diff mbox

[v4,2/6] mfd: axp20x: Split the driver into core and i2c bits

Message ID 1448336916-31212-3-git-send-email-wens@csie.org (mailing list archive)
State New, archived
Headers show

Commit Message

Chen-Yu Tsai Nov. 24, 2015, 3:48 a.m. UTC
The axp20x driver assumes the device is i2c based. This is not the
case with later chips, which use a proprietary 2 wire serial bus
by Allwinner called "Reduced Serial Bus".

This patch follows the example of mfd/wm831x and splits it into
an interface independent core, and an i2c specific glue layer.
MFD_AXP20X and the new MFD_AXP20X_I2C are changed to tristate
symbols, allowing the driver to be built as modules.

Included but unused header files are removed as well.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 drivers/mfd/Kconfig        |  14 +++--
 drivers/mfd/Makefile       |   1 +
 drivers/mfd/axp20x-i2c.c   | 127 +++++++++++++++++++++++++++++++++++++++++++++
 drivers/mfd/axp20x.c       | 108 +++++---------------------------------
 include/linux/mfd/axp20x.h |  33 +++++++++++-
 5 files changed, 183 insertions(+), 100 deletions(-)
 create mode 100644 drivers/mfd/axp20x-i2c.c

Comments

Andy Shevchenko Nov. 24, 2015, 9:37 a.m. UTC | #1
On Tue, Nov 24, 2015 at 5:48 AM, Chen-Yu Tsai <wens@csie.org> wrote:
> The axp20x driver assumes the device is i2c based. This is not the
> case with later chips, which use a proprietary 2 wire serial bus
> by Allwinner called "Reduced Serial Bus".
>
> This patch follows the example of mfd/wm831x and splits it into
> an interface independent core, and an i2c specific glue layer.
> MFD_AXP20X and the new MFD_AXP20X_I2C are changed to tristate
> symbols, allowing the driver to be built as modules.
>
> Included but unused header files are removed as well.
>
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
> ---
>  drivers/mfd/Kconfig        |  14 +++--
>  drivers/mfd/Makefile       |   1 +
>  drivers/mfd/axp20x-i2c.c   | 127 +++++++++++++++++++++++++++++++++++++++++++++
>  drivers/mfd/axp20x.c       | 108 +++++---------------------------------
>  include/linux/mfd/axp20x.h |  33 +++++++++++-
>  5 files changed, 183 insertions(+), 100 deletions(-)
>  create mode 100644 drivers/mfd/axp20x-i2c.c
>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 4d92df6ef9fe..804cd3dcce32 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -91,14 +91,18 @@ config MFD_BCM590XX
>           Support for the BCM590xx PMUs from Broadcom
>
>  config MFD_AXP20X
> -       bool "X-Powers AXP20X"
> +       tristate
>         select MFD_CORE
> -       select REGMAP_I2C
>         select REGMAP_IRQ
> -       depends on I2C=y
> +
> +config MFD_AXP20X_I2C
> +       tristate "X-Powers AXP series PMICs with I2C"
> +       select MFD_AXP20X
> +       select REGMAP_I2C
> +       depends on I2C
>         help
> -         If you say Y here you get support for the X-Powers AXP202, AXP209 and
> -         AXP288 power management IC (PMIC).
> +         If you say Y here you get support for the X-Powers AXP series power
> +         management ICs (PMICs) controlled with I2C.
>           This driver include only the core APIs. You have to select individual
>           components like regulators or the PEK (Power Enable Key) under the
>           corresponding menus.
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index a8b76b81b467..a6913007d667 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -107,6 +107,7 @@ obj-$(CONFIG_PMIC_DA9052)   += da9052-core.o
>  obj-$(CONFIG_MFD_DA9052_SPI)   += da9052-spi.o
>  obj-$(CONFIG_MFD_DA9052_I2C)   += da9052-i2c.o
>  obj-$(CONFIG_MFD_AXP20X)       += axp20x.o
> +obj-$(CONFIG_MFD_AXP20X_I2C)   += axp20x-i2c.o
>
>  obj-$(CONFIG_MFD_LP3943)       += lp3943.o
>  obj-$(CONFIG_MFD_LP8788)       += lp8788.o lp8788-irq.o
> diff --git a/drivers/mfd/axp20x-i2c.c b/drivers/mfd/axp20x-i2c.c
> new file mode 100644
> index 000000000000..75b247af2514
> --- /dev/null
> +++ b/drivers/mfd/axp20x-i2c.c
> @@ -0,0 +1,127 @@
> +/*
> + * axp20x-i2c.c - I2C driver for the X-Powers' Power Management ICs
> + *
> + * AXP20x typically comprises an adaptive USB-Compatible PWM charger, BUCK DC-DC
> + * converters, LDOs, multiple 12-bit ADCs of voltage, current and temperature
> + * as well as configurable GPIOs.
> + *
> + * This driver supports the I2C variants.
> + *
> + * Author: Carlo Caione <carlo@caione.org>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/err.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/mfd/axp20x.h>
> +#include <linux/of_device.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +
> +static const struct of_device_id axp20x_i2c_of_match[] = {
> +       { .compatible = "x-powers,axp152", .data = (void *) AXP152_ID },
> +       { .compatible = "x-powers,axp202", .data = (void *) AXP202_ID },
> +       { .compatible = "x-powers,axp209", .data = (void *) AXP209_ID },
> +       { .compatible = "x-powers,axp221", .data = (void *) AXP221_ID },
> +       { },
> +};
> +MODULE_DEVICE_TABLE(of, axp20x_i2c_of_match);
> +
> +/*
> + * This is useless for OF-enabled devices, but it is needed by I2C subsystem
> + */
> +static const struct i2c_device_id axp20x_i2c_id[] = {
> +       { },
> +};
> +MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);
> +
> +static const struct acpi_device_id axp20x_i2c_acpi_match[] = {
> +       {
> +               .id = "INT33F4",
> +               .driver_data = AXP288_ID,
> +       },
> +       { },
> +};
> +MODULE_DEVICE_TABLE(acpi, axp20x_i2c_acpi_match);
> +
> +static int axp20x_i2c_match_device(struct axp20x_dev *axp20x,
> +                                  struct device *dev)
> +{
> +       const struct acpi_device_id *acpi_id;
> +       const struct of_device_id *of_id;
> +
> +       if (dev->of_node) {

What about

if (…of_node) {
      const struct of_device_id *id;
…
} else if ACPI_COMPANION(…) {
      const struct acpi_device_id *id;
…
} else {
 return -ENODEV;
}

> +               of_id = of_match_device(axp20x_i2c_of_match, dev);
> +               if (!of_id) {
> +                       dev_err(dev, "Unable to match OF ID\n");
> +                       return -ENODEV;
> +               }
> +               axp20x->variant = (long) of_id->data;

Extra space after casting.

> +       } else {
> +               acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
> +               if (!acpi_id || !acpi_id->driver_data) {
> +                       dev_err(dev, "Unable to match ACPI ID and data\n");
> +                       return -ENODEV;
> +               }
> +               axp20x->variant = (long) acpi_id->driver_data;

Ditto.

> +       }
> +
> +       return axp20x_match_device(axp20x, dev);
> +}
> +
> +static int axp20x_i2c_probe(struct i2c_client *i2c,
> +                           const struct i2c_device_id *id)
> +{
> +       struct axp20x_dev *axp20x;
> +       int ret;
> +
> +       axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
> +       if (!axp20x)
> +               return -ENOMEM;
> +
> +       ret = axp20x_i2c_match_device(axp20x, &i2c->dev);
> +       if (ret)
> +               return ret;
> +
> +       axp20x->dev = &i2c->dev;
> +       axp20x->irq = i2c->irq;

If you move _match_device() here you will be able to drop away struct
device * parameter.

> +       dev_set_drvdata(axp20x->dev, axp20x);
> +
> +       axp20x->regmap = devm_regmap_init_i2c(i2c, axp20x->regmap_cfg);
> +       if (IS_ERR(axp20x->regmap)) {
> +               ret = PTR_ERR(axp20x->regmap);
> +               dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
> +               return ret;
> +       }
> +
> +       return axp20x_device_probe(axp20x);
> +}
> +
> +static int axp20x_i2c_remove(struct i2c_client *i2c)
> +{
> +       struct axp20x_dev *axp20x = i2c_get_clientdata(i2c);
> +
> +       return axp20x_device_remove(axp20x);
> +}
> +
> +static struct i2c_driver axp20x_i2c_driver = {
> +       .driver = {
> +               .name   = "axp20x",
> +               .of_match_table = of_match_ptr(axp20x_i2c_of_match),
> +               .acpi_match_table = ACPI_PTR(axp20x_i2c_acpi_match),
> +       },
> +       .probe          = axp20x_i2c_probe,
> +       .remove         = axp20x_i2c_remove,
> +       .id_table       = axp20x_i2c_id,
> +};
> +
> +module_i2c_driver(axp20x_i2c_driver);
> +
> +MODULE_DESCRIPTION("PMIC MFD I2C driver for AXP20X");
> +MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/mfd/axp20x.c b/drivers/mfd/axp20x.c
> index 9842199e2e6c..01f139856bf1 100644
> --- a/drivers/mfd/axp20x.c
> +++ b/drivers/mfd/axp20x.c
> @@ -5,6 +5,8 @@
>   * converters, LDOs, multiple 12-bit ADCs of voltage, current and temperature
>   * as well as configurable GPIOs.
>   *
> + * This file contains the interface independent core functions.
> + *
>   * Author: Carlo Caione <carlo@caione.org>
>   *
>   * This program is free software; you can redistribute it and/or modify
> @@ -13,18 +15,14 @@
>   */
>
>  #include <linux/err.h>
> -#include <linux/i2c.h>
>  #include <linux/interrupt.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/regmap.h>
> -#include <linux/slab.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/mfd/axp20x.h>
>  #include <linux/mfd/core.h>
> -#include <linux/of_device.h>
> -#include <linux/of_irq.h>
>  #include <linux/acpi.h>
>
>  #define AXP20X_OFF     0x80
> @@ -376,32 +374,6 @@ static const struct regmap_irq axp288_regmap_irqs[] = {
>         INIT_REGMAP_IRQ(AXP288, BC_USB_CHNG,            5, 1),
>  };
>
> -static const struct of_device_id axp20x_of_match[] = {
> -       { .compatible = "x-powers,axp152", .data = (void *) AXP152_ID },
> -       { .compatible = "x-powers,axp202", .data = (void *) AXP202_ID },
> -       { .compatible = "x-powers,axp209", .data = (void *) AXP209_ID },
> -       { .compatible = "x-powers,axp221", .data = (void *) AXP221_ID },
> -       { },
> -};
> -MODULE_DEVICE_TABLE(of, axp20x_of_match);
> -
> -/*
> - * This is useless for OF-enabled devices, but it is needed by I2C subsystem
> - */
> -static const struct i2c_device_id axp20x_i2c_id[] = {
> -       { },
> -};
> -MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);
> -
> -static const struct acpi_device_id axp20x_acpi_match[] = {
> -       {
> -               .id = "INT33F4",
> -               .driver_data = AXP288_ID,
> -       },
> -       { },
> -};
> -MODULE_DEVICE_TABLE(acpi, axp20x_acpi_match);
> -
>  static const struct regmap_irq_chip axp152_regmap_irq_chip = {
>         .name                   = "axp152_irq_chip",
>         .status_base            = AXP152_IRQ1_STATE,
> @@ -606,27 +578,8 @@ static void axp20x_power_off(void)
>                      AXP20X_OFF);
>  }
>
> -static int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev)
> +int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev)
>  {
> -       const struct acpi_device_id *acpi_id;
> -       const struct of_device_id *of_id;
> -
> -       if (dev->of_node) {
> -               of_id = of_match_device(axp20x_of_match, dev);
> -               if (!of_id) {
> -                       dev_err(dev, "Unable to match OF ID\n");
> -                       return -ENODEV;
> -               }
> -               axp20x->variant = (long) of_id->data;
> -       } else {
> -               acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
> -               if (!acpi_id || !acpi_id->driver_data) {
> -                       dev_err(dev, "Unable to match ACPI ID and data\n");
> -                       return -ENODEV;
> -               }
> -               axp20x->variant = (long) acpi_id->driver_data;
> -       }
> -
>         switch (axp20x->variant) {
>         case AXP152_ID:
>                 axp20x->nr_cells = ARRAY_SIZE(axp152_cells);
> @@ -662,38 +615,18 @@ static int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev)
>
>         return 0;
>  }
> +EXPORT_SYMBOL(axp20x_match_device);
>
> -static int axp20x_i2c_probe(struct i2c_client *i2c,
> -                        const struct i2c_device_id *id)
> +int axp20x_device_probe(struct axp20x_dev *axp20x)
>  {
> -       struct axp20x_dev *axp20x;
>         int ret;
>
> -       axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
> -       if (!axp20x)
> -               return -ENOMEM;
> -
> -       ret = axp20x_match_device(axp20x, &i2c->dev);
> -       if (ret)
> -               return ret;
> -
> -       axp20x->i2c_client = i2c;
> -       axp20x->dev = &i2c->dev;
> -       dev_set_drvdata(axp20x->dev, axp20x);
> -
> -       axp20x->regmap = devm_regmap_init_i2c(i2c, axp20x->regmap_cfg);
> -       if (IS_ERR(axp20x->regmap)) {
> -               ret = PTR_ERR(axp20x->regmap);
> -               dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
> -               return ret;
> -       }
> -
> -       ret = regmap_add_irq_chip(axp20x->regmap, i2c->irq,
> +       ret = regmap_add_irq_chip(axp20x->regmap, axp20x->irq,
>                                   IRQF_ONESHOT | IRQF_SHARED, -1,
>                                   axp20x->regmap_irq_chip,
>                                   &axp20x->regmap_irqc);
>         if (ret) {
> -               dev_err(&i2c->dev, "failed to add irq chip: %d\n", ret);
> +               dev_err(axp20x->dev, "failed to add irq chip: %d\n", ret);
>                 return ret;
>         }
>
> @@ -701,8 +634,8 @@ static int axp20x_i2c_probe(struct i2c_client *i2c,
>                         axp20x->nr_cells, NULL, 0, NULL);
>
>         if (ret) {
> -               dev_err(&i2c->dev, "failed to add MFD devices: %d\n", ret);
> -               regmap_del_irq_chip(i2c->irq, axp20x->regmap_irqc);
> +               dev_err(axp20x->dev, "failed to add MFD devices: %d\n", ret);
> +               regmap_del_irq_chip(axp20x->irq, axp20x->regmap_irqc);
>                 return ret;
>         }
>
> @@ -711,38 +644,25 @@ static int axp20x_i2c_probe(struct i2c_client *i2c,
>                 pm_power_off = axp20x_power_off;
>         }
>
> -       dev_info(&i2c->dev, "AXP20X driver loaded\n");
> +       dev_info(axp20x->dev, "AXP20X driver loaded\n");
>
>         return 0;
>  }
> +EXPORT_SYMBOL(axp20x_device_probe);
>
> -static int axp20x_i2c_remove(struct i2c_client *i2c)
> +int axp20x_device_remove(struct axp20x_dev *axp20x)
>  {
> -       struct axp20x_dev *axp20x = i2c_get_clientdata(i2c);
> -
>         if (axp20x == axp20x_pm_power_off) {
>                 axp20x_pm_power_off = NULL;
>                 pm_power_off = NULL;
>         }
>
>         mfd_remove_devices(axp20x->dev);
> -       regmap_del_irq_chip(axp20x->i2c_client->irq, axp20x->regmap_irqc);
> +       regmap_del_irq_chip(axp20x->irq, axp20x->regmap_irqc);
>
>         return 0;
>  }
> -
> -static struct i2c_driver axp20x_i2c_driver = {
> -       .driver = {
> -               .name   = "axp20x",
> -               .of_match_table = of_match_ptr(axp20x_of_match),
> -               .acpi_match_table = ACPI_PTR(axp20x_acpi_match),
> -       },
> -       .probe          = axp20x_i2c_probe,
> -       .remove         = axp20x_i2c_remove,
> -       .id_table       = axp20x_i2c_id,
> -};
> -
> -module_i2c_driver(axp20x_i2c_driver);
> +EXPORT_SYMBOL(axp20x_device_remove);
>
>  MODULE_DESCRIPTION("PMIC MFD core driver for AXP20X");
>  MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
> diff --git a/include/linux/mfd/axp20x.h b/include/linux/mfd/axp20x.h
> index b24c771cebd5..908f97f6e2d7 100644
> --- a/include/linux/mfd/axp20x.h
> +++ b/include/linux/mfd/axp20x.h
> @@ -396,7 +396,7 @@ enum axp288_irqs {
>
>  struct axp20x_dev {
>         struct device                   *dev;
> -       struct i2c_client               *i2c_client;
> +       int                             irq;
>         struct regmap                   *regmap;
>         struct regmap_irq_chip_data     *regmap_irqc;
>         long                            variant;
> @@ -462,4 +462,35 @@ static inline int axp20x_read_variable_width(struct regmap *regmap,
>         return result;
>  }
>
> +/**
> + * axp20x_match_device(): Setup axp20x variant related fields
> + *
> + * @axp20x: axp20x device to setup (.variant field must be set)
> + * @dev: device associated with this axp20x device
> + *
> + * This lets the axp20x core configure the mfd cells and register maps
> + * for later use.
> + */
> +int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev);
> +
> +/**
> + * axp20x_device_probe(): Probe a configured axp20x device
> + *
> + * @axp20x: axp20x device to probe (must be configured)
> + *
> + * This function lets the axp20x core register the axp20x mfd devices
> + * and irqchip. The axp20x device passed in must be fully configured
> + * with axp20x_match_device, its irq set, and regmap created.
> + */
> +int axp20x_device_probe(struct axp20x_dev *axp20x);
> +
> +/**
> + * axp20x_device_probe(): Remove a axp20x device
> + *
> + * @axp20x: axp20x device to remove
> + *
> + * This tells the axp20x core to remove the associated mfd devices
> + */
> +int axp20x_device_remove(struct axp20x_dev *axp20x);
> +
>  #endif /* __LINUX_MFD_AXP20X_H */
> --
> 2.6.2
>
> --
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Chen-Yu Tsai Nov. 24, 2015, 11:28 a.m. UTC | #2
Hi,

On Tue, Nov 24, 2015 at 5:37 PM, Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
> On Tue, Nov 24, 2015 at 5:48 AM, Chen-Yu Tsai <wens@csie.org> wrote:
>> The axp20x driver assumes the device is i2c based. This is not the
>> case with later chips, which use a proprietary 2 wire serial bus
>> by Allwinner called "Reduced Serial Bus".
>>
>> This patch follows the example of mfd/wm831x and splits it into
>> an interface independent core, and an i2c specific glue layer.
>> MFD_AXP20X and the new MFD_AXP20X_I2C are changed to tristate
>> symbols, allowing the driver to be built as modules.
>>
>> Included but unused header files are removed as well.
>>
>> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
>> ---
>>  drivers/mfd/Kconfig        |  14 +++--
>>  drivers/mfd/Makefile       |   1 +
>>  drivers/mfd/axp20x-i2c.c   | 127 +++++++++++++++++++++++++++++++++++++++++++++
>>  drivers/mfd/axp20x.c       | 108 +++++---------------------------------
>>  include/linux/mfd/axp20x.h |  33 +++++++++++-
>>  5 files changed, 183 insertions(+), 100 deletions(-)
>>  create mode 100644 drivers/mfd/axp20x-i2c.c
>>
>> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
>> index 4d92df6ef9fe..804cd3dcce32 100644
>> --- a/drivers/mfd/Kconfig
>> +++ b/drivers/mfd/Kconfig
>> @@ -91,14 +91,18 @@ config MFD_BCM590XX
>>           Support for the BCM590xx PMUs from Broadcom
>>
>>  config MFD_AXP20X
>> -       bool "X-Powers AXP20X"
>> +       tristate
>>         select MFD_CORE
>> -       select REGMAP_I2C
>>         select REGMAP_IRQ
>> -       depends on I2C=y
>> +
>> +config MFD_AXP20X_I2C
>> +       tristate "X-Powers AXP series PMICs with I2C"
>> +       select MFD_AXP20X
>> +       select REGMAP_I2C
>> +       depends on I2C
>>         help
>> -         If you say Y here you get support for the X-Powers AXP202, AXP209 and
>> -         AXP288 power management IC (PMIC).
>> +         If you say Y here you get support for the X-Powers AXP series power
>> +         management ICs (PMICs) controlled with I2C.
>>           This driver include only the core APIs. You have to select individual
>>           components like regulators or the PEK (Power Enable Key) under the
>>           corresponding menus.
>> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
>> index a8b76b81b467..a6913007d667 100644
>> --- a/drivers/mfd/Makefile
>> +++ b/drivers/mfd/Makefile
>> @@ -107,6 +107,7 @@ obj-$(CONFIG_PMIC_DA9052)   += da9052-core.o
>>  obj-$(CONFIG_MFD_DA9052_SPI)   += da9052-spi.o
>>  obj-$(CONFIG_MFD_DA9052_I2C)   += da9052-i2c.o
>>  obj-$(CONFIG_MFD_AXP20X)       += axp20x.o
>> +obj-$(CONFIG_MFD_AXP20X_I2C)   += axp20x-i2c.o
>>
>>  obj-$(CONFIG_MFD_LP3943)       += lp3943.o
>>  obj-$(CONFIG_MFD_LP8788)       += lp8788.o lp8788-irq.o
>> diff --git a/drivers/mfd/axp20x-i2c.c b/drivers/mfd/axp20x-i2c.c
>> new file mode 100644
>> index 000000000000..75b247af2514
>> --- /dev/null
>> +++ b/drivers/mfd/axp20x-i2c.c
>> @@ -0,0 +1,127 @@
>> +/*
>> + * axp20x-i2c.c - I2C driver for the X-Powers' Power Management ICs
>> + *
>> + * AXP20x typically comprises an adaptive USB-Compatible PWM charger, BUCK DC-DC
>> + * converters, LDOs, multiple 12-bit ADCs of voltage, current and temperature
>> + * as well as configurable GPIOs.
>> + *
>> + * This driver supports the I2C variants.
>> + *
>> + * Author: Carlo Caione <carlo@caione.org>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + */
>> +
>> +#include <linux/acpi.h>
>> +#include <linux/err.h>
>> +#include <linux/i2c.h>
>> +#include <linux/module.h>
>> +#include <linux/mfd/axp20x.h>
>> +#include <linux/of_device.h>
>> +#include <linux/regmap.h>
>> +#include <linux/slab.h>
>> +
>> +static const struct of_device_id axp20x_i2c_of_match[] = {
>> +       { .compatible = "x-powers,axp152", .data = (void *) AXP152_ID },
>> +       { .compatible = "x-powers,axp202", .data = (void *) AXP202_ID },
>> +       { .compatible = "x-powers,axp209", .data = (void *) AXP209_ID },
>> +       { .compatible = "x-powers,axp221", .data = (void *) AXP221_ID },
>> +       { },
>> +};
>> +MODULE_DEVICE_TABLE(of, axp20x_i2c_of_match);
>> +
>> +/*
>> + * This is useless for OF-enabled devices, but it is needed by I2C subsystem
>> + */
>> +static const struct i2c_device_id axp20x_i2c_id[] = {
>> +       { },
>> +};
>> +MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);
>> +
>> +static const struct acpi_device_id axp20x_i2c_acpi_match[] = {
>> +       {
>> +               .id = "INT33F4",
>> +               .driver_data = AXP288_ID,
>> +       },
>> +       { },
>> +};
>> +MODULE_DEVICE_TABLE(acpi, axp20x_i2c_acpi_match);
>> +
>> +static int axp20x_i2c_match_device(struct axp20x_dev *axp20x,
>> +                                  struct device *dev)
>> +{
>> +       const struct acpi_device_id *acpi_id;
>> +       const struct of_device_id *of_id;
>> +
>> +       if (dev->of_node) {
>
> What about
>
> if (…of_node) {
>       const struct of_device_id *id;
> …
> } else if ACPI_COMPANION(…) {
>       const struct acpi_device_id *id;
> …
> } else {
>  return -ENODEV;
> }

I really don't want to change code that I'm just moving around.
Same goes for the other comments about this patch. I can do another
patch on top of this to fix the style issues if it really bothers
people.


Regards
ChenYu

>> +               of_id = of_match_device(axp20x_i2c_of_match, dev);
>> +               if (!of_id) {
>> +                       dev_err(dev, "Unable to match OF ID\n");
>> +                       return -ENODEV;
>> +               }
>> +               axp20x->variant = (long) of_id->data;
>
> Extra space after casting.
>
>> +       } else {
>> +               acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
>> +               if (!acpi_id || !acpi_id->driver_data) {
>> +                       dev_err(dev, "Unable to match ACPI ID and data\n");
>> +                       return -ENODEV;
>> +               }
>> +               axp20x->variant = (long) acpi_id->driver_data;
>
> Ditto.
>
>> +       }
>> +
>> +       return axp20x_match_device(axp20x, dev);
>> +}
>> +
>> +static int axp20x_i2c_probe(struct i2c_client *i2c,
>> +                           const struct i2c_device_id *id)
>> +{
>> +       struct axp20x_dev *axp20x;
>> +       int ret;
>> +
>> +       axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
>> +       if (!axp20x)
>> +               return -ENOMEM;
>> +
>> +       ret = axp20x_i2c_match_device(axp20x, &i2c->dev);
>> +       if (ret)
>> +               return ret;
>> +
>> +       axp20x->dev = &i2c->dev;
>> +       axp20x->irq = i2c->irq;
>
> If you move _match_device() here you will be able to drop away struct
> device * parameter.
>
>> +       dev_set_drvdata(axp20x->dev, axp20x);
>> +
>> +       axp20x->regmap = devm_regmap_init_i2c(i2c, axp20x->regmap_cfg);
>> +       if (IS_ERR(axp20x->regmap)) {
>> +               ret = PTR_ERR(axp20x->regmap);
>> +               dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
>> +               return ret;
>> +       }
>> +
>> +       return axp20x_device_probe(axp20x);
>> +}
>> +
>> +static int axp20x_i2c_remove(struct i2c_client *i2c)
>> +{
>> +       struct axp20x_dev *axp20x = i2c_get_clientdata(i2c);
>> +
>> +       return axp20x_device_remove(axp20x);
>> +}
>> +
>> +static struct i2c_driver axp20x_i2c_driver = {
>> +       .driver = {
>> +               .name   = "axp20x",
>> +               .of_match_table = of_match_ptr(axp20x_i2c_of_match),
>> +               .acpi_match_table = ACPI_PTR(axp20x_i2c_acpi_match),
>> +       },
>> +       .probe          = axp20x_i2c_probe,
>> +       .remove         = axp20x_i2c_remove,
>> +       .id_table       = axp20x_i2c_id,
>> +};
>> +
>> +module_i2c_driver(axp20x_i2c_driver);
>> +
>> +MODULE_DESCRIPTION("PMIC MFD I2C driver for AXP20X");
>> +MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
>> +MODULE_LICENSE("GPL");
>> diff --git a/drivers/mfd/axp20x.c b/drivers/mfd/axp20x.c
>> index 9842199e2e6c..01f139856bf1 100644
>> --- a/drivers/mfd/axp20x.c
>> +++ b/drivers/mfd/axp20x.c
>> @@ -5,6 +5,8 @@
>>   * converters, LDOs, multiple 12-bit ADCs of voltage, current and temperature
>>   * as well as configurable GPIOs.
>>   *
>> + * This file contains the interface independent core functions.
>> + *
>>   * Author: Carlo Caione <carlo@caione.org>
>>   *
>>   * This program is free software; you can redistribute it and/or modify
>> @@ -13,18 +15,14 @@
>>   */
>>
>>  #include <linux/err.h>
>> -#include <linux/i2c.h>
>>  #include <linux/interrupt.h>
>>  #include <linux/kernel.h>
>>  #include <linux/module.h>
>>  #include <linux/pm_runtime.h>
>>  #include <linux/regmap.h>
>> -#include <linux/slab.h>
>>  #include <linux/regulator/consumer.h>
>>  #include <linux/mfd/axp20x.h>
>>  #include <linux/mfd/core.h>
>> -#include <linux/of_device.h>
>> -#include <linux/of_irq.h>
>>  #include <linux/acpi.h>
>>
>>  #define AXP20X_OFF     0x80
>> @@ -376,32 +374,6 @@ static const struct regmap_irq axp288_regmap_irqs[] = {
>>         INIT_REGMAP_IRQ(AXP288, BC_USB_CHNG,            5, 1),
>>  };
>>
>> -static const struct of_device_id axp20x_of_match[] = {
>> -       { .compatible = "x-powers,axp152", .data = (void *) AXP152_ID },
>> -       { .compatible = "x-powers,axp202", .data = (void *) AXP202_ID },
>> -       { .compatible = "x-powers,axp209", .data = (void *) AXP209_ID },
>> -       { .compatible = "x-powers,axp221", .data = (void *) AXP221_ID },
>> -       { },
>> -};
>> -MODULE_DEVICE_TABLE(of, axp20x_of_match);
>> -
>> -/*
>> - * This is useless for OF-enabled devices, but it is needed by I2C subsystem
>> - */
>> -static const struct i2c_device_id axp20x_i2c_id[] = {
>> -       { },
>> -};
>> -MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);
>> -
>> -static const struct acpi_device_id axp20x_acpi_match[] = {
>> -       {
>> -               .id = "INT33F4",
>> -               .driver_data = AXP288_ID,
>> -       },
>> -       { },
>> -};
>> -MODULE_DEVICE_TABLE(acpi, axp20x_acpi_match);
>> -
>>  static const struct regmap_irq_chip axp152_regmap_irq_chip = {
>>         .name                   = "axp152_irq_chip",
>>         .status_base            = AXP152_IRQ1_STATE,
>> @@ -606,27 +578,8 @@ static void axp20x_power_off(void)
>>                      AXP20X_OFF);
>>  }
>>
>> -static int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev)
>> +int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev)
>>  {
>> -       const struct acpi_device_id *acpi_id;
>> -       const struct of_device_id *of_id;
>> -
>> -       if (dev->of_node) {
>> -               of_id = of_match_device(axp20x_of_match, dev);
>> -               if (!of_id) {
>> -                       dev_err(dev, "Unable to match OF ID\n");
>> -                       return -ENODEV;
>> -               }
>> -               axp20x->variant = (long) of_id->data;
>> -       } else {
>> -               acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
>> -               if (!acpi_id || !acpi_id->driver_data) {
>> -                       dev_err(dev, "Unable to match ACPI ID and data\n");
>> -                       return -ENODEV;
>> -               }
>> -               axp20x->variant = (long) acpi_id->driver_data;
>> -       }
>> -
>>         switch (axp20x->variant) {
>>         case AXP152_ID:
>>                 axp20x->nr_cells = ARRAY_SIZE(axp152_cells);
>> @@ -662,38 +615,18 @@ static int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev)
>>
>>         return 0;
>>  }
>> +EXPORT_SYMBOL(axp20x_match_device);
>>
>> -static int axp20x_i2c_probe(struct i2c_client *i2c,
>> -                        const struct i2c_device_id *id)
>> +int axp20x_device_probe(struct axp20x_dev *axp20x)
>>  {
>> -       struct axp20x_dev *axp20x;
>>         int ret;
>>
>> -       axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
>> -       if (!axp20x)
>> -               return -ENOMEM;
>> -
>> -       ret = axp20x_match_device(axp20x, &i2c->dev);
>> -       if (ret)
>> -               return ret;
>> -
>> -       axp20x->i2c_client = i2c;
>> -       axp20x->dev = &i2c->dev;
>> -       dev_set_drvdata(axp20x->dev, axp20x);
>> -
>> -       axp20x->regmap = devm_regmap_init_i2c(i2c, axp20x->regmap_cfg);
>> -       if (IS_ERR(axp20x->regmap)) {
>> -               ret = PTR_ERR(axp20x->regmap);
>> -               dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
>> -               return ret;
>> -       }
>> -
>> -       ret = regmap_add_irq_chip(axp20x->regmap, i2c->irq,
>> +       ret = regmap_add_irq_chip(axp20x->regmap, axp20x->irq,
>>                                   IRQF_ONESHOT | IRQF_SHARED, -1,
>>                                   axp20x->regmap_irq_chip,
>>                                   &axp20x->regmap_irqc);
>>         if (ret) {
>> -               dev_err(&i2c->dev, "failed to add irq chip: %d\n", ret);
>> +               dev_err(axp20x->dev, "failed to add irq chip: %d\n", ret);
>>                 return ret;
>>         }
>>
>> @@ -701,8 +634,8 @@ static int axp20x_i2c_probe(struct i2c_client *i2c,
>>                         axp20x->nr_cells, NULL, 0, NULL);
>>
>>         if (ret) {
>> -               dev_err(&i2c->dev, "failed to add MFD devices: %d\n", ret);
>> -               regmap_del_irq_chip(i2c->irq, axp20x->regmap_irqc);
>> +               dev_err(axp20x->dev, "failed to add MFD devices: %d\n", ret);
>> +               regmap_del_irq_chip(axp20x->irq, axp20x->regmap_irqc);
>>                 return ret;
>>         }
>>
>> @@ -711,38 +644,25 @@ static int axp20x_i2c_probe(struct i2c_client *i2c,
>>                 pm_power_off = axp20x_power_off;
>>         }
>>
>> -       dev_info(&i2c->dev, "AXP20X driver loaded\n");
>> +       dev_info(axp20x->dev, "AXP20X driver loaded\n");
>>
>>         return 0;
>>  }
>> +EXPORT_SYMBOL(axp20x_device_probe);
>>
>> -static int axp20x_i2c_remove(struct i2c_client *i2c)
>> +int axp20x_device_remove(struct axp20x_dev *axp20x)
>>  {
>> -       struct axp20x_dev *axp20x = i2c_get_clientdata(i2c);
>> -
>>         if (axp20x == axp20x_pm_power_off) {
>>                 axp20x_pm_power_off = NULL;
>>                 pm_power_off = NULL;
>>         }
>>
>>         mfd_remove_devices(axp20x->dev);
>> -       regmap_del_irq_chip(axp20x->i2c_client->irq, axp20x->regmap_irqc);
>> +       regmap_del_irq_chip(axp20x->irq, axp20x->regmap_irqc);
>>
>>         return 0;
>>  }
>> -
>> -static struct i2c_driver axp20x_i2c_driver = {
>> -       .driver = {
>> -               .name   = "axp20x",
>> -               .of_match_table = of_match_ptr(axp20x_of_match),
>> -               .acpi_match_table = ACPI_PTR(axp20x_acpi_match),
>> -       },
>> -       .probe          = axp20x_i2c_probe,
>> -       .remove         = axp20x_i2c_remove,
>> -       .id_table       = axp20x_i2c_id,
>> -};
>> -
>> -module_i2c_driver(axp20x_i2c_driver);
>> +EXPORT_SYMBOL(axp20x_device_remove);
>>
>>  MODULE_DESCRIPTION("PMIC MFD core driver for AXP20X");
>>  MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
>> diff --git a/include/linux/mfd/axp20x.h b/include/linux/mfd/axp20x.h
>> index b24c771cebd5..908f97f6e2d7 100644
>> --- a/include/linux/mfd/axp20x.h
>> +++ b/include/linux/mfd/axp20x.h
>> @@ -396,7 +396,7 @@ enum axp288_irqs {
>>
>>  struct axp20x_dev {
>>         struct device                   *dev;
>> -       struct i2c_client               *i2c_client;
>> +       int                             irq;
>>         struct regmap                   *regmap;
>>         struct regmap_irq_chip_data     *regmap_irqc;
>>         long                            variant;
>> @@ -462,4 +462,35 @@ static inline int axp20x_read_variable_width(struct regmap *regmap,
>>         return result;
>>  }
>>
>> +/**
>> + * axp20x_match_device(): Setup axp20x variant related fields
>> + *
>> + * @axp20x: axp20x device to setup (.variant field must be set)
>> + * @dev: device associated with this axp20x device
>> + *
>> + * This lets the axp20x core configure the mfd cells and register maps
>> + * for later use.
>> + */
>> +int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev);
>> +
>> +/**
>> + * axp20x_device_probe(): Probe a configured axp20x device
>> + *
>> + * @axp20x: axp20x device to probe (must be configured)
>> + *
>> + * This function lets the axp20x core register the axp20x mfd devices
>> + * and irqchip. The axp20x device passed in must be fully configured
>> + * with axp20x_match_device, its irq set, and regmap created.
>> + */
>> +int axp20x_device_probe(struct axp20x_dev *axp20x);
>> +
>> +/**
>> + * axp20x_device_probe(): Remove a axp20x device
>> + *
>> + * @axp20x: axp20x device to remove
>> + *
>> + * This tells the axp20x core to remove the associated mfd devices
>> + */
>> +int axp20x_device_remove(struct axp20x_dev *axp20x);
>> +
>>  #endif /* __LINUX_MFD_AXP20X_H */
>> --
>> 2.6.2
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>
>
>
> --
> With Best Regards,
> Andy Shevchenko
Andy Shevchenko Nov. 24, 2015, 12:35 p.m. UTC | #3
On Tue, Nov 24, 2015 at 1:28 PM, Chen-Yu Tsai <wens@csie.org> wrote:
> Hi,
>
> On Tue, Nov 24, 2015 at 5:37 PM, Andy Shevchenko
> <andy.shevchenko@gmail.com> wrote:
>> On Tue, Nov 24, 2015 at 5:48 AM, Chen-Yu Tsai <wens@csie.org> wrote:
>>> The axp20x driver assumes the device is i2c based. This is not the
>>> case with later chips, which use a proprietary 2 wire serial bus
>>> by Allwinner called "Reduced Serial Bus".
>>>
>>> This patch follows the example of mfd/wm831x and splits it into
>>> an interface independent core, and an i2c specific glue layer.
>>> MFD_AXP20X and the new MFD_AXP20X_I2C are changed to tristate
>>> symbols, allowing the driver to be built as modules.
>>>
>>> Included but unused header files are removed as well.

So…

>>> +       if (dev->of_node) {
>>
>> What about
>>
>> if (…of_node) {
>>       const struct of_device_id *id;
>> …
>> } else if ACPI_COMPANION(…) {

This should be has_acpi_companion().

>>       const struct acpi_device_id *id;
>> …
>> } else {
>>  return -ENODEV;
>> }
>
> I really don't want to change code that I'm just moving around.
> Same goes for the other comments about this patch. I can do another
> patch on top of this to fix the style issues if it really bothers
> people.

Fair enough.
My comments mostly about unnecessity of second parameter in the functions.

So,  you already did some clean up in this patch (above), what about
to do another? I also prefer separate patch *before* you do a split.

>>> +       axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
>>> +       if (!axp20x)
>>> +               return -ENOMEM;
>>> +
>>> +       ret = axp20x_i2c_match_device(axp20x, &i2c->dev);
>>> +       if (ret)
>>> +               return ret;
>>> +
>>> +       axp20x->dev = &i2c->dev;
>>> +       axp20x->irq = i2c->irq;
>>
>> If you move _match_device() here you will be able to drop away struct
>> device * parameter.
Chen-Yu Tsai Nov. 24, 2015, 3:09 p.m. UTC | #4
On Tue, Nov 24, 2015 at 8:35 PM, Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
> On Tue, Nov 24, 2015 at 1:28 PM, Chen-Yu Tsai <wens@csie.org> wrote:
>> Hi,
>>
>> On Tue, Nov 24, 2015 at 5:37 PM, Andy Shevchenko
>> <andy.shevchenko@gmail.com> wrote:
>>> On Tue, Nov 24, 2015 at 5:48 AM, Chen-Yu Tsai <wens@csie.org> wrote:
>>>> The axp20x driver assumes the device is i2c based. This is not the
>>>> case with later chips, which use a proprietary 2 wire serial bus
>>>> by Allwinner called "Reduced Serial Bus".
>>>>
>>>> This patch follows the example of mfd/wm831x and splits it into
>>>> an interface independent core, and an i2c specific glue layer.
>>>> MFD_AXP20X and the new MFD_AXP20X_I2C are changed to tristate
>>>> symbols, allowing the driver to be built as modules.
>>>>
>>>> Included but unused header files are removed as well.
>
> So…
>
>>>> +       if (dev->of_node) {
>>>
>>> What about
>>>
>>> if (…of_node) {
>>>       const struct of_device_id *id;
>>> …
>>> } else if ACPI_COMPANION(…) {
>
> This should be has_acpi_companion().

I don't think the "else if" is necessary. There's only 2 possible ways
the device gets probed, either device tree or ACPI.

>>>       const struct acpi_device_id *id;
>>> …
>>> } else {
>>>  return -ENODEV;
>>> }
>>
>> I really don't want to change code that I'm just moving around.
>> Same goes for the other comments about this patch. I can do another
>> patch on top of this to fix the style issues if it really bothers
>> people.
>
> Fair enough.
> My comments mostly about unnecessity of second parameter in the functions.
>
> So,  you already did some clean up in this patch (above), what about
> to do another? I also prefer separate patch *before* you do a split.

Sure. I'll do a patch or 2 before the split. Would you mind if I add your
Suggested-by tag?


Regards
ChenYu

>>>> +       axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
>>>> +       if (!axp20x)
>>>> +               return -ENOMEM;
>>>> +
>>>> +       ret = axp20x_i2c_match_device(axp20x, &i2c->dev);
>>>> +       if (ret)
>>>> +               return ret;
>>>> +
>>>> +       axp20x->dev = &i2c->dev;
>>>> +       axp20x->irq = i2c->irq;
>>>
>>> If you move _match_device() here you will be able to drop away struct
>>> device * parameter.
>
> --
> With Best Regards,
> Andy Shevchenko
Andy Shevchenko Nov. 24, 2015, 3:21 p.m. UTC | #5
On Tue, Nov 24, 2015 at 5:09 PM, Chen-Yu Tsai <wens@csie.org> wrote:
> On Tue, Nov 24, 2015 at 8:35 PM, Andy Shevchenko
> <andy.shevchenko@gmail.com> wrote:
>> On Tue, Nov 24, 2015 at 1:28 PM, Chen-Yu Tsai <wens@csie.org> wrote:
>>> On Tue, Nov 24, 2015 at 5:37 PM, Andy Shevchenko
>>> <andy.shevchenko@gmail.com> wrote:
>>>> On Tue, Nov 24, 2015 at 5:48 AM, Chen-Yu Tsai <wens@csie.org> wrote:
>>>>> The axp20x driver assumes the device is i2c based. This is not the
>>>>> case with later chips, which use a proprietary 2 wire serial bus
>>>>> by Allwinner called "Reduced Serial Bus".
>>>>>
>>>>> This patch follows the example of mfd/wm831x and splits it into
>>>>> an interface independent core, and an i2c specific glue layer.
>>>>> MFD_AXP20X and the new MFD_AXP20X_I2C are changed to tristate
>>>>> symbols, allowing the driver to be built as modules.
>>>>>
>>>>> Included but unused header files are removed as well.
>>
>> So…
>>
>>>>> +       if (dev->of_node) {
>>>>
>>>> What about
>>>>
>>>> if (…of_node) {
>>>>       const struct of_device_id *id;
>>>> …
>>>> } else if ACPI_COMPANION(…) {
>>
>> This should be has_acpi_companion().
>
> I don't think the "else if" is necessary. There's only 2 possible ways
> the device gets probed, either device tree or ACPI.

OK.

It would be ideal to move to unified device properties API at some
point, but it's out of scope of this series anyway.

>
>>>>       const struct acpi_device_id *id;
>>>> …
>>>> } else {
>>>>  return -ENODEV;
>>>> }
>>>
>>> I really don't want to change code that I'm just moving around.
>>> Same goes for the other comments about this patch. I can do another
>>> patch on top of this to fix the style issues if it really bothers
>>> people.
>>
>> Fair enough.
>> My comments mostly about unnecessity of second parameter in the functions.
>>
>> So,  you already did some clean up in this patch (above), what about
>> to do another? I also prefer separate patch *before* you do a split.
>
> Sure. I'll do a patch or 2 before the split. Would you mind if I add your
> Suggested-by tag?

I would not.
diff mbox

Patch

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 4d92df6ef9fe..804cd3dcce32 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -91,14 +91,18 @@  config MFD_BCM590XX
 	  Support for the BCM590xx PMUs from Broadcom
 
 config MFD_AXP20X
-	bool "X-Powers AXP20X"
+	tristate
 	select MFD_CORE
-	select REGMAP_I2C
 	select REGMAP_IRQ
-	depends on I2C=y
+
+config MFD_AXP20X_I2C
+	tristate "X-Powers AXP series PMICs with I2C"
+	select MFD_AXP20X
+	select REGMAP_I2C
+	depends on I2C
 	help
-	  If you say Y here you get support for the X-Powers AXP202, AXP209 and
-	  AXP288 power management IC (PMIC).
+	  If you say Y here you get support for the X-Powers AXP series power
+	  management ICs (PMICs) controlled with I2C.
 	  This driver include only the core APIs. You have to select individual
 	  components like regulators or the PEK (Power Enable Key) under the
 	  corresponding menus.
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index a8b76b81b467..a6913007d667 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -107,6 +107,7 @@  obj-$(CONFIG_PMIC_DA9052)	+= da9052-core.o
 obj-$(CONFIG_MFD_DA9052_SPI)	+= da9052-spi.o
 obj-$(CONFIG_MFD_DA9052_I2C)	+= da9052-i2c.o
 obj-$(CONFIG_MFD_AXP20X)	+= axp20x.o
+obj-$(CONFIG_MFD_AXP20X_I2C)	+= axp20x-i2c.o
 
 obj-$(CONFIG_MFD_LP3943)	+= lp3943.o
 obj-$(CONFIG_MFD_LP8788)	+= lp8788.o lp8788-irq.o
diff --git a/drivers/mfd/axp20x-i2c.c b/drivers/mfd/axp20x-i2c.c
new file mode 100644
index 000000000000..75b247af2514
--- /dev/null
+++ b/drivers/mfd/axp20x-i2c.c
@@ -0,0 +1,127 @@ 
+/*
+ * axp20x-i2c.c - I2C driver for the X-Powers' Power Management ICs
+ *
+ * AXP20x typically comprises an adaptive USB-Compatible PWM charger, BUCK DC-DC
+ * converters, LDOs, multiple 12-bit ADCs of voltage, current and temperature
+ * as well as configurable GPIOs.
+ *
+ * This driver supports the I2C variants.
+ *
+ * Author: Carlo Caione <carlo@caione.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/acpi.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/mfd/axp20x.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+static const struct of_device_id axp20x_i2c_of_match[] = {
+	{ .compatible = "x-powers,axp152", .data = (void *) AXP152_ID },
+	{ .compatible = "x-powers,axp202", .data = (void *) AXP202_ID },
+	{ .compatible = "x-powers,axp209", .data = (void *) AXP209_ID },
+	{ .compatible = "x-powers,axp221", .data = (void *) AXP221_ID },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, axp20x_i2c_of_match);
+
+/*
+ * This is useless for OF-enabled devices, but it is needed by I2C subsystem
+ */
+static const struct i2c_device_id axp20x_i2c_id[] = {
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);
+
+static const struct acpi_device_id axp20x_i2c_acpi_match[] = {
+	{
+		.id = "INT33F4",
+		.driver_data = AXP288_ID,
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, axp20x_i2c_acpi_match);
+
+static int axp20x_i2c_match_device(struct axp20x_dev *axp20x,
+				   struct device *dev)
+{
+	const struct acpi_device_id *acpi_id;
+	const struct of_device_id *of_id;
+
+	if (dev->of_node) {
+		of_id = of_match_device(axp20x_i2c_of_match, dev);
+		if (!of_id) {
+			dev_err(dev, "Unable to match OF ID\n");
+			return -ENODEV;
+		}
+		axp20x->variant = (long) of_id->data;
+	} else {
+		acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
+		if (!acpi_id || !acpi_id->driver_data) {
+			dev_err(dev, "Unable to match ACPI ID and data\n");
+			return -ENODEV;
+		}
+		axp20x->variant = (long) acpi_id->driver_data;
+	}
+
+	return axp20x_match_device(axp20x, dev);
+}
+
+static int axp20x_i2c_probe(struct i2c_client *i2c,
+			    const struct i2c_device_id *id)
+{
+	struct axp20x_dev *axp20x;
+	int ret;
+
+	axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
+	if (!axp20x)
+		return -ENOMEM;
+
+	ret = axp20x_i2c_match_device(axp20x, &i2c->dev);
+	if (ret)
+		return ret;
+
+	axp20x->dev = &i2c->dev;
+	axp20x->irq = i2c->irq;
+	dev_set_drvdata(axp20x->dev, axp20x);
+
+	axp20x->regmap = devm_regmap_init_i2c(i2c, axp20x->regmap_cfg);
+	if (IS_ERR(axp20x->regmap)) {
+		ret = PTR_ERR(axp20x->regmap);
+		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
+		return ret;
+	}
+
+	return axp20x_device_probe(axp20x);
+}
+
+static int axp20x_i2c_remove(struct i2c_client *i2c)
+{
+	struct axp20x_dev *axp20x = i2c_get_clientdata(i2c);
+
+	return axp20x_device_remove(axp20x);
+}
+
+static struct i2c_driver axp20x_i2c_driver = {
+	.driver = {
+		.name	= "axp20x",
+		.of_match_table	= of_match_ptr(axp20x_i2c_of_match),
+		.acpi_match_table = ACPI_PTR(axp20x_i2c_acpi_match),
+	},
+	.probe		= axp20x_i2c_probe,
+	.remove		= axp20x_i2c_remove,
+	.id_table	= axp20x_i2c_id,
+};
+
+module_i2c_driver(axp20x_i2c_driver);
+
+MODULE_DESCRIPTION("PMIC MFD I2C driver for AXP20X");
+MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/mfd/axp20x.c b/drivers/mfd/axp20x.c
index 9842199e2e6c..01f139856bf1 100644
--- a/drivers/mfd/axp20x.c
+++ b/drivers/mfd/axp20x.c
@@ -5,6 +5,8 @@ 
  * converters, LDOs, multiple 12-bit ADCs of voltage, current and temperature
  * as well as configurable GPIOs.
  *
+ * This file contains the interface independent core functions.
+ *
  * Author: Carlo Caione <carlo@caione.org>
  *
  * This program is free software; you can redistribute it and/or modify
@@ -13,18 +15,14 @@ 
  */
 
 #include <linux/err.h>
-#include <linux/i2c.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
-#include <linux/slab.h>
 #include <linux/regulator/consumer.h>
 #include <linux/mfd/axp20x.h>
 #include <linux/mfd/core.h>
-#include <linux/of_device.h>
-#include <linux/of_irq.h>
 #include <linux/acpi.h>
 
 #define AXP20X_OFF	0x80
@@ -376,32 +374,6 @@  static const struct regmap_irq axp288_regmap_irqs[] = {
 	INIT_REGMAP_IRQ(AXP288, BC_USB_CHNG,            5, 1),
 };
 
-static const struct of_device_id axp20x_of_match[] = {
-	{ .compatible = "x-powers,axp152", .data = (void *) AXP152_ID },
-	{ .compatible = "x-powers,axp202", .data = (void *) AXP202_ID },
-	{ .compatible = "x-powers,axp209", .data = (void *) AXP209_ID },
-	{ .compatible = "x-powers,axp221", .data = (void *) AXP221_ID },
-	{ },
-};
-MODULE_DEVICE_TABLE(of, axp20x_of_match);
-
-/*
- * This is useless for OF-enabled devices, but it is needed by I2C subsystem
- */
-static const struct i2c_device_id axp20x_i2c_id[] = {
-	{ },
-};
-MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);
-
-static const struct acpi_device_id axp20x_acpi_match[] = {
-	{
-		.id = "INT33F4",
-		.driver_data = AXP288_ID,
-	},
-	{ },
-};
-MODULE_DEVICE_TABLE(acpi, axp20x_acpi_match);
-
 static const struct regmap_irq_chip axp152_regmap_irq_chip = {
 	.name			= "axp152_irq_chip",
 	.status_base		= AXP152_IRQ1_STATE,
@@ -606,27 +578,8 @@  static void axp20x_power_off(void)
 		     AXP20X_OFF);
 }
 
-static int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev)
+int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev)
 {
-	const struct acpi_device_id *acpi_id;
-	const struct of_device_id *of_id;
-
-	if (dev->of_node) {
-		of_id = of_match_device(axp20x_of_match, dev);
-		if (!of_id) {
-			dev_err(dev, "Unable to match OF ID\n");
-			return -ENODEV;
-		}
-		axp20x->variant = (long) of_id->data;
-	} else {
-		acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
-		if (!acpi_id || !acpi_id->driver_data) {
-			dev_err(dev, "Unable to match ACPI ID and data\n");
-			return -ENODEV;
-		}
-		axp20x->variant = (long) acpi_id->driver_data;
-	}
-
 	switch (axp20x->variant) {
 	case AXP152_ID:
 		axp20x->nr_cells = ARRAY_SIZE(axp152_cells);
@@ -662,38 +615,18 @@  static int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev)
 
 	return 0;
 }
+EXPORT_SYMBOL(axp20x_match_device);
 
-static int axp20x_i2c_probe(struct i2c_client *i2c,
-			 const struct i2c_device_id *id)
+int axp20x_device_probe(struct axp20x_dev *axp20x)
 {
-	struct axp20x_dev *axp20x;
 	int ret;
 
-	axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
-	if (!axp20x)
-		return -ENOMEM;
-
-	ret = axp20x_match_device(axp20x, &i2c->dev);
-	if (ret)
-		return ret;
-
-	axp20x->i2c_client = i2c;
-	axp20x->dev = &i2c->dev;
-	dev_set_drvdata(axp20x->dev, axp20x);
-
-	axp20x->regmap = devm_regmap_init_i2c(i2c, axp20x->regmap_cfg);
-	if (IS_ERR(axp20x->regmap)) {
-		ret = PTR_ERR(axp20x->regmap);
-		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
-		return ret;
-	}
-
-	ret = regmap_add_irq_chip(axp20x->regmap, i2c->irq,
+	ret = regmap_add_irq_chip(axp20x->regmap, axp20x->irq,
 				  IRQF_ONESHOT | IRQF_SHARED, -1,
 				  axp20x->regmap_irq_chip,
 				  &axp20x->regmap_irqc);
 	if (ret) {
-		dev_err(&i2c->dev, "failed to add irq chip: %d\n", ret);
+		dev_err(axp20x->dev, "failed to add irq chip: %d\n", ret);
 		return ret;
 	}
 
@@ -701,8 +634,8 @@  static int axp20x_i2c_probe(struct i2c_client *i2c,
 			axp20x->nr_cells, NULL, 0, NULL);
 
 	if (ret) {
-		dev_err(&i2c->dev, "failed to add MFD devices: %d\n", ret);
-		regmap_del_irq_chip(i2c->irq, axp20x->regmap_irqc);
+		dev_err(axp20x->dev, "failed to add MFD devices: %d\n", ret);
+		regmap_del_irq_chip(axp20x->irq, axp20x->regmap_irqc);
 		return ret;
 	}
 
@@ -711,38 +644,25 @@  static int axp20x_i2c_probe(struct i2c_client *i2c,
 		pm_power_off = axp20x_power_off;
 	}
 
-	dev_info(&i2c->dev, "AXP20X driver loaded\n");
+	dev_info(axp20x->dev, "AXP20X driver loaded\n");
 
 	return 0;
 }
+EXPORT_SYMBOL(axp20x_device_probe);
 
-static int axp20x_i2c_remove(struct i2c_client *i2c)
+int axp20x_device_remove(struct axp20x_dev *axp20x)
 {
-	struct axp20x_dev *axp20x = i2c_get_clientdata(i2c);
-
 	if (axp20x == axp20x_pm_power_off) {
 		axp20x_pm_power_off = NULL;
 		pm_power_off = NULL;
 	}
 
 	mfd_remove_devices(axp20x->dev);
-	regmap_del_irq_chip(axp20x->i2c_client->irq, axp20x->regmap_irqc);
+	regmap_del_irq_chip(axp20x->irq, axp20x->regmap_irqc);
 
 	return 0;
 }
-
-static struct i2c_driver axp20x_i2c_driver = {
-	.driver = {
-		.name	= "axp20x",
-		.of_match_table	= of_match_ptr(axp20x_of_match),
-		.acpi_match_table = ACPI_PTR(axp20x_acpi_match),
-	},
-	.probe		= axp20x_i2c_probe,
-	.remove		= axp20x_i2c_remove,
-	.id_table	= axp20x_i2c_id,
-};
-
-module_i2c_driver(axp20x_i2c_driver);
+EXPORT_SYMBOL(axp20x_device_remove);
 
 MODULE_DESCRIPTION("PMIC MFD core driver for AXP20X");
 MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
diff --git a/include/linux/mfd/axp20x.h b/include/linux/mfd/axp20x.h
index b24c771cebd5..908f97f6e2d7 100644
--- a/include/linux/mfd/axp20x.h
+++ b/include/linux/mfd/axp20x.h
@@ -396,7 +396,7 @@  enum axp288_irqs {
 
 struct axp20x_dev {
 	struct device			*dev;
-	struct i2c_client		*i2c_client;
+	int				irq;
 	struct regmap			*regmap;
 	struct regmap_irq_chip_data	*regmap_irqc;
 	long				variant;
@@ -462,4 +462,35 @@  static inline int axp20x_read_variable_width(struct regmap *regmap,
 	return result;
 }
 
+/**
+ * axp20x_match_device(): Setup axp20x variant related fields
+ *
+ * @axp20x: axp20x device to setup (.variant field must be set)
+ * @dev: device associated with this axp20x device
+ *
+ * This lets the axp20x core configure the mfd cells and register maps
+ * for later use.
+ */
+int axp20x_match_device(struct axp20x_dev *axp20x, struct device *dev);
+
+/**
+ * axp20x_device_probe(): Probe a configured axp20x device
+ *
+ * @axp20x: axp20x device to probe (must be configured)
+ *
+ * This function lets the axp20x core register the axp20x mfd devices
+ * and irqchip. The axp20x device passed in must be fully configured
+ * with axp20x_match_device, its irq set, and regmap created.
+ */
+int axp20x_device_probe(struct axp20x_dev *axp20x);
+
+/**
+ * axp20x_device_probe(): Remove a axp20x device
+ *
+ * @axp20x: axp20x device to remove
+ *
+ * This tells the axp20x core to remove the associated mfd devices
+ */
+int axp20x_device_remove(struct axp20x_dev *axp20x);
+
 #endif /* __LINUX_MFD_AXP20X_H */