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

[Bryan O'Donoghue <bod@kernel.org>]

On 06/07/2026 13:31, Rakesh Kota wrote:
> 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@oss.qualcomm.com>
> ---
>   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
> 

Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>