
+ return ret;
+ nop->vbus_reg_enabled = false;
+ }
+
+ return 0;
+}
+
int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop)
{
enum usb_phy_type type = USB_PHY_TYPE_USB2;
int err = 0;

u32 clk_rate = 0;
- bool needs_vcc = false, needs_clk = false;
+ bool needs_vcc = false, needs_clk = false, needs_vbus = false;

if (dev->of_node) {
struct device_node *node = dev->of_node;
@@ -219,6 +251,7 @@ int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop)

needs_vcc = of_property_read_bool(node, "vcc-supply");
needs_clk = of_property_read_bool(node, "clocks");
+ needs_vbus = of_property_read_bool(node, "vbus-supply");
}
nop->gpiod_reset = devm_gpiod_get_optional(dev, "reset",
GPIOD_ASIS);
@@ -268,6 +301,16 @@ int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop)
return -EPROBE_DEFER;
}

+ nop->vbus_reg = devm_regulator_get(dev, "vbus");
+ if (IS_ERR(nop->vbus_reg)) {
+ dev_dbg(dev, "Error getting vbus regulator: %ld\n",
+ PTR_ERR(nop->vbus_reg));
+ if (needs_vbus)
+ return -EPROBE_DEFER;
+
+ nop->vbus_reg = NULL;
+ }
+
nop->dev = dev;
nop->phy.dev = nop->dev;
nop->phy.label = "nop-xceiv";
@@ -278,6 +321,7 @@ int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop)
nop->phy.otg->usb_phy = &nop->phy;
nop->phy.otg->set_host = nop_set_host;
nop->phy.otg->set_peripheral = nop_set_peripheral;
+ nop->phy.otg->set_vbus = nop_set_vbus;

return 0;
}
diff --git a/drivers/usb/phy/phy-generic.h b/drivers/usb/phy/phy-generic.h
index 7ee80211a688..a3663639ea1e 100644
--- a/drivers/usb/phy/phy-generic.h
+++ b/drivers/usb/phy/phy-generic.h
@@ -14,7 +14,9 @@ struct usb_phy_generic {
struct gpio_desc *gpiod_reset;
struct gpio_desc *gpiod_vbus;
struct regulator *vbus_draw;
+ struct regulator *vbus_reg;
bool vbus_draw_enabled;
+ bool vbus_reg_enabled;
unsigned long mA;
unsigned int vbus;
};
--
2.17.1