[PATCH v2] usb: dwc3: Add support for VBUS power control

From: Mike Looijmans
Date: Wed Jun 03 2020 - 08:09:26 EST


Support VBUS power control using regulator framework. Enables the regulator
while the port is in host mode.

Signed-off-by: Mike Looijmans <mike.looijmans@xxxxxxxx>
---
v2: Add missing devm_regulator_get call which got lost during rebase

.../devicetree/bindings/usb/dwc3.txt | 1 +
drivers/usb/dwc3/core.c | 34 ++++++++++++++-----
drivers/usb/dwc3/core.h | 4 +++
drivers/usb/dwc3/drd.c | 6 ++--
4 files changed, 33 insertions(+), 12 deletions(-)

diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
index 9946ff9ba735..56bc3f238e2d 100644
--- a/Documentation/devicetree/bindings/usb/dwc3.txt
+++ b/Documentation/devicetree/bindings/usb/dwc3.txt
@@ -37,6 +37,7 @@ Optional properties:
- phys: from the *Generic PHY* bindings
- phy-names: from the *Generic PHY* bindings; supported names are "usb2-phy"
or "usb3-phy".
+ - vbus-supply: Regulator handle that provides the VBUS power.
- resets: set of phandle and reset specifier pairs
- snps,usb2-lpm-disable: indicate if we don't want to enable USB2 HW LPM
- snps,usb3_lpm_capable: determines if platform is USB3 LPM capable
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index edc17155cb2b..ad341a182999 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -25,6 +25,7 @@
#include <linux/of.h>
#include <linux/acpi.h>
#include <linux/pinctrl/consumer.h>
+#include <linux/regulator/consumer.h>
#include <linux/reset.h>

#include <linux/usb/ch9.h>
@@ -112,6 +113,23 @@ void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode)
dwc->current_dr_role = mode;
}

+void dwc3_set_vbus(struct dwc3 *dwc, bool enable)
+{
+ int ret;
+
+ if (enable != dwc->vbus_reg_enabled) {
+ if (enable)
+ ret = regulator_enable(dwc->vbus_reg);
+ else
+ ret = regulator_disable(dwc->vbus_reg);
+ if (!ret)
+ dwc->vbus_reg_enabled = enable;
+ }
+
+ if (dwc->usb2_phy)
+ otg_set_vbus(dwc->usb2_phy->otg, enable);
+}
+
static void __dwc3_set_mode(struct work_struct *work)
{
struct dwc3 *dwc = work_to_dwc(work);
@@ -164,8 +182,7 @@ static void __dwc3_set_mode(struct work_struct *work)
if (ret) {
dev_err(dwc->dev, "failed to initialize host\n");
} else {
- if (dwc->usb2_phy)
- otg_set_vbus(dwc->usb2_phy->otg, true);
+ dwc3_set_vbus(dwc, true);
phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
phy_set_mode(dwc->usb3_generic_phy, PHY_MODE_USB_HOST);
}
@@ -173,8 +190,7 @@ static void __dwc3_set_mode(struct work_struct *work)
case DWC3_GCTL_PRTCAP_DEVICE:
dwc3_event_buffers_setup(dwc);

- if (dwc->usb2_phy)
- otg_set_vbus(dwc->usb2_phy->otg, false);
+ dwc3_set_vbus(dwc, false);
phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_DEVICE);
phy_set_mode(dwc->usb3_generic_phy, PHY_MODE_USB_DEVICE);

@@ -1183,8 +1199,7 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)
case USB_DR_MODE_PERIPHERAL:
dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_DEVICE);

- if (dwc->usb2_phy)
- otg_set_vbus(dwc->usb2_phy->otg, false);
+ dwc3_set_vbus(dwc, false);
phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_DEVICE);
phy_set_mode(dwc->usb3_generic_phy, PHY_MODE_USB_DEVICE);

@@ -1198,8 +1213,7 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)
case USB_DR_MODE_HOST:
dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);

- if (dwc->usb2_phy)
- otg_set_vbus(dwc->usb2_phy->otg, true);
+ dwc3_set_vbus(dwc, true);
phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
phy_set_mode(dwc->usb3_generic_phy, PHY_MODE_USB_HOST);

@@ -1470,6 +1484,10 @@ static int dwc3_probe(struct platform_device *pdev)

dwc3_get_properties(dwc);

+ dwc->vbus_reg = devm_regulator_get_optional(dev, "vbus");
+ if (IS_ERR(dwc->vbus_reg))
+ return PTR_ERR(dwc->vbus_reg);
+
dwc->reset = devm_reset_control_array_get(dev, true, true);
if (IS_ERR(dwc->reset))
return PTR_ERR(dwc->reset);
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 4c171a8e215f..cee2574d7bf4 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1085,6 +1085,9 @@ struct dwc3 {

bool phys_ready;

+ struct regulator *vbus_reg;
+ bool vbus_reg_enabled;
+
struct ulpi *ulpi;
bool ulpi_ready;

@@ -1397,6 +1400,7 @@ struct dwc3_gadget_ep_cmd_params {

/* prototypes */
void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode);
+void dwc3_set_vbus(struct dwc3 *dwc, bool enable);
void dwc3_set_mode(struct dwc3 *dwc, u32 mode);
u32 dwc3_core_fifo_space(struct dwc3_ep *dep, u8 type);

diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c
index 7db1ffc92bbd..45fdec2d128d 100644
--- a/drivers/usb/dwc3/drd.c
+++ b/drivers/usb/dwc3/drd.c
@@ -384,8 +384,7 @@ void dwc3_otg_update(struct dwc3 *dwc, bool ignore_idstatus)
if (ret) {
dev_err(dwc->dev, "failed to initialize host\n");
} else {
- if (dwc->usb2_phy)
- otg_set_vbus(dwc->usb2_phy->otg, true);
+ dwc3_set_vbus(dwc, true);
if (dwc->usb2_generic_phy)
phy_set_mode(dwc->usb2_generic_phy,
PHY_MODE_USB_HOST);
@@ -398,8 +397,7 @@ void dwc3_otg_update(struct dwc3 *dwc, bool ignore_idstatus)
dwc3_event_buffers_setup(dwc);
spin_unlock_irqrestore(&dwc->lock, flags);

- if (dwc->usb2_phy)
- otg_set_vbus(dwc->usb2_phy->otg, false);
+ dwc3_set_vbus(dwc, false);
if (dwc->usb2_generic_phy)
phy_set_mode(dwc->usb2_generic_phy,
PHY_MODE_USB_DEVICE);
--
2.17.1