Re: [PATCH v5 08/16] mfd: bd71828: Support ROHM BD72720

[Matti Vaittinen <mazziesaccount@gmail.com>]

On 26/11/2025 16:28, Lee Jones wrote:
> On Thu, 20 Nov 2025, Matti Vaittinen wrote:
> 
>> From: Matti Vaittinen <mazziesaccount@gmail.com>
>>
>> The ROHM BD72720 is a power management IC which continues the BD71828
>> family of PMICs. Similarly to the BD71815 and BD71828, the BD72720
>> integrates regulators, charger, RTC, clock gate and GPIOs.
>>
>> The main difference to the earlier PMICs is that the BD72720 has two
>> different I2C slave addresses. In addition to the registers behind the
>> 'main I2C address', most of the charger (and to some extent LED) control
>> is done via registers behind a 'secondary I2C slave address', 0x4c.
>>
>> Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
>>
>> ---
>> Revision history:
>>   v2 =>:
>>   - no changes
>>
>>   RFCv1 => v2: (Mostly addressed comments from Lee and Andreas)
>>   - Use stacked regmaps to avoid platform data and the tango with
>>     multiple regmaps in the power-supply driver
>>   - Use regmap_reg_range()
>>   - make it clear bd72720_irq_type_base is an array
>>   - tab-out definitions in the bd72720 header
>>   - minor styling
>>
>> Note: This patch depends on the series: "power: supply: add charger for
>> BD71828" by Andreas:
>> https://lore.kernel.org/all/20250918-bd71828-charger-v5-0-851164839c28@kemnade.info/
>>
>> There are some new variants being planned. Most notably, the BD73900
>> should be almost identical to the BD72720 - for everything else except
>> the charger block.
>> ---
>>   drivers/mfd/Kconfig              |  18 +-
>>   drivers/mfd/rohm-bd71828.c       | 488 +++++++++++++++++++++++-
>>   include/linux/mfd/rohm-bd72720.h | 634 +++++++++++++++++++++++++++++++
>>   include/linux/mfd/rohm-generic.h |   1 +
>>   4 files changed, 1126 insertions(+), 15 deletions(-)
>>   create mode 100644 include/linux/mfd/rohm-bd72720.h

// snip

>> diff --git a/drivers/mfd/rohm-bd71828.c b/drivers/mfd/rohm-bd71828.c
>> index 2a43005b67ee..2e546aa60ffd 100644
>> --- a/drivers/mfd/rohm-bd71828.c
>> +++ b/drivers/mfd/rohm-bd71828.c
>> @@ -2,7 +2,7 @@
>>   //
>>   // Copyright (C) 2019 ROHM Semiconductors
>>   //
>> -// ROHM BD71828/BD71815 PMIC driver
>> +// ROHM BD718[15/28/79] and BD72720 PMIC driver
> 
> Looks like this header format slipped in.
> 
> I would appreciate a follow-up patch to change it to standard C
> multi-line format (except the SPDX line).

Sure.

// snip

>>   
>> +static int regmap_write_wrapper(void *context, unsigned int reg, unsigned int val)
>> +{
>> +	struct bd72720_regmaps *maps = context;
>> +
>> +	if (reg < 0x100)
> 
> Define this to something human readable please.
> 
> Some kind of PAGE or BOUNDARY.  Perhaps something better.

I will use 'BD72720_SECONDARY_I2C_REG_OFFSET'. A tad long, but it's not 
used on a long lines.

> 
>> +		return regmap_write(maps->map1_4b, reg, val);
>> +
>> +	reg = BD72720_REG_UNWRAP(reg);
>> +
>> +	return regmap_write(maps->map2_4c, reg, val);
>> +}

// snip

> 
>> +		return (struct regmap *)secondary_i2c;
> 
> *shudders* -- that's a hack, right!
> 
> /me does some grepping around ...
> 
> Shouldn't this be:
> 
> 		return ERR_CAST(secondary_i2c);

I didn't know about the ERR_CAST(). Thanks for going the extra mile and 
looking

> 
>> +	}

//snip

>> diff --git a/include/linux/mfd/rohm-bd72720.h b/include/linux/mfd/rohm-bd72720.h
>> new file mode 100644
>> index 000000000000..42fcf8f81b2f
>> --- /dev/null
>> +++ b/include/linux/mfd/rohm-bd72720.h
>> @@ -0,0 +1,634 @@
>> +/* SPDX-License-Identifier: GPL-2.0-or-later */
>> +/*
>> + * Copyright 2024 ROHM Semiconductors.
> 
> Still out of date.

Ah. Indeed. Thanks.

>> + * Author: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
>> + */
>> +
// snip

>> +
>> +/* BD72720 interrupts */
>> +#define BD72720_INT_LONGPUSH_MASK	BIT(0)
>> +#define BD72720_INT_MIDPUSH_MASK	BIT(1)
>> +#define BD72720_INT_SHORTPUSH_MASK	BIT(2)
>> +#define BD72720_INT_PUSH_MASK		BIT(3)
>> +#define BD72720_INT_HALL_DET_MASK	BIT(4)
>> +#define BD72720_INT_HALL_TGL_MASK	BIT(5)
>> +#define BD72720_INT_WDOG_MASK		BIT(6)
>> +#define BD72720_INT_SWRESET_MASK	BIT(7)
>> +#define BD72720_INT_SEQ_DONE_MASK	BIT(0)
>> +#define BD72720_INT_PGFAULT_MASK	BIT(4)
>> +#define BD72720_INT_BUCK1_DVS_MASK	BIT(0)
>> +#define BD72720_INT_BUCK2_DVS_MASK	BIT(1)
>> +#define BD72720_INT_BUCK3_DVS_MASK	BIT(2)
>> +#define BD72720_INT_BUCK4_DVS_MASK	BIT(3)
>> +#define BD72720_INT_BUCK5_DVS_MASK	BIT(4)
>> +#define BD72720_INT_BUCK6_DVS_MASK	BIT(5)
>> +#define BD72720_INT_BUCK7_DVS_MASK	BIT(6)
>> +#define BD72720_INT_BUCK8_DVS_MASK	BIT(7)
>> +#define BD72720_INT_BUCK9_DVS_MASK	BIT(0)
>> +#define BD72720_INT_BUCK10_DVS_MASK	BIT(1)
>> +#define BD72720_INT_LDO1_DVS_MASK	BIT(4)
>> +#define BD72720_INT_LDO2_DVS_MASK	BIT(5)
>> +#define BD72720_INT_LDO3_DVS_MASK	BIT(6)
>> +#define BD72720_INT_LDO4_DVS_MASK	BIT(7)
>> +#define BD72720_INT_VBUS_RMV_MASK	BIT(0)
>> +#define BD72720_INT_VBUS_DET_MASK	BIT(1)
>> +#define BD72720_INT_VBUS_MON_RES_MASK	BIT(2)
>> +#define BD72720_INT_VBUS_MON_DET_MASK	BIT(3)
>> +#define BD72720_INT_VSYS_MON_RES_MASK	BIT(0)
>> +#define BD72720_INT_VSYS_MON_DET_MASK	BIT(1)
>> +#define BD72720_INT_VSYS_UV_RES_MASK	BIT(2)
>> +#define BD72720_INT_VSYS_UV_DET_MASK	BIT(3)
>> +#define BD72720_INT_VSYS_LO_RES_MASK	BIT(4)
>> +#define BD72720_INT_VSYS_LO_DET_MASK	BIT(5)
>> +#define BD72720_INT_VSYS_OV_RES_MASK	BIT(6)
>> +#define BD72720_INT_VSYS_OV_DET_MASK	BIT(7)
>> +#define BD72720_INT_BAT_ILIM_MASK	BIT(0)
>> +#define BD72720_INT_CHG_DONE_MASK	BIT(1)
>> +#define BD72720_INT_EXTEMP_TOUT_MASK	BIT(2)
>> +#define BD72720_INT_CHG_WDT_EXP_MASK	BIT(3)
>> +#define BD72720_INT_BAT_MNT_OUT_MASK	BIT(4)
>> +#define BD72720_INT_BAT_MNT_IN_MASK	BIT(5)
>> +#define BD72720_INT_CHG_TRNS_MASK	BIT(7)
>> +#define BD72720_INT_VBAT_MON_RES_MASK	BIT(0)
>> +#define BD72720_INT_VBAT_MON_DET_MASK	BIT(1)
>> +#define BD72720_INT_VBAT_SHT_RES_MASK	BIT(2)
>> +#define BD72720_INT_VBAT_SHT_DET_MASK	BIT(3)
>> +#define BD72720_INT_VBAT_LO_RES_MASK	BIT(4)
>> +#define BD72720_INT_VBAT_LO_DET_MASK	BIT(5)
>> +#define BD72720_INT_VBAT_OV_RES_MASK	BIT(6)
>> +#define BD72720_INT_VBAT_OV_DET_MASK	BIT(7)
>> +#define BD72720_INT_BAT_RMV_MASK	BIT(0)
>> +#define BD72720_INT_BAT_DET_MASK	BIT(1)
>> +#define BD72720_INT_DBAT_DET_MASK	BIT(2)
>> +#define BD72720_INT_BAT_TEMP_TRNS_MASK	BIT(3)
>> +#define BD72720_INT_LOBTMP_RES_MASK	BIT(4)
>> +#define BD72720_INT_LOBTMP_DET_MASK	BIT(5)
>> +#define BD72720_INT_OVBTMP_RES_MASK	BIT(6)
>> +#define BD72720_INT_OVBTMP_DET_MASK	BIT(7)
>> +#define BD72720_INT_OCUR1_RES_MASK	BIT(0)
>> +#define BD72720_INT_OCUR1_DET_MASK	BIT(1)
>> +#define BD72720_INT_OCUR2_RES_MASK	BIT(2)
>> +#define BD72720_INT_OCUR2_DET_MASK	BIT(3)
>> +#define BD72720_INT_OCUR3_RES_MASK	BIT(4)
>> +#define BD72720_INT_OCUR3_DET_MASK	BIT(5)
>> +#define BD72720_INT_CC_MON1_DET_MASK	BIT(0)
>> +#define BD72720_INT_CC_MON2_DET_MASK	BIT(1)
>> +#define BD72720_INT_CC_MON3_DET_MASK	BIT(2)
>> +#define BD72720_INT_GPIO1_IN_MASK	BIT(4)
>> +#define BD72720_INT_GPIO2_IN_MASK	BIT(5)
>> +#define BD72720_INT_VF125_RES_MASK	BIT(0)
>> +#define BD72720_INT_VF125_DET_MASK	BIT(1)
>> +#define BD72720_INT_VF_RES_MASK		BIT(2)
>> +#define BD72720_INT_VF_DET_MASK		BIT(3)
>> +#define BD72720_INT_RTC0_MASK		BIT(4)
>> +#define BD72720_INT_RTC1_MASK		BIT(5)
>> +#define BD72720_INT_RTC2_MASK		BIT(6)
> 
> I'd be able to sleep better if these all lined up.

Hm. I think they are when this is applied?

Thanks for the review! I agree with all the comments I didn't comment 
on. I'll prepare v6 fixing these :)

Yours,
	-- Matti

---
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland

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