[PATCH v3 2/4] regulator: qcom_usb_vbus: add register abstraction and PM8150B support

From: Rakesh Kota

Date: Mon Jul 06 2026 - 10:02:29 EST


Introduce per-compatible regulator descriptor data via struct
qcom_usb_vbus_reg_data to abstract register layout differences between
PMICs. This allows the probe function to dynamically populate the
regulator_desc fields rather than relying on compile-time constants.

Refactor the existing PM8150B support to use this abstraction, wiring in
its CMD_OTG, OTG_CFG, and current-limit registers through pm8150b_data.
No functional change is intended for PM8150B.

Signed-off-by: Rakesh Kota <rakesh.kota@xxxxxxxxxxxxxxxx>
---
drivers/regulator/qcom_usb_vbus-regulator.c | 71 +++++++++++++++++++++++------
1 file changed, 57 insertions(+), 14 deletions(-)

diff --git a/drivers/regulator/qcom_usb_vbus-regulator.c b/drivers/regulator/qcom_usb_vbus-regulator.c
index cd94ed67621fee9f6d7a0327054db0ebab6cc7ee..0201a3983981eec1f475d4b8cdccc9148b5e3b2e 100644
--- a/drivers/regulator/qcom_usb_vbus-regulator.c
+++ b/drivers/regulator/qcom_usb_vbus-regulator.c
@@ -20,6 +20,21 @@
#define OTG_CFG 0x53
#define OTG_EN_SRC_CFG BIT(1)

+struct qcom_usb_vbus_reg_data {
+ u16 cmd_otg;
+ u16 otg_cfg;
+ u8 otg_en_src_cfg;
+ u16 csel_reg;
+ u8 csel_mask;
+ const unsigned int *curr_table;
+ unsigned int n_current_limits;
+ u16 vsel_reg;
+ u8 vsel_mask;
+ const unsigned int *volt_table;
+ unsigned int n_voltages;
+ const struct regulator_ops *ops;
+};
+
static const unsigned int curr_table[] = {
500000, 1000000, 1500000, 2000000, 2500000, 3000000,
};
@@ -32,19 +47,23 @@ static const struct regulator_ops qcom_usb_vbus_reg_ops = {
.set_current_limit = regulator_set_current_limit_regmap,
};

-static struct regulator_desc qcom_usb_vbus_rdesc = {
- .name = "usb_vbus",
- .ops = &qcom_usb_vbus_reg_ops,
- .owner = THIS_MODULE,
- .type = REGULATOR_VOLTAGE,
+static const struct qcom_usb_vbus_reg_data pm8150b_data = {
+ .cmd_otg = CMD_OTG,
+ .otg_cfg = OTG_CFG,
+ .otg_en_src_cfg = OTG_EN_SRC_CFG,
+ .csel_reg = OTG_CURRENT_LIMIT_CFG,
+ .csel_mask = OTG_CURRENT_LIMIT_MASK,
.curr_table = curr_table,
.n_current_limits = ARRAY_SIZE(curr_table),
+ .ops = &qcom_usb_vbus_reg_ops,
};

static int qcom_usb_vbus_regulator_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
+ const struct qcom_usb_vbus_reg_data *data;
struct regulator_dev *rdev;
+ struct regulator_desc *rdesc;
struct regmap *regmap;
struct regulator_config config = { };
struct regulator_init_data *init_data;
@@ -57,27 +76,51 @@ static int qcom_usb_vbus_regulator_probe(struct platform_device *pdev)
return ret;
}

+ data = of_device_get_match_data(dev);
+ if (!data)
+ return -EINVAL;
+
regmap = dev_get_regmap(dev->parent, NULL);
if (!regmap) {
dev_err(dev, "Failed to get regmap\n");
return -ENOENT;
}

- init_data = of_get_regulator_init_data(dev, dev->of_node,
- &qcom_usb_vbus_rdesc);
+ rdesc = devm_kzalloc(dev, sizeof(*rdesc), GFP_KERNEL);
+ if (!rdesc)
+ return -ENOMEM;
+
+ rdesc->name = "usb_vbus";
+ rdesc->ops = data->ops;
+ rdesc->owner = THIS_MODULE;
+ rdesc->type = REGULATOR_VOLTAGE;
+ rdesc->enable_reg = base + data->cmd_otg;
+ rdesc->enable_mask = OTG_EN;
+
+ if (data->curr_table) {
+ rdesc->curr_table = data->curr_table;
+ rdesc->n_current_limits = data->n_current_limits;
+ rdesc->csel_reg = base + data->csel_reg;
+ rdesc->csel_mask = data->csel_mask;
+ }
+
+ if (data->volt_table) {
+ rdesc->volt_table = data->volt_table;
+ rdesc->n_voltages = data->n_voltages;
+ rdesc->vsel_reg = base + data->vsel_reg;
+ rdesc->vsel_mask = data->vsel_mask;
+ }
+
+ init_data = of_get_regulator_init_data(dev, dev->of_node, rdesc);
if (!init_data)
return -ENOMEM;

- qcom_usb_vbus_rdesc.enable_reg = base + CMD_OTG;
- qcom_usb_vbus_rdesc.enable_mask = OTG_EN;
- qcom_usb_vbus_rdesc.csel_reg = base + OTG_CURRENT_LIMIT_CFG;
- qcom_usb_vbus_rdesc.csel_mask = OTG_CURRENT_LIMIT_MASK;
config.dev = dev;
config.init_data = init_data;
config.of_node = dev->of_node;
config.regmap = regmap;

- rdev = devm_regulator_register(dev, &qcom_usb_vbus_rdesc, &config);
+ rdev = devm_regulator_register(dev, rdesc, &config);
if (IS_ERR(rdev)) {
ret = PTR_ERR(rdev);
dev_err(dev, "not able to register vbus reg %d\n", ret);
@@ -85,13 +128,13 @@ static int qcom_usb_vbus_regulator_probe(struct platform_device *pdev)
}

/* Disable HW logic for VBUS enable */
- regmap_update_bits(regmap, base + OTG_CFG, OTG_EN_SRC_CFG, 0);
+ regmap_update_bits(regmap, base + data->otg_cfg, data->otg_en_src_cfg, 0);

return 0;
}

static const struct of_device_id qcom_usb_vbus_regulator_match[] = {
- { .compatible = "qcom,pm8150b-vbus-reg" },
+ { .compatible = "qcom,pm8150b-vbus-reg", .data = &pm8150b_data },
{ }
};
MODULE_DEVICE_TABLE(of, qcom_usb_vbus_regulator_match);

--
2.34.1