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

Chen-Yu Tsai wens at csie.org
Tue Nov 24 03:28:25 PST 2015


Hi,

On Tue, Nov 24, 2015 at 5:37 PM, Andy Shevchenko
<andy.shevchenko at gmail.com> wrote:
> On Tue, Nov 24, 2015 at 5:48 AM, Chen-Yu Tsai <wens at 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 at 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 at 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 at 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 at 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 at 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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>
>
>
> --
> With Best Regards,
> Andy Shevchenko



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