LCDC of 7203

LCDC of 7203

[Fabio Giovagnini]

Hi all,
I have a little problem with LCDC of sh2a 7203.
I seem not to see the driver into the last kernel.
Where could I find a good reference?

Thanks
-- 
Fabio Giovagnini

Aurion s.r.l.
P.I e C.F.
00885711200
Tel. +39.051.594.78.24
Cell. +39.335.83.50.919

Re: LCDC of 7203

[Magnus Damm]

Hi Fabio,

On Mon, May 24, 2010 at 1:12 PM, Fabio Giovagnini
<fabio.giovagnini@aurion-tech.com> wrote:
> Hi all,
> I have a little problem with LCDC of sh2a 7203.
> I seem not to see the driver into the last kernel.
> Where could I find a good reference?

I don't think there is any upstream 7203 LCDC driver. It's a shame, I
really wish people would submit their code upstream.

Thanks for your help!

/ magnus

Re: LCDC of 7203

[Fabio Giovagnini]

Hi Magnus
I'll do as soon I'll have something more stable

Cheers


In data mercoledì 26 maggio 2010 08:20:05, Magnus Damm ha scritto:
: > Hi Fabio,
> 
> On Mon, May 24, 2010 at 1:12 PM, Fabio Giovagnini
> 
> <fabio.giovagnini@aurion-tech.com> wrote:
> > Hi all,
> > I have a little problem with LCDC of sh2a 7203.
> > I seem not to see the driver into the last kernel.
> > Where could I find a good reference?
> 
> I don't think there is any upstream 7203 LCDC driver. It's a shame, I
> really wish people would submit their code upstream.
> 
> Thanks for your help!
> 
> / magnus
> --
> To unsubscribe from this list: send the line "unsubscribe linux-sh" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

-- 
Fabio Giovagnini

Aurion s.r.l.
P.I e C.F.
00885711200
Tel. +39.051.594.78.24
Cell. +39.335.83.50.919

Re: LCDC of 7203

[Paul Mundt]

On Wed, May 26, 2010 at 02:20:05AM -0400, Magnus Damm wrote:
> On Mon, May 24, 2010 at 1:12 PM, Fabio Giovagnini
> <fabio.giovagnini@aurion-tech.com> wrote:
> > Hi all,
> > I have a little problem with LCDC of sh2a 7203.
> > I seem not to see the driver into the last kernel.
> > Where could I find a good reference?
> 
> I don't think there is any upstream 7203 LCDC driver. It's a shame, I
> really wish people would submit their code upstream.
> 
I don't remember the details specifically, I thought the issue was panel
control via MSIOF and so on, which isn't too different from G3EVM?

The existing "drivers" are much like the early G3EVM LCD support, so
while references are readily available, there's little that is directly
usable without some serious work on the infrastructure side. Perhaps we
can reuse parts of the SH-Mobile LCD support?

Re: LCDC of 7203

[Magnus Damm]

On Wed, May 26, 2010 at 3:14 AM, Paul Mundt <lethal@linux-sh.org> wrote:
> On Wed, May 26, 2010 at 02:20:05AM -0400, Magnus Damm wrote:
>> On Mon, May 24, 2010 at 1:12 PM, Fabio Giovagnini
>> <fabio.giovagnini@aurion-tech.com> wrote:
>> > Hi all,
>> > I have a little problem with LCDC of sh2a 7203.
>> > I seem not to see the driver into the last kernel.
>> > Where could I find a good reference?
>>
>> I don't think there is any upstream 7203 LCDC driver. It's a shame, I
>> really wish people would submit their code upstream.
>>
> I don't remember the details specifically, I thought the issue was panel
> control via MSIOF and so on, which isn't too different from G3EVM?

Some LCD panels come with a dedicated control channel over SPI/I2C,
and some have their control channel muxed with pixel data like SYS or
MIPI.

I think rsk7203 dealt with the LCD panel setup over SPI, and most
likely that SPI channel was hooked up to an SIOF or SIO. The MSIOF
only exists on newer SH-Mobiles, so we would need a new SPI driver for
SIOF or whatever is there to begin with. Perhaps the easiest is just
to use an GPIO bitbang driver, but that requires pinmux support which
probably is in place on some sh2a processor at least.

> The existing "drivers" are much like the early G3EVM LCD support, so
> while references are readily available, there's little that is directly
> usable without some serious work on the infrastructure side. Perhaps we
> can reuse parts of the SH-Mobile LCD support?

From my POV, the biggest showstopper is that the SPI code is lacking
support for using the bus without the driver model. I2C allows this,
good or bad. It's sort of a hack, but there is nothing better
available either. With I2C we can have some board specific support
code for the LCD panel like the hack on Migo-R. This is not possible
with SPI AFAIK.

Perhaps the proper way is to add the LCD panel to the driver model and
then write a normal SPI driver for the LCD, but that brings up init
order issues.

The G3EVM code is setting up the LCD panel using the MSIOF in SPI
mode. The original code just accessed the MSIOF directly, but we
should be able to use the SPI driver instead. The MSIOF hardware block
on SH-Mobile ARM is unfortunately not working well with the MSIOF
driver, so it's a bit of a mess. SPI bitbang could be useful in this
case too though if the SPI-without-driver-model could be sorted out.

I think the MIPI work by Guennadi is one step in the right direction.

/ magnus

Re: LCDC of 7203

[Fabio Giovagnini]

There are some low cost LCD having a parallel interface with the synch signals 
and 16 / 18 bit of data.
The sh2a LCDC can manage such LCD panels

Am I right or not?


In data mercoledì 26 maggio 2010 09:34:36, Magnus Damm ha scritto:
: > On Wed, May 26, 2010 at 3:14 AM, Paul Mundt <lethal@linux-sh.org> wrote:
> > On Wed, May 26, 2010 at 02:20:05AM -0400, Magnus Damm wrote:
> >> On Mon, May 24, 2010 at 1:12 PM, Fabio Giovagnini
> >>
> >> <fabio.giovagnini@aurion-tech.com> wrote:
> >> > Hi all,
> >> > I have a little problem with LCDC of sh2a 7203.
> >> > I seem not to see the driver into the last kernel.
> >> > Where could I find a good reference?
> >>
> >> I don't think there is any upstream 7203 LCDC driver. It's a shame, I
> >> really wish people would submit their code upstream.
> >
> > I don't remember the details specifically, I thought the issue was panel
> > control via MSIOF and so on, which isn't too different from G3EVM?
> 
> Some LCD panels come with a dedicated control channel over SPI/I2C,
> and some have their control channel muxed with pixel data like SYS or
> MIPI.
> 
> I think rsk7203 dealt with the LCD panel setup over SPI, and most
> likely that SPI channel was hooked up to an SIOF or SIO. The MSIOF
> only exists on newer SH-Mobiles, so we would need a new SPI driver for
> SIOF or whatever is there to begin with. Perhaps the easiest is just
> to use an GPIO bitbang driver, but that requires pinmux support which
> probably is in place on some sh2a processor at least.
> 
> > The existing "drivers" are much like the early G3EVM LCD support, so
> > while references are readily available, there's little that is directly
> > usable without some serious work on the infrastructure side. Perhaps we
> > can reuse parts of the SH-Mobile LCD support?
> >
> >From my POV, the biggest showstopper is that the SPI code is lacking
> 
> support for using the bus without the driver model. I2C allows this,
> good or bad. It's sort of a hack, but there is nothing better
> available either. With I2C we can have some board specific support
> code for the LCD panel like the hack on Migo-R. This is not possible
> with SPI AFAIK.
> 
> Perhaps the proper way is to add the LCD panel to the driver model and
> then write a normal SPI driver for the LCD, but that brings up init
> order issues.
> 
> The G3EVM code is setting up the LCD panel using the MSIOF in SPI
> mode. The original code just accessed the MSIOF directly, but we
> should be able to use the SPI driver instead. The MSIOF hardware block
> on SH-Mobile ARM is unfortunately not working well with the MSIOF
> driver, so it's a bit of a mess. SPI bitbang could be useful in this
> case too though if the SPI-without-driver-model could be sorted out.
> 
> I think the MIPI work by Guennadi is one step in the right direction.
> 
> / magnus
> --
> To unsubscribe from this list: send the line "unsubscribe linux-sh" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

-- 
Fabio Giovagnini

Aurion s.r.l.
P.I e C.F.
00885711200
Tel. +39.051.594.78.24
Cell. +39.335.83.50.919

Re: LCDC of 7203

[Magnus Damm]

On Wed, May 26, 2010 at 3:54 AM, Fabio Giovagnini
<fabio.giovagnini@aurion-tech.com> wrote:
> There are some low cost LCD having a parallel interface with the synch signals
> and 16 / 18 bit of data.
> The sh2a LCDC can manage such LCD panels
>
> Am I right or not?

I don't know, you will have to check the data sheet.

It sounds like you are describing SYS-16/18, but it may also be RGB
with 6 bits for each color. Some LCDC hardware blocks like the
SH-Mobile support both RGB and SYS, but others only support one of the
interface types.

Cheers,

/ magnus