Re: [PATCH v9 1/2] mfd: bd71837: mfd driver for ROHM BD71837 PMIC

[Lee Jones <lee.jones@linaro.org>]

On Thu, 05 Jul 2018, Matti Vaittinen wrote:

> ROHM BD71837 PMIC MFD driver providing interrupts and support
> for three subsystems:
> - clk
> - Regulators
> - input/power-key
> 
> Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
> ---
>  drivers/mfd/Kconfig         |  13 ++
>  drivers/mfd/Makefile        |   1 +
>  drivers/mfd/bd71837.c       | 215 ++++++++++++++++++++++++
>  include/linux/mfd/bd71837.h | 391 ++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 620 insertions(+)
>  create mode 100644 drivers/mfd/bd71837.c
>  create mode 100644 include/linux/mfd/bd71837.h
> 
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index b860eb5aa194..d01a279f5e4a 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -1787,6 +1787,19 @@ config MFD_STW481X
>  	  in various ST Microelectronics and ST-Ericsson embedded
>  	  Nomadik series.
>  
> +config MFD_BD71837

It's be nice if you prefix this with the manufacturer.  Rohm?

> +	tristate "BD71837 Power Management chip"

Again, missing manufacturer.

This should also be "Power Management IC"

> +	depends on I2C=y
> +	depends on OF
> +	select REGMAP_I2C
> +	select REGMAP_IRQ
> +	select MFD_CORE
> +	help
> +	  Select this option to get support for the ROHM BD71837
> +	  Power Management chips. BD71837 is designed to power processors like

"chips" is slang.  Should be "ICs".

> +	  NXP i.MX8. It contains 8 BUCK outputs and 7 LDOs, voltage monitoring
> +	  and emergency shut down as well as 32,768KHz clock output.
> +
>  config MFD_STM32_LPTIMER
>  	tristate "Support for STM32 Low-Power Timer"
>  	depends on (ARCH_STM32 && OF) || COMPILE_TEST
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index e9fd20dba18d..09dc9eb3782c 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -227,4 +227,5 @@ obj-$(CONFIG_MFD_STM32_TIMERS) 	+= stm32-timers.o
>  obj-$(CONFIG_MFD_MXS_LRADC)     += mxs-lradc.o
>  obj-$(CONFIG_MFD_SC27XX_PMIC)	+= sprd-sc27xx-spi.o
>  obj-$(CONFIG_RAVE_SP_CORE)	+= rave-sp.o
> +obj-$(CONFIG_MFD_BD71837)	+= bd71837.o
>  
> diff --git a/drivers/mfd/bd71837.c b/drivers/mfd/bd71837.c

rohm-bd71837.c would be nicer.

> new file mode 100644
> index 000000000000..677097bcea17
> --- /dev/null
> +++ b/drivers/mfd/bd71837.c
> @@ -0,0 +1,215 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later

'\n' here please.

> +// Copyright (C) 2018 ROHM Semiconductors

'\n' here please.

> +// bd71837.c -- ROHM BD71837MWV mfd driver

Remove the filename -- they have a habit of becoming incorrect.

Also, and 'MFD driver' isn't a thing -- this is a PMIC driver.

> +// Datasheet available from
> +// https://www.rohm.com/datasheet/BD71837MWV/bd71837mwv-e
> +
> +#include <linux/i2c.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/mfd/bd71837.h>
> +#include <linux/mfd/core.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/gpio_keys.h>

Alphabetical please.

> +static struct gpio_keys_button btns[] = {
> +	{
> +		.code = KEY_POWER,
> +		.gpio = -1,
> +		.type = EV_KEY,
> +	},
> +};

Does this need to be an array?

> +static struct gpio_keys_platform_data bd718xx_powerkey_data = {
> +	.buttons = &btns[0],

Why not just "btns"?

Also, I don't see any reason not to just call this 'buttons'.

Or even, 'button' if there will only ever be one of them.

> +	.nbuttons = ARRAY_SIZE(btns),
> +	.name = "bd718xx-pwrkey",
> +};
> +
> +static struct mfd_cell bd71837_mfd_cells[] = {
> +	{
> +		.name = "bd71837-clk",
> +	}, {
> +		.name = "gpio-keys",
> +		.platform_data = &bd718xx_powerkey_data,
> +		.pdata_size = sizeof(bd718xx_powerkey_data),
> +	}, {
> +		.name = "bd71837-pmic",
> +	},
> +};

Place the one line entries on one line, like this:

	{ .name = "bd71837-pmic", },

... and if ordering is not important, place them at the bottom.

> +static const struct regmap_irq bd71837_irqs[] = {
> +	REGMAP_IRQ_REG(BD71837_INT_SWRST, 0, BD71837_INT_SWRST_MASK),
> +	REGMAP_IRQ_REG(BD71837_INT_PWRBTN_S, 0, BD71837_INT_PWRBTN_S_MASK),
> +	REGMAP_IRQ_REG(BD71837_INT_PWRBTN_L, 0, BD71837_INT_PWRBTN_L_MASK),
> +	REGMAP_IRQ_REG(BD71837_INT_PWRBTN, 0, BD71837_INT_PWRBTN_MASK),
> +	REGMAP_IRQ_REG(BD71837_INT_WDOG, 0, BD71837_INT_WDOG_MASK),
> +	REGMAP_IRQ_REG(BD71837_INT_ON_REQ, 0, BD71837_INT_ON_REQ_MASK),
> +	REGMAP_IRQ_REG(BD71837_INT_STBY_REQ, 0, BD71837_INT_STBY_REQ_MASK),
> +};
> +
> +static struct regmap_irq_chip bd71837_irq_chip = {
> +	.name = "bd71837-irq",
> +	.irqs = bd71837_irqs,
> +	.num_irqs = ARRAY_SIZE(bd71837_irqs),
> +	.num_regs = 1,
> +	.irq_reg_stride = 1,
> +	.status_base = BD71837_REG_IRQ,
> +	.mask_base = BD71837_REG_MIRQ,
> +	.ack_base = BD71837_REG_IRQ,
> +	.init_ack_masked = true,
> +	.mask_invert = false,
> +};
> +
> +static const struct regmap_range pmic_status_range = {
> +	.range_min = BD71837_REG_IRQ,
> +	.range_max = BD71837_REG_POW_STATE,
> +};
> +
> +static const struct regmap_access_table volatile_regs = {
> +	.yes_ranges = &pmic_status_range,
> +	.n_yes_ranges = 1,
> +};
> +
> +static const struct regmap_config bd71837_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.volatile_table = &volatile_regs,
> +	.max_register = BD71837_MAX_REGISTER - 1,
> +	.cache_type = REGCACHE_RBTREE,
> +};
> +
> +static const struct of_device_id bd71837_of_match[] = {
> +	{ .compatible = "rohm,bd71837", },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, bd71837_of_match);
> +
> +static int bd71837_i2c_probe(struct i2c_client *i2c,
> +			    const struct i2c_device_id *id)
> +{
> +	struct bd71837 *bd71837;
> +	struct bd71837_board *board_info;
> +	int ret = -EINVAL;

I'd prefer it if you set the error at the location it happened for
readability.

> +	bd71837 = devm_kzalloc(&i2c->dev, sizeof(struct bd71837), GFP_KERNEL);
> +

Drop this line.

> +	if (!bd71837)
> +		return -ENOMEM;
> +
> +	board_info = dev_get_platdata(&i2c->dev);
> +
> +	if (!board_info)
> +		bd71837->chip_irq = i2c->irq;
> +	else
> +		bd71837->chip_irq = board_info->gpio_intr;
> +
> +	if (!bd71837->chip_irq) {
> +		dev_err(&i2c->dev, "No IRQ configured\n");
> +		goto err_out;
> +	}
> +
> +	bd71837->dev = &i2c->dev;
> +	bd71837->i2c_client = i2c;
> +	i2c_set_clientdata(i2c, bd71837);
> +
> +	bd71837->regmap = devm_regmap_init_i2c(i2c, &bd71837_regmap_config);
> +	if (IS_ERR(bd71837->regmap)) {
> +		ret = PTR_ERR(bd71837->regmap);
> +		dev_err(&i2c->dev, "regmap initialization failed\n");
> +		goto err_out;
> +	}
> +
> +	ret = bd71837_reg_read(bd71837, BD71837_REG_REV);
> +	if (ret < 0) {

Is 0 return a successful read?  I suggest that it isn't.

> +		dev_err(&i2c->dev, "Read BD71837_REG_DEVICE failed\n");
> +		goto err_out;
> +	}
> +
> +	ret = devm_regmap_add_irq_chip(&i2c->dev, bd71837->regmap,
> +				       bd71837->chip_irq, IRQF_ONESHOT, 0,
> +				       &bd71837_irq_chip, &bd71837->irq_data);
> +	if (ret < 0) {

Is a >0 return valid?  If not, perhaps "if (ret)" would be better.

> +		dev_err(&i2c->dev, "Failed to add irq_chip\n");
> +		goto err_out;
> +	}
> +
> +	ret = regmap_update_bits(bd71837->regmap,
> +				 BD71837_REG_PWRONCONFIG0,
> +				 BD718XX_PWRBTN_PRESS_DURATION_MASK,
> +				 BD718XX_PWRBTN_SHORT_PRESS_10MS);
> +	if (ret < 0) {

As above.

> +		dev_err(&i2c->dev, "Failed to configure button short press timeout\n");
> +		goto err_out;
> +	}
> +
> +	/*
> +	 * According to BD71847 datasheet the HW default for long press
> +	 * detection is 10ms. So lets change it to 10 sec so we can actually
> +	 * get the short push and allow gracefull shut down
> +	 */

I don't think this comment is necessary.

If anything it only needs to say "Configure long press to 10 seconds".

And if you do that, please add one for short press too.

> +	ret = regmap_update_bits(bd71837->regmap,
> +				 BD71837_REG_PWRONCONFIG1,
> +				 BD718XX_PWRBTN_PRESS_DURATION_MASK,
> +				 BD718XX_PWRBTN_LONG_PRESS_10S);
> +
> +	if (ret < 0) {
> +		dev_err(&i2c->dev, "Failed to configure button long press timeout\n");
> +		goto err_out;
> +	}
> +
> +	btns[0].irq = regmap_irq_get_virq(bd71837->irq_data,
> +					  BD71837_INT_PWRBTN_S);
> +
> +	if (btns[0].irq < 0) {
> +		ret = btns[0].irq;
> +		dev_err(&i2c->dev, "Failed to get the IRQ\n");
> +		goto err_out;

No unwinding to be done, just return directly and save yourself an
superflouous goto.

> +	}
> +
> +	ret = devm_mfd_add_devices(bd71837->dev, PLATFORM_DEVID_AUTO,
> +				   bd71837_mfd_cells,
> +				   ARRAY_SIZE(bd71837_mfd_cells), NULL, 0,
> +				   regmap_irq_get_domain(bd71837->irq_data));
> +	if (ret)
> +		dev_err(&i2c->dev, "Failed to create subdevices\n");
> +err_out:
> +
> +	return ret;
> +}
> +
> +static const struct i2c_device_id bd71837_i2c_id[] = {
> +	{ .name = "bd71837", },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(i2c, bd71837_i2c_id);

You shouldn't need this table anymore.

See da10c06a044b ("i2c: Make I2C ID tables non-mandatory for DT'ed devices")

> +static struct i2c_driver bd71837_i2c_driver = {
> +	.driver = {
> +		.name = "bd71837-mfd",

And "MFD" isn't really a thing.  It's more common to just mention the
board name, or something like 'rohm-bd7183'.

> +		.of_match_table = bd71837_of_match,
> +	},
> +	.probe = bd71837_i2c_probe,
> +	.id_table = bd71837_i2c_id,
> +};
> +
> +static int __init bd71837_i2c_init(void)
> +{
> +	return i2c_add_driver(&bd71837_i2c_driver);
> +}
> +/*
> + * init early so consumer devices can complete system boot
> + */

This is a single line commit.  Please use the correct format.

  /* Single line comment */

> +subsys_initcall(bd71837_i2c_init);
> +
> +static void __exit bd71837_i2c_exit(void)
> +{
> +	i2c_del_driver(&bd71837_i2c_driver);
> +}
> +module_exit(bd71837_i2c_exit);
> +
> +MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
> +MODULE_DESCRIPTION("BD71837 chip multi-function driver");

'PMIC' or 'Power Management IC' rather than MFD.

> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/mfd/bd71837.h b/include/linux/mfd/bd71837.h
> new file mode 100644
> index 000000000000..10b0dfe90f27
> --- /dev/null
> +++ b/include/linux/mfd/bd71837.h
> @@ -0,0 +1,391 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */

I thought these were meant to use C++ (//) comments?

> +/* Copyright (C) 2018 ROHM Semiconductors */
> +
> +/*
> + * ROHM BD71837MWV header file
> + */

If you prefix the mentions of (BD,bd)71837 with (ROHM,rohm) then this
comment becomes redundant and you can remove it.

> +#ifndef __LINUX_MFD_BD71837_H__
> +#define __LINUX_MFD_BD71837_H__
> +
> +#include <linux/regmap.h>
> +
> +enum {
> +	BD71837_BUCK1	=	0,
> +	BD71837_BUCK2,
> +	BD71837_BUCK3,
> +	BD71837_BUCK4,
> +	BD71837_BUCK5,
> +	BD71837_BUCK6,
> +	BD71837_BUCK7,
> +	BD71837_BUCK8,
> +	BD71837_LDO1,
> +	BD71837_LDO2,
> +	BD71837_LDO3,
> +	BD71837_LDO4,
> +	BD71837_LDO5,
> +	BD71837_LDO6,
> +	BD71837_LDO7,
> +	BD71837_REGULATOR_CNT,
> +};
> +
> +#define BD71837_BUCK1_VOLTAGE_NUM	0x40
> +#define BD71837_BUCK2_VOLTAGE_NUM	0x40
> +#define BD71837_BUCK3_VOLTAGE_NUM	0x40
> +#define BD71837_BUCK4_VOLTAGE_NUM	0x40
> +
> +#define BD71837_BUCK5_VOLTAGE_NUM	0x08
> +#define BD71837_BUCK6_VOLTAGE_NUM	0x04
> +#define BD71837_BUCK7_VOLTAGE_NUM	0x08
> +#define BD71837_BUCK8_VOLTAGE_NUM	0x40
> +
> +#define BD71837_LDO1_VOLTAGE_NUM	0x04
> +#define BD71837_LDO2_VOLTAGE_NUM	0x02
> +#define BD71837_LDO3_VOLTAGE_NUM	0x10
> +#define BD71837_LDO4_VOLTAGE_NUM	0x10
> +#define BD71837_LDO5_VOLTAGE_NUM	0x10
> +#define BD71837_LDO6_VOLTAGE_NUM	0x10
> +#define BD71837_LDO7_VOLTAGE_NUM	0x10
> +
> +enum {
> +	BD71837_REG_REV                = 0x00,
> +	BD71837_REG_SWRESET            = 0x01,
> +	BD71837_REG_I2C_DEV            = 0x02,
> +	BD71837_REG_PWRCTRL0           = 0x03,
> +	BD71837_REG_PWRCTRL1           = 0x04,
> +	BD71837_REG_BUCK1_CTRL         = 0x05,
> +	BD71837_REG_BUCK2_CTRL         = 0x06,
> +	BD71837_REG_BUCK3_CTRL         = 0x07,
> +	BD71837_REG_BUCK4_CTRL         = 0x08,
> +	BD71837_REG_BUCK5_CTRL         = 0x09,
> +	BD71837_REG_BUCK6_CTRL         = 0x0A,
> +	BD71837_REG_BUCK7_CTRL         = 0x0B,
> +	BD71837_REG_BUCK8_CTRL         = 0x0C,
> +	BD71837_REG_BUCK1_VOLT_RUN     = 0x0D,
> +	BD71837_REG_BUCK1_VOLT_IDLE    = 0x0E,
> +	BD71837_REG_BUCK1_VOLT_SUSP    = 0x0F,
> +	BD71837_REG_BUCK2_VOLT_RUN     = 0x10,
> +	BD71837_REG_BUCK2_VOLT_IDLE    = 0x11,
> +	BD71837_REG_BUCK3_VOLT_RUN     = 0x12,
> +	BD71837_REG_BUCK4_VOLT_RUN     = 0x13,
> +	BD71837_REG_BUCK5_VOLT         = 0x14,
> +	BD71837_REG_BUCK6_VOLT         = 0x15,
> +	BD71837_REG_BUCK7_VOLT         = 0x16,
> +	BD71837_REG_BUCK8_VOLT         = 0x17,
> +	BD71837_REG_LDO1_VOLT          = 0x18,
> +	BD71837_REG_LDO2_VOLT          = 0x19,
> +	BD71837_REG_LDO3_VOLT          = 0x1A,
> +	BD71837_REG_LDO4_VOLT          = 0x1B,
> +	BD71837_REG_LDO5_VOLT          = 0x1C,
> +	BD71837_REG_LDO6_VOLT          = 0x1D,
> +	BD71837_REG_LDO7_VOLT          = 0x1E,
> +	BD71837_REG_TRANS_COND0        = 0x1F,
> +	BD71837_REG_TRANS_COND1        = 0x20,
> +	BD71837_REG_VRFAULTEN          = 0x21,
> +	BD71837_REG_MVRFLTMASK0        = 0x22,
> +	BD71837_REG_MVRFLTMASK1        = 0x23,
> +	BD71837_REG_MVRFLTMASK2        = 0x24,
> +	BD71837_REG_RCVCFG             = 0x25,
> +	BD71837_REG_RCVNUM             = 0x26,
> +	BD71837_REG_PWRONCONFIG0       = 0x27,
> +	BD71837_REG_PWRONCONFIG1       = 0x28,
> +	BD71837_REG_RESETSRC           = 0x29,
> +	BD71837_REG_MIRQ               = 0x2A,
> +	BD71837_REG_IRQ                = 0x2B,
> +	BD71837_REG_IN_MON             = 0x2C,
> +	BD71837_REG_POW_STATE          = 0x2D,
> +	BD71837_REG_OUT32K             = 0x2E,
> +	BD71837_REG_REGLOCK            = 0x2F,
> +	BD71837_REG_OTPVER             = 0xFF,
> +	BD71837_MAX_REGISTER           = 0x100,
> +};
> +
> +#define REGLOCK_PWRSEQ	0x1
> +#define REGLOCK_VREG	0x10
> +
> +/* Generic BUCK control masks */
> +#define BD71837_BUCK_SEL	0x02
> +#define BD71837_BUCK_EN		0x01
> +#define BD71837_BUCK_RUN_ON	0x04
> +
> +/* Generic LDO masks */
> +#define BD71837_LDO_SEL		0x80
> +#define BD71837_LDO_EN		0x40
> +
> +/* BD71837 BUCK ramp rate CTRL reg bits */
> +#define BUCK_RAMPRATE_MASK	0xC0
> +#define BUCK_RAMPRATE_10P00MV	0x0
> +#define BUCK_RAMPRATE_5P00MV	0x1
> +#define BUCK_RAMPRATE_2P50MV	0x2
> +#define BUCK_RAMPRATE_1P25MV	0x3
> +
> +/* BD71837_REG_BUCK1_VOLT_RUN bits */
> +#define BUCK1_RUN_MASK		0x3F
> +#define BUCK1_RUN_DEFAULT	0x14
> +
> +/* BD71837_REG_BUCK1_VOLT_SUSP bits */
> +#define BUCK1_SUSP_MASK		0x3F
> +#define BUCK1_SUSP_DEFAULT	0x14
> +
> +/* BD71837_REG_BUCK1_VOLT_IDLE bits */
> +#define BUCK1_IDLE_MASK		0x3F
> +#define BUCK1_IDLE_DEFAULT	0x14
> +
> +/* BD71837_REG_BUCK2_VOLT_RUN bits */
> +#define BUCK2_RUN_MASK		0x3F
> +#define BUCK2_RUN_DEFAULT	0x1E
> +
> +/* BD71837_REG_BUCK2_VOLT_IDLE bits */
> +#define BUCK2_IDLE_MASK		0x3F
> +#define BUCK2_IDLE_DEFAULT	0x14
> +
> +/* BD71837_REG_BUCK3_VOLT_RUN bits */
> +#define BUCK3_RUN_MASK		0x3F
> +#define BUCK3_RUN_DEFAULT	0x1E
> +
> +/* BD71837_REG_BUCK4_VOLT_RUN bits */
> +#define BUCK4_RUN_MASK		0x3F
> +#define BUCK4_RUN_DEFAULT	0x1E
> +
> +/* BD71837_REG_BUCK5_VOLT bits */
> +#define BUCK5_MASK		0x07
> +#define BUCK5_DEFAULT		0x02
> +
> +/* BD71837_REG_BUCK6_VOLT bits */
> +#define BUCK6_MASK		0x03
> +#define BUCK6_DEFAULT		0x03
> +
> +/* BD71837_REG_BUCK7_VOLT bits */
> +#define BUCK7_MASK		0x07
> +#define BUCK7_DEFAULT		0x03
> +
> +/* BD71837_REG_BUCK8_VOLT bits */
> +#define BUCK8_MASK		0x3F
> +#define BUCK8_DEFAULT		0x1E
> +
> +/* BD71837_REG_IRQ bits */
> +#define IRQ_SWRST		0x40
> +#define IRQ_PWRON_S		0x20
> +#define IRQ_PWRON_L		0x10
> +#define IRQ_PWRON		0x08
> +#define IRQ_WDOG		0x04
> +#define IRQ_ON_REQ		0x02
> +#define IRQ_STBY_REQ		0x01
> +
> +/* BD71837_REG_OUT32K bits */
> +#define BD71837_OUT32K_EN	0x01
> +
> +/* BD71837 gated clock rate */
> +#define BD71837_CLK_RATE 32768
> +
> +/* BD71837 irqs */
> +enum {
> +	BD71837_INT_STBY_REQ,
> +	BD71837_INT_ON_REQ,
> +	BD71837_INT_WDOG,
> +	BD71837_INT_PWRBTN,
> +	BD71837_INT_PWRBTN_L,
> +	BD71837_INT_PWRBTN_S,
> +	BD71837_INT_SWRST
> +};
> +
> +/* BD71837 interrupt masks */
> +#define BD71837_INT_SWRST_MASK		0x40
> +#define BD71837_INT_PWRBTN_S_MASK	0x20
> +#define BD71837_INT_PWRBTN_L_MASK	0x10
> +#define BD71837_INT_PWRBTN_MASK		0x8
> +#define BD71837_INT_WDOG_MASK		0x4
> +#define BD71837_INT_ON_REQ_MASK		0x2
> +#define BD71837_INT_STBY_REQ_MASK	0x1
> +
> +/* BD71837_REG_LDO1_VOLT bits */
> +#define LDO1_MASK		0x03
> +
> +/* BD71837_REG_LDO1_VOLT bits */
> +#define LDO2_MASK		0x20
> +
> +/* BD71837_REG_LDO3_VOLT bits */
> +#define LDO3_MASK		0x0F
> +
> +/* BD71837_REG_LDO4_VOLT bits */
> +#define LDO4_MASK		0x0F
> +
> +/* BD71837_REG_LDO5_VOLT bits */
> +#define LDO5_MASK		0x0F
> +
> +/* BD71837_REG_LDO6_VOLT bits */
> +#define LDO6_MASK		0x0F
> +
> +/* BD71837_REG_LDO7_VOLT bits */
> +#define LDO7_MASK		0x0F
> +
> +/* Register write induced reset settings */
> +
> +/* Even though the bit zero is not SWRESET type we still want to write zero
> + * to it when changing type. Bit zero is 'SWRESET' trigger bit and if we
> + * write 1 to it we will trigger the action. So always write 0 to it when
> + * changning SWRESET action - no matter what we read from it.
> + */

Please use the correct format for multi-line comments.

Hint: The first line should be empty.

> +#define BD71837_SWRESET_TYPE_MASK 7
> +#define BD71837_SWRESET_TYPE_DISABLED 0
> +#define BD71837_SWRESET_TYPE_COLD 4
> +#define BD71837_SWRESET_TYPE_WARM 6
> +
> +#define BD71837_SWRESET_RESET_MASK 1
> +#define BD71837_SWRESET_RESET 1
> +
> +/* Poweroff state transition conditions */
> +
> +#define BD718XX_ON_REQ_POWEROFF_MASK 1
> +#define BD718XX_SWRESET_POWEROFF_MASK 2
> +#define BD718XX_WDOG_POWEROFF_MASK 4
> +#define BD718XX_KEY_L_POWEROFF_MASK 8
> +
> +#define BD718XX_POWOFF_TO_SNVS 0
> +#define BD718XX_POWOFF_TO_RDY 0xF

Please align each of the values with tabs.

> +#define BD718XX_POWOFF_TIME_MASK 0xF0
> +enum {
> +	BD718XX_POWOFF_TIME_5MS = 0,
> +	BD718XX_POWOFF_TIME_10MS,
> +	BD718XX_POWOFF_TIME_15MS,
> +	BD718XX_POWOFF_TIME_20MS,
> +	BD718XX_POWOFF_TIME_25MS,
> +	BD718XX_POWOFF_TIME_30MS,
> +	BD718XX_POWOFF_TIME_35MS,
> +	BD718XX_POWOFF_TIME_40MS,
> +	BD718XX_POWOFF_TIME_45MS,
> +	BD718XX_POWOFF_TIME_50MS,
> +	BD718XX_POWOFF_TIME_75MS,
> +	BD718XX_POWOFF_TIME_100MS,
> +	BD718XX_POWOFF_TIME_250MS,
> +	BD718XX_POWOFF_TIME_500MS,
> +	BD718XX_POWOFF_TIME_750MS,
> +	BD718XX_POWOFF_TIME_1500MS
> +};
> +
> +/* Poweron sequence state transition conditions */
> +
> +#define BD718XX_RDY_TO_SNVS_MASK 0xF
> +#define BD718XX_SNVS_TO_RUN_MASK 0xF0
> +
> +#define BD718XX_PWR_TRIG_KEY_L 1
> +#define BD718XX_PWR_TRIG_KEY_S 2
> +#define BD718XX_PWR_TRIG_PMIC_ON 4
> +#define BD718XX_PWR_TRIG_VSYS_UVLO 8
> +#define BD718XX_RDY_TO_SNVS_SIFT 0
> +#define BD718XX_SNVS_TO_RUN_SIFT 4

As above.

> +
> +

No need for 2 '\n'.

> +#define BD718XX_PWRBTN_PRESS_DURATION_MASK 0xF
> +
> +/* Timeout value for detecting short press */
> +
> +enum {
> +	BD718XX_PWRBTN_SHORT_PRESS_10MS = 0,
> +	BD718XX_PWRBTN_SHORT_PRESS_500MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_1000MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_1500MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_2000MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_2500MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_3000MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_3500MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_4000MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_4500MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_5000MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_5500MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_6000MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_6500MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_7000MS,
> +	BD718XX_PWRBTN_SHORT_PRESS_7500MS
> +};
> +
> +/* Timeout value for detecting LONG press */
> +
> +enum {
> +	BD718XX_PWRBTN_LONG_PRESS_10MS = 0,
> +	BD718XX_PWRBTN_LONG_PRESS_1S,
> +	BD718XX_PWRBTN_LONG_PRESS_2S,
> +	BD718XX_PWRBTN_LONG_PRESS_3S,
> +	BD718XX_PWRBTN_LONG_PRESS_4S,
> +	BD718XX_PWRBTN_LONG_PRESS_5S,
> +	BD718XX_PWRBTN_LONG_PRESS_6S,
> +	BD718XX_PWRBTN_LONG_PRESS_7S,
> +	BD718XX_PWRBTN_LONG_PRESS_8S,
> +	BD718XX_PWRBTN_LONG_PRESS_9S,
> +	BD718XX_PWRBTN_LONG_PRESS_10S,
> +	BD718XX_PWRBTN_LONG_PRESS_11S,
> +	BD718XX_PWRBTN_LONG_PRESS_12S,
> +	BD718XX_PWRBTN_LONG_PRESS_13S,
> +	BD718XX_PWRBTN_LONG_PRESS_14S,
> +	BD718XX_PWRBTN_LONG_PRESS_15S
> +};
> +
> +
> +

Certainly no need for 3 '\n'.

> +struct bd71837;

Why is this necessary?

> +struct bd71837_pmic;
> +struct bd71837_clk;
> +struct bd718xx_pwrkey;

Where are these forward declared from?

> +/*
> + * Board platform data may be used to initialize regulators.
> + */
> +
> +struct bd71837_board {
> +	struct regulator_init_data *init_data[BD71837_REGULATOR_CNT];
> +	int	gpio_intr;
> +};

Where is this populated?

> +struct bd71837 {
> +	struct device *dev;
> +	struct i2c_client *i2c_client;
> +	struct regmap *regmap;
> +	unsigned long int id;
> +
> +	int chip_irq;
> +	struct regmap_irq_chip_data *irq_data;
> +
> +	struct bd71837_pmic *pmic;
> +	struct bd71837_clk *clk;
> +	struct bd718xx_pwrkey *pwrkey;
> +};
> +
> +/*
> + * bd71837 sub-driver chip access routines
> + */
> +
> +static inline int bd71837_reg_read(struct bd71837 *bd71837, u8 reg)
> +{
> +	int r, val;
> +
> +	r = regmap_read(bd71837->regmap, reg, &val);
> +	if (r < 0)
> +		return r;
> +	return val;
> +}
> +
> +static inline int bd71837_reg_write(struct bd71837 *bd71837, u8 reg,
> +				    unsigned int val)
> +{
> +	return regmap_write(bd71837->regmap, reg, val);
> +}
> +
> +static inline int bd71837_set_bits(struct bd71837 *bd71837, u8 reg, u8 mask)
> +{
> +	return regmap_update_bits(bd71837->regmap, reg, mask, mask);
> +}
> +
> +static inline int bd71837_clear_bits(struct bd71837 *bd71837, u8 reg,
> +				     u8 mask)
> +{
> +	return regmap_update_bits(bd71837->regmap, reg, mask, 0);
> +}
> +
> +static inline int bd71837_update_bits(struct bd71837 *bd71837, u8 reg,
> +				      u8 mask, u8 val)
> +{
> +	return regmap_update_bits(bd71837->regmap, reg, mask, val);
> +}

Please don't abstract APIs for no reason.

Use the regmap_* API directly instead.

> +#endif /* __LINUX_MFD_BD71837_H__ */

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog