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[PATCH v6 2/4] dmaengine: dw: revisit data_width property

Started byAndy Shevchenko <andriy.shevchenko@linux.intel.com>
First post2016-04-25 14:40 +0200
Last post2016-04-27 10:40 +0200
Articles 6 — 4 participants

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  [PATCH v6 2/4] dmaengine: dw: revisit data_width property Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-04-25 14:40 +0200
    Re: [PATCH v6 2/4] dmaengine: dw: revisit data_width property Viresh Kumar <viresh.kumar@linaro.org> - 2016-04-27 08:50 +0200
      Re: [PATCH v6 2/4] dmaengine: dw: revisit data_width property Vinod Koul <vinod.koul@intel.com> - 2016-04-27 10:10 +0200
      Re: [PATCH v6 2/4] dmaengine: dw: revisit data_width property Andy Shevchenko <andy.shevchenko@gmail.com> - 2016-04-27 10:30 +0200
        Re: [PATCH v6 2/4] dmaengine: dw: revisit data_width property Viresh Kumar <viresh.kumar@linaro.org> - 2016-04-27 10:40 +0200
          Re: [PATCH v6 2/4] dmaengine: dw: revisit data_width property Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-04-27 10:40 +0200

#1386367 — [PATCH v6 2/4] dmaengine: dw: revisit data_width property

FromAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Date2016-04-25 14:40 +0200
Subject[PATCH v6 2/4] dmaengine: dw: revisit data_width property
Message-ID<rrNXZ-5VY-33@gated-at.bofh.it>
There are several changes are done here:

- Convert the property to be in bytes

Besides this is common practice for such property the use of a value in bytes
much more convenient than handling the encoded value.

- Rename data_width to data-width in the device tree bindings

- While here, replace dwc_fast_ffs() by __ffs()

The change leaves the support for old format as well just in case someone will
use a newer kernel with an old device tree blob.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 Documentation/devicetree/bindings/dma/snps-dma.txt |  6 ++--
 arch/arc/boot/dts/abilis_tb10x.dtsi                |  2 +-
 arch/arm/boot/dts/spear13xx.dtsi                   |  4 +--
 drivers/dma/dw/core.c                              | 42 ++++++----------------
 drivers/dma/dw/platform.c                          |  5 ++-
 include/linux/platform_data/dma-dw.h               |  2 +-
 6 files changed, 21 insertions(+), 40 deletions(-)

diff --git a/Documentation/devicetree/bindings/dma/snps-dma.txt b/Documentation/devicetree/bindings/dma/snps-dma.txt
index c99c1ff..544b9b9 100644
--- a/Documentation/devicetree/bindings/dma/snps-dma.txt
+++ b/Documentation/devicetree/bindings/dma/snps-dma.txt
@@ -13,8 +13,8 @@ Required properties:
 - chan_priority: priority of channels. 0 (default): increase from chan 0->n, 1:
   increase from chan n->0
 - block_size: Maximum block size supported by the controller
-- data_width: Maximum data width supported by hardware per AHB master
-  (0 - 8bits, 1 - 16bits, ..., 5 - 256bits)
+- data-width: Maximum data width supported by hardware per AHB master
+  (in bytes, power of 2)
 
 
 Optional properties:
@@ -38,7 +38,7 @@ Example:
 		chan_allocation_order = <1>;
 		chan_priority = <1>;
 		block_size = <0xfff>;
-		data_width = <3 3>;
+		data-width = <8 8>;
 	};
 
 DMA clients connected to the Designware DMA controller must use the format
diff --git a/arch/arc/boot/dts/abilis_tb10x.dtsi b/arch/arc/boot/dts/abilis_tb10x.dtsi
index 663671f2..de53f5c 100644
--- a/arch/arc/boot/dts/abilis_tb10x.dtsi
+++ b/arch/arc/boot/dts/abilis_tb10x.dtsi
@@ -126,7 +126,7 @@
 			chan_allocation_order = <0>;
 			chan_priority = <1>;
 			block_size = <0x7ff>;
-			data_width = <2>;
+			data-width = <4>;
 			clocks = <&ahb_clk>;
 			clock-names = "hclk";
 		};
diff --git a/arch/arm/boot/dts/spear13xx.dtsi b/arch/arm/boot/dts/spear13xx.dtsi
index 14594ce..449acf0 100644
--- a/arch/arm/boot/dts/spear13xx.dtsi
+++ b/arch/arm/boot/dts/spear13xx.dtsi
@@ -117,7 +117,7 @@
 			chan_priority = <1>;
 			block_size = <0xfff>;
 			dma-masters = <2>;
-			data_width = <3 3>;
+			data-width = <8 8>;
 		};
 
 		dma@eb000000 {
@@ -133,7 +133,7 @@
 			chan_allocation_order = <1>;
 			chan_priority = <1>;
 			block_size = <0xfff>;
-			data_width = <3 3>;
+			data-width = <8 8>;
 		};
 
 		fsmc: flash@b0000000 {
diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index 78522dc..992da25 100644
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -162,21 +162,6 @@ static void dwc_initialize(struct dw_dma_chan *dwc)
 
 /*----------------------------------------------------------------------*/
 
-static inline unsigned int dwc_fast_ffs(unsigned long long v)
-{
-	/*
-	 * We can be a lot more clever here, but this should take care
-	 * of the most common optimization.
-	 */
-	if (!(v & 7))
-		return 3;
-	else if (!(v & 3))
-		return 2;
-	else if (!(v & 1))
-		return 1;
-	return 0;
-}
-
 static inline void dwc_dump_chan_regs(struct dw_dma_chan *dwc)
 {
 	dev_err(chan2dev(&dwc->chan),
@@ -677,11 +662,12 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
 	struct dw_desc		*prev;
 	size_t			xfer_count;
 	size_t			offset;
+	u8			m_master = dwc->m_master;
 	unsigned int		src_width;
 	unsigned int		dst_width;
-	unsigned int		data_width;
+	unsigned int		data_width = dw->data_width[m_master];
 	u32			ctllo;
-	u8			lms = DWC_LLP_LMS(dwc->m_master);
+	u8			lms = DWC_LLP_LMS(m_master);
 
 	dev_vdbg(chan2dev(chan),
 			"%s: d%pad s%pad l0x%zx f0x%lx\n", __func__,
@@ -694,10 +680,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
 
 	dwc->direction = DMA_MEM_TO_MEM;
 
-	data_width = dw->data_width[dwc->m_master];
-
-	src_width = dst_width = min_t(unsigned int, data_width,
-				      dwc_fast_ffs(src | dest | len));
+	src_width = dst_width = __ffs(data_width | src | dest | len);
 
 	ctllo = DWC_DEFAULT_CTLLO(chan)
 			| DWC_CTLL_DST_WIDTH(dst_width)
@@ -757,11 +740,12 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 	struct dw_desc		*prev;
 	struct dw_desc		*first;
 	u32			ctllo;
-	u8			lms = DWC_LLP_LMS(dwc->m_master);
+	u8			m_master = dwc->m_master;
+	u8			lms = DWC_LLP_LMS(m_master);
 	dma_addr_t		reg;
 	unsigned int		reg_width;
 	unsigned int		mem_width;
-	unsigned int		data_width;
+	unsigned int		data_width = dw->data_width[m_master];
 	unsigned int		i;
 	struct scatterlist	*sg;
 	size_t			total_len = 0;
@@ -787,8 +771,6 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 		ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_M2P) :
 			DWC_CTLL_FC(DW_DMA_FC_D_M2P);
 
-		data_width = dw->data_width[dwc->m_master];
-
 		for_each_sg(sgl, sg, sg_len, i) {
 			struct dw_desc	*desc;
 			u32		len, dlen, mem;
@@ -796,8 +778,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 			mem = sg_dma_address(sg);
 			len = sg_dma_len(sg);
 
-			mem_width = min_t(unsigned int,
-					  data_width, dwc_fast_ffs(mem | len));
+			mem_width = __ffs(data_width | mem | len);
 
 slave_sg_todev_fill_desc:
 			desc = dwc_desc_get(dwc);
@@ -843,8 +824,6 @@ slave_sg_todev_fill_desc:
 		ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_P2M) :
 			DWC_CTLL_FC(DW_DMA_FC_D_P2M);
 
-		data_width = dw->data_width[dwc->m_master];
-
 		for_each_sg(sgl, sg, sg_len, i) {
 			struct dw_desc	*desc;
 			u32		len, dlen, mem;
@@ -852,8 +831,7 @@ slave_sg_todev_fill_desc:
 			mem = sg_dma_address(sg);
 			len = sg_dma_len(sg);
 
-			mem_width = min_t(unsigned int,
-					  data_width, dwc_fast_ffs(mem | len));
+			mem_width = __ffs(data_width | mem | len);
 
 slave_sg_fromdev_fill_desc:
 			desc = dwc_desc_get(dwc);
@@ -1500,7 +1478,7 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
 		pdata->nr_masters = (dw_params >> DW_PARAMS_NR_MASTER & 3) + 1;
 		for (i = 0; i < pdata->nr_masters; i++) {
 			pdata->data_width[i] =
-				(dw_params >> DW_PARAMS_DATA_WIDTH(i) & 3) + 2;
+				4 << (dw_params >> DW_PARAMS_DATA_WIDTH(i) & 3);
 		}
 		max_blk_size = dma_readl(dw, MAX_BLK_SIZE);
 
diff --git a/drivers/dma/dw/platform.c b/drivers/dma/dw/platform.c
index e65ebe5..2420fb7 100644
--- a/drivers/dma/dw/platform.c
+++ b/drivers/dma/dw/platform.c
@@ -138,9 +138,12 @@ dw_dma_parse_dt(struct platform_device *pdev)
 	if (!of_property_read_u32(np, "block_size", &tmp))
 		pdata->block_size = tmp;
 
-	if (!of_property_read_u32_array(np, "data_width", arr, nr_masters)) {
+	if (!of_property_read_u32_array(np, "data-width", arr, nr_masters)) {
 		for (tmp = 0; tmp < nr_masters; tmp++)
 			pdata->data_width[tmp] = arr[tmp];
+	} else if (!of_property_read_u32_array(np, "data_width", arr, nr_masters)) {
+		for (tmp = 0; tmp < nr_masters; tmp++)
+			pdata->data_width[tmp] = BIT(arr[tmp] & 0x07);
 	}
 
 	return pdata;
diff --git a/include/linux/platform_data/dma-dw.h b/include/linux/platform_data/dma-dw.h
index b881b97..ad76811 100644
--- a/include/linux/platform_data/dma-dw.h
+++ b/include/linux/platform_data/dma-dw.h
@@ -43,7 +43,7 @@ struct dw_dma_slave {
  * @block_size: Maximum block size supported by the controller
  * @nr_masters: Number of AHB masters supported by the controller
  * @data_width: Maximum data width supported by hardware per AHB master
- *		(0 - 8bits, 1 - 16bits, ..., 5 - 256bits)
+ *		(in bytes, power of 2)
  */
 struct dw_dma_platform_data {
 	unsigned int	nr_channels;
-- 
2.8.0.rc3

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#1388701

FromViresh Kumar <viresh.kumar@linaro.org>
Date2016-04-27 08:50 +0200
Message-ID<rsrsm-4Yn-7@gated-at.bofh.it>
In reply to#1386367
On 25-04-16, 15:35, Andy Shevchenko wrote:
> There are several changes are done here:
> 
> - Convert the property to be in bytes
> 
> Besides this is common practice for such property the use of a value in bytes
> much more convenient than handling the encoded value.
> 
> - Rename data_width to data-width in the device tree bindings
> 
> - While here, replace dwc_fast_ffs() by __ffs()
> 
> The change leaves the support for old format as well just in case someone will
> use a newer kernel with an old device tree blob.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  Documentation/devicetree/bindings/dma/snps-dma.txt |  6 ++--
>  arch/arc/boot/dts/abilis_tb10x.dtsi                |  2 +-
>  arch/arm/boot/dts/spear13xx.dtsi                   |  4 +--
>  drivers/dma/dw/core.c                              | 42 ++++++----------------
>  drivers/dma/dw/platform.c                          |  5 ++-
>  include/linux/platform_data/dma-dw.h               |  2 +-
>  6 files changed, 21 insertions(+), 40 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/dma/snps-dma.txt b/Documentation/devicetree/bindings/dma/snps-dma.txt
> index c99c1ff..544b9b9 100644
> --- a/Documentation/devicetree/bindings/dma/snps-dma.txt
> +++ b/Documentation/devicetree/bindings/dma/snps-dma.txt
> @@ -13,8 +13,8 @@ Required properties:
>  - chan_priority: priority of channels. 0 (default): increase from chan 0->n, 1:
>    increase from chan n->0
>  - block_size: Maximum block size supported by the controller
> -- data_width: Maximum data width supported by hardware per AHB master
> -  (0 - 8bits, 1 - 16bits, ..., 5 - 256bits)
> +- data-width: Maximum data width supported by hardware per AHB master
> +  (in bytes, power of 2)
>  
>  
>  Optional properties:
> @@ -38,7 +38,7 @@ Example:
>  		chan_allocation_order = <1>;
>  		chan_priority = <1>;
>  		block_size = <0xfff>;
> -		data_width = <3 3>;
> +		data-width = <8 8>;
>  	};

You broke backward compatibility with earlier DTs.

What's backward compatibility ?

Consider that the DT from an earlier version of kernel is part of the bootrom of
a SoC. Now that bootrom should work just fine with any new kernel version. i.e.
old DT + new kernels should always work.

-- 
viresh

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#1388767

FromVinod Koul <vinod.koul@intel.com>
Date2016-04-27 10:10 +0200
Message-ID<rssHN-6hy-29@gated-at.bofh.it>
In reply to#1388701
On Wed, Apr 27, 2016 at 12:13:17PM +0530, Viresh Kumar wrote:
> On 25-04-16, 15:35, Andy Shevchenko wrote:
> > There are several changes are done here:
> > 
> > - Convert the property to be in bytes
> > 
> > Besides this is common practice for such property the use of a value in bytes
> > much more convenient than handling the encoded value.
> > 
> > - Rename data_width to data-width in the device tree bindings
> > 
> > - While here, replace dwc_fast_ffs() by __ffs()
> > 
> > The change leaves the support for old format as well just in case someone will
> > use a newer kernel with an old device tree blob.
> > 
> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > ---
> >  Documentation/devicetree/bindings/dma/snps-dma.txt |  6 ++--
> >  arch/arc/boot/dts/abilis_tb10x.dtsi                |  2 +-
> >  arch/arm/boot/dts/spear13xx.dtsi                   |  4 +--
> >  drivers/dma/dw/core.c                              | 42 ++++++----------------
> >  drivers/dma/dw/platform.c                          |  5 ++-
> >  include/linux/platform_data/dma-dw.h               |  2 +-
> >  6 files changed, 21 insertions(+), 40 deletions(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/dma/snps-dma.txt b/Documentation/devicetree/bindings/dma/snps-dma.txt
> > index c99c1ff..544b9b9 100644
> > --- a/Documentation/devicetree/bindings/dma/snps-dma.txt
> > +++ b/Documentation/devicetree/bindings/dma/snps-dma.txt
> > @@ -13,8 +13,8 @@ Required properties:
> >  - chan_priority: priority of channels. 0 (default): increase from chan 0->n, 1:
> >    increase from chan n->0
> >  - block_size: Maximum block size supported by the controller
> > -- data_width: Maximum data width supported by hardware per AHB master
> > -  (0 - 8bits, 1 - 16bits, ..., 5 - 256bits)
> > +- data-width: Maximum data width supported by hardware per AHB master
> > +  (in bytes, power of 2)
> >  
> >  
> >  Optional properties:
> > @@ -38,7 +38,7 @@ Example:
> >  		chan_allocation_order = <1>;
> >  		chan_priority = <1>;
> >  		block_size = <0xfff>;
> > -		data_width = <3 3>;
> > +		data-width = <8 8>;
> >  	};
> 
> You broke backward compatibility with earlier DTs.
> 
> What's backward compatibility ?
> 
> Consider that the DT from an earlier version of kernel is part of the bootrom of
> a SoC. Now that bootrom should work just fine with any new kernel version. i.e.
> old DT + new kernels should always work.

And this is not fixed yet!.

-- 
~Vinod

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#1388779

FromAndy Shevchenko <andy.shevchenko@gmail.com>
Date2016-04-27 10:30 +0200
Message-ID<rst18-6uo-5@gated-at.bofh.it>
In reply to#1388701
On Wed, Apr 27, 2016 at 9:43 AM, Viresh Kumar <viresh.kumar@linaro.org> wrote:
> On 25-04-16, 15:35, Andy Shevchenko wrote:
>> There are several changes are done here:
>>
>> - Convert the property to be in bytes
>>
>> Besides this is common practice for such property the use of a value in bytes
>> much more convenient than handling the encoded value.
>>
>> - Rename data_width to data-width in the device tree bindings
>>
>> - While here, replace dwc_fast_ffs() by __ffs()
>>
>> The change leaves the support for old format as well just in case someone will
>> use a newer kernel with an old device tree blob.
>>
>> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>> ---
>>  Documentation/devicetree/bindings/dma/snps-dma.txt |  6 ++--
>>  arch/arc/boot/dts/abilis_tb10x.dtsi                |  2 +-
>>  arch/arm/boot/dts/spear13xx.dtsi                   |  4 +--
>>  drivers/dma/dw/core.c                              | 42 ++++++----------------
>>  drivers/dma/dw/platform.c                          |  5 ++-
>>  include/linux/platform_data/dma-dw.h               |  2 +-
>>  6 files changed, 21 insertions(+), 40 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/dma/snps-dma.txt b/Documentation/devicetree/bindings/dma/snps-dma.txt
>> index c99c1ff..544b9b9 100644
>> --- a/Documentation/devicetree/bindings/dma/snps-dma.txt
>> +++ b/Documentation/devicetree/bindings/dma/snps-dma.txt
>> @@ -13,8 +13,8 @@ Required properties:
>>  - chan_priority: priority of channels. 0 (default): increase from chan 0->n, 1:
>>    increase from chan n->0
>>  - block_size: Maximum block size supported by the controller
>> -- data_width: Maximum data width supported by hardware per AHB master
>> -  (0 - 8bits, 1 - 16bits, ..., 5 - 256bits)
>> +- data-width: Maximum data width supported by hardware per AHB master
>> +  (in bytes, power of 2)
>>
>>
>>  Optional properties:
>> @@ -38,7 +38,7 @@ Example:
>>               chan_allocation_order = <1>;
>>               chan_priority = <1>;
>>               block_size = <0xfff>;
>> -             data_width = <3 3>;
>> +             data-width = <8 8>;
>>       };
>
> You broke backward compatibility with earlier DTs.

How?

>
> What's backward compatibility ?
>
> Consider that the DT from an earlier version of kernel is part of the bootrom of
> a SoC. Now that bootrom should work just fine with any new kernel version. i.e.
> old DT + new kernels should always work.

Yes, the property name is slightly different as meaning.

If we find data-width property driver will use it, otherwise it takes
old name and converts variable to be in bytes in the driver.

-- 
With Best Regards,
Andy Shevchenko

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#1388782

FromViresh Kumar <viresh.kumar@linaro.org>
Date2016-04-27 10:40 +0200
Message-ID<rstaO-6zk-3@gated-at.bofh.it>
In reply to#1388779
On 27-04-16, 11:25, Andy Shevchenko wrote:
> On Wed, Apr 27, 2016 at 9:43 AM, Viresh Kumar <viresh.kumar@linaro.org> wrote:
> > On 25-04-16, 15:35, Andy Shevchenko wrote:
> >> There are several changes are done here:
> >>
> >> - Convert the property to be in bytes
> >>
> >> Besides this is common practice for such property the use of a value in bytes
> >> much more convenient than handling the encoded value.
> >>
> >> - Rename data_width to data-width in the device tree bindings
> >>
> >> - While here, replace dwc_fast_ffs() by __ffs()
> >>
> >> The change leaves the support for old format as well just in case someone will
> >> use a newer kernel with an old device tree blob.
> >>
> >> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> >> ---
> >>  Documentation/devicetree/bindings/dma/snps-dma.txt |  6 ++--
> >>  arch/arc/boot/dts/abilis_tb10x.dtsi                |  2 +-
> >>  arch/arm/boot/dts/spear13xx.dtsi                   |  4 +--
> >>  drivers/dma/dw/core.c                              | 42 ++++++----------------
> >>  drivers/dma/dw/platform.c                          |  5 ++-
> >>  include/linux/platform_data/dma-dw.h               |  2 +-
> >>  6 files changed, 21 insertions(+), 40 deletions(-)
> >>
> >> diff --git a/Documentation/devicetree/bindings/dma/snps-dma.txt b/Documentation/devicetree/bindings/dma/snps-dma.txt
> >> index c99c1ff..544b9b9 100644
> >> --- a/Documentation/devicetree/bindings/dma/snps-dma.txt
> >> +++ b/Documentation/devicetree/bindings/dma/snps-dma.txt
> >> @@ -13,8 +13,8 @@ Required properties:
> >>  - chan_priority: priority of channels. 0 (default): increase from chan 0->n, 1:
> >>    increase from chan n->0
> >>  - block_size: Maximum block size supported by the controller
> >> -- data_width: Maximum data width supported by hardware per AHB master
> >> -  (0 - 8bits, 1 - 16bits, ..., 5 - 256bits)
> >> +- data-width: Maximum data width supported by hardware per AHB master
> >> +  (in bytes, power of 2)
> >>
> >>
> >>  Optional properties:
> >> @@ -38,7 +38,7 @@ Example:
> >>               chan_allocation_order = <1>;
> >>               chan_priority = <1>;
> >>               block_size = <0xfff>;
> >> -             data_width = <3 3>;
> >> +             data-width = <8 8>;
> >>       };
> >
> > You broke backward compatibility with earlier DTs.
> 
> How?
> 
> >
> > What's backward compatibility ?
> >
> > Consider that the DT from an earlier version of kernel is part of the bootrom of
> > a SoC. Now that bootrom should work just fine with any new kernel version. i.e.
> > old DT + new kernels should always work.
> 
> Yes, the property name is slightly different as meaning.
> 
> If we find data-width property driver will use it, otherwise it takes
> old name and converts variable to be in bytes in the driver.

Oh, I missed that you renamed the property and taking care of both the
properties now. Sorry about that. So, you didn't break them for sure :)

But, the DT documentation doesn't contain the old property now but the code
does. I think you are required to keep the bindings currently supported by the
kernel in there. You can mark them deprecated, but can't remove them.

-- 
viresh

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#1388790

FromAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Date2016-04-27 10:40 +0200
Message-ID<rstaP-6zk-35@gated-at.bofh.it>
In reply to#1388782
On Wed, 2016-04-27 at 14:00 +0530, Viresh Kumar wrote:
> On 27-04-16, 11:25, Andy Shevchenko wrote:
> > 
> > -- data_width: Maximum data width supported by hardware per AHB
> > > > master
> > > > -  (0 - 8bits, 1 - 16bits, ..., 5 - 256bits)
> > > > +- data-width: Maximum data width supported by hardware per AHB
> > > > master
> > > > +  (in bytes, power of 2)

> 
> But, the DT documentation doesn't contain the old property now but the
> code
> does. I think you are required to keep the bindings currently
> supported by the
> kernel in there. You can mark them deprecated, but can't remove them.

This point I take, indeed.

Will update series soon. Thanks for review.

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy

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