Re: [RFC PATCH v3 2/5] mfd: add driver for Marvell 88PM886 PMIC

Lee Jones
2024-03-05T11:44:24Z

On Sun, 03 Mar 2024, Karel Balej wrote:

> From: Karel Balej <balejk@matfyz.cz>
>
> Marvell 88PM886 is a PMIC which provides various functions such as
> onkey, battery, charger and regulators. It is found for instance in the
> samsung,coreprimevelte smartphone with which this was tested.
>
> Only implement basic support to allow for the use of regulators and
> onkey omitting the currently unused register definitions and I2C
> subclients which should thus be added with the subdevice drivers which
> need them.
>
> Signed-off-by: Karel Balej <balejk@matfyz.cz>
> ---
>
> Notes:
> RFC v3:
> - Drop onkey cell .of_compatible.
> - Rename LDO page offset and regmap to REGULATORS.
> RFC v2:
> - Remove some abstraction.
> - Sort includes alphabetically and add linux/of.h.
> - Depend on OF, remove of_match_ptr and add MODULE_DEVICE_TABLE.
> - Use more temporaries and break long lines.
> - Do not initialize ret in probe.
> - Use the wakeup-source DT property.
> - Rename ret to err.
> - Address Lee's comments:
> - Drop patched in presets for base regmap and related defines.
> - Use full sentences in comments.
> - Remove IRQ comment.
> - Define regmap_config member values.
> - Rename data to sys_off_data.
> - Add _PMIC suffix to Kconfig.
> - Use dev_err_probe.
> - Do not store irq_data.
> - s/WHOAMI/CHIP_ID

I still see 'whoami'.

> - Drop LINUX part of include guard name.
> - Merge in the regulator series modifications in order to have more
> devices and modify the commit message accordingly. Changes with
> respect to the original regulator series patches:
> - ret -> err
> - Add temporary for dev in pm88x_initialize_subregmaps.
> - Drop of_compatible for the regulators.
> - Do not duplicate LDO regmap for bucks.
> - Rewrite commit message.
>
> drivers/mfd/88pm886.c | 210 ++++++++++++++++++++++++++++++++++++
> drivers/mfd/Kconfig | 12 +++
> drivers/mfd/Makefile | 1 +
> include/linux/mfd/88pm886.h | 46 ++++++++
> 4 files changed, 269 insertions(+)
> create mode 100644 drivers/mfd/88pm886.c
> create mode 100644 include/linux/mfd/88pm886.h
>
> diff --git a/drivers/mfd/88pm886.c b/drivers/mfd/88pm886.c
> new file mode 100644
> index 000000000000..c17220e1b7e2
> --- /dev/null
> +++ b/drivers/mfd/88pm886.c
> @@ -0,0 +1,210 @@
> +// SPDX-License-Identifier: GPL-2.0-only

Header? Description? Author? Copyright?

> +#include <linux/i2c.h>
> +#include <linux/mfd/core.h>
> +#include <linux/module.h>
> +#include <linux/notifier.h>
> +#include <linux/of.h>
> +#include <linux/reboot.h>
> +#include <linux/regmap.h>
> +
> +#include <linux/mfd/88pm886.h>
> +
> +#define PM886_REG_INT_STATUS1 0x05
> +
> +#define PM886_REG_INT_ENA_1 0x0a
> +#define PM886_INT_ENA1_ONKEY BIT(0)
> +
> +#define PM886_REGMAP_CONF_REG_BITS 8
> +#define PM886_REGMAP_CONF_VAL_BITS 8

These 2 are not commonly defined, just the one below please.

> +#define PM886_REGMAP_CONF_MAX_REG 0xfe

> +enum pm886_irq_number {
> + PM886_IRQ_ONKEY,
> +
> + PM886_MAX_IRQ
> +};

Seems superfluous for 1 IRQ and an unused MAX.

Looks like I've mentioned this before.

The IRQ number probably shouldn't be arbitrary either.

> +static struct regmap_irq pm886_regmap_irqs[] = {
> + REGMAP_IRQ_REG(PM886_IRQ_ONKEY, 0, PM886_INT_ENA1_ONKEY),
> +};
> +
> +static struct regmap_irq_chip pm886_regmap_irq_chip = {
> + .name = "88pm886",
> + .irqs = pm886_regmap_irqs,
> + .num_irqs = ARRAY_SIZE(pm886_regmap_irqs),
> + .num_regs = 4,
> + .status_base = PM886_REG_INT_STATUS1,
> + .ack_base = PM886_REG_INT_STATUS1,
> + .unmask_base = PM886_REG_INT_ENA_1,
> +};
> +
> +static struct resource pm886_onkey_resources[] = {
> + DEFINE_RES_IRQ_NAMED(PM886_IRQ_ONKEY, "88pm886-onkey"),
> +};
> +
> +static struct mfd_cell pm886_devs[] = {
> + {
> + .name = "88pm886-onkey",
> + .num_resources = ARRAY_SIZE(pm886_onkey_resources),
> + .resources = pm886_onkey_resources,
> + },
> + {
> + .name = "88pm886-regulator",
> + .id = PM886_REGULATOR_ID_LDO2,

Why doesn't PLATFORM_DEVID_AUTO work for this device?

> + },
> + {
> + .name = "88pm886-regulator",
> + .id = PM886_REGULATOR_ID_LDO15,
> + },
> + {
> + .name = "88pm886-regulator",
> + .id = PM886_REGULATOR_ID_BUCK2,
> + },
> +};
> +
> +static const struct regmap_config pm886_i2c_regmap = {
> + .reg_bits = PM886_REGMAP_CONF_REG_BITS,
> + .val_bits = PM886_REGMAP_CONF_VAL_BITS,
> + .max_register = PM886_REGMAP_CONF_MAX_REG,
> +};
> +
/> +static int pm886_power_off_handler(struct sys_off_data *sys_off_data)
> +{
> + struct pm886_chip *chip = sys_off_data->cb_data;
> + struct regmap *regmap = chip->regmaps[PM886_REGMAP_BASE];
> + struct device *dev = &chip->client->dev;
> + int err;
> +
> + err = regmap_update_bits(regmap, PM886_REG_MISC_CONFIG1, PM886_SW_PDOWN,
> + PM886_SW_PDOWN);
> + if (err) {
> + dev_err(dev, "Failed to power off the device: %d\n", err);
> + return NOTIFY_BAD;
> + }
> + return NOTIFY_DONE;
> +}
> +
> +static int pm886_initialize_subregmaps(struct pm886_chip *chip)
> +{
> + struct device *dev = &chip->client->dev;
> + struct i2c_client *page;
> + struct regmap *regmap;
> + int err;
> +
> + /* regulators page */
> + page = devm_i2c_new_dummy_device(dev, chip->client->adapter,
> + chip->client->addr + PM886_PAGE_OFFSET_REGULATORS);
> + if (IS_ERR(page)) {
> + err = PTR_ERR(page);
> + dev_err(dev, "Failed to initialize regulators client: %d\n", err);
> + return err;
> + }
> + regmap = devm_regmap_init_i2c(page, &pm886_i2c_regmap);
> + if (IS_ERR(regmap)) {
> + err = PTR_ERR(regmap);
> + dev_err(dev, "Failed to initialize regulators regmap: %d\n", err);
> + return err;
> + }
> + chip->regmaps[PM886_REGMAP_REGULATORS] = regmap;

Except for the regulator driver, where else is the regulators regmap used?

> +
> + return 0;
> +}
> +
> +static int pm886_setup_irq(struct pm886_chip *chip,
> + struct regmap_irq_chip_data **irq_data)
> +{
> + struct regmap *regmap = chip->regmaps[PM886_REGMAP_BASE];
> + struct device *dev = &chip->client->dev;
> + int err;
> +
> + /* Set interrupt clearing mode to clear on write. */
> + err = regmap_update_bits(regmap, PM886_REG_MISC_CONFIG2,
> + PM886_INT_INV | PM886_INT_CLEAR | PM886_INT_MASK_MODE,
> + PM886_INT_WC);
> + if (err) {
> + dev_err(dev, "Failed to set interrupt clearing mode: %d\n", err);
> + return err;
> + }
> +
> + err = devm_regmap_add_irq_chip(dev, regmap, chip->client->irq,
> + IRQF_ONESHOT, -1, &pm886_regmap_irq_chip,
> + irq_data);
> + if (err) {
> + dev_err(dev, "Failed to request IRQ: %d\n", err);
> + return err;
> + }
> +
> + return 0;
> +}
> +
> +static int pm886_probe(struct i2c_client *client)
> +{
> + struct regmap_irq_chip_data *irq_data;
> + struct device *dev = &client->dev;
> + struct pm886_chip *chip;
> + struct regmap *regmap;
> + unsigned int chip_id;
> + int err;
> +
> + chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
> + if (!chip)
> + return -ENOMEM;
> +
> + chip->client = client;
> + chip->whoami = (uintptr_t)device_get_match_data(dev);
> + i2c_set_clientdata(client, chip);
> +
> + regmap = devm_regmap_init_i2c(client, &pm886_i2c_regmap);
> + if (IS_ERR(regmap)) {
> + err = PTR_ERR(regmap);
> + return dev_err_probe(dev, err, "Failed to initialize regmap\n");
> + }
> + chip->regmaps[PM886_REGMAP_BASE] = regmap;
> +
> + err = regmap_read(regmap, PM886_REG_ID, &chip_id);
> + if (err)
> + return dev_err_probe(dev, err, "Failed to read chip ID\n");

'\n'

> + if (chip->whoami != chip_id)
> + return dev_err_probe(dev, -EINVAL, "Device reported wrong chip ID: %u\n",

"Unsupported chip"

> + chip_id);

How many chars does this take up if on one line?

Nit: If you have to break, break after the "-EINVAL" param.

> +
> + err = pm886_initialize_subregmaps(chip);
> + if (err)
> + return err;
> +
> + err = pm886_setup_irq(chip, &irq_data);
> + if (err)
> + return err;
> +
> + err = devm_mfd_add_devices(dev, 0, pm886_devs, ARRAY_SIZE(pm886_devs),
> + NULL, 0, regmap_irq_get_domain(irq_data));
> + if (err)
> + return dev_err_probe(dev, err, "Failed to add devices\n");
> +
> + err = devm_register_power_off_handler(dev, pm886_power_off_handler, chip);
> + if (err)
> + return dev_err_probe(dev, err, "Failed to register power off handler\n");
> +
> + device_init_wakeup(dev, device_property_read_bool(dev, "wakeup-source"));
> +
> + return 0;
> +}
> +
> +const struct of_device_id pm886_of_match[] = {
> + { .compatible = "marvell,88pm886-a1", .data = (void *)PM886_A1_CHIP_ID },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, pm886_of_match);
> +
> +static struct i2c_driver pm886_i2c_driver = {
> + .driver = {
> + .name = "88pm886",
> + .of_match_table = pm886_of_match,
> + },
> + .probe = pm886_probe,
> +};
> +module_i2c_driver(pm886_i2c_driver);
> +
> +MODULE_DESCRIPTION("Marvell 88PM886 PMIC driver");
> +MODULE_AUTHOR("Karel Balej <balejk@matfyz.cz>");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index e7a6e45b9fac..9ef921c59f30 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -794,6 +794,18 @@ config MFD_88PM860X
> select individual components like voltage regulators, RTC and
> battery-charger under the corresponding menus.
>
> +config MFD_88PM886_PMIC
> + bool "Marvell 88PM886 PMIC"
> + depends on I2C=y
> + depends on OF
> + select REGMAP_I2C
> + select REGMAP_IRQ
> + select MFD_CORE
> + help
> + This enables support for Marvell 88PM886 Power Management IC.
> + This includes the I2C driver and the core APIs _only_, you have to
> + select individual components like onkey under the corresponding menus.
> +
> config MFD_MAX14577
> tristate "Maxim Semiconductor MAX14577/77836 MUIC + Charger Support"
> depends on I2C
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index c66f07edcd0e..d016b7fed354 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -7,6 +7,7 @@
> obj-$(CONFIG_MFD_88PM860X) += 88pm860x.o
> obj-$(CONFIG_MFD_88PM800) += 88pm800.o 88pm80x.o
> obj-$(CONFIG_MFD_88PM805) += 88pm805.o 88pm80x.o
> +obj-$(CONFIG_MFD_88PM886_PMIC) += 88pm886.o
> obj-$(CONFIG_MFD_ACT8945A) += act8945a.o
> obj-$(CONFIG_MFD_SM501) += sm501.o
> obj-$(CONFIG_ARCH_BCM2835) += bcm2835-pm.o
> diff --git a/include/linux/mfd/88pm886.h b/include/linux/mfd/88pm886.h
> new file mode 100644
> index 000000000000..c7527bab0fba
> --- /dev/null
> +++ b/include/linux/mfd/88pm886.h
> @@ -0,0 +1,46 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +#ifndef __MFD_88PM886_H
> +#define __MFD_88PM886_H
> +
> +#include <linux/mfd/core.h>

What's this for?

> +#define PM886_A1_CHIP_ID 0xa1
> +
> +#define PM886_REG_ID 0x00
> +
> +#define PM886_REG_STATUS1 0x01
> +#define PM886_ONKEY_STS1 BIT(0)
> +
> +#define PM886_REG_MISC_CONFIG1 0x14
> +#define PM886_SW_PDOWN BIT(5)
> +
> +#define PM886_REG_MISC_CONFIG2 0x15
> +#define PM886_INT_INV BIT(0)
> +#define PM886_INT_CLEAR BIT(1)
> +#define PM886_INT_RC 0x00
> +#define PM886_INT_WC BIT(1)
> +#define PM886_INT_MASK_MODE BIT(2)
> +
> +#define PM886_PAGE_OFFSET_REGULATORS 1
> +
> +enum pm886_regulator_id {
> + PM886_REGULATOR_ID_LDO2,
> + PM886_REGULATOR_ID_LDO15,
> + PM886_REGULATOR_ID_BUCK2,
> +
> + PM886_REGULATOR_ID_SENTINEL
> +};
> +
> +enum pm886_regmap_index {
> + PM886_REGMAP_BASE,
> + PM886_REGMAP_REGULATORS,
> +
> + PM886_REGMAP_NR
> +};
> +
> +struct pm886_chip {
> + struct i2c_client *client;
> + unsigned int whoami;

chip_id

> + struct regmap *regmaps[PM886_REGMAP_NR];
> +};
> +#endif /* __MFD_88PM886_H */
> --
> 2.44.0
>

--
Lee Jones [李琼斯]