Re: [PATCH v3 4/6] regulator: Add support for QCOM PMIC VBUS booster

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Wed 17 Jun 11:02 PDT 2020, Wesley Cheng wrote:

> Some Qualcomm PMICs have the capability to source the VBUS output to
> connected peripherals.  This driver will register a regulator to the
> regulator list to enable or disable this source by an external driver.
> 
> Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
> ---
>  drivers/regulator/Kconfig                   |  10 ++
>  drivers/regulator/Makefile                  |   1 +
>  drivers/regulator/qcom_usb_vbus-regulator.c | 100 ++++++++++++++++++++
>  3 files changed, 111 insertions(+)
>  create mode 100644 drivers/regulator/qcom_usb_vbus-regulator.c
> 
> diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
> index 074a2ef55943..79d6b7596f0b 100644
> --- a/drivers/regulator/Kconfig
> +++ b/drivers/regulator/Kconfig
> @@ -797,6 +797,16 @@ config REGULATOR_QCOM_SPMI
>  	  Qualcomm SPMI PMICs as a module. The module will be named
>  	  "qcom_spmi-regulator".
>  
> +config REGULATOR_QCOM_USB_VBUS
> +	tristate "Qualcomm USB Vbus regulator driver"
> +	depends on SPMI || COMPILE_TEST
> +	help
> +	  If you say yes to this option, support will be included for the
> +	  regulator used to enable the VBUS output.
> +
> +	  Say M here if you want to include support for enabling the VBUS output
> +	  as a module. The module will be named "qcom_usb_vbus-regulator".
> +
>  config REGULATOR_RC5T583
>  	tristate "RICOH RC5T583 Power regulators"
>  	depends on MFD_RC5T583
> diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
> index c0d6b96ebd78..cbab28aa7b56 100644
> --- a/drivers/regulator/Makefile
> +++ b/drivers/regulator/Makefile
> @@ -89,6 +89,7 @@ obj-$(CONFIG_REGULATOR_QCOM_RPM) += qcom_rpm-regulator.o
>  obj-$(CONFIG_REGULATOR_QCOM_RPMH) += qcom-rpmh-regulator.o
>  obj-$(CONFIG_REGULATOR_QCOM_SMD_RPM) += qcom_smd-regulator.o
>  obj-$(CONFIG_REGULATOR_QCOM_SPMI) += qcom_spmi-regulator.o
> +obj-$(CONFIG_REGULATOR_QCOM_USB_VBUS) += qcom_usb_vbus-regulator.o
>  obj-$(CONFIG_REGULATOR_PALMAS) += palmas-regulator.o
>  obj-$(CONFIG_REGULATOR_PFUZE100) += pfuze100-regulator.o
>  obj-$(CONFIG_REGULATOR_PV88060) += pv88060-regulator.o
> diff --git a/drivers/regulator/qcom_usb_vbus-regulator.c b/drivers/regulator/qcom_usb_vbus-regulator.c
> new file mode 100644
> index 000000000000..fa7a3d891808
> --- /dev/null
> +++ b/drivers/regulator/qcom_usb_vbus-regulator.c
> @@ -0,0 +1,100 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +//
> +// Qualcomm PMIC VBUS output regulator driver
> +//
> +// Copyright (c) 2020, The Linux Foundation. All rights reserved.
> +
> +#include <linux/module.h>
> +#include <linux/err.h>
> +#include <linux/kernel.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/regulator/driver.h>
> +#include <linux/regulator/of_regulator.h>
> +#include <linux/regmap.h>
> +
> +#define CMD_OTG				0x40
> +#define OTG_EN				BIT(0)
> +#define OTG_CFG				0x53
> +#define OTG_EN_SRC_CFG			BIT(1)
> +
> +static const struct regulator_ops qcom_usb_vbus_reg_ops = {
> +	.enable = regulator_enable_regmap,
> +	.disable = regulator_disable_regmap,
> +	.is_enabled = regulator_is_enabled_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 of_device_id qcom_usb_vbus_regulator_match[] = {
> +	{ .compatible = "qcom,pm8150b-vbus-reg" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, qcom_usb_vbus_regulator_match);

Please move the of_device_id below the probe.

> +
> +static int qcom_usb_vbus_regulator_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct regulator_dev *rdev;
> +	struct regmap	*regmap;

Please drop the tab in the middle here.

> +	struct regulator_config config = { };
> +	struct regulator_init_data *init_data;
> +	int ret;
> +	u32 base;
> +
> +	ret = of_property_read_u32(dev->of_node, "reg", &base);
> +	if (ret < 0) {
> +		dev_err(dev, "no base address found\n");
> +		return ret;
> +	}
> +
> +	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);
> +	if (!init_data)
> +		return -ENOMEM;
> +
> +	qcom_usb_vbus_rdesc.enable_reg = base + CMD_OTG;
> +	qcom_usb_vbus_rdesc.enable_mask = OTG_EN;
> +	config.dev = dev;
> +	config.init_data = init_data;
> +	config.regmap = regmap;
> +
> +	rdev = devm_regulator_register(dev, &qcom_usb_vbus_rdesc, &config);
> +	if (IS_ERR(rdev)) {
> +		ret = PTR_ERR(rdev);
> +		dev_err(dev, "not able to register vbus reg %d\n", ret);
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, rdev);

I don't see a matching platform_get_drvdata(), so please omit this.

> +
> +	/* Disable HW logic for VBUS enable */
> +	regmap_update_bits(regmap, base + OTG_CFG, OTG_EN_SRC_CFG, 0);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver qcom_usb_vbus_regulator_driver = {
> +	.driver		= {
> +		.name	= "qcom-usb-vbus-regulator",
> +		.of_match_table = qcom_usb_vbus_regulator_match,
> +	},
> +	.probe		= qcom_usb_vbus_regulator_probe,
> +};
> +module_platform_driver(qcom_usb_vbus_regulator_driver);
> +
> +MODULE_DESCRIPTION("Qualcomm USB vbus regulator driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:qcom-usb-vbus-regulator");

There's no code that will attempt to load the driver by this alias, so
please drop it.

Regards,
Bjorn

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