Re: [PATCH 12/13] regulator: add pm8008 pmic regulator driver

Andy Shevchenko
2024-05-06T19:09:54Z

Mon, May 06, 2024 at 05:08:29PM +0200, Johan Hovold kirjoitti:
> From: Satya Priya <quic_c_skakit@quicinc.com>
>
> Qualcomm Technologies, Inc. PM8008 is an I2C-controlled PMIC containing
> seven LDO regulators. Add a PM8008 regulator driver to support PMIC
> regulator management via the regulator framework.
>
> Note that this driver, originally submitted by Satya Priya [1], has been
> reworked to match the new devicetree binding which no longer describes
> each regulator as a separate device.
>
> This avoids describing internal details like register offsets in the
> devicetree and allows for extending the implementation with features
> like over-current protection without having to update the binding.
>
> Specifically note that the regulator interrupts are shared between all
> regulators.
>
> Note that the secondary regmap is looked up by name and that if the
> driver ever needs to be generalised to support regulators provided by
> the primary regmap (I2C address) such information could be added to a
> driver lookup table matching on the parent compatible.
>
> This also fixes the original implementation, which looked up regulators
> by 'regulator-name' property rather than devicetree node name and which
> prevented the regulators from being named to match board schematics.

> [1] https://lore.kernel.org/r/1655200111-18357-8-git-send-email-quic_c_skakit@quicinc.com

Make it Link: tag?

Link: URL [1]

...

> [ johan: rework probe to match new binding, amend commit message and
> Kconfig entry]

Wouldn't be better on one line?

...

+ array_size.h
+ bits.h

> +#include <linux/device.h>

> +#include <linux/kernel.h>

What is this header for?

+ math.h

> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/driver.h>

+ asm/byteorder.h

...

> +static int pm8008_regulator_get_voltage(struct regulator_dev *rdev)
> +{
> + struct pm8008_regulator *pm8008_reg = rdev_get_drvdata(rdev);
> + __le16 mV;
> + int uV;
> +
> + regmap_bulk_read(pm8008_reg->regmap,
> + LDO_VSET_LB_REG(pm8008_reg->base), (void *)&mV, 2);

Why casting?

> + uV = le16_to_cpu(mV) * 1000;
> + return (uV - pm8008_reg->rdesc.min_uV) / pm8008_reg->rdesc.uV_step;
> +}
> +
> +static inline int pm8008_write_voltage(struct pm8008_regulator *pm8008_reg,
> + int mV)
> +{
> + __le16 vset_raw;
> +
> + vset_raw = cpu_to_le16(mV);

Can be joined to a single line.

> + return regmap_bulk_write(pm8008_reg->regmap,
> + LDO_VSET_LB_REG(pm8008_reg->base),
> + (const void *)&vset_raw, sizeof(vset_raw));

Why casting?

> +}

...

> +static int pm8008_regulator_set_voltage(struct regulator_dev *rdev,
> + unsigned int selector)
> +{
> + struct pm8008_regulator *pm8008_reg = rdev_get_drvdata(rdev);
> + int rc, mV;
> +
> + rc = regulator_list_voltage_linear_range(rdev, selector);
> + if (rc < 0)
> + return rc;
> +
> + /* voltage control register is set with voltage in millivolts */
> + mV = DIV_ROUND_UP(rc, 1000);

> + rc = pm8008_write_voltage(pm8008_reg, mV);
> + if (rc < 0)
> + return rc;
> +
> + return 0;

return pm8008_write_voltage(pm8008_reg, mV);

?

> +}

> +
> + regmap = dev_get_regmap(dev->parent, "secondary");
> + if (!regmap)
> + return -EINVAL;
> +
> + for (i = 0; i < ARRAY_SIZE(reg_data); i++) {
> + pm8008_reg = devm_kzalloc(dev, sizeof(*pm8008_reg), GFP_KERNEL);
> + if (!pm8008_reg)
> + return -ENOMEM;
> +
> + pm8008_reg->regmap = regmap;
> + pm8008_reg->base = reg_data[i].base;
> +
> + /* get slew rate */
> + rc = regmap_bulk_read(pm8008_reg->regmap,
> + LDO_STEPPER_CTL_REG(pm8008_reg->base), &val, 1);
> + if (rc < 0) {
> + dev_err(dev, "failed to read step rate: %d\n", rc);
> + return rc;

return dev_err_probe(...);

> + }
> + val &= STEP_RATE_MASK;
> + pm8008_reg->step_rate = DEFAULT_VOLTAGE_STEPPER_RATE >> val;

> + rdesc = &pm8008_reg->rdesc;
> + rdesc->type = REGULATOR_VOLTAGE;
> + rdesc->ops = &pm8008_regulator_ops;
> + rdesc->name = reg_data[i].name;
> + rdesc->supply_name = reg_data[i].supply_name;
> + rdesc->of_match = reg_data[i].name;
> + rdesc->uV_step = VSET_STEP_UV;
> + rdesc->linear_ranges = reg_data[i].voltage_range;
> + rdesc->n_linear_ranges = 1;
> + BUILD_BUG_ON((ARRAY_SIZE(pldo_ranges) != 1) ||
> + (ARRAY_SIZE(nldo_ranges) != 1));
> +
> + if (reg_data[i].voltage_range == nldo_ranges) {
> + rdesc->min_uV = NLDO_MIN_UV;
> + rdesc->n_voltages = ((NLDO_MAX_UV - NLDO_MIN_UV) / rdesc->uV_step) + 1;
> + } else {
> + rdesc->min_uV = PLDO_MIN_UV;
> + rdesc->n_voltages = ((PLDO_MAX_UV - PLDO_MIN_UV) / rdesc->uV_step) + 1;
> + }
> +
> + rdesc->enable_reg = LDO_ENABLE_REG(pm8008_reg->base);
> + rdesc->enable_mask = ENABLE_BIT;
> + rdesc->min_dropout_uV = reg_data[i].min_dropout_uv;
> + rdesc->regulators_node = of_match_ptr("regulators");
> +
> + reg_config.dev = dev->parent;
> + reg_config.driver_data = pm8008_reg;
> + reg_config.regmap = pm8008_reg->regmap;
> +
> + rdev = devm_regulator_register(dev, rdesc, &reg_config);
> + if (IS_ERR(rdev)) {

> + rc = PTR_ERR(rdev);
> + dev_err(dev, "failed to register regulator %s: %d\n",
> + reg_data[i].name, rc);
> + return rc;

return dev_err_probe(...);

> + }
> + }
> +
> + return 0;
> +}

...

> +static struct platform_driver pm8008_regulator_driver = {
> + .driver = {
> + .name = "qcom-pm8008-regulator",
> + },
> + .probe = pm8008_regulator_probe,
> +};

> +

Unneeded blank line.

> +module_platform_driver(pm8008_regulator_driver);

...

> +MODULE_ALIAS("platform:qcom-pm8008-regulator");

Use ID table instead.

--
With Best Regards,
Andy Shevchenko