diff mbox

[v2,1/8] mfd: AXP20x: Add mfd driver for AXP20x PMIC

Message ID 1394898225-28452-2-git-send-email-carlo@caione.org (mailing list archive)
State New, archived
Headers show

Commit Message

Carlo Caione March 15, 2014, 3:43 p.m. UTC
This patch introduces the preliminary support for PMICs X-Powers AXP202
and AXP209. The AXP209 and AXP202 are the PMUs (Power Management Unit)
used by A10, A13 and A20 SoCs and developed by X-Powers, a sister company
of Allwinner.

The core enables support for two subsystems:
- PEK (Power Enable Key)
- Regulators

Signed-off-by: Carlo Caione <carlo@caione.org>
---
 drivers/mfd/Kconfig        |  12 +++
 drivers/mfd/Makefile       |   1 +
 drivers/mfd/axp20x.c       | 247 +++++++++++++++++++++++++++++++++++++++++++++
 include/linux/mfd/axp20x.h | 179 ++++++++++++++++++++++++++++++++
 4 files changed, 439 insertions(+)
 create mode 100644 drivers/mfd/axp20x.c
 create mode 100644 include/linux/mfd/axp20x.h

Comments

Lee Jones March 18, 2014, 3:59 p.m. UTC | #1
> This patch introduces the preliminary support for PMICs X-Powers AXP202
> and AXP209. The AXP209 and AXP202 are the PMUs (Power Management Unit)
> used by A10, A13 and A20 SoCs and developed by X-Powers, a sister company
> of Allwinner.
> 
> The core enables support for two subsystems:
> - PEK (Power Enable Key)
> - Regulators
> 
> Signed-off-by: Carlo Caione <carlo@caione.org>
> ---
>  drivers/mfd/Kconfig        |  12 +++
>  drivers/mfd/Makefile       |   1 +
>  drivers/mfd/axp20x.c       | 247 +++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/mfd/axp20x.h | 179 ++++++++++++++++++++++++++++++++
>  4 files changed, 439 insertions(+)
>  create mode 100644 drivers/mfd/axp20x.c
>  create mode 100644 include/linux/mfd/axp20x.h

[...]

> +/*
> + * axp20x.c - mfd core driver for the X-Powers AXP202 and AXP209

MFD

[...]

> +static struct resource axp20x_pek_resources[] = {
> +	{
> +		.name	= "PEK_DBR",
> +		.start	= AXP20X_IRQ_PEK_RIS_EDGE,
> +		.end	= AXP20X_IRQ_PEK_RIS_EDGE,
> +		.flags	= IORESOURCE_IRQ,
> +	},
> +	{
> +		.name	= "PEK_DBF",
> +		.start	= AXP20X_IRQ_PEK_FAL_EDGE,
> +		.end	= AXP20X_IRQ_PEK_FAL_EDGE,
> +		.flags	= IORESOURCE_IRQ,
> +	},
> +};

[...] 

> +static struct mfd_cell axp20x_cells[] = {
> +	{
> +		.name		= "axp20x-pek",
> +		.num_resources	= ARRAY_SIZE(axp20x_pek_resources),
> +		.resources	= axp20x_pek_resources,
> +	}, {
> +		.name		= "axp20x-regulator",
> +	},
> +};

nit: The format of these two structs are inconsistent.

[...]

> +static int axp20x_i2c_probe(struct i2c_client *i2c,
> +			 const struct i2c_device_id *id)
> +{
> +	struct axp20x_dev *axp20x;
> +	const struct of_device_id *of_id;
> +	int ret;
> +
> +	axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
> +	if (!axp20x)
> +		return -ENOMEM;
> +
> +	of_id = of_match_device(axp20x_of_match, &i2c->dev);
> +	if (!of_id) {
> +		dev_err(&i2c->dev, "Unable to setup AXP20X data\n");
> +		return -ENODEV;
> +	}
> +	axp20x->variant = (int) of_id->data;

No need to cast from void *.

> +	axp20x->i2c_client = i2c;
> +	axp20x->dev = &i2c->dev;
> +	dev_set_drvdata(axp20x->dev, axp20x);
> +
> +	axp20x->regmap = devm_regmap_init_i2c(i2c, &axp20x_regmap_config);
> +	if (IS_ERR(axp20x->regmap)) {
> +		ret = PTR_ERR(axp20x->regmap);
> +		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
> +		return ret;
> +	}
> +
> +	axp20x->irq = i2c->irq;

Do you _really_ need this if you have 'axp20x->i2c_client->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);
> +		return ret;
> +	}
> +
> +	ret = mfd_add_devices(axp20x->dev, -1, axp20x_cells,
> +			      ARRAY_SIZE(axp20x_cells), NULL, 0, NULL);
> +
> +	if (ret) {
> +		dev_err(&i2c->dev, "failed to add MFD devices: %d\n", ret);
> +		goto mfd_err;
> +	}
> +
> +	if (!pm_power_off) {
> +		axp20x_pm_power_off = axp20x;
> +		pm_power_off = axp20x_power_off;
> +	}
> +
> +	dev_info(&i2c->dev, "AXP20X driver loaded\n");
> +
> +	return 0;
> +
> +mfd_err:
> +	regmap_del_irq_chip(axp20x->irq, axp20x->regmap_irqc);
> +
> +	return ret;

I'd say the goto is pointless if you're only using it once.

Instead move regmap_del_irq_chip() into mfd_add_devices()'s error
handler and return straight from there.

[...]

> +static const struct i2c_device_id axp20x_i2c_id[] = {
> +	{ "axp202", AXP202_ID },
> +	{ "axp209", AXP209_ID },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);

Isn't this redundant now that you're using of_id?

[...]

> +#ifndef __LINUX_MFD_AXP20X_H
> +#define __LINUX_MFD_AXP20X_H
> +
> +#define AXP202_ID			0
> +#define AXP209_ID			1

enum?

[...] 

> +struct axp20x_dev {
> +	struct device			*dev;
> +	struct i2c_client		*i2c_client;
> +	struct regmap			*regmap;
> +	struct regmap_irq_chip_data	*regmap_irqc;
> +	int				variant;
> +	int				irq;

i2c_client->irq?

> +};
> +
> +#endif /* __LINUX_MFD_AXP20X_H */
Carlo Caione March 22, 2014, 4:51 p.m. UTC | #2
On Tue, Mar 18, 2014 at 03:59:19PM +0000, Lee Jones wrote:
> > +static struct mfd_cell axp20x_cells[] = {
> > +	{
> > +		.name		= "axp20x-pek",
> > +		.num_resources	= ARRAY_SIZE(axp20x_pek_resources),
> > +		.resources	= axp20x_pek_resources,
> > +	}, {
> > +		.name		= "axp20x-regulator",
> > +	},
> > +};
> 
> nit: The format of these two structs are inconsistent.

Uhm, what do you mean?

> > +static int axp20x_i2c_probe(struct i2c_client *i2c,
> > +			 const struct i2c_device_id *id)
> > +{
> > +	struct axp20x_dev *axp20x;
> > +	const struct of_device_id *of_id;
> > +	int ret;
> > +
> > +	axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
> > +	if (!axp20x)
> > +		return -ENOMEM;
> > +
> > +	of_id = of_match_device(axp20x_of_match, &i2c->dev);
> > +	if (!of_id) {
> > +		dev_err(&i2c->dev, "Unable to setup AXP20X data\n");
> > +		return -ENODEV;
> > +	}
> > +	axp20x->variant = (int) of_id->data;
> 
> No need to cast from void *.

My compiler says otherwise :)

> [...]
> 
> > +static const struct i2c_device_id axp20x_i2c_id[] = {
> > +	{ "axp202", AXP202_ID },
> > +	{ "axp209", AXP209_ID },
> > +	{ }
> > +};
> > +MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);
> 
> Isn't this redundant now that you're using of_id?

It is not. Even it is unused it has to be in the driver otherwise the
driver is not loaded. Probably it is something wrong in the I2C core.

Best,
Mark Brown March 22, 2014, 5:33 p.m. UTC | #3
On Sat, Mar 22, 2014 at 05:51:32PM +0100, Carlo Caione wrote:
> On Tue, Mar 18, 2014 at 03:59:19PM +0000, Lee Jones wrote:

> > > +	of_id = of_match_device(axp20x_of_match, &i2c->dev);
> > > +	if (!of_id) {
> > > +		dev_err(&i2c->dev, "Unable to setup AXP20X data\n");
> > > +		return -ENODEV;
> > > +	}
> > > +	axp20x->variant = (int) of_id->data;

> > No need to cast from void *.

> My compiler says otherwise :)

Are you sure your compiler isn't correctly telling you not to cast away
const?  If the compiler is complaining about a cast on void then it's
spotted a definite bug.
Carlo Caione March 22, 2014, 6:05 p.m. UTC | #4
On Sat, Mar 22, 2014 at 6:33 PM, Mark Brown <broonie@kernel.org> wrote:
> On Sat, Mar 22, 2014 at 05:51:32PM +0100, Carlo Caione wrote:
>> On Tue, Mar 18, 2014 at 03:59:19PM +0000, Lee Jones wrote:
>
>> > > + of_id = of_match_device(axp20x_of_match, &i2c->dev);
>> > > + if (!of_id) {
>> > > +         dev_err(&i2c->dev, "Unable to setup AXP20X data\n");
>> > > +         return -ENODEV;
>> > > + }
>> > > + axp20x->variant = (int) of_id->data;
>
>> > No need to cast from void *.
>
>> My compiler says otherwise :)
>
> Are you sure your compiler isn't correctly telling you not to cast away
> const?  If the compiler is complaining about a cast on void then it's
> spotted a definite bug.

drivers/mfd/axp20x.c:172:18: warning: assignment makes integer from
pointer without a cast [enabled by default]
Carlo Caione March 22, 2014, 6:13 p.m. UTC | #5
On Sat, Mar 22, 2014 at 6:33 PM, Mark Brown <broonie@kernel.org> wrote:
> On Sat, Mar 22, 2014 at 05:51:32PM +0100, Carlo Caione wrote:
>> On Tue, Mar 18, 2014 at 03:59:19PM +0000, Lee Jones wrote:
>
>> > > + of_id = of_match_device(axp20x_of_match, &i2c->dev);
>> > > + if (!of_id) {
>> > > +         dev_err(&i2c->dev, "Unable to setup AXP20X data\n");
>> > > +         return -ENODEV;
>> > > + }
>> > > + axp20x->variant = (int) of_id->data;
>
>> > No need to cast from void *.
>
>> My compiler says otherwise :)
>
> Are you sure your compiler isn't correctly telling you not to cast away
> const?  If the compiler is complaining about a cast on void then it's
> spotted a definite bug.

[resend since gmail decided to not put broonie in CC]

drivers/mfd/axp20x.c:172:18: warning: assignment makes integer
frompointer without a cast [enabled by default]
Dmitry Torokhov March 22, 2014, 6:42 p.m. UTC | #6
On Sat, Mar 22, 2014 at 07:13:36PM +0100, Carlo Caione wrote:
> On Sat, Mar 22, 2014 at 6:33 PM, Mark Brown <broonie@kernel.org> wrote:
> > On Sat, Mar 22, 2014 at 05:51:32PM +0100, Carlo Caione wrote:
> >> On Tue, Mar 18, 2014 at 03:59:19PM +0000, Lee Jones wrote:
> >
> >> > > + of_id = of_match_device(axp20x_of_match, &i2c->dev);
> >> > > + if (!of_id) {
> >> > > +         dev_err(&i2c->dev, "Unable to setup AXP20X data\n");
> >> > > +         return -ENODEV;
> >> > > + }
> >> > > + axp20x->variant = (int) of_id->data;
> >
> >> > No need to cast from void *.
> >
> >> My compiler says otherwise :)
> >
> > Are you sure your compiler isn't correctly telling you not to cast away
> > const?  If the compiler is complaining about a cast on void then it's
> > spotted a definite bug.
> 
> [resend since gmail decided to not put broonie in CC]
> 
> drivers/mfd/axp20x.c:172:18: warning: assignment makes integer
> frompointer without a cast [enabled by default]

You need to cast to long, otherwise you will get warnings when compiling
on 64 bit arches.

Thanks.
Carlo Caione March 22, 2014, 7:08 p.m. UTC | #7
On Sat, Mar 22, 2014 at 11:42:01AM -0700, Dmitry Torokhov wrote:
> On Sat, Mar 22, 2014 at 07:13:36PM +0100, Carlo Caione wrote:
> > On Sat, Mar 22, 2014 at 6:33 PM, Mark Brown <broonie@kernel.org> wrote:
> > > On Sat, Mar 22, 2014 at 05:51:32PM +0100, Carlo Caione wrote:
> > >> On Tue, Mar 18, 2014 at 03:59:19PM +0000, Lee Jones wrote:
> > >
> > >> > > + of_id = of_match_device(axp20x_of_match, &i2c->dev);
> > >> > > + if (!of_id) {
> > >> > > +         dev_err(&i2c->dev, "Unable to setup AXP20X data\n");
> > >> > > +         return -ENODEV;
> > >> > > + }
> > >> > > + axp20x->variant = (int) of_id->data;
> > >
> > >> > No need to cast from void *.
> > >
> > >> My compiler says otherwise :)
> > >
> > > Are you sure your compiler isn't correctly telling you not to cast away
> > > const?  If the compiler is complaining about a cast on void then it's
> > > spotted a definite bug.
> > 
> > [resend since gmail decided to not put broonie in CC]
> > 
> > drivers/mfd/axp20x.c:172:18: warning: assignment makes integer
> > frompointer without a cast [enabled by default]
> 
> You need to cast to long, otherwise you will get warnings when compiling
> on 64 bit arches.

Actually no warning also with (int) cast.
Mark Brown March 22, 2014, 7:29 p.m. UTC | #8
On Sat, Mar 22, 2014 at 08:08:03PM +0100, Carlo Caione wrote:
> On Sat, Mar 22, 2014 at 11:42:01AM -0700, Dmitry Torokhov wrote:

> > > drivers/mfd/axp20x.c:172:18: warning: assignment makes integer
> > > frompointer without a cast [enabled by default]

> > You need to cast to long, otherwise you will get warnings when compiling
> > on 64 bit arches.

> Actually no warning also with (int) cast.

That's because you squashed it to something smaller than a long using
the cast.  The other option is to make the variable you're assigning to
suitable to hold the value - intptr_t or a long.
Lee Jones March 24, 2014, 8:34 a.m. UTC | #9
> > > +static struct mfd_cell axp20x_cells[] = {
> > > +	{
> > > +		.name		= "axp20x-pek",
> > > +		.num_resources	= ARRAY_SIZE(axp20x_pek_resources),
> > > +		.resources	= axp20x_pek_resources,
> > > +	}, {
> > > +		.name		= "axp20x-regulator",
> > > +	},
> > > +};
> > 
> > nit: The format of these two structs are inconsistent.
> 
> Uhm, what do you mean?

Well you've removed the struct above this one in your reply. Take a
look at my reply to you and see the differences between this _two_
structs, this being only one of them.

[...]

> > > +static const struct i2c_device_id axp20x_i2c_id[] = {
> > > +	{ "axp202", AXP202_ID },
> > > +	{ "axp209", AXP209_ID },
> > > +	{ }
> > > +};
> > > +MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);
> > 
> > Isn't this redundant now that you're using of_id?
> 
> It is not. Even it is unused it has to be in the driver otherwise the
> driver is not loaded. Probably it is something wrong in the I2C core.

Sorry, I should have been more specific. The I2C core requires this
struct, but the IDs are unused and redundant. Best remove them in
order to mitigate any confusion.
diff mbox

Patch

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 49bb445..24ba61a 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -59,6 +59,18 @@  config MFD_AAT2870_CORE
 	  additional drivers must be enabled in order to use the
 	  functionality of the device.
 
+config MFD_AXP20X
+	bool "X-Powers AXP20X"
+	select MFD_CORE
+	select REGMAP_I2C
+	select REGMAP_IRQ
+	depends on I2C=y
+	help
+	  If you say Y here you get support for the AXP20X.
+	  This driver provides common support for accessing the device,
+	  additional drivers must be enabled in order to use the
+	  functionality of the device.
+
 config MFD_CROS_EC
 	tristate "ChromeOS Embedded Controller"
 	select MFD_CORE
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 5aea5ef..fb773b5 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -101,6 +101,7 @@  obj-$(CONFIG_PMIC_DA9052)	+= da9052-irq.o
 obj-$(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-$(CONFIG_MFD_LP3943)	+= lp3943.o
 obj-$(CONFIG_MFD_LP8788)	+= lp8788.o lp8788-irq.o
diff --git a/drivers/mfd/axp20x.c b/drivers/mfd/axp20x.c
new file mode 100644
index 0000000..a790f0f
--- /dev/null
+++ b/drivers/mfd/axp20x.c
@@ -0,0 +1,247 @@ 
+/*
+ * axp20x.c - mfd core driver for the X-Powers AXP202 and AXP209
+ *
+ * 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/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>
+
+#define AXP20X_OFF	0x80
+
+static const struct regmap_range axp20x_writeable_ranges[] = {
+	regmap_reg_range(AXP20X_DATACACHE(0), AXP20X_IRQ5_STATE),
+	regmap_reg_range(AXP20X_DCDC_MODE, AXP20X_FG_RES),
+};
+
+static const struct regmap_range axp20x_volatile_ranges[] = {
+	regmap_reg_range(AXP20X_IRQ1_EN, AXP20X_IRQ5_STATE),
+};
+
+static const struct regmap_access_table axp20x_writeable_table = {
+	.yes_ranges	= axp20x_writeable_ranges,
+	.n_yes_ranges	= ARRAY_SIZE(axp20x_writeable_ranges),
+};
+
+static const struct regmap_access_table axp20x_volatile_table = {
+	.yes_ranges	= axp20x_volatile_ranges,
+	.n_yes_ranges	= ARRAY_SIZE(axp20x_volatile_ranges),
+};
+
+static struct resource axp20x_pek_resources[] = {
+	{
+		.name	= "PEK_DBR",
+		.start	= AXP20X_IRQ_PEK_RIS_EDGE,
+		.end	= AXP20X_IRQ_PEK_RIS_EDGE,
+		.flags	= IORESOURCE_IRQ,
+	},
+	{
+		.name	= "PEK_DBF",
+		.start	= AXP20X_IRQ_PEK_FAL_EDGE,
+		.end	= AXP20X_IRQ_PEK_FAL_EDGE,
+		.flags	= IORESOURCE_IRQ,
+	},
+};
+
+static const struct regmap_config axp20x_regmap_config = {
+	.reg_bits	= 8,
+	.val_bits	= 8,
+	.wr_table	= &axp20x_writeable_table,
+	.volatile_table	= &axp20x_volatile_table,
+	.max_register	= AXP20X_FG_RES,
+	.cache_type	= REGCACHE_RBTREE,
+};
+
+#define AXP20X_IRQ(_irq, _off, _mask) \
+	[AXP20X_IRQ_##_irq] = { .reg_offset = (_off), .mask = BIT(_mask) }
+
+static const struct regmap_irq axp20x_regmap_irqs[] = {
+	AXP20X_IRQ(ACIN_OVER_V,		0, 7),
+	AXP20X_IRQ(ACIN_PLUGIN,		0, 6),
+	AXP20X_IRQ(ACIN_REMOVAL,	0, 5),
+	AXP20X_IRQ(VBUS_OVER_V,		0, 4),
+	AXP20X_IRQ(VBUS_PLUGIN,		0, 3),
+	AXP20X_IRQ(VBUS_REMOVAL,	0, 2),
+	AXP20X_IRQ(VBUS_V_LOW,		0, 1),
+	AXP20X_IRQ(BATT_PLUGIN,		1, 7),
+	AXP20X_IRQ(BATT_REMOVAL,	1, 6),
+	AXP20X_IRQ(BATT_ENT_ACT_MODE,	1, 5),
+	AXP20X_IRQ(BATT_EXIT_ACT_MODE,	1, 4),
+	AXP20X_IRQ(CHARG,		1, 3),
+	AXP20X_IRQ(CHARG_DONE,		1, 2),
+	AXP20X_IRQ(BATT_TEMP_HIGH,	1, 1),
+	AXP20X_IRQ(BATT_TEMP_LOW,	1, 0),
+	AXP20X_IRQ(DIE_TEMP_HIGH,	2, 7),
+	AXP20X_IRQ(CHARG_I_LOW,		2, 6),
+	AXP20X_IRQ(DCDC1_V_LONG,	2, 5),
+	AXP20X_IRQ(DCDC2_V_LONG,	2, 4),
+	AXP20X_IRQ(DCDC3_V_LONG,	2, 3),
+	AXP20X_IRQ(PEK_SHORT,		2, 1),
+	AXP20X_IRQ(PEK_LONG,		2, 0),
+	AXP20X_IRQ(N_OE_PWR_ON,		3, 7),
+	AXP20X_IRQ(N_OE_PWR_OFF,	3, 6),
+	AXP20X_IRQ(VBUS_VALID,		3, 5),
+	AXP20X_IRQ(VBUS_NOT_VALID,	3, 4),
+	AXP20X_IRQ(VBUS_SESS_VALID,	3, 3),
+	AXP20X_IRQ(VBUS_SESS_END,	3, 2),
+	AXP20X_IRQ(LOW_PWR_LVL1,	3, 1),
+	AXP20X_IRQ(LOW_PWR_LVL2,	3, 0),
+	AXP20X_IRQ(TIMER,		4, 7),
+	AXP20X_IRQ(PEK_RIS_EDGE,	4, 6),
+	AXP20X_IRQ(PEK_FAL_EDGE,	4, 5),
+	AXP20X_IRQ(GPIO3_INPUT,		4, 3),
+	AXP20X_IRQ(GPIO2_INPUT,		4, 2),
+	AXP20X_IRQ(GPIO1_INPUT,		4, 1),
+	AXP20X_IRQ(GPIO0_INPUT,		4, 0),
+};
+
+static const struct regmap_irq_chip axp20x_regmap_irq_chip = {
+	.name			= "axp20x_irq_chip",
+	.status_base		= AXP20X_IRQ1_STATE,
+	.ack_base		= AXP20X_IRQ1_STATE,
+	.mask_base		= AXP20X_IRQ1_EN,
+	.num_regs		= 5,
+	.irqs			= axp20x_regmap_irqs,
+	.num_irqs		= ARRAY_SIZE(axp20x_regmap_irqs),
+	.mask_invert		= true,
+	.init_ack_masked	= true,
+};
+
+static struct mfd_cell axp20x_cells[] = {
+	{
+		.name		= "axp20x-pek",
+		.num_resources	= ARRAY_SIZE(axp20x_pek_resources),
+		.resources	= axp20x_pek_resources,
+	}, {
+		.name		= "axp20x-regulator",
+	},
+};
+
+const struct of_device_id axp20x_of_match[] = {
+	{ .compatible = "x-powers,axp202", .data = (void *) AXP202_ID },
+	{ .compatible = "x-powers,axp209", .data = (void *) AXP209_ID },
+	{ },
+};
+
+static struct axp20x_dev *axp20x_pm_power_off;
+static void axp20x_power_off(void)
+{
+	regmap_write(axp20x_pm_power_off->regmap, AXP20X_OFF_CTRL,
+		     AXP20X_OFF);
+}
+
+static int axp20x_i2c_probe(struct i2c_client *i2c,
+			 const struct i2c_device_id *id)
+{
+	struct axp20x_dev *axp20x;
+	const struct of_device_id *of_id;
+	int ret;
+
+	axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
+	if (!axp20x)
+		return -ENOMEM;
+
+	of_id = of_match_device(axp20x_of_match, &i2c->dev);
+	if (!of_id) {
+		dev_err(&i2c->dev, "Unable to setup AXP20X data\n");
+		return -ENODEV;
+	}
+	axp20x->variant = (int) of_id->data;
+
+	axp20x->i2c_client = i2c;
+	axp20x->dev = &i2c->dev;
+	dev_set_drvdata(axp20x->dev, axp20x);
+
+	axp20x->regmap = devm_regmap_init_i2c(i2c, &axp20x_regmap_config);
+	if (IS_ERR(axp20x->regmap)) {
+		ret = PTR_ERR(axp20x->regmap);
+		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
+		return ret;
+	}
+
+	axp20x->irq = 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);
+		return ret;
+	}
+
+	ret = mfd_add_devices(axp20x->dev, -1, axp20x_cells,
+			      ARRAY_SIZE(axp20x_cells), NULL, 0, NULL);
+
+	if (ret) {
+		dev_err(&i2c->dev, "failed to add MFD devices: %d\n", ret);
+		goto mfd_err;
+	}
+
+	if (!pm_power_off) {
+		axp20x_pm_power_off = axp20x;
+		pm_power_off = axp20x_power_off;
+	}
+
+	dev_info(&i2c->dev, "AXP20X driver loaded\n");
+
+	return 0;
+
+mfd_err:
+	regmap_del_irq_chip(axp20x->irq, axp20x->regmap_irqc);
+
+	return ret;
+}
+
+static int axp20x_i2c_remove(struct i2c_client *i2c)
+{
+	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);
+
+	return 0;
+}
+
+static const struct i2c_device_id axp20x_i2c_id[] = {
+	{ "axp202", AXP202_ID },
+	{ "axp209", AXP209_ID },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);
+
+static struct i2c_driver axp20x_i2c_driver = {
+	.driver = {
+		.name	= "axp20x",
+		.owner	= THIS_MODULE,
+		.of_match_table	= of_match_ptr(axp20x_of_match),
+	},
+	.probe		= axp20x_i2c_probe,
+	.remove		= axp20x_i2c_remove,
+	.id_table	= axp20x_i2c_id,
+};
+
+module_i2c_driver(axp20x_i2c_driver);
+
+MODULE_DESCRIPTION("PMIC MFD core driver for AXP20X");
+MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/axp20x.h b/include/linux/mfd/axp20x.h
new file mode 100644
index 0000000..86d446e
--- /dev/null
+++ b/include/linux/mfd/axp20x.h
@@ -0,0 +1,179 @@ 
+/*
+ * Functions to access AXP20X power management chip.
+ *
+ * Copyright (C) 2013, 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.
+ */
+
+#ifndef __LINUX_MFD_AXP20X_H
+#define __LINUX_MFD_AXP20X_H
+
+#define AXP202_ID			0
+#define AXP209_ID			1
+
+#define AXP20X_DATACACHE(m)		(0x04 + (m))
+
+/* Power supply */
+#define AXP20X_PWR_INPUT_STATUS		0x00
+#define AXP20X_PWR_OP_MODE		0x01
+#define AXP20X_USB_OTG_STATUS		0x02
+#define AXP20X_PWR_OUT_CTRL		0x12
+#define AXP20X_DCDC2_V_OUT		0x23
+#define AXP20X_DCDC2_LDO3_V_SCAL	0x25
+#define AXP20X_DCDC3_V_OUT		0x27
+#define AXP20X_LDO24_V_OUT		0x28
+#define AXP20X_LDO3_V_OUT		0x29
+#define AXP20X_VBUS_IPSOUT_MGMT		0x30
+#define AXP20X_V_OFF			0x31
+#define AXP20X_OFF_CTRL			0x32
+#define AXP20X_CHRG_CTRL1		0x33
+#define AXP20X_CHRG_CTRL2		0x34
+#define AXP20X_CHRG_BAK_CTRL		0x35
+#define AXP20X_PEK_KEY			0x36
+#define AXP20X_DCDC_FREQ		0x37
+#define AXP20X_V_LTF_CHRG		0x38
+#define AXP20X_V_HTF_CHRG		0x39
+#define AXP20X_APS_WARN_L1		0x3a
+#define AXP20X_APS_WARN_L2		0x3b
+#define AXP20X_V_LTF_DISCHRG		0x3c
+#define AXP20X_V_HTF_DISCHRG		0x3d
+
+/* Interrupt */
+#define AXP20X_IRQ1_EN			0x40
+#define AXP20X_IRQ2_EN			0x41
+#define AXP20X_IRQ3_EN			0x42
+#define AXP20X_IRQ4_EN			0x43
+#define AXP20X_IRQ5_EN			0x44
+#define AXP20X_IRQ1_STATE		0x48
+#define AXP20X_IRQ2_STATE		0x49
+#define AXP20X_IRQ3_STATE		0x4a
+#define AXP20X_IRQ4_STATE		0x4b
+#define AXP20X_IRQ5_STATE		0x4c
+
+/* ADC */
+#define AXP20X_ACIN_V_ADC_H		0x56
+#define AXP20X_ACIN_V_ADC_L		0x57
+#define AXP20X_ACIN_I_ADC_H		0x58
+#define AXP20X_ACIN_I_ADC_L		0x59
+#define AXP20X_VBUS_V_ADC_H		0x5a
+#define AXP20X_VBUS_V_ADC_L		0x5b
+#define AXP20X_VBUS_I_ADC_H		0x5c
+#define AXP20X_VBUS_I_ADC_L		0x5d
+#define AXP20X_TEMP_ADC_H		0x5e
+#define AXP20X_TEMP_ADC_L		0x5f
+#define AXP20X_TS_IN_H			0x62
+#define AXP20X_TS_IN_L			0x63
+#define AXP20X_GPIO0_V_ADC_H		0x64
+#define AXP20X_GPIO0_V_ADC_L		0x65
+#define AXP20X_GPIO1_V_ADC_H		0x66
+#define AXP20X_GPIO1_V_ADC_L		0x67
+#define AXP20X_PWR_BATT_H		0x70
+#define AXP20X_PWR_BATT_M		0x71
+#define AXP20X_PWR_BATT_L		0x72
+#define AXP20X_BATT_V_H			0x78
+#define AXP20X_BATT_V_L			0x79
+#define AXP20X_BATT_CHRG_I_H		0x7a
+#define AXP20X_BATT_CHRG_I_L		0x7b
+#define AXP20X_BATT_DISCHRG_I_H		0x7c
+#define AXP20X_BATT_DISCHRG_I_L		0x7d
+#define AXP20X_IPSOUT_V_HIGH_H		0x7e
+#define AXP20X_IPSOUT_V_HIGH_L		0x7f
+
+/* Power supply */
+#define AXP20X_DCDC_MODE		0x80
+#define AXP20X_ADC_EN1			0x82
+#define AXP20X_ADC_EN2			0x83
+#define AXP20X_ADC_RATE			0x84
+#define AXP20X_GPIO10_IN_RANGE		0x85
+#define AXP20X_GPIO1_ADC_IRQ_RIS	0x86
+#define AXP20X_GPIO1_ADC_IRQ_FAL	0x87
+#define AXP20X_TIMER_CTRL		0x8a
+#define AXP20X_VBUS_MON			0x8b
+#define AXP20X_OVER_TMP			0x8f
+
+/* GPIO */
+#define AXP20X_GPIO0_CTRL		0x90
+#define AXP20X_LDO5_V_OUT		0x91
+#define AXP20X_GPIO1_CTRL		0x92
+#define AXP20X_GPIO2_CTRL		0x93
+#define AXP20X_GPIO20_SS		0x94
+#define AXP20X_GPIO3_CTRL		0x95
+
+/* Battery */
+#define AXP20X_CHRG_CC_31_24		0xb0
+#define AXP20X_CHRG_CC_23_16		0xb1
+#define AXP20X_CHRG_CC_15_8		0xb2
+#define AXP20X_CHRG_CC_7_0		0xb3
+#define AXP20X_DISCHRG_CC_31_24		0xb4
+#define AXP20X_DISCHRG_CC_23_16		0xb5
+#define AXP20X_DISCHRG_CC_15_8		0xb6
+#define AXP20X_DISCHRG_CC_7_0		0xb7
+#define AXP20X_CC_CTRL			0xb8
+#define AXP20X_FG_RES			0xb9
+
+/* Regulators IDs */
+enum {
+	AXP20X_LDO1 = 0,
+	AXP20X_LDO2,
+	AXP20X_LDO3,
+	AXP20X_LDO4,
+	AXP20X_LDO5,
+	AXP20X_DCDC2,
+	AXP20X_DCDC3,
+	AXP20X_REG_ID_MAX,
+};
+
+/* IRQs */
+enum {
+	AXP20X_IRQ_ACIN_OVER_V = 1,
+	AXP20X_IRQ_ACIN_PLUGIN,
+	AXP20X_IRQ_ACIN_REMOVAL,
+	AXP20X_IRQ_VBUS_OVER_V,
+	AXP20X_IRQ_VBUS_PLUGIN,
+	AXP20X_IRQ_VBUS_REMOVAL,
+	AXP20X_IRQ_VBUS_V_LOW,
+	AXP20X_IRQ_BATT_PLUGIN,
+	AXP20X_IRQ_BATT_REMOVAL,
+	AXP20X_IRQ_BATT_ENT_ACT_MODE,
+	AXP20X_IRQ_BATT_EXIT_ACT_MODE,
+	AXP20X_IRQ_CHARG,
+	AXP20X_IRQ_CHARG_DONE,
+	AXP20X_IRQ_BATT_TEMP_HIGH,
+	AXP20X_IRQ_BATT_TEMP_LOW,
+	AXP20X_IRQ_DIE_TEMP_HIGH,
+	AXP20X_IRQ_CHARG_I_LOW,
+	AXP20X_IRQ_DCDC1_V_LONG,
+	AXP20X_IRQ_DCDC2_V_LONG,
+	AXP20X_IRQ_DCDC3_V_LONG,
+	AXP20X_IRQ_PEK_SHORT = 22,
+	AXP20X_IRQ_PEK_LONG,
+	AXP20X_IRQ_N_OE_PWR_ON,
+	AXP20X_IRQ_N_OE_PWR_OFF,
+	AXP20X_IRQ_VBUS_VALID,
+	AXP20X_IRQ_VBUS_NOT_VALID,
+	AXP20X_IRQ_VBUS_SESS_VALID,
+	AXP20X_IRQ_VBUS_SESS_END,
+	AXP20X_IRQ_LOW_PWR_LVL1,
+	AXP20X_IRQ_LOW_PWR_LVL2,
+	AXP20X_IRQ_TIMER,
+	AXP20X_IRQ_PEK_RIS_EDGE,
+	AXP20X_IRQ_PEK_FAL_EDGE,
+	AXP20X_IRQ_GPIO3_INPUT,
+	AXP20X_IRQ_GPIO2_INPUT,
+	AXP20X_IRQ_GPIO1_INPUT,
+	AXP20X_IRQ_GPIO0_INPUT,
+};
+
+struct axp20x_dev {
+	struct device			*dev;
+	struct i2c_client		*i2c_client;
+	struct regmap			*regmap;
+	struct regmap_irq_chip_data	*regmap_irqc;
+	int				variant;
+	int				irq;
+};
+
+#endif /* __LINUX_MFD_AXP20X_H */