[PATCHv3,1/4] mc13xxx-core: Consolidate common code to prepare for separate i2c and spi

Commit Message

Marc Reilly Dec. 20, 2010, 3:50 a.m. UTC

None

Comments

Uwe Kleine-König Dec. 20, 2010, 8:31 a.m. UTC | #1

On Mon, Dec 20, 2010 at 02:50:52PM +1100, Marc Reilly wrote:
> This patch moves common mc13xxx definitions to the header file in
> preparation for separate i2c and spi driver modules.
> spi specific functions are also removed.
> 
> Changes to the mc13xxx struct are:
> removing the redundant irq member,
> adding driver read/write function ptrs,
> adding ictype
This list isn't complete, but see below.

I don't like that after this patch the driver isn't functional, because
you removed the spi functionality which breaks bisection.

> Signed-off-by: Marc Reilly <[e-mail]>
> ---
>  drivers/mfd/mc13xxx-core.c  |  207 +++++++-----------------------------------
>  include/linux/mfd/mc13xxx.h |   77 +++++++++++-----
>  2 files changed, 87 insertions(+), 197 deletions(-)
> 
> diff --git a/drivers/mfd/mc13xxx-core.c b/drivers/mfd/mc13xxx-core.c
> index a2ac2ed..3367a40 100644
> --- a/drivers/mfd/mc13xxx-core.c
> +++ b/drivers/mfd/mc13xxx-core.c
> @@ -9,24 +9,14 @@
>   * the terms of the GNU General Public License version 2 as published by the
>   * Free Software Foundation.
>   */
> -
(hmm.  I think there is no style guide for that, but I know people who
think that this nl should be there.  So IMHO don't touch this.)

>  #include <linux/slab.h>
>  #include <linux/module.h>
>  #include <linux/platform_device.h>
>  #include <linux/mutex.h>
>  #include <linux/interrupt.h>
> -#include <linux/spi/spi.h>
>  #include <linux/mfd/core.h>
>  #include <linux/mfd/mc13xxx.h>
>  
> -struct mc13xxx {
> -	struct spi_device *spidev;
> -	struct mutex lock;
> -	int irq;
> -
> -	irq_handler_t irqhandler[MC13XXX_NUM_IRQ];
> -	void *irqdata[MC13XXX_NUM_IRQ];
> -};
>  
>  struct mc13783 {
>  	struct mc13xxx mc13xxx;
> @@ -150,99 +140,53 @@ EXPORT_SYMBOL(mc13783_to_mc13xxx);
>  void mc13xxx_lock(struct mc13xxx *mc13xxx)
>  {
>  	if (!mutex_trylock(&mc13xxx->lock)) {
> -		dev_dbg(&mc13xxx->spidev->dev, "wait for %s from %pf\n",
> +		dev_dbg(mc13xxx->dev, "wait for %s from %pf\n",
>  				__func__, __builtin_return_address(0));
>  
>  		mutex_lock(&mc13xxx->lock);
>  	}
> -	dev_dbg(&mc13xxx->spidev->dev, "%s from %pf\n",
> +	dev_dbg(mc13xxx->dev, "%s from %pf\n",
>  			__func__, __builtin_return_address(0));
>  }
>  EXPORT_SYMBOL(mc13xxx_lock);
>  
>  void mc13xxx_unlock(struct mc13xxx *mc13xxx)
>  {
> -	dev_dbg(&mc13xxx->spidev->dev, "%s from %pf\n",
> +	dev_dbg(mc13xxx->dev, "%s from %pf\n",
>  			__func__, __builtin_return_address(0));
>  	mutex_unlock(&mc13xxx->lock);
>  }
>  EXPORT_SYMBOL(mc13xxx_unlock);
>  
> -#define MC13XXX_REGOFFSET_SHIFT 25
>  int mc13xxx_reg_read(struct mc13xxx *mc13xxx, unsigned int offset, u32 *val)
>  {
> -	struct spi_transfer t;
> -	struct spi_message m;
>  	int ret;
> -
>  	BUG_ON(!mutex_is_locked(&mc13xxx->lock));
>  
>  	if (offset > MC13XXX_NUMREGS)
>  		return -EINVAL;
>  
> -	*val = offset << MC13XXX_REGOFFSET_SHIFT;
> -
> -	memset(&t, 0, sizeof(t));
> -
> -	t.tx_buf = val;
> -	t.rx_buf = val;
> -	t.len = sizeof(u32);
> -
> -	spi_message_init(&m);
> -	spi_message_add_tail(&t, &m);
> -
> -	ret = spi_sync(mc13xxx->spidev, &m);
> -
> -	/* error in message.status implies error return from spi_sync */
> -	BUG_ON(!ret && m.status);
> +	ret = mc13xxx->read_dev(mc13xxx, offset, val);
> +	dev_vdbg(mc13xxx->dev, "[0x%02x] -> 0x%06x\n", offset, *val);
>  
> -	if (ret)
> -		return ret;
> -
> -	*val &= 0xffffff;
> -
> -	dev_vdbg(&mc13xxx->spidev->dev, "[0x%02x] -> 0x%06x\n", offset, *val);
> -
> -	return 0;
> +	return ret;
>  }
>  EXPORT_SYMBOL(mc13xxx_reg_read);
>  
> +
no please

>  int mc13xxx_reg_write(struct mc13xxx *mc13xxx, unsigned int offset, u32 val)
>  {
> -	u32 buf;
> -	struct spi_transfer t;
> -	struct spi_message m;
> -	int ret;
> -
>  	BUG_ON(!mutex_is_locked(&mc13xxx->lock));
> -
> -	dev_vdbg(&mc13xxx->spidev->dev, "[0x%02x] <- 0x%06x\n", offset, val);
> +	dev_vdbg(mc13xxx->dev, "[0x%02x] <- 0x%06x\n", offset, val);
>  
>  	if (offset > MC13XXX_NUMREGS || val > 0xffffff)
>  		return -EINVAL;
>  
> -	buf = 1 << 31 | offset << MC13XXX_REGOFFSET_SHIFT | val;
> -
> -	memset(&t, 0, sizeof(t));
> -
> -	t.tx_buf = &buf;
> -	t.rx_buf = &buf;
> -	t.len = sizeof(u32);
> -
> -	spi_message_init(&m);
> -	spi_message_add_tail(&t, &m);
> -
> -	ret = spi_sync(mc13xxx->spidev, &m);
> -
> -	BUG_ON(!ret && m.status);
> -
> -	if (ret)
> -		return ret;
> -
> -	return 0;
> +	return mc13xxx->write_dev(mc13xxx, offset, val);
>  }
>  EXPORT_SYMBOL(mc13xxx_reg_write);
>  
> +
no please

>  int mc13xxx_reg_rmw(struct mc13xxx *mc13xxx, unsigned int offset,
>  		u32 mask, u32 val)
>  {
> @@ -445,7 +389,7 @@ static int mc13xxx_irq_handle(struct mc13xxx *mc13xxx,
>  			if (handled == IRQ_HANDLED)
>  				num_handled++;
>  		} else {
> -			dev_err(&mc13xxx->spidev->dev,
> +			dev_err(mc13xxx->dev,
>  					"BUG: irq %u but no handler\n",
>  					baseirq + irq);
>  
> @@ -481,11 +425,6 @@ static irqreturn_t mc13xxx_irq_thread(int irq, void *data)
>  	return IRQ_RETVAL(handled);
>  }
>  
> -enum mc13xxx_id {
> -	MC13XXX_ID_MC13783,
> -	MC13XXX_ID_MC13892,
> -	MC13XXX_ID_INVALID,
> -};
>  
>  const char *mc13xxx_chipname[] = {
>  	[MC13XXX_ID_MC13783] = "mc13783",
> @@ -493,13 +432,16 @@ const char *mc13xxx_chipname[] = {
>  };
>  
>  #define maskval(reg, mask)	(((reg) & (mask)) >> __ffs(mask))
> -static int mc13xxx_identify(struct mc13xxx *mc13xxx, enum mc13xxx_id *id)
> +static int mc13xxx_identify(struct mc13xxx *mc13xxx)
>  {
>  	u32 icid;
>  	u32 revision;
> -	const char *name;
>  	int ret;
>  
> +	/* Get the generation ID from register 46, as apparently some older
/* should be on a seperate line

> +	 * ic revisions only have this info at this location. Newer ICs seem to
> +	 * have both.
> +	 */
>  	ret = mc13xxx_reg_read(mc13xxx, 46, &icid);
>  	if (ret)
>  		return ret;
> @@ -508,26 +450,22 @@ static int mc13xxx_identify(struct mc13xxx *mc13xxx, enum mc13xxx_id *id)
>  
>  	switch (icid) {
>  	case 2:
> -		*id = MC13XXX_ID_MC13783;
> -		name = "mc13783";
> +		mc13xxx->ictype = MC13XXX_ID_MC13783;
>  		break;
>  	case 7:
> -		*id = MC13XXX_ID_MC13892;
> -		name = "mc13892";
> +		mc13xxx->ictype = MC13XXX_ID_MC13892;
>  		break;
>  	default:
> -		*id = MC13XXX_ID_INVALID;
> +		mc13xxx->ictype = MC13XXX_ID_INVALID;
>  		break;
>  	}
>  
> -	if (*id == MC13XXX_ID_MC13783 || *id == MC13XXX_ID_MC13892) {
> +	if (mc13xxx->ictype == MC13XXX_ID_MC13783 ||
> +			mc13xxx->ictype == MC13XXX_ID_MC13892) {
>  		ret = mc13xxx_reg_read(mc13xxx, MC13XXX_REVISION, &revision);
> -		if (ret)
> -			return ret;
> -
> -		dev_info(&mc13xxx->spidev->dev, "%s: rev: %d.%d, "
> +		dev_info(mc13xxx->dev, "%s: rev: %d.%d, "
>  				"fin: %d, fab: %d, icid: %d/%d\n",
> -				mc13xxx_chipname[*id],
> +				mc13xxx_chipname[mc13xxx->ictype],
>  				maskval(revision, MC13XXX_REVISION_REVFULL),
>  				maskval(revision, MC13XXX_REVISION_REVMETAL),
>  				maskval(revision, MC13XXX_REVISION_FIN),
> @@ -536,26 +474,12 @@ static int mc13xxx_identify(struct mc13xxx *mc13xxx, enum mc13xxx_id *id)
>  				maskval(revision, MC13XXX_REVISION_ICIDCODE));
>  	}
>  
> -	if (*id != MC13XXX_ID_INVALID) {
> -		const struct spi_device_id *devid =
> -			spi_get_device_id(mc13xxx->spidev);
> -		if (!devid || devid->driver_data != *id)
> -			dev_warn(&mc13xxx->spidev->dev, "device id doesn't "
> -					"match auto detection!\n");
> -	}
> -
> -	return 0;
> +	return (mc13xxx->ictype == MC13XXX_ID_INVALID) ? -ENODEV : 0;
>  }
>  
>  static const char *mc13xxx_get_chipname(struct mc13xxx *mc13xxx)
>  {
> -	const struct spi_device_id *devid =
> -		spi_get_device_id(mc13xxx->spidev);
> -
> -	if (!devid)
> -		return NULL;
> -
> -	return mc13xxx_chipname[devid->driver_data];
> +	return mc13xxx_chipname[mc13xxx->ictype];
>  }
>  
>  #include <linux/mfd/mc13783.h>
> @@ -563,7 +487,7 @@ static const char *mc13xxx_get_chipname(struct mc13xxx *mc13xxx)
>  int mc13xxx_get_flags(struct mc13xxx *mc13xxx)
>  {
>  	struct mc13xxx_platform_data *pdata =
> -		dev_get_platdata(&mc13xxx->spidev->dev);
> +		dev_get_platdata(mc13xxx->dev);
>  
>  	return pdata->flags;
>  }
> @@ -601,7 +525,7 @@ int mc13783_adc_do_conversion(struct mc13783 *mc13783, unsigned int mode,
>  	};
>  	init_completion(&adcdone_data.done);
>  
> -	dev_dbg(&mc13xxx->spidev->dev, "%s\n", __func__);
> +	dev_dbg(mc13xxx->dev, "%s\n", __func__);
>  
>  	mc13xxx_lock(mc13xxx);
>  
> @@ -643,7 +567,7 @@ int mc13783_adc_do_conversion(struct mc13783 *mc13783, unsigned int mode,
>  		return -EINVAL;
>  	}
>  
> -	dev_dbg(&mc13783->mc13xxx.spidev->dev, "%s: request irq\n", __func__);
> +	dev_dbg(mc13783->mc13xxx.dev, "%s: request irq\n", __func__);
>  	mc13xxx_irq_request(mc13xxx, MC13783_IRQ_ADCDONE,
>  			mc13783_handler_adcdone, __func__, &adcdone_data);
>  	mc13xxx_irq_ack(mc13xxx, MC13783_IRQ_ADCDONE);
> @@ -701,7 +625,7 @@ static int mc13xxx_add_subdevice_pdata(struct mc13xxx *mc13xxx,
>  	if (!cell.name)
>  		return -ENOMEM;
>  
> -	return mfd_add_devices(&mc13xxx->spidev->dev, -1, &cell, 1, NULL, 0);
> +	return mfd_add_devices(mc13xxx->dev, -1, &cell, 1, NULL, 0);
>  }
>  
>  static int mc13xxx_add_subdevice(struct mc13xxx *mc13xxx, const char *format)
> @@ -709,29 +633,16 @@ static int mc13xxx_add_subdevice(struct mc13xxx *mc13xxx, const char *format)
>  	return mc13xxx_add_subdevice_pdata(mc13xxx, format, NULL, 0);
>  }
>  
> -static int mc13xxx_probe(struct spi_device *spi)
> +int mc13xxx_common_init(struct mc13xxx *mc13xxx,
> +			struct mc13xxx_platform_data *pdata, int irq)
>  {
> -	struct mc13xxx *mc13xxx;
> -	struct mc13xxx_platform_data *pdata = dev_get_platdata(&spi->dev);
> -	enum mc13xxx_id id;
>  	int ret;
>  
> -	mc13xxx = kzalloc(sizeof(*mc13xxx), GFP_KERNEL);
> -	if (!mc13xxx)
> -		return -ENOMEM;
> -
> -	dev_set_drvdata(&spi->dev, mc13xxx);
> -	spi->mode = SPI_MODE_0 | SPI_CS_HIGH;
> -	spi->bits_per_word = 32;
> -	spi_setup(spi);
> -
> -	mc13xxx->spidev = spi;
> -
>  	mutex_init(&mc13xxx->lock);
>  	mc13xxx_lock(mc13xxx);
>  
> -	ret = mc13xxx_identify(mc13xxx, &id);
> -	if (ret || id == MC13XXX_ID_INVALID)
> +	ret = mc13xxx_identify(mc13xxx);
> +	if (ret)
>  		goto err_revision;
>  
>  	/* mask all irqs */
> @@ -743,14 +654,13 @@ static int mc13xxx_probe(struct spi_device *spi)
>  	if (ret)
>  		goto err_mask;
>  
> -	ret = request_threaded_irq(spi->irq, NULL, mc13xxx_irq_thread,
> +	ret = request_threaded_irq(irq, NULL, mc13xxx_irq_thread,
>  			IRQF_ONESHOT | IRQF_TRIGGER_HIGH, "mc13xxx", mc13xxx);
>  
>  	if (ret) {
>  err_mask:
>  err_revision:
>  		mutex_unlock(&mc13xxx->lock);
> -		dev_set_drvdata(&spi->dev, NULL);
>  		kfree(mc13xxx);
>  		return ret;
>  	}
> @@ -786,54 +696,7 @@ err_revision:
>  
>  	return 0;
>  }
> -
> -static int __devexit mc13xxx_remove(struct spi_device *spi)
> -{
> -	struct mc13xxx *mc13xxx = dev_get_drvdata(&spi->dev);
> -
> -	free_irq(mc13xxx->spidev->irq, mc13xxx);
> -
> -	mfd_remove_devices(&spi->dev);
> -
> -	kfree(mc13xxx);
> -
> -	return 0;
> -}
> -
> -static const struct spi_device_id mc13xxx_device_id[] = {
> -	{
> -		.name = "mc13783",
> -		.driver_data = MC13XXX_ID_MC13783,
> -	}, {
> -		.name = "mc13892",
> -		.driver_data = MC13XXX_ID_MC13892,
> -	}, {
> -		/* sentinel */
> -	}
> -};
> -
> -static struct spi_driver mc13xxx_driver = {
> -	.id_table = mc13xxx_device_id,
> -	.driver = {
> -		.name = "mc13xxx",
> -		.bus = &spi_bus_type,
> -		.owner = THIS_MODULE,
> -	},
> -	.probe = mc13xxx_probe,
> -	.remove = __devexit_p(mc13xxx_remove),
> -};
> -
> -static int __init mc13xxx_init(void)
> -{
> -	return spi_register_driver(&mc13xxx_driver);
> -}
> -subsys_initcall(mc13xxx_init);
> -
> -static void __exit mc13xxx_exit(void)
> -{
> -	spi_unregister_driver(&mc13xxx_driver);
> -}
> -module_exit(mc13xxx_exit);
> +EXPORT_SYMBOL_GPL(mc13xxx_common_init);
>  
>  MODULE_DESCRIPTION("Core driver for Freescale MC13XXX PMIC");
>  MODULE_AUTHOR("Uwe Kleine-Koenig <[e-mail]>");
> diff --git a/include/linux/mfd/mc13xxx.h b/include/linux/mfd/mc13xxx.h
> index a1d391b..d7c18d7 100644
> --- a/include/linux/mfd/mc13xxx.h
> +++ b/include/linux/mfd/mc13xxx.h
> @@ -11,7 +11,53 @@
>  
>  #include <linux/interrupt.h>
>  
> -struct mc13xxx;
> +#define MC13XXX_IRQ_ADCDONE	0
> +#define MC13XXX_IRQ_ADCBISDONE	1
> +#define MC13XXX_IRQ_TS		2
> +#define MC13XXX_IRQ_CHGDET	6
> +#define MC13XXX_IRQ_CHGREV	8
> +#define MC13XXX_IRQ_CHGSHORT	9
> +#define MC13XXX_IRQ_CCCV	10
> +#define MC13XXX_IRQ_CHGCURR	11
> +#define MC13XXX_IRQ_BPON	12
> +#define MC13XXX_IRQ_LOBATL	13
> +#define MC13XXX_IRQ_LOBATH	14
> +#define MC13XXX_IRQ_1HZ		24
> +#define MC13XXX_IRQ_TODA	25
> +#define MC13XXX_IRQ_SYSRST	30
> +#define MC13XXX_IRQ_RTCRST	31
> +#define MC13XXX_IRQ_PC		32
> +#define MC13XXX_IRQ_WARM	33
> +#define MC13XXX_IRQ_MEMHLD	34
> +#define MC13XXX_IRQ_THWARNL	36
> +#define MC13XXX_IRQ_THWARNH	37
> +#define MC13XXX_IRQ_CLK		38
> +
> +#define MC13XXX_NUM_IRQ		46
> +
> +
> +enum mc13xxx_id {
> +	MC13XXX_ID_MC13783,
> +	MC13XXX_ID_MC13892,
> +	MC13XXX_ID_INVALID,
> +};
> +
> +struct mc13xxx {
> +	union {
> +		struct spi_device *spidev;
> +		struct i2c_client *i2cclient;
> +	};
I'd do this in a later patch.  IMHO the first patch should only shuffle
code around without changing any behaviour.

> +	struct device *dev;
> +	enum mc13xxx_id ictype;
> +
> +	struct mutex lock;
> +
> +	int (*read_dev)(struct mc13xxx *, unsigned int, u32 *);
> +	int (*write_dev)(struct mc13xxx *, unsigned int, u32);
> +
> +	irq_handler_t irqhandler[MC13XXX_NUM_IRQ];
> +	void *irqdata[MC13XXX_NUM_IRQ];
> +};
>  
>  void mc13xxx_lock(struct mc13xxx *mc13xxx);
>  void mc13xxx_unlock(struct mc13xxx *mc13xxx);
> @@ -21,6 +67,11 @@ int mc13xxx_reg_write(struct mc13xxx *mc13xxx, unsigned int offset, u32 val);
>  int mc13xxx_reg_rmw(struct mc13xxx *mc13xxx, unsigned int offset,
>  		u32 mask, u32 val);
>  
> +struct mc13xxx_platform_data;
> +
> +int mc13xxx_common_init(struct mc13xxx *mc13xxx,
> +			struct mc13xxx_platform_data *pdata, int irq);
> +
>  int mc13xxx_get_flags(struct mc13xxx *mc13xxx);
>  
>  int mc13xxx_irq_request(struct mc13xxx *mc13xxx, int irq,
> @@ -37,30 +88,6 @@ int mc13xxx_irq_ack(struct mc13xxx *mc13xxx, int irq);
>  
>  int mc13xxx_get_flags(struct mc13xxx *mc13xxx);
>  
> -#define MC13XXX_IRQ_ADCDONE	0
> -#define MC13XXX_IRQ_ADCBISDONE	1
> -#define MC13XXX_IRQ_TS		2
> -#define MC13XXX_IRQ_CHGDET	6
> -#define MC13XXX_IRQ_CHGREV	8
> -#define MC13XXX_IRQ_CHGSHORT	9
> -#define MC13XXX_IRQ_CCCV	10
> -#define MC13XXX_IRQ_CHGCURR	11
> -#define MC13XXX_IRQ_BPON	12
> -#define MC13XXX_IRQ_LOBATL	13
> -#define MC13XXX_IRQ_LOBATH	14
> -#define MC13XXX_IRQ_1HZ		24
> -#define MC13XXX_IRQ_TODA	25
> -#define MC13XXX_IRQ_SYSRST	30
> -#define MC13XXX_IRQ_RTCRST	31
> -#define MC13XXX_IRQ_PC		32
> -#define MC13XXX_IRQ_WARM	33
> -#define MC13XXX_IRQ_MEMHLD	34
> -#define MC13XXX_IRQ_THWARNL	36
> -#define MC13XXX_IRQ_THWARNH	37
> -#define MC13XXX_IRQ_CLK		38
> -
> -#define MC13XXX_NUM_IRQ		46
> -
why don't you keep these at their original place?

Uwe

Patch

diff --git a/drivers/mfd/mc13xxx-core.c b/drivers/mfd/mc13xxx-core.c
index a2ac2ed..3367a40 100644
--- a/drivers/mfd/mc13xxx-core.c
+++ b/drivers/mfd/mc13xxx-core.c
@@ -9,24 +9,14 @@ 
  * the terms of the GNU General Public License version 2 as published by the
  * Free Software Foundation.
  */
-
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/mutex.h>
 #include <linux/interrupt.h>
-#include <linux/spi/spi.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/mc13xxx.h>
 
-struct mc13xxx {
-	struct spi_device *spidev;
-	struct mutex lock;
-	int irq;
-
-	irq_handler_t irqhandler[MC13XXX_NUM_IRQ];
-	void *irqdata[MC13XXX_NUM_IRQ];
-};
 
 struct mc13783 {
 	struct mc13xxx mc13xxx;
@@ -150,99 +140,53 @@  EXPORT_SYMBOL(mc13783_to_mc13xxx);
 void mc13xxx_lock(struct mc13xxx *mc13xxx)
 {
 	if (!mutex_trylock(&mc13xxx->lock)) {
-		dev_dbg(&mc13xxx->spidev->dev, "wait for %s from %pf\n",
+		dev_dbg(mc13xxx->dev, "wait for %s from %pf\n",
 				__func__, __builtin_return_address(0));
 
 		mutex_lock(&mc13xxx->lock);
 	}
-	dev_dbg(&mc13xxx->spidev->dev, "%s from %pf\n",
+	dev_dbg(mc13xxx->dev, "%s from %pf\n",
 			__func__, __builtin_return_address(0));
 }
 EXPORT_SYMBOL(mc13xxx_lock);
 
 void mc13xxx_unlock(struct mc13xxx *mc13xxx)
 {
-	dev_dbg(&mc13xxx->spidev->dev, "%s from %pf\n",
+	dev_dbg(mc13xxx->dev, "%s from %pf\n",
 			__func__, __builtin_return_address(0));
 	mutex_unlock(&mc13xxx->lock);
 }
 EXPORT_SYMBOL(mc13xxx_unlock);
 
-#define MC13XXX_REGOFFSET_SHIFT 25
 int mc13xxx_reg_read(struct mc13xxx *mc13xxx, unsigned int offset, u32 *val)
 {
-	struct spi_transfer t;
-	struct spi_message m;
 	int ret;
-
 	BUG_ON(!mutex_is_locked(&mc13xxx->lock));
 
 	if (offset > MC13XXX_NUMREGS)
 		return -EINVAL;
 
-	*val = offset << MC13XXX_REGOFFSET_SHIFT;
-
-	memset(&t, 0, sizeof(t));
-
-	t.tx_buf = val;
-	t.rx_buf = val;
-	t.len = sizeof(u32);
-
-	spi_message_init(&m);
-	spi_message_add_tail(&t, &m);
-
-	ret = spi_sync(mc13xxx->spidev, &m);
-
-	/* error in message.status implies error return from spi_sync */
-	BUG_ON(!ret && m.status);
+	ret = mc13xxx->read_dev(mc13xxx, offset, val);
+	dev_vdbg(mc13xxx->dev, "[0x%02x] -> 0x%06x\n", offset, *val);
 
-	if (ret)
-		return ret;
-
-	*val &= 0xffffff;
-
-	dev_vdbg(&mc13xxx->spidev->dev, "[0x%02x] -> 0x%06x\n", offset, *val);
-
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL(mc13xxx_reg_read);
 
+
 int mc13xxx_reg_write(struct mc13xxx *mc13xxx, unsigned int offset, u32 val)
 {
-	u32 buf;
-	struct spi_transfer t;
-	struct spi_message m;
-	int ret;
-
 	BUG_ON(!mutex_is_locked(&mc13xxx->lock));
-
-	dev_vdbg(&mc13xxx->spidev->dev, "[0x%02x] <- 0x%06x\n", offset, val);
+	dev_vdbg(mc13xxx->dev, "[0x%02x] <- 0x%06x\n", offset, val);
 
 	if (offset > MC13XXX_NUMREGS || val > 0xffffff)
 		return -EINVAL;
 
-	buf = 1 << 31 | offset << MC13XXX_REGOFFSET_SHIFT | val;
-
-	memset(&t, 0, sizeof(t));
-
-	t.tx_buf = &buf;
-	t.rx_buf = &buf;
-	t.len = sizeof(u32);
-
-	spi_message_init(&m);
-	spi_message_add_tail(&t, &m);
-
-	ret = spi_sync(mc13xxx->spidev, &m);
-
-	BUG_ON(!ret && m.status);
-
-	if (ret)
-		return ret;
-
-	return 0;
+	return mc13xxx->write_dev(mc13xxx, offset, val);
 }
 EXPORT_SYMBOL(mc13xxx_reg_write);
 
+
 int mc13xxx_reg_rmw(struct mc13xxx *mc13xxx, unsigned int offset,
 		u32 mask, u32 val)
 {
@@ -445,7 +389,7 @@  static int mc13xxx_irq_handle(struct mc13xxx *mc13xxx,
 			if (handled == IRQ_HANDLED)
 				num_handled++;
 		} else {
-			dev_err(&mc13xxx->spidev->dev,
+			dev_err(mc13xxx->dev,
 					"BUG: irq %u but no handler\n",
 					baseirq + irq);
 
@@ -481,11 +425,6 @@  static irqreturn_t mc13xxx_irq_thread(int irq, void *data)
 	return IRQ_RETVAL(handled);
 }
 
-enum mc13xxx_id {
-	MC13XXX_ID_MC13783,
-	MC13XXX_ID_MC13892,
-	MC13XXX_ID_INVALID,
-};
 
 const char *mc13xxx_chipname[] = {
 	[MC13XXX_ID_MC13783] = "mc13783",
@@ -493,13 +432,16 @@  const char *mc13xxx_chipname[] = {
 };
 
 #define maskval(reg, mask)	(((reg) & (mask)) >> __ffs(mask))
-static int mc13xxx_identify(struct mc13xxx *mc13xxx, enum mc13xxx_id *id)
+static int mc13xxx_identify(struct mc13xxx *mc13xxx)
 {
 	u32 icid;
 	u32 revision;
-	const char *name;
 	int ret;
 
+	/* Get the generation ID from register 46, as apparently some older
+	 * ic revisions only have this info at this location. Newer ICs seem to
+	 * have both.
+	 */
 	ret = mc13xxx_reg_read(mc13xxx, 46, &icid);
 	if (ret)
 		return ret;
@@ -508,26 +450,22 @@  static int mc13xxx_identify(struct mc13xxx *mc13xxx, enum mc13xxx_id *id)
 
 	switch (icid) {
 	case 2:
-		*id = MC13XXX_ID_MC13783;
-		name = "mc13783";
+		mc13xxx->ictype = MC13XXX_ID_MC13783;
 		break;
 	case 7:
-		*id = MC13XXX_ID_MC13892;
-		name = "mc13892";
+		mc13xxx->ictype = MC13XXX_ID_MC13892;
 		break;
 	default:
-		*id = MC13XXX_ID_INVALID;
+		mc13xxx->ictype = MC13XXX_ID_INVALID;
 		break;
 	}
 
-	if (*id == MC13XXX_ID_MC13783 || *id == MC13XXX_ID_MC13892) {
+	if (mc13xxx->ictype == MC13XXX_ID_MC13783 ||
+			mc13xxx->ictype == MC13XXX_ID_MC13892) {
 		ret = mc13xxx_reg_read(mc13xxx, MC13XXX_REVISION, &revision);
-		if (ret)
-			return ret;
-
-		dev_info(&mc13xxx->spidev->dev, "%s: rev: %d.%d, "
+		dev_info(mc13xxx->dev, "%s: rev: %d.%d, "
 				"fin: %d, fab: %d, icid: %d/%d\n",
-				mc13xxx_chipname[*id],
+				mc13xxx_chipname[mc13xxx->ictype],
 				maskval(revision, MC13XXX_REVISION_REVFULL),
 				maskval(revision, MC13XXX_REVISION_REVMETAL),
 				maskval(revision, MC13XXX_REVISION_FIN),
@@ -536,26 +474,12 @@  static int mc13xxx_identify(struct mc13xxx *mc13xxx, enum mc13xxx_id *id)
 				maskval(revision, MC13XXX_REVISION_ICIDCODE));
 	}
 
-	if (*id != MC13XXX_ID_INVALID) {
-		const struct spi_device_id *devid =
-			spi_get_device_id(mc13xxx->spidev);
-		if (!devid || devid->driver_data != *id)
-			dev_warn(&mc13xxx->spidev->dev, "device id doesn't "
-					"match auto detection!\n");
-	}
-
-	return 0;
+	return (mc13xxx->ictype == MC13XXX_ID_INVALID) ? -ENODEV : 0;
 }
 
 static const char *mc13xxx_get_chipname(struct mc13xxx *mc13xxx)
 {
-	const struct spi_device_id *devid =
-		spi_get_device_id(mc13xxx->spidev);
-
-	if (!devid)
-		return NULL;
-
-	return mc13xxx_chipname[devid->driver_data];
+	return mc13xxx_chipname[mc13xxx->ictype];
 }
 
 #include <linux/mfd/mc13783.h>
@@ -563,7 +487,7 @@  static const char *mc13xxx_get_chipname(struct mc13xxx *mc13xxx)
 int mc13xxx_get_flags(struct mc13xxx *mc13xxx)
 {
 	struct mc13xxx_platform_data *pdata =
-		dev_get_platdata(&mc13xxx->spidev->dev);
+		dev_get_platdata(mc13xxx->dev);
 
 	return pdata->flags;
 }
@@ -601,7 +525,7 @@  int mc13783_adc_do_conversion(struct mc13783 *mc13783, unsigned int mode,
 	};
 	init_completion(&adcdone_data.done);
 
-	dev_dbg(&mc13xxx->spidev->dev, "%s\n", __func__);
+	dev_dbg(mc13xxx->dev, "%s\n", __func__);
 
 	mc13xxx_lock(mc13xxx);
 
@@ -643,7 +567,7 @@  int mc13783_adc_do_conversion(struct mc13783 *mc13783, unsigned int mode,
 		return -EINVAL;
 	}
 
-	dev_dbg(&mc13783->mc13xxx.spidev->dev, "%s: request irq\n", __func__);
+	dev_dbg(mc13783->mc13xxx.dev, "%s: request irq\n", __func__);
 	mc13xxx_irq_request(mc13xxx, MC13783_IRQ_ADCDONE,
 			mc13783_handler_adcdone, __func__, &adcdone_data);
 	mc13xxx_irq_ack(mc13xxx, MC13783_IRQ_ADCDONE);
@@ -701,7 +625,7 @@  static int mc13xxx_add_subdevice_pdata(struct mc13xxx *mc13xxx,
 	if (!cell.name)
 		return -ENOMEM;
 
-	return mfd_add_devices(&mc13xxx->spidev->dev, -1, &cell, 1, NULL, 0);
+	return mfd_add_devices(mc13xxx->dev, -1, &cell, 1, NULL, 0);
 }
 
 static int mc13xxx_add_subdevice(struct mc13xxx *mc13xxx, const char *format)
@@ -709,29 +633,16 @@  static int mc13xxx_add_subdevice(struct mc13xxx *mc13xxx, const char *format)
 	return mc13xxx_add_subdevice_pdata(mc13xxx, format, NULL, 0);
 }
 
-static int mc13xxx_probe(struct spi_device *spi)
+int mc13xxx_common_init(struct mc13xxx *mc13xxx,
+			struct mc13xxx_platform_data *pdata, int irq)
 {
-	struct mc13xxx *mc13xxx;
-	struct mc13xxx_platform_data *pdata = dev_get_platdata(&spi->dev);
-	enum mc13xxx_id id;
 	int ret;
 
-	mc13xxx = kzalloc(sizeof(*mc13xxx), GFP_KERNEL);
-	if (!mc13xxx)
-		return -ENOMEM;
-
-	dev_set_drvdata(&spi->dev, mc13xxx);
-	spi->mode = SPI_MODE_0 | SPI_CS_HIGH;
-	spi->bits_per_word = 32;
-	spi_setup(spi);
-
-	mc13xxx->spidev = spi;
-
 	mutex_init(&mc13xxx->lock);
 	mc13xxx_lock(mc13xxx);
 
-	ret = mc13xxx_identify(mc13xxx, &id);
-	if (ret || id == MC13XXX_ID_INVALID)
+	ret = mc13xxx_identify(mc13xxx);
+	if (ret)
 		goto err_revision;
 
 	/* mask all irqs */
@@ -743,14 +654,13 @@  static int mc13xxx_probe(struct spi_device *spi)
 	if (ret)
 		goto err_mask;
 
-	ret = request_threaded_irq(spi->irq, NULL, mc13xxx_irq_thread,
+	ret = request_threaded_irq(irq, NULL, mc13xxx_irq_thread,
 			IRQF_ONESHOT | IRQF_TRIGGER_HIGH, "mc13xxx", mc13xxx);
 
 	if (ret) {
 err_mask:
 err_revision:
 		mutex_unlock(&mc13xxx->lock);
-		dev_set_drvdata(&spi->dev, NULL);
 		kfree(mc13xxx);
 		return ret;
 	}
@@ -786,54 +696,7 @@  err_revision:
 
 	return 0;
 }
-
-static int __devexit mc13xxx_remove(struct spi_device *spi)
-{
-	struct mc13xxx *mc13xxx = dev_get_drvdata(&spi->dev);
-
-	free_irq(mc13xxx->spidev->irq, mc13xxx);
-
-	mfd_remove_devices(&spi->dev);
-
-	kfree(mc13xxx);
-
-	return 0;
-}
-
-static const struct spi_device_id mc13xxx_device_id[] = {
-	{
-		.name = "mc13783",
-		.driver_data = MC13XXX_ID_MC13783,
-	}, {
-		.name = "mc13892",
-		.driver_data = MC13XXX_ID_MC13892,
-	}, {
-		/* sentinel */
-	}
-};
-
-static struct spi_driver mc13xxx_driver = {
-	.id_table = mc13xxx_device_id,
-	.driver = {
-		.name = "mc13xxx",
-		.bus = &spi_bus_type,
-		.owner = THIS_MODULE,
-	},
-	.probe = mc13xxx_probe,
-	.remove = __devexit_p(mc13xxx_remove),
-};
-
-static int __init mc13xxx_init(void)
-{
-	return spi_register_driver(&mc13xxx_driver);
-}
-subsys_initcall(mc13xxx_init);
-
-static void __exit mc13xxx_exit(void)
-{
-	spi_unregister_driver(&mc13xxx_driver);
-}
-module_exit(mc13xxx_exit);
+EXPORT_SYMBOL_GPL(mc13xxx_common_init);
 
 MODULE_DESCRIPTION("Core driver for Freescale MC13XXX PMIC");
 MODULE_AUTHOR("Uwe Kleine-Koenig <[e-mail]>");
diff --git a/include/linux/mfd/mc13xxx.h b/include/linux/mfd/mc13xxx.h
index a1d391b..d7c18d7 100644
--- a/include/linux/mfd/mc13xxx.h
+++ b/include/linux/mfd/mc13xxx.h
@@ -11,7 +11,53 @@ 
 
 #include <linux/interrupt.h>
 
-struct mc13xxx;
+#define MC13XXX_IRQ_ADCDONE	0
+#define MC13XXX_IRQ_ADCBISDONE	1
+#define MC13XXX_IRQ_TS		2
+#define MC13XXX_IRQ_CHGDET	6
+#define MC13XXX_IRQ_CHGREV	8
+#define MC13XXX_IRQ_CHGSHORT	9
+#define MC13XXX_IRQ_CCCV	10
+#define MC13XXX_IRQ_CHGCURR	11
+#define MC13XXX_IRQ_BPON	12
+#define MC13XXX_IRQ_LOBATL	13
+#define MC13XXX_IRQ_LOBATH	14
+#define MC13XXX_IRQ_1HZ		24
+#define MC13XXX_IRQ_TODA	25
+#define MC13XXX_IRQ_SYSRST	30
+#define MC13XXX_IRQ_RTCRST	31
+#define MC13XXX_IRQ_PC		32
+#define MC13XXX_IRQ_WARM	33
+#define MC13XXX_IRQ_MEMHLD	34
+#define MC13XXX_IRQ_THWARNL	36
+#define MC13XXX_IRQ_THWARNH	37
+#define MC13XXX_IRQ_CLK		38
+
+#define MC13XXX_NUM_IRQ		46
+
+
+enum mc13xxx_id {
+	MC13XXX_ID_MC13783,
+	MC13XXX_ID_MC13892,
+	MC13XXX_ID_INVALID,
+};
+
+struct mc13xxx {
+	union {
+		struct spi_device *spidev;
+		struct i2c_client *i2cclient;
+	};
+	struct device *dev;
+	enum mc13xxx_id ictype;
+
+	struct mutex lock;
+
+	int (*read_dev)(struct mc13xxx *, unsigned int, u32 *);
+	int (*write_dev)(struct mc13xxx *, unsigned int, u32);
+
+	irq_handler_t irqhandler[MC13XXX_NUM_IRQ];
+	void *irqdata[MC13XXX_NUM_IRQ];
+};
 
 void mc13xxx_lock(struct mc13xxx *mc13xxx);
 void mc13xxx_unlock(struct mc13xxx *mc13xxx);
@@ -21,6 +67,11 @@  int mc13xxx_reg_write(struct mc13xxx *mc13xxx, unsigned int offset, u32 val);
 int mc13xxx_reg_rmw(struct mc13xxx *mc13xxx, unsigned int offset,
 		u32 mask, u32 val);
 
+struct mc13xxx_platform_data;
+
+int mc13xxx_common_init(struct mc13xxx *mc13xxx,
+			struct mc13xxx_platform_data *pdata, int irq);
+
 int mc13xxx_get_flags(struct mc13xxx *mc13xxx);
 
 int mc13xxx_irq_request(struct mc13xxx *mc13xxx, int irq,
@@ -37,30 +88,6 @@  int mc13xxx_irq_ack(struct mc13xxx *mc13xxx, int irq);
 
 int mc13xxx_get_flags(struct mc13xxx *mc13xxx);
 
-#define MC13XXX_IRQ_ADCDONE	0
-#define MC13XXX_IRQ_ADCBISDONE	1
-#define MC13XXX_IRQ_TS		2
-#define MC13XXX_IRQ_CHGDET	6
-#define MC13XXX_IRQ_CHGREV	8
-#define MC13XXX_IRQ_CHGSHORT	9
-#define MC13XXX_IRQ_CCCV	10
-#define MC13XXX_IRQ_CHGCURR	11
-#define MC13XXX_IRQ_BPON	12
-#define MC13XXX_IRQ_LOBATL	13
-#define MC13XXX_IRQ_LOBATH	14
-#define MC13XXX_IRQ_1HZ		24
-#define MC13XXX_IRQ_TODA	25
-#define MC13XXX_IRQ_SYSRST	30
-#define MC13XXX_IRQ_RTCRST	31
-#define MC13XXX_IRQ_PC		32
-#define MC13XXX_IRQ_WARM	33
-#define MC13XXX_IRQ_MEMHLD	34
-#define MC13XXX_IRQ_THWARNL	36
-#define MC13XXX_IRQ_THWARNH	37
-#define MC13XXX_IRQ_CLK		38
-
-#define MC13XXX_NUM_IRQ		46
-
 struct regulator_init_data;
 
 struct mc13xxx_regulator_init_data {