[PATCH 0/4] Fix backlight on Armadillo 800 EVA

[PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Laurent Pinchart]

Hello,

Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight: Add power
supply support") added a mandatory power supply for the PWM backlight,
resulting in broken backlight on the Armadillo board. This patch set fixes the
issue by adding power supplies to board code and DT, and adds proper handling
of the panel enable signal through the PWM backlight enable GPIO.

Patch 1/4 fixes a v3.13 regression. Strictly speaking patch 3/4 is as well,
but the backlight was broken anyway with DT due to the enable GPIO not being
handled at all, so there's no need to push it to v3.13.

Laurent Pinchart (4):
  ARM: shmobile: armadillo: Add PWM backlight power supply
  ARM: shmobile: armadillo: Set backlight enable GPIO
  ARM: shmobile: armadillo: dts: Add PWM backlight power supply
  ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO

 arch/arm/boot/dts/r8a7740-armadillo800eva-reference.dts | 11 +++++++++++
 arch/arm/mach-shmobile/board-armadillo800eva.c          | 12 ++++++++----
 2 files changed, 19 insertions(+), 4 deletions(-)

-- 
Regards,

Laurent Pinchart

Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Thierry Reding]

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On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> Hello,
> 
> Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight: Add power
> supply support") added a mandatory power supply for the PWM backlight,
> resulting in broken backlight on the Armadillo board. This patch set fixes the
> issue by adding power supplies to board code and DT, and adds proper handling
> of the panel enable signal through the PWM backlight enable GPIO.
> 
> Patch 1/4 fixes a v3.13 regression.

Actually there should be no regression at all here. The regulator core
handles this case by providing a dummy if the property hasn't been
specified in DT.

> Strictly speaking patch 3/4 is as well, but the backlight was broken
> anyway with DT due to the enable GPIO not being handled at all, so
> there's no need to push it to v3.13.

If the backlight was broken anyway with DT, how could this new patch
break it I wonder.

Thierry

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Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Laurent Pinchart]

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Hi Thierry,

On Wednesday 11 December 2013 16:15:46 Thierry Reding wrote:
> On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> > Hello,
> > 
> > Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight: Add power
> > supply support") added a mandatory power supply for the PWM backlight,
> > resulting in broken backlight on the Armadillo board. This patch set fixes
> > the issue by adding power supplies to board code and DT, and adds proper
> > handling of the panel enable signal through the PWM backlight enable
> > GPIO.
> > 
> > Patch 1/4 fixes a v3.13 regression.
> 
> Actually there should be no regression at all here. The regulator core
> handles this case by providing a dummy if the property hasn't been
> specified in DT.

The regression fixed by 1/4 only affects the legacy (non-DT) Armadillo 800 EVA 
platform. In that case the regulator core doesn't provide a dummy regulator.

> > Strictly speaking patch 3/4 is as well, but the backlight was broken
> > anyway with DT due to the enable GPIO not being handled at all, so
> > there's no need to push it to v3.13.
> 
> If the backlight was broken anyway with DT, how could this new patch break
> it I wonder.

It obviously doesn't change the end result :-) I thought it introduced a new 
bug, but given that the regulator core provides a dummy regulator in this 
case, patch 3/4 is indeed not a regression fix.

-- 
Regards,

Laurent Pinchart

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Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Simon Horman]

On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> Hello,
> 
> Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight: Add power
> supply support") added a mandatory power supply for the PWM backlight,
> resulting in broken backlight on the Armadillo board. This patch set fixes the
> issue by adding power supplies to board code and DT, and adds proper handling
> of the panel enable signal through the PWM backlight enable GPIO.
> 
> Patch 1/4 fixes a v3.13 regression. Strictly speaking patch 3/4 is as well,
> but the backlight was broken anyway with DT due to the enable GPIO not being
> handled at all, so there's no need to push it to v3.13.
> 
> Laurent Pinchart (4):
>   ARM: shmobile: armadillo: Add PWM backlight power supply
>   ARM: shmobile: armadillo: Set backlight enable GPIO
>   ARM: shmobile: armadillo: dts: Add PWM backlight power supply
>   ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO
> 
>  arch/arm/boot/dts/r8a7740-armadillo800eva-reference.dts | 11 +++++++++++
>  arch/arm/mach-shmobile/board-armadillo800eva.c          | 12 ++++++++----
>  2 files changed, 19 insertions(+), 4 deletions(-)

Hi Laurent,

I am wondering if you could let me know how you exercised this.
I am not having much luck using /dev/fb/0.

I have your patches applied on top of renesas-devel-v3.13-rc3-20131214v2

Using Legacy-C I see the following:
dmesg | grep fb
sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: Coherent DMA mask 0xffffffffffffffff is larger than dma_addr_t allows
sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: Driver did not use or check the return value from dma_set_coherent_mask()?
sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: unable to allocate buffer sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.0 failed with error -12
sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: Coherent DMA mask 0xffffffffffffffff is larger than dma_addr_t allows
sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: Driver did not use or check the return value from dma_set_coherent_mask()?
sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: unable to allocate buffer sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.1 failed with error -12

And no fb devices in /dev

I am using armadillo800eva_defconfig


Using DT-Reference I see nothing relating to fb in dmeg or /dev

I am using armadillo800eva_defconfig with:
* CONFIG_MACH_ARMADILLO800EVA disabled
* CONFIG_MACH_ARMADILLO800EVA_REFERENCE enabled
* CONFIG_BLK_DEV_INITRD and friends enabled

Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Laurent Pinchart]

Hi Simon,

On Monday 16 December 2013 11:22:04 Simon Horman wrote:
> On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> > Hello,
> > 
> > Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight: Add power
> > supply support") added a mandatory power supply for the PWM backlight,
> > resulting in broken backlight on the Armadillo board. This patch set fixes
> > the issue by adding power supplies to board code and DT, and adds proper
> > handling of the panel enable signal through the PWM backlight enable
> > GPIO.
> > 
> > Patch 1/4 fixes a v3.13 regression. Strictly speaking patch 3/4 is as
> > well, but the backlight was broken anyway with DT due to the enable GPIO
> > not being handled at all, so there's no need to push it to v3.13.
> > 
> > Laurent Pinchart (4):
> >   ARM: shmobile: armadillo: Add PWM backlight power supply
> >   ARM: shmobile: armadillo: Set backlight enable GPIO
> >   ARM: shmobile: armadillo: dts: Add PWM backlight power supply
> >   ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO
> >  
> >  arch/arm/boot/dts/r8a7740-armadillo800eva-reference.dts | 11 +++++++++++
> >  arch/arm/mach-shmobile/board-armadillo800eva.c          | 12 ++++++++----
> >  2 files changed, 19 insertions(+), 4 deletions(-)
> 
> Hi Laurent,
> 
> I am wondering if you could let me know how you exercised this.
> I am not having much luck using /dev/fb/0.
> 
> I have your patches applied on top of renesas-devel-v3.13-rc3-20131214v2
> 
> Using Legacy-C I see the following:
> dmesg | grep fb
> sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: Coherent DMA mask 0xffffffffffffffff
> is larger than dma_addr_t allows sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0:
> Driver did not use or check the return value from dma_set_coherent_mask()?
> sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: unable to allocate buffer
> sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.0 failed with error -12
> sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: Coherent DMA mask 0xffffffffffffffff
> is larger than dma_addr_t allows sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1:
> Driver did not use or check the return value from dma_set_coherent_mask()?
> sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: unable to allocate buffer
> sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.1 failed with error -12
> 
> And no fb devices in /dev
> 
> I am using armadillo800eva_defconfig

I've tried that and got the same error. My kernel config has 
CONFIG_SHMOBILE_IOMMU enabled which seems to hide the problem. I'll come up 
with a patch to get LCDC working without IOMMU.

> Using DT-Reference I see nothing relating to fb in dmeg or /dev
> 
> I am using armadillo800eva_defconfig with:
> * CONFIG_MACH_ARMADILLO800EVA disabled
> * CONFIG_MACH_ARMADILLO800EVA_REFERENCE enabled
> * CONFIG_BLK_DEV_INITRD and friends enabled

The DT-reference board doesn't enable LCDC.

-- 
Regards,

Laurent Pinchart

Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Simon Horman]

On Mon, Dec 16, 2013 at 04:43:39PM +0100, Laurent Pinchart wrote:
> Hi Simon,
> 
> On Monday 16 December 2013 11:22:04 Simon Horman wrote:
> > On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> > > Hello,
> > > 
> > > Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight: Add power
> > > supply support") added a mandatory power supply for the PWM backlight,
> > > resulting in broken backlight on the Armadillo board. This patch set fixes
> > > the issue by adding power supplies to board code and DT, and adds proper
> > > handling of the panel enable signal through the PWM backlight enable
> > > GPIO.
> > > 
> > > Patch 1/4 fixes a v3.13 regression. Strictly speaking patch 3/4 is as
> > > well, but the backlight was broken anyway with DT due to the enable GPIO
> > > not being handled at all, so there's no need to push it to v3.13.
> > > 
> > > Laurent Pinchart (4):
> > >   ARM: shmobile: armadillo: Add PWM backlight power supply
> > >   ARM: shmobile: armadillo: Set backlight enable GPIO
> > >   ARM: shmobile: armadillo: dts: Add PWM backlight power supply
> > >   ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO
> > >  
> > >  arch/arm/boot/dts/r8a7740-armadillo800eva-reference.dts | 11 +++++++++++
> > >  arch/arm/mach-shmobile/board-armadillo800eva.c          | 12 ++++++++----
> > >  2 files changed, 19 insertions(+), 4 deletions(-)
> > 
> > Hi Laurent,
> > 
> > I am wondering if you could let me know how you exercised this.
> > I am not having much luck using /dev/fb/0.
> > 
> > I have your patches applied on top of renesas-devel-v3.13-rc3-20131214v2
> > 
> > Using Legacy-C I see the following:
> > dmesg | grep fb
> > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: Coherent DMA mask 0xffffffffffffffff
> > is larger than dma_addr_t allows sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0:
> > Driver did not use or check the return value from dma_set_coherent_mask()?
> > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: unable to allocate buffer
> > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.0 failed with error -12
> > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: Coherent DMA mask 0xffffffffffffffff
> > is larger than dma_addr_t allows sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1:
> > Driver did not use or check the return value from dma_set_coherent_mask()?
> > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: unable to allocate buffer
> > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.1 failed with error -12
> > 
> > And no fb devices in /dev
> > 
> > I am using armadillo800eva_defconfig
> 
> I've tried that and got the same error. My kernel config has 
> CONFIG_SHMOBILE_IOMMU enabled which seems to hide the problem. I'll come up 
> with a patch to get LCDC working without IOMMU.

Thanks.

> > Using DT-Reference I see nothing relating to fb in dmeg or /dev
> > 
> > I am using armadillo800eva_defconfig with:
> > * CONFIG_MACH_ARMADILLO800EVA disabled
> > * CONFIG_MACH_ARMADILLO800EVA_REFERENCE enabled
> > * CONFIG_BLK_DEV_INITRD and friends enabled
> 
> The DT-reference board doesn't enable LCDC.

Understood.

Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Simon Horman]

On Tue, Dec 17, 2013 at 09:20:04AM +0900, Simon Horman wrote:
> On Mon, Dec 16, 2013 at 04:43:39PM +0100, Laurent Pinchart wrote:
> > Hi Simon,
> > 
> > On Monday 16 December 2013 11:22:04 Simon Horman wrote:
> > > On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> > > > Hello,
> > > > 
> > > > Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight: Add power
> > > > supply support") added a mandatory power supply for the PWM backlight,
> > > > resulting in broken backlight on the Armadillo board. This patch set fixes
> > > > the issue by adding power supplies to board code and DT, and adds proper
> > > > handling of the panel enable signal through the PWM backlight enable
> > > > GPIO.
> > > > 
> > > > Patch 1/4 fixes a v3.13 regression. Strictly speaking patch 3/4 is as
> > > > well, but the backlight was broken anyway with DT due to the enable GPIO
> > > > not being handled at all, so there's no need to push it to v3.13.
> > > > 
> > > > Laurent Pinchart (4):
> > > >   ARM: shmobile: armadillo: Add PWM backlight power supply
> > > >   ARM: shmobile: armadillo: Set backlight enable GPIO
> > > >   ARM: shmobile: armadillo: dts: Add PWM backlight power supply
> > > >   ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO
> > > >  
> > > >  arch/arm/boot/dts/r8a7740-armadillo800eva-reference.dts | 11 +++++++++++
> > > >  arch/arm/mach-shmobile/board-armadillo800eva.c          | 12 ++++++++----
> > > >  2 files changed, 19 insertions(+), 4 deletions(-)
> > > 
> > > Hi Laurent,
> > > 
> > > I am wondering if you could let me know how you exercised this.
> > > I am not having much luck using /dev/fb/0.
> > > 
> > > I have your patches applied on top of renesas-devel-v3.13-rc3-20131214v2
> > > 
> > > Using Legacy-C I see the following:
> > > dmesg | grep fb
> > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: Coherent DMA mask 0xffffffffffffffff
> > > is larger than dma_addr_t allows sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0:
> > > Driver did not use or check the return value from dma_set_coherent_mask()?
> > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: unable to allocate buffer
> > > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.0 failed with error -12
> > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: Coherent DMA mask 0xffffffffffffffff
> > > is larger than dma_addr_t allows sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1:
> > > Driver did not use or check the return value from dma_set_coherent_mask()?
> > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: unable to allocate buffer
> > > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.1 failed with error -12
> > > 
> > > And no fb devices in /dev
> > > 
> > > I am using armadillo800eva_defconfig
> > 
> > I've tried that and got the same error. My kernel config has 
> > CONFIG_SHMOBILE_IOMMU enabled which seems to hide the problem. I'll come up 
> > with a patch to get LCDC working without IOMMU.
> 
> Thanks.

I have applied "[PATCH 1/3] ARM: shmobile: armadillo: Fix coherent DMA
mask" and the problems I reported above seem to have been resolved, thanks.

Unfortunately my test of LCDC still seems to fail, so perhaps I need a
different test.

My test is as follows:

bmap /dev/fb0 test.bmp


Where bmap is:

git clone git://github.com/morimoto/bmap.git
cd bmap/
git checkout 6f64f8beee1be0c2f57752265a0568706d77794b
echo "CROSS = arm-linux-gnueabi-" > .config
make

And test.bmp is
http://horms.org/tmp/test.bmp

> 
> > > Using DT-Reference I see nothing relating to fb in dmeg or /dev
> > > 
> > > I am using armadillo800eva_defconfig with:
> > > * CONFIG_MACH_ARMADILLO800EVA disabled
> > > * CONFIG_MACH_ARMADILLO800EVA_REFERENCE enabled
> > > * CONFIG_BLK_DEV_INITRD and friends enabled
> > 
> > The DT-reference board doesn't enable LCDC.
> 
> Understood.
> --
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> 

Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Laurent Pinchart]

Hi Simon,

On Tuesday 17 December 2013 09:56:30 Simon Horman wrote:
> On Tue, Dec 17, 2013 at 09:20:04AM +0900, Simon Horman wrote:
> > On Mon, Dec 16, 2013 at 04:43:39PM +0100, Laurent Pinchart wrote:
> > > On Monday 16 December 2013 11:22:04 Simon Horman wrote:
> > > > On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> > > > > Hello,
> > > > > 
> > > > > Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight: Add
> > > > > power supply support") added a mandatory power supply for the PWM
> > > > > backlight, resulting in broken backlight on the Armadillo board.
> > > > > This patch set fixes the issue by adding power supplies to board
> > > > > code and DT, and adds proper handling of the panel enable signal
> > > > > through the PWM backlight enable GPIO.
> > > > > 
> > > > > Patch 1/4 fixes a v3.13 regression. Strictly speaking patch 3/4 is
> > > > > as well, but the backlight was broken anyway with DT due to the
> > > > > enable GPIO not being handled at all, so there's no need to push it
> > > > > to v3.13.
> > > > > 
> > > > > Laurent Pinchart (4):
> > > > >   ARM: shmobile: armadillo: Add PWM backlight power supply
> > > > >   ARM: shmobile: armadillo: Set backlight enable GPIO
> > > > >   ARM: shmobile: armadillo: dts: Add PWM backlight power supply
> > > > >   ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO
> > > > >  
> > > > >  arch/arm/boot/dts/r8a7740-armadillo800eva-reference.dts | 11 ++++++
> > > > >  arch/arm/mach-shmobile/board-armadillo800eva.c          | 12 ++++--
> > > > >  2 files changed, 19 insertions(+), 4 deletions(-)
> > > > 
> > > > Hi Laurent,
> > > > 
> > > > I am wondering if you could let me know how you exercised this.
> > > > I am not having much luck using /dev/fb/0.
> > > > 
> > > > I have your patches applied on top of
> > > > renesas-devel-v3.13-rc3-20131214v2
> > > > 
> > > > Using Legacy-C I see the following:
> > > > dmesg | grep fb
> > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: Coherent DMA mask
> > > > 0xffffffffffffffff is larger than dma_addr_t allows sh_mobile_lcdc_fb
> > > > sh_mobile_lcdc_fb.0: Driver did not use or check the return value from
> > > > dma_set_coherent_mask()?
> > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: unable to allocate buffer
> > > > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.0 failed with error -12
> > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: Coherent DMA mask
> > > > 0xffffffffffffffff is larger than dma_addr_t allows sh_mobile_lcdc_fb
> > > > sh_mobile_lcdc_fb.1: Driver did not use or check the return value from
> > > > dma_set_coherent_mask()?
> > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: unable to allocate buffer
> > > > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.1 failed with error -12
> > > > 
> > > > And no fb devices in /dev
> > > > 
> > > > I am using armadillo800eva_defconfig
> > > 
> > > I've tried that and got the same error. My kernel config has
> > > CONFIG_SHMOBILE_IOMMU enabled which seems to hide the problem. I'll come
> > > up with a patch to get LCDC working without IOMMU.
> > 
> > Thanks.
> 
> I have applied "[PATCH 1/3] ARM: shmobile: armadillo: Fix coherent DMA
> mask" and the problems I reported above seem to have been resolved, thanks.
> 
> Unfortunately my test of LCDC still seems to fail, so perhaps I need a
> different test.
> 
> My test is as follows:
> 
> bmap /dev/fb0 test.bmp
> 
> Where bmap is:
> 
> git clone git://github.com/morimoto/bmap.git
> cd bmap/
> git checkout 6f64f8beee1be0c2f57752265a0568706d77794b
> echo "CROSS = arm-linux-gnueabi-" > .config
> make
> 
> And test.bmp is
> http://horms.org/tmp/test.bmp

It looks like th LCDC FB driver doesn't work correctly when IOMMU support is 
enabled. Given that the IOMMU driver seems to be broken and untested anyway 
(see the two fixes I've just sent), my recommendation would be to turn IOMMU 
support off until this can get investigated.

> > > > Using DT-Reference I see nothing relating to fb in dmeg or /dev
> > > > 
> > > > I am using armadillo800eva_defconfig with:
> > > > * CONFIG_MACH_ARMADILLO800EVA disabled
> > > > * CONFIG_MACH_ARMADILLO800EVA_REFERENCE enabled
> > > > * CONFIG_BLK_DEV_INITRD and friends enabled
> > > 
> > > The DT-reference board doesn't enable LCDC.
> > 
> > Understood.

-- 
Regards,

Laurent Pinchart

Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Simon Horman]

On Tue, Dec 17, 2013 at 06:19:57PM +0100, Laurent Pinchart wrote:
> Hi Simon,
> 
> On Tuesday 17 December 2013 09:56:30 Simon Horman wrote:
> > On Tue, Dec 17, 2013 at 09:20:04AM +0900, Simon Horman wrote:
> > > On Mon, Dec 16, 2013 at 04:43:39PM +0100, Laurent Pinchart wrote:
> > > > On Monday 16 December 2013 11:22:04 Simon Horman wrote:
> > > > > On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> > > > > > Hello,
> > > > > > 
> > > > > > Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight: Add
> > > > > > power supply support") added a mandatory power supply for the PWM
> > > > > > backlight, resulting in broken backlight on the Armadillo board.
> > > > > > This patch set fixes the issue by adding power supplies to board
> > > > > > code and DT, and adds proper handling of the panel enable signal
> > > > > > through the PWM backlight enable GPIO.
> > > > > > 
> > > > > > Patch 1/4 fixes a v3.13 regression. Strictly speaking patch 3/4 is
> > > > > > as well, but the backlight was broken anyway with DT due to the
> > > > > > enable GPIO not being handled at all, so there's no need to push it
> > > > > > to v3.13.
> > > > > > 
> > > > > > Laurent Pinchart (4):
> > > > > >   ARM: shmobile: armadillo: Add PWM backlight power supply
> > > > > >   ARM: shmobile: armadillo: Set backlight enable GPIO
> > > > > >   ARM: shmobile: armadillo: dts: Add PWM backlight power supply
> > > > > >   ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO
> > > > > >  
> > > > > >  arch/arm/boot/dts/r8a7740-armadillo800eva-reference.dts | 11 ++++++
> > > > > >  arch/arm/mach-shmobile/board-armadillo800eva.c          | 12 ++++--
> > > > > >  2 files changed, 19 insertions(+), 4 deletions(-)
> > > > > 
> > > > > Hi Laurent,
> > > > > 
> > > > > I am wondering if you could let me know how you exercised this.
> > > > > I am not having much luck using /dev/fb/0.
> > > > > 
> > > > > I have your patches applied on top of
> > > > > renesas-devel-v3.13-rc3-20131214v2
> > > > > 
> > > > > Using Legacy-C I see the following:
> > > > > dmesg | grep fb
> > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: Coherent DMA mask
> > > > > 0xffffffffffffffff is larger than dma_addr_t allows sh_mobile_lcdc_fb
> > > > > sh_mobile_lcdc_fb.0: Driver did not use or check the return value from
> > > > > dma_set_coherent_mask()?
> > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: unable to allocate buffer
> > > > > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.0 failed with error -12
> > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: Coherent DMA mask
> > > > > 0xffffffffffffffff is larger than dma_addr_t allows sh_mobile_lcdc_fb
> > > > > sh_mobile_lcdc_fb.1: Driver did not use or check the return value from
> > > > > dma_set_coherent_mask()?
> > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: unable to allocate buffer
> > > > > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.1 failed with error -12
> > > > > 
> > > > > And no fb devices in /dev
> > > > > 
> > > > > I am using armadillo800eva_defconfig
> > > > 
> > > > I've tried that and got the same error. My kernel config has
> > > > CONFIG_SHMOBILE_IOMMU enabled which seems to hide the problem. I'll come
> > > > up with a patch to get LCDC working without IOMMU.
> > > 
> > > Thanks.
> > 
> > I have applied "[PATCH 1/3] ARM: shmobile: armadillo: Fix coherent DMA
> > mask" and the problems I reported above seem to have been resolved, thanks.
> > 
> > Unfortunately my test of LCDC still seems to fail, so perhaps I need a
> > different test.
> > 
> > My test is as follows:
> > 
> > bmap /dev/fb0 test.bmp
> > 
> > Where bmap is:
> > 
> > git clone git://github.com/morimoto/bmap.git
> > cd bmap/
> > git checkout 6f64f8beee1be0c2f57752265a0568706d77794b
> > echo "CROSS = arm-linux-gnueabi-" > .config
> > make
> > 
> > And test.bmp is
> > http://horms.org/tmp/test.bmp
> 
> It looks like th LCDC FB driver doesn't work correctly when IOMMU support is 
> enabled. Given that the IOMMU driver seems to be broken and untested anyway 
> (see the two fixes I've just sent), my recommendation would be to turn IOMMU 
> support off until this can get investigated.

Thanks, I think that seems sensible.

But I am a little confused.

I was under the impression that armadillo800eva_defconfig
did not enable IOMMU which is why I saw the problems relating
to the DMA mask that I reported above. And that is the configuration
I used again with the bmap test I reported immediately above.

I see this:
ARCH=arm make armadillo800eva_defconfig
grep IOMMU .config
CONFIG_IOMMU_HELPER=y
CONFIG_IOMMU_SUPPORT=y
CONFIG_OF_IOMMU=y
# CONFIG_SHMOBILE_IOMMU is not set

Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Laurent Pinchart]

Hi Simon,

(Dropping Thierry from the CC list)

On Wednesday 18 December 2013 10:34:17 Simon Horman wrote:
> On Tue, Dec 17, 2013 at 06:19:57PM +0100, Laurent Pinchart wrote:
> > On Tuesday 17 December 2013 09:56:30 Simon Horman wrote:
> > > On Tue, Dec 17, 2013 at 09:20:04AM +0900, Simon Horman wrote:
> > > > On Mon, Dec 16, 2013 at 04:43:39PM +0100, Laurent Pinchart wrote:
> > > > > On Monday 16 December 2013 11:22:04 Simon Horman wrote:
> > > > > > On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> > > > > > > Hello,
> > > > > > > 
> > > > > > > Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight:
> > > > > > > Add power supply support") added a mandatory power supply for
> > > > > > > the PWM backlight, resulting in broken backlight on the
> > > > > > > Armadillo board. This patch set fixes the issue by adding power
> > > > > > > supplies to board code and DT, and adds proper handling of the
> > > > > > > panel enable signal through the PWM backlight enable GPIO.
> > > > > > > 
> > > > > > > Patch 1/4 fixes a v3.13 regression. Strictly speaking patch 3/4
> > > > > > > is as well, but the backlight was broken anyway with DT due to
> > > > > > > the enable GPIO not being handled at all, so there's no need to
> > > > > > > push it to v3.13.
> > > > > > > 
> > > > > > > Laurent Pinchart (4):
> > > > > > >   ARM: shmobile: armadillo: Add PWM backlight power supply
> > > > > > >   ARM: shmobile: armadillo: Set backlight enable GPIO
> > > > > > >   ARM: shmobile: armadillo: dts: Add PWM backlight power supply
> > > > > > >   ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO
> > > > > > >  
> > > > > > >  arch/arm/boot/dts/r8a7740-armadillo800eva-reference.dts | 11
> > > > > > >  ++++++
> > > > > > >  arch/arm/mach-shmobile/board-armadillo800eva.c          | 12
> > > > > > >  ++++--
> > > > > > >  2 files changed, 19 insertions(+), 4 deletions(-)
> > > > > > 
> > > > > > Hi Laurent,
> > > > > > 
> > > > > > I am wondering if you could let me know how you exercised this.
> > > > > > I am not having much luck using /dev/fb/0.
> > > > > > 
> > > > > > I have your patches applied on top of
> > > > > > renesas-devel-v3.13-rc3-20131214v2
> > > > > > 
> > > > > > Using Legacy-C I see the following:
> > > > > > dmesg | grep fb
> > > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: Coherent DMA mask
> > > > > > 0xffffffffffffffff is larger than dma_addr_t allows
> > > > > > sh_mobile_lcdc_fb
> > > > > > sh_mobile_lcdc_fb.0: Driver did not use or check the return value
> > > > > > from
> > > > > > dma_set_coherent_mask()?
> > > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: unable to allocate buffer
> > > > > > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.0 failed with error
> > > > > > -12
> > > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: Coherent DMA mask
> > > > > > 0xffffffffffffffff is larger than dma_addr_t allows
> > > > > > sh_mobile_lcdc_fb
> > > > > > sh_mobile_lcdc_fb.1: Driver did not use or check the return value
> > > > > > from
> > > > > > dma_set_coherent_mask()?
> > > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: unable to allocate buffer
> > > > > > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.1 failed with error
> > > > > > -12
> > > > > > 
> > > > > > And no fb devices in /dev
> > > > > > 
> > > > > > I am using armadillo800eva_defconfig
> > > > > 
> > > > > I've tried that and got the same error. My kernel config has
> > > > > CONFIG_SHMOBILE_IOMMU enabled which seems to hide the problem. I'll
> > > > > come
> > > > > up with a patch to get LCDC working without IOMMU.
> > > > 
> > > > Thanks.
> > > 
> > > I have applied "[PATCH 1/3] ARM: shmobile: armadillo: Fix coherent DMA
> > > mask" and the problems I reported above seem to have been resolved,
> > > thanks.
> > > 
> > > Unfortunately my test of LCDC still seems to fail, so perhaps I need a
> > > different test.
> > > 
> > > My test is as follows:
> > > 
> > > bmap /dev/fb0 test.bmp
> > > 
> > > Where bmap is:
> > > 
> > > git clone git://github.com/morimoto/bmap.git
> > > cd bmap/
> > > git checkout 6f64f8beee1be0c2f57752265a0568706d77794b
> > > echo "CROSS = arm-linux-gnueabi-" > .config
> > > make
> > > 
> > > And test.bmp is
> > > http://horms.org/tmp/test.bmp
> > 
> > It looks like th LCDC FB driver doesn't work correctly when IOMMU support
> > is enabled. Given that the IOMMU driver seems to be broken and untested
> > anyway (see the two fixes I've just sent), my recommendation would be to
> > turn IOMMU support off until this can get investigated.
> 
> Thanks, I think that seems sensible.
> 
> But I am a little confused.
> 
> I was under the impression that armadillo800eva_defconfig
> did not enable IOMMU which is why I saw the problems relating
> to the DMA mask that I reported above. And that is the configuration
> I used again with the bmap test I reported immediately above.
> 
> I see this:
> ARCH=arm make armadillo800eva_defconfig
> grep IOMMU .config
> CONFIG_IOMMU_HELPER=y
> CONFIG_IOMMU_SUPPORT=y
> CONFIG_OF_IOMMU=y
> # CONFIG_SHMOBILE_IOMMU is not set

Right, so IOMMU was only an issue for me, not for you. I believe you're just 
missing the RENESAS_TPU and BACKLIGHT_PWM options in your .config. I've sent a 
patch that adds both to armadillo800eva_defconfig, could you please test it ?

-- 
Regards,

Laurent Pinchart

Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Simon Horman]

On Wed, Dec 18, 2013 at 03:06:02PM +0100, Laurent Pinchart wrote:
> Hi Simon,
> 
> (Dropping Thierry from the CC list)
> 
> On Wednesday 18 December 2013 10:34:17 Simon Horman wrote:
> > On Tue, Dec 17, 2013 at 06:19:57PM +0100, Laurent Pinchart wrote:
> > > On Tuesday 17 December 2013 09:56:30 Simon Horman wrote:
> > > > On Tue, Dec 17, 2013 at 09:20:04AM +0900, Simon Horman wrote:
> > > > > On Mon, Dec 16, 2013 at 04:43:39PM +0100, Laurent Pinchart wrote:
> > > > > > On Monday 16 December 2013 11:22:04 Simon Horman wrote:
> > > > > > > On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> > > > > > > > Hello,
> > > > > > > > 
> > > > > > > > Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight:
> > > > > > > > Add power supply support") added a mandatory power supply for
> > > > > > > > the PWM backlight, resulting in broken backlight on the
> > > > > > > > Armadillo board. This patch set fixes the issue by adding power
> > > > > > > > supplies to board code and DT, and adds proper handling of the
> > > > > > > > panel enable signal through the PWM backlight enable GPIO.
> > > > > > > > 
> > > > > > > > Patch 1/4 fixes a v3.13 regression. Strictly speaking patch 3/4
> > > > > > > > is as well, but the backlight was broken anyway with DT due to
> > > > > > > > the enable GPIO not being handled at all, so there's no need to
> > > > > > > > push it to v3.13.
> > > > > > > > 
> > > > > > > > Laurent Pinchart (4):
> > > > > > > >   ARM: shmobile: armadillo: Add PWM backlight power supply
> > > > > > > >   ARM: shmobile: armadillo: Set backlight enable GPIO
> > > > > > > >   ARM: shmobile: armadillo: dts: Add PWM backlight power supply
> > > > > > > >   ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO
> > > > > > > >  
> > > > > > > >  arch/arm/boot/dts/r8a7740-armadillo800eva-reference.dts | 11
> > > > > > > >  ++++++
> > > > > > > >  arch/arm/mach-shmobile/board-armadillo800eva.c          | 12
> > > > > > > >  ++++--
> > > > > > > >  2 files changed, 19 insertions(+), 4 deletions(-)
> > > > > > > 
> > > > > > > Hi Laurent,
> > > > > > > 
> > > > > > > I am wondering if you could let me know how you exercised this.
> > > > > > > I am not having much luck using /dev/fb/0.
> > > > > > > 
> > > > > > > I have your patches applied on top of
> > > > > > > renesas-devel-v3.13-rc3-20131214v2
> > > > > > > 
> > > > > > > Using Legacy-C I see the following:
> > > > > > > dmesg | grep fb
> > > > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: Coherent DMA mask
> > > > > > > 0xffffffffffffffff is larger than dma_addr_t allows
> > > > > > > sh_mobile_lcdc_fb
> > > > > > > sh_mobile_lcdc_fb.0: Driver did not use or check the return value
> > > > > > > from
> > > > > > > dma_set_coherent_mask()?
> > > > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.0: unable to allocate buffer
> > > > > > > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.0 failed with error
> > > > > > > -12
> > > > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: Coherent DMA mask
> > > > > > > 0xffffffffffffffff is larger than dma_addr_t allows
> > > > > > > sh_mobile_lcdc_fb
> > > > > > > sh_mobile_lcdc_fb.1: Driver did not use or check the return value
> > > > > > > from
> > > > > > > dma_set_coherent_mask()?
> > > > > > > sh_mobile_lcdc_fb sh_mobile_lcdc_fb.1: unable to allocate buffer
> > > > > > > sh_mobile_lcdc_fb: probe of sh_mobile_lcdc_fb.1 failed with error
> > > > > > > -12
> > > > > > > 
> > > > > > > And no fb devices in /dev
> > > > > > > 
> > > > > > > I am using armadillo800eva_defconfig
> > > > > > 
> > > > > > I've tried that and got the same error. My kernel config has
> > > > > > CONFIG_SHMOBILE_IOMMU enabled which seems to hide the problem. I'll
> > > > > > come
> > > > > > up with a patch to get LCDC working without IOMMU.
> > > > > 
> > > > > Thanks.
> > > > 
> > > > I have applied "[PATCH 1/3] ARM: shmobile: armadillo: Fix coherent DMA
> > > > mask" and the problems I reported above seem to have been resolved,
> > > > thanks.
> > > > 
> > > > Unfortunately my test of LCDC still seems to fail, so perhaps I need a
> > > > different test.
> > > > 
> > > > My test is as follows:
> > > > 
> > > > bmap /dev/fb0 test.bmp
> > > > 
> > > > Where bmap is:
> > > > 
> > > > git clone git://github.com/morimoto/bmap.git
> > > > cd bmap/
> > > > git checkout 6f64f8beee1be0c2f57752265a0568706d77794b
> > > > echo "CROSS = arm-linux-gnueabi-" > .config
> > > > make
> > > > 
> > > > And test.bmp is
> > > > http://horms.org/tmp/test.bmp
> > > 
> > > It looks like th LCDC FB driver doesn't work correctly when IOMMU support
> > > is enabled. Given that the IOMMU driver seems to be broken and untested
> > > anyway (see the two fixes I've just sent), my recommendation would be to
> > > turn IOMMU support off until this can get investigated.
> > 
> > Thanks, I think that seems sensible.
> > 
> > But I am a little confused.
> > 
> > I was under the impression that armadillo800eva_defconfig
> > did not enable IOMMU which is why I saw the problems relating
> > to the DMA mask that I reported above. And that is the configuration
> > I used again with the bmap test I reported immediately above.
> > 
> > I see this:
> > ARCH=arm make armadillo800eva_defconfig
> > grep IOMMU .config
> > CONFIG_IOMMU_HELPER=y
> > CONFIG_IOMMU_SUPPORT=y
> > CONFIG_OF_IOMMU=y
> > # CONFIG_SHMOBILE_IOMMU is not set
> 
> Right, so IOMMU was only an issue for me, not for you. I believe you're
> just missing the RENESAS_TPU and BACKLIGHT_PWM options in your .config.
> I've sent a patch that adds both to armadillo800eva_defconfig, could you
> please test it ?

Thanks, that did the trick.

I will queue up the following patches that relate to this problem.

ARM: shmobile: armadillo800eva: Enable backlight control in defconfig
ARM: shmobile: armadillo: Fix coherent DMA mask
ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO
ARM: shmobile: armadillo: dts: Add PWM backlight power supply
ARM: shmobile: armadillo: Set backlight enable GPIO
ARM: shmobile: armadillo: Add PWM backlight power supply

Re: [PATCH 0/4] Fix backlight on Armadillo 800 EVA

[Simon Horman]

Hi Laurent,

On Wed, Dec 11, 2013 at 03:48:14AM +0100, Laurent Pinchart wrote:
> Hello,
> 
> Commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 ("pwm-backlight: Add power
> supply support") added a mandatory power supply for the PWM backlight,
> resulting in broken backlight on the Armadillo board. This patch set fixes the
> issue by adding power supplies to board code and DT, and adds proper handling
> of the panel enable signal through the PWM backlight enable GPIO.
> 
> Patch 1/4 fixes a v3.13 regression. Strictly speaking patch 3/4 is as well,
> but the backlight was broken anyway with DT due to the enable GPIO not being
> handled at all, so there's no need to push it to v3.13.
> 
> Laurent Pinchart (4):
>   ARM: shmobile: armadillo: Add PWM backlight power supply

I have queued the first patch up as a fix for v3.13.

>   ARM: shmobile: armadillo: Set backlight enable GPIO
>   ARM: shmobile: armadillo: dts: Add PWM backlight power supply
>   ARM: shmobile: armadillo: dts: Add PWM backlight enable GPIO

I have queued up the rest for v3.14.

>  arch/arm/boot/dts/r8a7740-armadillo800eva-reference.dts | 11 +++++++++++
>  arch/arm/mach-shmobile/board-armadillo800eva.c          | 12 ++++++++----
>  2 files changed, 19 insertions(+), 4 deletions(-)