Re: [PATCH v5 1/7] mfd: Add support for DA9150 combined charger & fuel-gauge device

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

On Mon, 19 Jan 2015, Opensource [Adam Thomson] wrote:

> On January 19, 2015 11:34, Lee Jones wrote:
> 
> > On Mon, 22 Dec 2014, Adam Thomson wrote:
> > 
> > > DA9150 is a combined Charger and Fuel-Gauge IC, with additional
> > > GPIO and GPADC functionality.
> > >
> > > Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
> > > ---
> > >  drivers/mfd/Kconfig                  |   12 +
> > >  drivers/mfd/Makefile                 |    2 +-
> > >  drivers/mfd/da9150-core.c            |  413 ++++++++++++
> > >  include/linux/mfd/da9150/core.h      |   68 ++
> > >  include/linux/mfd/da9150/registers.h | 1155
> > ++++++++++++++++++++++++++++++++++
> > >  5 files changed, 1649 insertions(+), 1 deletion(-)
> > >  create mode 100644 drivers/mfd/da9150-core.c
> > >  create mode 100644 include/linux/mfd/da9150/core.h
> > >  create mode 100644 include/linux/mfd/da9150/registers.h
> > >
> > > diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> > > index 2e6b731..56e80d2 100644
> > > --- a/drivers/mfd/Kconfig
> > > +++ b/drivers/mfd/Kconfig
> > > @@ -195,6 +195,18 @@ config MFD_DA9063
> > >  	  Additional drivers must be enabled in order to use the functionality
> > >  	  of the device.
> > >
> > > +config MFD_DA9150
> > > +	tristate "Dialog Semiconductor DA9150 Charger Fuel-Gauge chip"
> > > +	depends on I2C=y
> > > +	select MFD_CORE
> > > +	select REGMAP_I2C
> > > +	select REGMAP_IRQ
> > > +	help
> > > +	  This adds support for the DA9150 integrated charger and fuel-gauge
> > > +	  chip. This driver provides common support for accessing the device.
> > > +	  Additional drivers must be enabled in order to use the specific
> > > +	  features of the device.
> > > +
> > >  config MFD_DLN2
> > >  	tristate "Diolan DLN2 support"
> > >  	select MFD_CORE
> > > diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> > > index 53467e2..f06f4c6 100644
> > > --- a/drivers/mfd/Makefile
> > > +++ b/drivers/mfd/Makefile
> > > @@ -113,7 +113,7 @@ obj-$(CONFIG_MFD_DA9055)	+= da9055.o
> > >
> > >  da9063-objs			:= da9063-core.o da9063-irq.o da9063-i2c.o
> > >  obj-$(CONFIG_MFD_DA9063)	+= da9063.o
> > > -
> > > +obj-$(CONFIG_MFD_DA9150)	+= da9150-core.o
> > >  obj-$(CONFIG_MFD_MAX14577)	+= max14577.o
> > >  obj-$(CONFIG_MFD_MAX77686)	+= max77686.o
> > >  obj-$(CONFIG_MFD_MAX77693)	+= max77693.o
> > > diff --git a/drivers/mfd/da9150-core.c b/drivers/mfd/da9150-core.c
> > > new file mode 100644
> > > index 0000000..4d757b9
> > > --- /dev/null
> > > +++ b/drivers/mfd/da9150-core.c
> > > @@ -0,0 +1,413 @@
> > > +/*
> > > + * DA9150 Core MFD Driver
> > > + *
> > > + * Copyright (c) 2014 Dialog Semiconductor
> > > + *
> > > + * Author: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
> > > + *
> > > + * This program is free software; you can redistribute  it and/or modify it
> > > + * under  the terms of  the GNU General  Public License as published by the
> > > + * Free Software Foundation;  either version 2 of the  License, or (at your
> > > + * option) any later version.
> > > + */
> > 
> > [...]
> > 
> > > +u8 da9150_reg_read(struct da9150 *da9150, u16 reg)
> > > +{
> > > +	int val, ret;
> > > +
> > > +	ret = regmap_read(da9150->regmap, reg, &val);
> > > +	if (ret)
> > > +		dev_err(da9150->dev, "Failed to read from reg 0x%x: %d\n",
> > > +			reg, ret);
> > > +
> > > +	return (u8) val;
> > > +}
> > > +EXPORT_SYMBOL_GPL(da9150_reg_read);
> > > +
> > > +void da9150_reg_write(struct da9150 *da9150, u16 reg, u8 val)
> > > +{
> > > +	int ret;
> > > +
> > > +	ret = regmap_write(da9150->regmap, reg, val);
> > > +	if (ret)
> > > +		dev_err(da9150->dev, "Failed to write to reg 0x%x: %d\n",
> > > +			reg, ret);
> > > +}
> > > +EXPORT_SYMBOL_GPL(da9150_reg_write);
> > > +
> > > +void da9150_set_bits(struct da9150 *da9150, u16 reg, u8 mask, u8 val)
> > > +{
> > > +	int ret;
> > > +
> > > +	ret = regmap_update_bits(da9150->regmap, reg, mask, val);
> > > +	if (ret)
> > > +		dev_err(da9150->dev, "Failed to set bits in reg 0x%x: %d\n",
> > > +			reg, ret);
> > > +}
> > > +EXPORT_SYMBOL_GPL(da9150_set_bits);
> > > +
> > > +void da9150_bulk_read(struct da9150 *da9150, u16 reg, int count, u8 *buf)
> > > +{
> > > +	int ret;
> > > +
> > > +	ret = regmap_bulk_read(da9150->regmap, reg, buf, count);
> > > +	if (ret)
> > > +		dev_err(da9150->dev, "Failed to bulk read from reg 0x%x: %d\n",
> > > +			reg, ret);
> > > +}
> > > +EXPORT_SYMBOL_GPL(da9150_bulk_read);
> > > +
> > > +void da9150_bulk_write(struct da9150 *da9150, u16 reg, int count, const u8
> > *buf)
> > > +{
> > > +	int ret;
> > > +
> > > +	ret = regmap_raw_write(da9150->regmap, reg, buf, count);
> > > +	if (ret)
> > > +		dev_err(da9150->dev, "Failed to bulk write to reg 0x%x %d\n",
> > > +			reg, ret);
> > > +}
> > > +EXPORT_SYMBOL_GPL(da9150_bulk_write);
> > 
> > I've never been a fan of this type of aggregation.  Can you explain to
> > me what the point of them is?
> 
> I refer you back to our previous discussion some time back:
> 
> https://lkml.org/lkml/2014/9/9/284
> 
> 'The reason for these is because future patches to add additional functionality
> will introduce I2C access functions which do not use regmap and access the
> device via a separate I2C address for this purpose. I will need to provide
> access functions for that, and so having a common style of I2C access makes
> sense for this driver. Means any access just needs to provide the MFD private
> data, and the relevant functions take care of the rest. I think this is cleaner
> in this instance.'

Well at least I'm consistent.

For my own reference:
  Acked-by: Lee Jones <lee.jones@linaro.org>

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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