Patchwork [v2,2/5] dma: mxs-dma: make platform_device_id more generic

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Submitter Dong Aisheng
Date May 4, 2012, 12:12 p.m.
Message ID <1336133539-13465-2-git-send-email-b29396@freescale.com>
Download mbox | patch
Permalink /patch/156886/
State New
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Comments

Dong Aisheng - May 4, 2012, 12:12 p.m.
From: Dong Aisheng <dong.aisheng@linaro.org>

Rewrite mxs_dma_is_apbh and mxs_dma_is_apbx in order to support
other SoCs like imx6q and reform the platform_device_id for the
better further dt support.

Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Huang Shijie <b32955@freescale.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>
---
ChangeLog v1->v2:
* remove using mxs_dma->version
* other minor fixes suggested by Shawn.
---
 arch/arm/mach-mxs/clock-mx23.c           |    4 +-
 arch/arm/mach-mxs/clock-mx28.c           |    4 +-
 arch/arm/mach-mxs/devices/platform-dma.c |   14 ++--
 drivers/dma/mxs-dma.c                    |  115 ++++++++++++++++++++---------
 include/linux/fsl/mxs-dma.h              |   12 +---
 5 files changed, 93 insertions(+), 56 deletions(-)
Marek Vasut - May 4, 2012, 12:15 p.m.
Dear Dong Aisheng,

> From: Dong Aisheng <dong.aisheng@linaro.org>
> 
> Rewrite mxs_dma_is_apbh and mxs_dma_is_apbx in order to support
> other SoCs like imx6q and reform the platform_device_id for the
> better further dt support.
> 
> Cc: Vinod Koul <vinod.koul@intel.com>
> Cc: Dan Williams <dan.j.williams@intel.com>
> Cc: Shawn Guo <shawn.guo@linaro.org>
> Cc: Sascha Hauer <s.hauer@pengutronix.de>
> Cc: Huang Shijie <b32955@freescale.com>
> Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
> Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>
> ---
> ChangeLog v1->v2:
> * remove using mxs_dma->version
> * other minor fixes suggested by Shawn.
> ---
>  arch/arm/mach-mxs/clock-mx23.c           |    4 +-
>  arch/arm/mach-mxs/clock-mx28.c           |    4 +-
>  arch/arm/mach-mxs/devices/platform-dma.c |   14 ++--
>  drivers/dma/mxs-dma.c                    |  115
> ++++++++++++++++++++--------- include/linux/fsl/mxs-dma.h              |  
> 12 +---
>  5 files changed, 93 insertions(+), 56 deletions(-)
> 
> diff --git a/arch/arm/mach-mxs/clock-mx23.c
> b/arch/arm/mach-mxs/clock-mx23.c index e3ac52c..1e67b85 100644
> --- a/arch/arm/mach-mxs/clock-mx23.c
> +++ b/arch/arm/mach-mxs/clock-mx23.c
> @@ -427,8 +427,8 @@ static struct clk_lookup lookups[] = {
>  	_REGISTER_CLOCK("duart", NULL, uart_clk)
>  	_REGISTER_CLOCK("mxs-auart.0", NULL, uart_clk)
>  	_REGISTER_CLOCK("rtc", NULL, rtc_clk)
> -	_REGISTER_CLOCK("mxs-dma-apbh", NULL, hbus_clk)
> -	_REGISTER_CLOCK("mxs-dma-apbx", NULL, xbus_clk)
> +	_REGISTER_CLOCK("imx23-dma-apbh", NULL, hbus_clk)
> +	_REGISTER_CLOCK("imx23-dma-apbx", NULL, xbus_clk)
>  	_REGISTER_CLOCK("mxs-mmc.0", NULL, ssp_clk)
>  	_REGISTER_CLOCK("mxs-mmc.1", NULL, ssp_clk)
>  	_REGISTER_CLOCK(NULL, "usb", usb_clk)
> diff --git a/arch/arm/mach-mxs/clock-mx28.c
> b/arch/arm/mach-mxs/clock-mx28.c index 1867a17..cca2cf7 100644
> --- a/arch/arm/mach-mxs/clock-mx28.c
> +++ b/arch/arm/mach-mxs/clock-mx28.c
> @@ -625,8 +625,8 @@ static struct clk_lookup lookups[] = {
>  	_REGISTER_CLOCK("mxs-auart.4", NULL, uart_clk)
>  	_REGISTER_CLOCK("rtc", NULL, rtc_clk)
>  	_REGISTER_CLOCK("pll2", NULL, pll2_clk)
> -	_REGISTER_CLOCK("mxs-dma-apbh", NULL, hbus_clk)
> -	_REGISTER_CLOCK("mxs-dma-apbx", NULL, xbus_clk)
> +	_REGISTER_CLOCK("imx28-dma-apbh", NULL, hbus_clk)
> +	_REGISTER_CLOCK("imx28-dma-apbx", NULL, xbus_clk)
>  	_REGISTER_CLOCK("mxs-mmc.0", NULL, ssp0_clk)
>  	_REGISTER_CLOCK("mxs-mmc.1", NULL, ssp1_clk)
>  	_REGISTER_CLOCK("mxs-mmc.2", NULL, ssp2_clk)
> diff --git a/arch/arm/mach-mxs/devices/platform-dma.c
> b/arch/arm/mach-mxs/devices/platform-dma.c index 6a0202b..aff4813 100644
> --- a/arch/arm/mach-mxs/devices/platform-dma.c
> +++ b/arch/arm/mach-mxs/devices/platform-dma.c
> @@ -32,17 +32,19 @@ static struct platform_device *__init mxs_add_dma(const
> char *devid,
> 
>  static int __init mxs_add_mxs_dma(void)
>  {
> -	char *apbh = "mxs-dma-apbh";
> -	char *apbx = "mxs-dma-apbx";
> +	char *mx23_apbh = "imx23-dma-apbh";
> +	char *mx23_apbx = "imx23-dma-apbx";
> +	char *mx28_apbh = "imx28-dma-apbh";
> +	char *mx28_apbx = "imx28-dma-apbx";

Wild guess ... but const char * won't hurt here ?

> 
>  	if (cpu_is_mx23()) {
> -		mxs_add_dma(apbh, MX23_APBH_DMA_BASE_ADDR);
> -		mxs_add_dma(apbx, MX23_APBX_DMA_BASE_ADDR);
> +		mxs_add_dma(mx23_apbh, MX23_APBH_DMA_BASE_ADDR);
> +		mxs_add_dma(mx23_apbx, MX23_APBX_DMA_BASE_ADDR);
>  	}
> 
>  	if (cpu_is_mx28()) {
> -		mxs_add_dma(apbh, MX28_APBH_DMA_BASE_ADDR);
> -		mxs_add_dma(apbx, MX28_APBX_DMA_BASE_ADDR);
> +		mxs_add_dma(mx28_apbh, MX28_APBH_DMA_BASE_ADDR);
> +		mxs_add_dma(mx28_apbx, MX28_APBX_DMA_BASE_ADDR);
>  	}
> 
>  	return 0;
> diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
> index 0fefdd3..d8505d3 100644
> --- a/drivers/dma/mxs-dma.c
> +++ b/drivers/dma/mxs-dma.c
> @@ -35,12 +35,8 @@
>   * dma can program the controller registers of peripheral devices.
>   */
> 
> -#define MXS_DMA_APBH		0
> -#define MXS_DMA_APBX		1
> -#define dma_is_apbh()		(mxs_dma->dev_id == MXS_DMA_APBH)
> -
> -#define APBH_VERSION_LATEST	3
> -#define apbh_is_old()		(mxs_dma->version < APBH_VERSION_LATEST)
> +#define dma_is_apbh()		(mxs_dma->type == MXS_DMA_APBH)
> +#define apbh_is_old()		(mxs_dma->dev_id == IMX23_DMA)
> 
>  #define HW_APBHX_CTRL0				0x000
>  #define BM_APBH_CTRL0_APB_BURST8_EN		(1 << 29)
> @@ -50,9 +46,6 @@
>  #define HW_APBHX_CTRL2				0x020
>  #define HW_APBHX_CHANNEL_CTRL			0x030
>  #define BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL	16
> -#define HW_APBH_VERSION				(cpu_is_mx23() ? 0x3f0 : 
0x800)
> -#define HW_APBX_VERSION				0x800
> -#define BP_APBHX_VERSION_MAJOR			24
>  #define HW_APBHX_CHn_NXTCMDAR(n) \
>  	(((dma_is_apbh() && apbh_is_old()) ? 0x050 : 0x110) + (n) * 0x70)
>  #define HW_APBHX_CHn_SEMA(n) \
> @@ -120,9 +113,19 @@ struct mxs_dma_chan {
>  #define MXS_DMA_CHANNELS		16
>  #define MXS_DMA_CHANNELS_MASK		0xffff
> 
> +enum mxs_dma_devtype {
> +	MXS_DMA_APBH,
> +	MXS_DMA_APBX,
> +};
> +
> +enum mxs_dma_id {
> +	IMX23_DMA,
> +	IMX28_DMA,
> +};
> +
>  struct mxs_dma_engine {
> -	int				dev_id;
> -	unsigned int			version;
> +	enum mxs_dma_id			dev_id;
> +	enum mxs_dma_devtype		type;
>  	void __iomem			*base;
>  	struct clk			*clk;
>  	struct dma_device		dma_device;
> @@ -130,6 +133,66 @@ struct mxs_dma_engine {
>  	struct mxs_dma_chan		mxs_chans[MXS_DMA_CHANNELS];
>  };
> 
> +struct mxs_dma_type {
> +	enum mxs_dma_id id;
> +	enum mxs_dma_devtype type;
> +};
> +
> +static struct mxs_dma_type mxs_dma_types[] = {
> +	{
> +		.id = IMX23_DMA,
> +		.type = MXS_DMA_APBH,
> +	}, {
> +		.id = IMX23_DMA,
> +		.type = MXS_DMA_APBX,
> +	}, {
> +		.id = IMX28_DMA,
> +		.type = MXS_DMA_APBH,
> +	}, {
> +		.id = IMX28_DMA,
> +		.type = MXS_DMA_APBX,
> +	}
> +};
> +
> +static struct platform_device_id mxs_dma_ids[] = {
> +	{
> +		.name = "imx23-dma-apbh",
> +		.driver_data = (kernel_ulong_t) &mxs_dma_types[0],
> +	}, {
> +		.name = "imx23-dma-apbx",
> +		.driver_data = (kernel_ulong_t) &mxs_dma_types[1],
> +	}, {
> +		.name = "imx28-dma-apbh",
> +		.driver_data = (kernel_ulong_t) &mxs_dma_types[2],
> +	}, {
> +		.name = "imx28-dma-apbx",
> +		.driver_data = (kernel_ulong_t) &mxs_dma_types[3],
> +	}, {
> +		/* end of list */
> +	}
> +};
> +
> +static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
> +{
> +	return container_of(chan, struct mxs_dma_chan, chan);
> +}
> +
> +int mxs_dma_is_apbh(struct dma_chan *chan)
> +{
> +	struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
> +	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;

Do you need the above here ? :)

> +
> +	return dma_is_apbh();
> +}
> +
> +int mxs_dma_is_apbx(struct dma_chan *chan)
> +{
> +	struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
> +	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
> +

Dtto ?

> +	return !dma_is_apbh();
> +}
> +
>  static void mxs_dma_reset_chan(struct mxs_dma_chan *mxs_chan)
>  {
>  	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
> @@ -193,11 +256,6 @@ static void mxs_dma_resume_chan(struct mxs_dma_chan
> *mxs_chan) mxs_chan->status = DMA_IN_PROGRESS;
>  }
> 
> -static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
> -{
> -	return container_of(chan, struct mxs_dma_chan, chan);
> -}
> -
>  static dma_cookie_t mxs_dma_tx_submit(struct dma_async_tx_descriptor *tx)
>  {
>  	return dma_cookie_assign(tx);
> @@ -570,12 +628,6 @@ static int __init mxs_dma_init(struct mxs_dma_engine
> *mxs_dma) if (ret)
>  		goto err_out;
> 
> -	/* only major version matters */
> -	mxs_dma->version = readl(mxs_dma->base +
> -				((mxs_dma->dev_id == MXS_DMA_APBX) ?
> -				HW_APBX_VERSION : HW_APBH_VERSION)) >>
> -				BP_APBHX_VERSION_MAJOR;
> -
>  	/* enable apbh burst */
>  	if (dma_is_apbh()) {
>  		writel(BM_APBH_CTRL0_APB_BURST_EN,
> @@ -597,6 +649,8 @@ static int __init mxs_dma_probe(struct platform_device
> *pdev) {
>  	const struct platform_device_id *id_entry =
>  				platform_get_device_id(pdev);
> +	const struct mxs_dma_type *dma_type =
> +			(struct mxs_dma_type *)id_entry->driver_data;
>  	struct mxs_dma_engine *mxs_dma;
>  	struct resource *iores;
>  	int ret, i;
> @@ -605,7 +659,8 @@ static int __init mxs_dma_probe(struct platform_device
> *pdev) if (!mxs_dma)
>  		return -ENOMEM;
> 
> -	mxs_dma->dev_id = id_entry->driver_data;
> +	mxs_dma->dev_id = dma_type->id;
> +	mxs_dma->type = dma_type->type;
> 
>  	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> 
> @@ -688,23 +743,11 @@ err_request_region:
>  	return ret;
>  }
> 
> -static struct platform_device_id mxs_dma_type[] = {
> -	{
> -		.name = "mxs-dma-apbh",
> -		.driver_data = MXS_DMA_APBH,
> -	}, {
> -		.name = "mxs-dma-apbx",
> -		.driver_data = MXS_DMA_APBX,
> -	}, {
> -		/* end of list */
> -	}
> -};
> -
>  static struct platform_driver mxs_dma_driver = {
>  	.driver		= {
>  		.name	= "mxs-dma",
>  	},
> -	.id_table	= mxs_dma_type,
> +	.id_table	= mxs_dma_ids,
>  };
> 
>  static int __init mxs_dma_module_init(void)
> diff --git a/include/linux/fsl/mxs-dma.h b/include/linux/fsl/mxs-dma.h
> index 203d7c4..55d8702 100644
> --- a/include/linux/fsl/mxs-dma.h
> +++ b/include/linux/fsl/mxs-dma.h
> @@ -15,14 +15,6 @@ struct mxs_dma_data {
>  	int chan_irq;
>  };
> 
> -static inline int mxs_dma_is_apbh(struct dma_chan *chan)
> -{
> -	return !strcmp(dev_name(chan->device->dev), "mxs-dma-apbh");
> -}
> -
> -static inline int mxs_dma_is_apbx(struct dma_chan *chan)
> -{
> -	return !strcmp(dev_name(chan->device->dev), "mxs-dma-apbx");
> -}
> -
> +extern int mxs_dma_is_apbh(struct dma_chan *chan);
> +extern int mxs_dma_is_apbx(struct dma_chan *chan);
>  #endif /* __MACH_MXS_DMA_H__ */
Shawn Guo - May 4, 2012, 2:34 p.m.
On Fri, May 04, 2012 at 02:15:03PM +0200, Marek Vasut wrote:
> >  static int __init mxs_add_mxs_dma(void)
> >  {
> > -	char *apbh = "mxs-dma-apbh";
> > -	char *apbx = "mxs-dma-apbx";
> > +	char *mx23_apbh = "imx23-dma-apbh";
> > +	char *mx23_apbx = "imx23-dma-apbx";
> > +	char *mx28_apbh = "imx28-dma-apbh";
> > +	char *mx28_apbx = "imx28-dma-apbx";
> 
> Wild guess ... but const char * won't hurt here ?
> 
Right.  I guess it just followed how the existing code looks like.
Considering this whole function will be removed patch #4, it should
not be a big problem, I guess.

> > -#define MXS_DMA_APBH		0
> > -#define MXS_DMA_APBX		1
> > -#define dma_is_apbh()		(mxs_dma->dev_id == MXS_DMA_APBH)
> > -
> > -#define APBH_VERSION_LATEST	3
> > -#define apbh_is_old()		(mxs_dma->version < APBH_VERSION_LATEST)
> > +#define dma_is_apbh()		(mxs_dma->type == MXS_DMA_APBH)
> > +#define apbh_is_old()		(mxs_dma->dev_id == IMX23_DMA)
> > 
...
> > +int mxs_dma_is_apbh(struct dma_chan *chan)
> > +{
> > +	struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
> > +	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
> 
> Do you need the above here ? :)
> 
I have to confess it's my bad.  I made the code hard to read when I
created the driver.  The dma_is_apbh() should really takes mxs_dma
as a parameter than hiding it in the macro.

While I agree this is something should be improved, it may be better
to do it in another patch?

> > +
> > +	return dma_is_apbh();
> > +}
Marek Vasut - May 5, 2012, 1:12 p.m.
Dear Shawn Guo,

> On Fri, May 04, 2012 at 02:15:03PM +0200, Marek Vasut wrote:
> > >  static int __init mxs_add_mxs_dma(void)
> > >  {
> > > 
> > > -	char *apbh = "mxs-dma-apbh";
> > > -	char *apbx = "mxs-dma-apbx";
> > > +	char *mx23_apbh = "imx23-dma-apbh";
> > > +	char *mx23_apbx = "imx23-dma-apbx";
> > > +	char *mx28_apbh = "imx28-dma-apbh";
> > > +	char *mx28_apbx = "imx28-dma-apbx";
> > 
> > Wild guess ... but const char * won't hurt here ?
> 
> Right.  I guess it just followed how the existing code looks like.
> Considering this whole function will be removed patch #4, it should
> not be a big problem, I guess.

Can't the patches be reordered then to avoid adding this altogether?

> > > -#define MXS_DMA_APBH		0
> > > -#define MXS_DMA_APBX		1
> > > -#define dma_is_apbh()		(mxs_dma->dev_id == MXS_DMA_APBH)
> > > -
> > > -#define APBH_VERSION_LATEST	3
> > > -#define apbh_is_old()		(mxs_dma->version < APBH_VERSION_LATEST)
> > > +#define dma_is_apbh()		(mxs_dma->type == MXS_DMA_APBH)
> > > +#define apbh_is_old()		(mxs_dma->dev_id == IMX23_DMA)
> 
> ...
> 
> > > +int mxs_dma_is_apbh(struct dma_chan *chan)
> > > +{
> > > +	struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
> > > +	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
> > 
> > Do you need the above here ? :)
> 
> I have to confess it's my bad.  I made the code hard to read when I
> created the driver.  The dma_is_apbh() should really takes mxs_dma
> as a parameter than hiding it in the macro.
> 
> While I agree this is something should be improved, it may be better
> to do it in another patch?

You don't have to add dead code in this patch and re-add it when needed. Or fix 
the macro to take the parameter then, though I don't understand why you'd want 
to take it and then hide it.

> > > +
> > > +	return dma_is_apbh();
> > > +}

Best regards,
Marek Vasut
Shawn Guo - May 5, 2012, 1:25 p.m.
On 5 May 2012 21:12, Marek Vasut <marex@denx.de> wrote:
> Can't the patches be reordered then to avoid adding this altogether?
>
Maybe.  But I do not think it's really worth the effort.

> You don't have to add dead code in this patch and re-add it when needed. Or fix
> the macro to take the parameter then, though I don't understand why you'd want
> to take it and then hide it.
>
I do not completely understand the comment.  My point is the problem
is in the existing code.  It's not introduced by Dong's patch.  The
problem should be fixed in another patch, and we do not want to do
several things in one patch.

Regards,
Shawn
Marek Vasut - May 5, 2012, 2:32 p.m.
Dear Shawn Guo,

> On 5 May 2012 21:12, Marek Vasut <marex@denx.de> wrote:
> > Can't the patches be reordered then to avoid adding this altogether?
> 
> Maybe.  But I do not think it's really worth the effort.
> 
> > You don't have to add dead code in this patch and re-add it when needed.
> > Or fix the macro to take the parameter then, though I don't understand
> > why you'd want to take it and then hide it.
> 
> I do not completely understand the comment.  My point is the problem
> is in the existing code.  It's not introduced by Dong's patch.  The
> problem should be fixed in another patch, and we do not want to do
> several things in one patch.

Then order such a patch before Dong's series then? It'd all be clear, without 
compromises.

> 
> Regards,
> Shawn

Best regards,
Marek Vasut
Shawn Guo - May 7, 2012, 3:52 a.m.
On 7 May 2012 11:55, Dong Aisheng <aisheng.dong@freescale.com> wrote:
> Hmm, although not a big issue, but i can re-oder it to make most people happy with
> the patch.
>
I will take care of it, since I will need to rebase the series on
mxs-common-clk series anyway.  Hopefully, I can get it out today.

Regard,
Shawn
Dong Aisheng - May 7, 2012, 3:55 a.m.
On Sat, May 05, 2012 at 10:32:14PM +0800, Marek Vasut wrote:
> Dear Shawn Guo,
> 
> > On 5 May 2012 21:12, Marek Vasut <marex@denx.de> wrote:
> > > Can't the patches be reordered then to avoid adding this altogether?
> > 
> > Maybe.  But I do not think it's really worth the effort.
> > 
> > > You don't have to add dead code in this patch and re-add it when needed.
> > > Or fix the macro to take the parameter then, though I don't understand
> > > why you'd want to take it and then hide it.
> > 
> > I do not completely understand the comment.  My point is the problem
> > is in the existing code.  It's not introduced by Dong's patch.  The
> > problem should be fixed in another patch, and we do not want to do
> > several things in one patch.
> 
> Then order such a patch before Dong's series then? It'd all be clear, without 
> compromises.
> 
Hmm, although not a big issue, but i can re-oder it to make most people happy with
the patch.

Thanks

Regards
Dong Aisheng
Marek Vasut - May 7, 2012, 4:07 a.m.
Dear Shawn Guo,

> On 7 May 2012 11:55, Dong Aisheng <aisheng.dong@freescale.com> wrote:
> > Hmm, although not a big issue, but i can re-oder it to make most people
> > happy with the patch.
> 
> I will take care of it, since I will need to rebase the series on
> mxs-common-clk series anyway.  Hopefully, I can get it out today.

Why do I get the feeling I'm the bad guy here ? :-)

> 
> Regard,
> Shawn

Best regards,
Marek Vasut
Shawn Guo - May 7, 2012, 4:14 a.m.
On 7 May 2012 12:07, Marek Vasut <marex@denx.de> wrote:
> Why do I get the feeling I'm the bad guy here ? :-)
>
The "bad" buy is asking for good code, so welcome :)

Regards,
Shawn

Patch

diff --git a/arch/arm/mach-mxs/clock-mx23.c b/arch/arm/mach-mxs/clock-mx23.c
index e3ac52c..1e67b85 100644
--- a/arch/arm/mach-mxs/clock-mx23.c
+++ b/arch/arm/mach-mxs/clock-mx23.c
@@ -427,8 +427,8 @@  static struct clk_lookup lookups[] = {
 	_REGISTER_CLOCK("duart", NULL, uart_clk)
 	_REGISTER_CLOCK("mxs-auart.0", NULL, uart_clk)
 	_REGISTER_CLOCK("rtc", NULL, rtc_clk)
-	_REGISTER_CLOCK("mxs-dma-apbh", NULL, hbus_clk)
-	_REGISTER_CLOCK("mxs-dma-apbx", NULL, xbus_clk)
+	_REGISTER_CLOCK("imx23-dma-apbh", NULL, hbus_clk)
+	_REGISTER_CLOCK("imx23-dma-apbx", NULL, xbus_clk)
 	_REGISTER_CLOCK("mxs-mmc.0", NULL, ssp_clk)
 	_REGISTER_CLOCK("mxs-mmc.1", NULL, ssp_clk)
 	_REGISTER_CLOCK(NULL, "usb", usb_clk)
diff --git a/arch/arm/mach-mxs/clock-mx28.c b/arch/arm/mach-mxs/clock-mx28.c
index 1867a17..cca2cf7 100644
--- a/arch/arm/mach-mxs/clock-mx28.c
+++ b/arch/arm/mach-mxs/clock-mx28.c
@@ -625,8 +625,8 @@  static struct clk_lookup lookups[] = {
 	_REGISTER_CLOCK("mxs-auart.4", NULL, uart_clk)
 	_REGISTER_CLOCK("rtc", NULL, rtc_clk)
 	_REGISTER_CLOCK("pll2", NULL, pll2_clk)
-	_REGISTER_CLOCK("mxs-dma-apbh", NULL, hbus_clk)
-	_REGISTER_CLOCK("mxs-dma-apbx", NULL, xbus_clk)
+	_REGISTER_CLOCK("imx28-dma-apbh", NULL, hbus_clk)
+	_REGISTER_CLOCK("imx28-dma-apbx", NULL, xbus_clk)
 	_REGISTER_CLOCK("mxs-mmc.0", NULL, ssp0_clk)
 	_REGISTER_CLOCK("mxs-mmc.1", NULL, ssp1_clk)
 	_REGISTER_CLOCK("mxs-mmc.2", NULL, ssp2_clk)
diff --git a/arch/arm/mach-mxs/devices/platform-dma.c b/arch/arm/mach-mxs/devices/platform-dma.c
index 6a0202b..aff4813 100644
--- a/arch/arm/mach-mxs/devices/platform-dma.c
+++ b/arch/arm/mach-mxs/devices/platform-dma.c
@@ -32,17 +32,19 @@  static struct platform_device *__init mxs_add_dma(const char *devid,
 
 static int __init mxs_add_mxs_dma(void)
 {
-	char *apbh = "mxs-dma-apbh";
-	char *apbx = "mxs-dma-apbx";
+	char *mx23_apbh = "imx23-dma-apbh";
+	char *mx23_apbx = "imx23-dma-apbx";
+	char *mx28_apbh = "imx28-dma-apbh";
+	char *mx28_apbx = "imx28-dma-apbx";
 
 	if (cpu_is_mx23()) {
-		mxs_add_dma(apbh, MX23_APBH_DMA_BASE_ADDR);
-		mxs_add_dma(apbx, MX23_APBX_DMA_BASE_ADDR);
+		mxs_add_dma(mx23_apbh, MX23_APBH_DMA_BASE_ADDR);
+		mxs_add_dma(mx23_apbx, MX23_APBX_DMA_BASE_ADDR);
 	}
 
 	if (cpu_is_mx28()) {
-		mxs_add_dma(apbh, MX28_APBH_DMA_BASE_ADDR);
-		mxs_add_dma(apbx, MX28_APBX_DMA_BASE_ADDR);
+		mxs_add_dma(mx28_apbh, MX28_APBH_DMA_BASE_ADDR);
+		mxs_add_dma(mx28_apbx, MX28_APBX_DMA_BASE_ADDR);
 	}
 
 	return 0;
diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
index 0fefdd3..d8505d3 100644
--- a/drivers/dma/mxs-dma.c
+++ b/drivers/dma/mxs-dma.c
@@ -35,12 +35,8 @@ 
  * dma can program the controller registers of peripheral devices.
  */
 
-#define MXS_DMA_APBH		0
-#define MXS_DMA_APBX		1
-#define dma_is_apbh()		(mxs_dma->dev_id == MXS_DMA_APBH)
-
-#define APBH_VERSION_LATEST	3
-#define apbh_is_old()		(mxs_dma->version < APBH_VERSION_LATEST)
+#define dma_is_apbh()		(mxs_dma->type == MXS_DMA_APBH)
+#define apbh_is_old()		(mxs_dma->dev_id == IMX23_DMA)
 
 #define HW_APBHX_CTRL0				0x000
 #define BM_APBH_CTRL0_APB_BURST8_EN		(1 << 29)
@@ -50,9 +46,6 @@ 
 #define HW_APBHX_CTRL2				0x020
 #define HW_APBHX_CHANNEL_CTRL			0x030
 #define BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL	16
-#define HW_APBH_VERSION				(cpu_is_mx23() ? 0x3f0 : 0x800)
-#define HW_APBX_VERSION				0x800
-#define BP_APBHX_VERSION_MAJOR			24
 #define HW_APBHX_CHn_NXTCMDAR(n) \
 	(((dma_is_apbh() && apbh_is_old()) ? 0x050 : 0x110) + (n) * 0x70)
 #define HW_APBHX_CHn_SEMA(n) \
@@ -120,9 +113,19 @@  struct mxs_dma_chan {
 #define MXS_DMA_CHANNELS		16
 #define MXS_DMA_CHANNELS_MASK		0xffff
 
+enum mxs_dma_devtype {
+	MXS_DMA_APBH,
+	MXS_DMA_APBX,
+};
+
+enum mxs_dma_id {
+	IMX23_DMA,
+	IMX28_DMA,
+};
+
 struct mxs_dma_engine {
-	int				dev_id;
-	unsigned int			version;
+	enum mxs_dma_id			dev_id;
+	enum mxs_dma_devtype		type;
 	void __iomem			*base;
 	struct clk			*clk;
 	struct dma_device		dma_device;
@@ -130,6 +133,66 @@  struct mxs_dma_engine {
 	struct mxs_dma_chan		mxs_chans[MXS_DMA_CHANNELS];
 };
 
+struct mxs_dma_type {
+	enum mxs_dma_id id;
+	enum mxs_dma_devtype type;
+};
+
+static struct mxs_dma_type mxs_dma_types[] = {
+	{
+		.id = IMX23_DMA,
+		.type = MXS_DMA_APBH,
+	}, {
+		.id = IMX23_DMA,
+		.type = MXS_DMA_APBX,
+	}, {
+		.id = IMX28_DMA,
+		.type = MXS_DMA_APBH,
+	}, {
+		.id = IMX28_DMA,
+		.type = MXS_DMA_APBX,
+	}
+};
+
+static struct platform_device_id mxs_dma_ids[] = {
+	{
+		.name = "imx23-dma-apbh",
+		.driver_data = (kernel_ulong_t) &mxs_dma_types[0],
+	}, {
+		.name = "imx23-dma-apbx",
+		.driver_data = (kernel_ulong_t) &mxs_dma_types[1],
+	}, {
+		.name = "imx28-dma-apbh",
+		.driver_data = (kernel_ulong_t) &mxs_dma_types[2],
+	}, {
+		.name = "imx28-dma-apbx",
+		.driver_data = (kernel_ulong_t) &mxs_dma_types[3],
+	}, {
+		/* end of list */
+	}
+};
+
+static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
+{
+	return container_of(chan, struct mxs_dma_chan, chan);
+}
+
+int mxs_dma_is_apbh(struct dma_chan *chan)
+{
+	struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
+	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
+
+	return dma_is_apbh();
+}
+
+int mxs_dma_is_apbx(struct dma_chan *chan)
+{
+	struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
+	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
+
+	return !dma_is_apbh();
+}
+
 static void mxs_dma_reset_chan(struct mxs_dma_chan *mxs_chan)
 {
 	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
@@ -193,11 +256,6 @@  static void mxs_dma_resume_chan(struct mxs_dma_chan *mxs_chan)
 	mxs_chan->status = DMA_IN_PROGRESS;
 }
 
-static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
-{
-	return container_of(chan, struct mxs_dma_chan, chan);
-}
-
 static dma_cookie_t mxs_dma_tx_submit(struct dma_async_tx_descriptor *tx)
 {
 	return dma_cookie_assign(tx);
@@ -570,12 +628,6 @@  static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma)
 	if (ret)
 		goto err_out;
 
-	/* only major version matters */
-	mxs_dma->version = readl(mxs_dma->base +
-				((mxs_dma->dev_id == MXS_DMA_APBX) ?
-				HW_APBX_VERSION : HW_APBH_VERSION)) >>
-				BP_APBHX_VERSION_MAJOR;
-
 	/* enable apbh burst */
 	if (dma_is_apbh()) {
 		writel(BM_APBH_CTRL0_APB_BURST_EN,
@@ -597,6 +649,8 @@  static int __init mxs_dma_probe(struct platform_device *pdev)
 {
 	const struct platform_device_id *id_entry =
 				platform_get_device_id(pdev);
+	const struct mxs_dma_type *dma_type =
+			(struct mxs_dma_type *)id_entry->driver_data;
 	struct mxs_dma_engine *mxs_dma;
 	struct resource *iores;
 	int ret, i;
@@ -605,7 +659,8 @@  static int __init mxs_dma_probe(struct platform_device *pdev)
 	if (!mxs_dma)
 		return -ENOMEM;
 
-	mxs_dma->dev_id = id_entry->driver_data;
+	mxs_dma->dev_id = dma_type->id;
+	mxs_dma->type = dma_type->type;
 
 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 
@@ -688,23 +743,11 @@  err_request_region:
 	return ret;
 }
 
-static struct platform_device_id mxs_dma_type[] = {
-	{
-		.name = "mxs-dma-apbh",
-		.driver_data = MXS_DMA_APBH,
-	}, {
-		.name = "mxs-dma-apbx",
-		.driver_data = MXS_DMA_APBX,
-	}, {
-		/* end of list */
-	}
-};
-
 static struct platform_driver mxs_dma_driver = {
 	.driver		= {
 		.name	= "mxs-dma",
 	},
-	.id_table	= mxs_dma_type,
+	.id_table	= mxs_dma_ids,
 };
 
 static int __init mxs_dma_module_init(void)
diff --git a/include/linux/fsl/mxs-dma.h b/include/linux/fsl/mxs-dma.h
index 203d7c4..55d8702 100644
--- a/include/linux/fsl/mxs-dma.h
+++ b/include/linux/fsl/mxs-dma.h
@@ -15,14 +15,6 @@  struct mxs_dma_data {
 	int chan_irq;
 };
 
-static inline int mxs_dma_is_apbh(struct dma_chan *chan)
-{
-	return !strcmp(dev_name(chan->device->dev), "mxs-dma-apbh");
-}
-
-static inline int mxs_dma_is_apbx(struct dma_chan *chan)
-{
-	return !strcmp(dev_name(chan->device->dev), "mxs-dma-apbx");
-}
-
+extern int mxs_dma_is_apbh(struct dma_chan *chan);
+extern int mxs_dma_is_apbx(struct dma_chan *chan);
 #endif /* __MACH_MXS_DMA_H__ */