MMCIF support on sh7757lcr

MMCIF support on sh7757lcr

[Guennadi Liakhovetski]

Hello Shimoda-san

While reviewing MMCIF platform bindings, I came across your commit

commit 65f63eab38626a79f8a54d13686680a1ea898f72
Author: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Date:   Fri Feb 25 07:40:27 2011 +0000

    sh: add platform_device of tmio_mmc and sh_mmcif to sh7757lcr

There you only specify MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA 
capabilities for MMCIF. The MMCIF controller does not have any native 
support for card hotplug detection, therefore it must either be polled, or 
the card has to be marked non-removable. For polling it is also desired to 
provide a .get_cd() method. Neither of these is done for sh7757lcr. Is the 
MMC card on it removable? If so, is there any way to detect card presence 
in the slot?

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/

Re: MMCIF support on sh7757lcr

[Shimoda, Yoshihiro]

Hello Guennadi-san,

Thank you for your review.

2012/01/11 0:55, Guennadi Liakhovetski wrote:
> Hello Shimoda-san
> 
> While reviewing MMCIF platform bindings, I came across your commit
> 
> commit 65f63eab38626a79f8a54d13686680a1ea898f72
> Author: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Date:   Fri Feb 25 07:40:27 2011 +0000
> 
>     sh: add platform_device of tmio_mmc and sh_mmcif to sh7757lcr
> 
> There you only specify MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA 
> capabilities for MMCIF. The MMCIF controller does not have any native 
> support for card hotplug detection, therefore it must either be polled, or 
> the card has to be marked non-removable. For polling it is also desired to 
> provide a .get_cd() method. Neither of these is done for sh7757lcr. Is the 
> MMC card on it removable? If so, is there any way to detect card presence 
> in the slot?

This board doesn't have the MMC card slot. A MMC chip is on the board,
so we cannot remove the chip.
In the linux-3.2-rc7, the sh7757lcr can detect the MMC chip and
I can see the "mmcblk" device.

Best regards,
Yoshihiro Shimoda

> Thanks
> Guennadi
> ---
> Guennadi Liakhovetski, Ph.D.
> Freelance Open-Source Software Developer
> http://www.open-technology.de/
> 


-- 
Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
EC No.

Re: MMCIF support on sh7757lcr

[Guennadi Liakhovetski]

On Wed, 11 Jan 2012, Shimoda, Yoshihiro wrote:

> Hello Guennadi-san,
> 
> Thank you for your review.
> 
> 2012/01/11 0:55, Guennadi Liakhovetski wrote:
> > Hello Shimoda-san
> > 
> > While reviewing MMCIF platform bindings, I came across your commit
> > 
> > commit 65f63eab38626a79f8a54d13686680a1ea898f72
> > Author: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> > Date:   Fri Feb 25 07:40:27 2011 +0000
> > 
> >     sh: add platform_device of tmio_mmc and sh_mmcif to sh7757lcr
> > 
> > There you only specify MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA 
> > capabilities for MMCIF. The MMCIF controller does not have any native 
> > support for card hotplug detection, therefore it must either be polled, or 
> > the card has to be marked non-removable. For polling it is also desired to 
> > provide a .get_cd() method. Neither of these is done for sh7757lcr. Is the 
> > MMC card on it removable? If so, is there any way to detect card presence 
> > in the slot?
> 
> This board doesn't have the MMC card slot. A MMC chip is on the board,
> so we cannot remove the chip.
> In the linux-3.2-rc7, the sh7757lcr can detect the MMC chip and
> I can see the "mmcblk" device.

Right, it is detected upon driver initialisation, but id it were a normal 
slot, card ejects and inserts wouldn't be recognised. In this case we have 
to specify MMC_CAP_NONREMOVABLE among controller sapabilities:

static struct sh_mmcif_plat_data sh_mmcif_plat = {
	...
	.caps		= MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA |
				MMC_CAP_NONREMOVABLE,

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/

Re: MMCIF support on sh7757lcr

[Shimoda, Yoshihiro]

Hello Guennadi-san,

2012/01/11 17:24, Guennadi Liakhovetski wrote:
> Right, it is detected upon driver initialisation, but id it were a normal 
> slot, card ejects and inserts wouldn't be recognised. In this case we have 
> to specify MMC_CAP_NONREMOVABLE among controller sapabilities:
> 
> static struct sh_mmcif_plat_data sh_mmcif_plat = {
> 	...
> 	.caps		= MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA |
> 				MMC_CAP_NONREMOVABLE,

Thank you very much for your point.
I will write a patch for this.

Best regards,
Yoshihiro Shimoda

> Thanks
> Guennadi
> ---
> Guennadi Liakhovetski, Ph.D.
> Freelance Open-Source Software Developer
> http://www.open-technology.de/
>