[PATCH v4 10/22] phy: renesas: rcar-gen3-usb2: Add regulator for OTG VBUS control

Tommaso Merciai
2025-11-21T15:14:15Z

Enable OTG VBUS control on R-Car Gen3 USB2 PHY by registering a regulator
driver that manages the VBOUT line. This change allows the controller to
handle VBUS output for OTG ports using the regulator framework when the
platform requires hardware-based VBUS control.

Without this, some platforms cannot properly manage VBUS power on OTG-
capable ports, leading to potential USB functionality issues.

Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@bp.renesas.com>
---
v3->v4:
- No changes

v2->v3:
- No changes

v1->v2:
- No changes

drivers/phy/renesas/phy-rcar-gen3-usb2.c | 142 ++++++++++++++++++++++-
1 file changed, 137 insertions(+), 5 deletions(-)

diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
index 94a4521d7187..d2c03a846b58 100644
--- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c
+++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
@@ -22,6 +22,7 @@
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
+#include <linux/regulator/driver.h>
#include <linux/reset.h>
#include <linux/string.h>
#include <linux/usb/of.h>
@@ -141,6 +142,7 @@ struct rcar_gen3_chan {
bool extcon_host;
bool is_otg_channel;
bool uses_otg_pins;
+ bool otg_internal_reg;
};

struct rcar_gen3_phy_drv_data {
@@ -225,6 +227,11 @@ static void rcar_gen3_phy_usb2_set_vbus(struct rcar_gen3_chan *ch,

static void rcar_gen3_enable_vbus_ctrl(struct rcar_gen3_chan *ch, int vbus)
{
+ if (ch->otg_internal_reg) {
+ regulator_hardware_enable(ch->vbus, vbus);
+ return;
+ }
+
if (ch->phy_data->no_adp_ctrl || ch->phy_data->vblvl_ctrl) {
if (ch->vbus)
regulator_hardware_enable(ch->vbus, vbus);
@@ -593,7 +600,7 @@ static int rcar_gen3_phy_usb2_power_on(struct phy *p)
u32 val;
int ret = 0;

- if (channel->vbus) {
+ if (channel->vbus && !channel->otg_internal_reg) {
ret = regulator_enable(channel->vbus);
if (ret)
return ret;
@@ -634,7 +641,7 @@ static int rcar_gen3_phy_usb2_power_off(struct phy *p)
}
}

- if (channel->vbus)
+ if (channel->vbus && !channel->otg_internal_reg)
ret = regulator_disable(channel->vbus);

return ret;
@@ -809,6 +816,128 @@ static int rcar_gen3_phy_usb2_init_bus(struct rcar_gen3_chan *channel)
return 0;
}

+static int rcar_gen3_phy_usb2_regulator_endisable(struct regulator_dev *rdev,
+ bool enable)
+{
+ struct rcar_gen3_chan *channel = rdev_get_drvdata(rdev);
+ struct device *dev = channel->dev;
+ int ret;
+
+ ret = pm_runtime_resume_and_get(dev);
+ if (ret < 0) {
+ dev_warn(dev, "pm_runtime_get failed: %i\n", ret);
+ return ret;
+ }
+
+ rcar_gen3_phy_usb2_set_vbus(channel, USB2_VBCTRL,
+ USB2_VBCTRL_VBOUT, enable);
+ pm_runtime_put_noidle(dev);
+
+ return ret;
+}
+
+static int rcar_gen3_phy_usb2_regulator_enable(struct regulator_dev *rdev)
+{
+ return rcar_gen3_phy_usb2_regulator_endisable(rdev, true);
+}
+
+static int rcar_gen3_phy_usb2_regulator_disable(struct regulator_dev *rdev)
+{
+ return rcar_gen3_phy_usb2_regulator_endisable(rdev, false);
+}
+
+static int rcar_gen3_phy_usb2_regulator_is_enabled(struct regulator_dev *rdev)
+{
+ struct rcar_gen3_chan *channel = rdev_get_drvdata(rdev);
+ void __iomem *usb2_base = channel->base;
+ struct device *dev = channel->dev;
+ u32 vbus_ctrl_reg = USB2_VBCTRL;
+ u32 val;
+ int ret;
+
+ ret = pm_runtime_resume_and_get(dev);
+ if (ret < 0) {
+ dev_warn(dev, "pm_runtime_get failed: %i\n", ret);
+ return ret;
+ }
+
+ val = readl(usb2_base + vbus_ctrl_reg);
+
+ pm_runtime_put_noidle(dev);
+ dev_dbg(channel->dev, "%s: %08x\n", __func__, val);
+
+ return (val & USB2_VBCTRL_VBOUT) ? 1 : 0;
+}
+
+static const struct regulator_ops rcar_gen3_phy_usb2_regulator_ops = {
+ .enable = rcar_gen3_phy_usb2_regulator_enable,
+ .disable = rcar_gen3_phy_usb2_regulator_disable,
+ .is_enabled = rcar_gen3_phy_usb2_regulator_is_enabled,
+};
+
+static const struct regulator_desc rcar_gen3_phy_usb2_regulator = {
+ .name = "otg-vbus-regulator",
+ .of_match = of_match_ptr("vbus-regulator"),
+ .ops = &rcar_gen3_phy_usb2_regulator_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ .fixed_uV = 5000000,
+ .n_voltages = 1,
+};
+
+static void rcar_gen3_phy_usb2_vbus_disable_action(void *data)
+{
+ struct regulator *vbus = data;
+
+ regulator_disable(vbus);
+}
+
+static int rcar_gen3_phy_usb2_vbus_regulator_get_exclusive_enable(struct rcar_gen3_chan *channel,
+ bool enable)
+{
+ struct device *dev = channel->dev;
+ int ret;
+
+ channel->vbus = devm_regulator_get_exclusive(dev, "vbus");
+ if (IS_ERR(channel->vbus))
+ return PTR_ERR(channel->vbus);
+
+ if (!enable)
+ return 0;
+
+ ret = regulator_enable(channel->vbus);
+ if (ret)
+ return ret;
+
+ return devm_add_action_or_reset(dev, rcar_gen3_phy_usb2_vbus_disable_action,
+ channel->vbus);
+}
+
+static int rcar_gen3_phy_usb2_vbus_regulator_register(struct rcar_gen3_chan *channel)
+{
+ struct device *dev = channel->dev;
+ struct regulator_config rcfg = { .dev = dev, };
+ struct regulator_dev *rdev;
+ bool enable = false;
+
+ rcfg.of_node = of_get_available_child_by_name(dev->of_node,
+ "vbus-regulator");
+ if (rcfg.of_node) {
+ rcfg.driver_data = channel;
+ rdev = devm_regulator_register(dev, &rcar_gen3_phy_usb2_regulator,
+ &rcfg);
+ of_node_put(rcfg.of_node);
+ if (IS_ERR(rdev))
+ return dev_err_probe(dev, PTR_ERR(rdev),
+ "Failed to create vbus-regulator\n");
+
+ channel->otg_internal_reg = true;
+ enable = true;
+ }
+
+ return rcar_gen3_phy_usb2_vbus_regulator_get_exclusive_enable(channel, enable);
+}
+
static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -890,10 +1019,13 @@ static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev)
phy_set_drvdata(channel->rphys[i].phy, &channel->rphys[i]);
}

- if (channel->phy_data->no_adp_ctrl && channel->is_otg_channel)
- channel->vbus = devm_regulator_get_exclusive(dev, "vbus");
- else
+ if (channel->phy_data->no_adp_ctrl && channel->is_otg_channel) {
+ ret = rcar_gen3_phy_usb2_vbus_regulator_register(channel);
+ if (ret)
+ return ret;
+ } else {
channel->vbus = devm_regulator_get_optional(dev, "vbus");
+ }
if (IS_ERR(channel->vbus)) {
if (PTR_ERR(channel->vbus) == -EPROBE_DEFER)
return PTR_ERR(channel->vbus);
--
2.43.0