[Acked] Re: [PATCH] mmc: Added quirks for Ricoh 1180:e823 lower base clock frequency

Leann Ogasawara leann.ogasawara at canonical.com
Mon Jul 25 16:45:32 UTC 2011


On Mon, 2011-07-25 at 11:38 -0500, Manoj Iyer wrote:
> Ricoh 1180:e823 does not recognize certain types of SD/MMC cards,
> as reported at http://launchpad.net/bugs/773524.  Lowering the SD
> base clock frequency from 200Mhz to 50Mhz fixes this issue. This
> solution was suggest by Koji Matsumuro, Ricoh Company, Ltd.
> 
> This change has no negative performance effect on standard SD
> cards, though it's quite possible that there will be one on
> UHS-1 cards.
> 
> Signed-off-by: Manoj Iyer <manoj.iyer at canonical.com>
> Tested-by: Daniel Manrique <daniel.manrique at canonical.com>
> Cc: Koji Matsumuro <matsumur at nts.ricoh.co.jp>
> Cc: <stable at kernel.org>
> Acked-by: Jesse Barnes <jbarnes at virtuousgeek.org>
> Signed-off-by: Chris Ball <cjb at laptop.org>
> (cherry picked from commit 15bed0f2fa8e1d7db201692532c210a7823d2d21)
> 
> Signed-off-by: Manoj Iyer <manoj.iyer at canonical.com>

Whomever commits this to Natty should add the BugLink.  Otherwise, this
is a low risk of regression and has positive test results.

Acked-by: Leann Ogasawara <leann.ogasawara at canonical.com>

> ---
>  drivers/pci/quirks.c |   23 +++++++++++++++++++++++
>  1 files changed, 23 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index a1e4f61..b1c312e 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -2755,6 +2755,29 @@ static void ricoh_mmc_fixup_r5c832(struct pci_dev *dev)
>  
>  	dev_notice(&dev->dev, "proprietary Ricoh MMC controller disabled (via firewire function)\n");
>  	dev_notice(&dev->dev, "MMC cards are now supported by standard SDHCI controller\n");
> +
> +	/*
> +	 * RICOH 0xe823 SD/MMC card reader fails to recognize
> +	 * certain types of SD/MMC cards. Lowering the SD base
> +	 * clock frequency from 200Mhz to 50Mhz fixes this issue.
> +	 *
> +	 * 0x150 - SD2.0 mode enable for changing base clock
> +	 *	   frequency to 50Mhz
> +	 * 0xe1  - Base clock frequency
> +	 * 0x32  - 50Mhz new clock frequency
> +	 * 0xf9  - Key register for 0x150
> +	 * 0xfc  - key register for 0xe1
> +	 */
> +	if (dev->device == PCI_DEVICE_ID_RICOH_R5CE823) {
> +		pci_write_config_byte(dev, 0xf9, 0xfc);
> +		pci_write_config_byte(dev, 0x150, 0x10);
> +		pci_write_config_byte(dev, 0xf9, 0x00);
> +		pci_write_config_byte(dev, 0xfc, 0x01);
> +		pci_write_config_byte(dev, 0xe1, 0x32);
> +		pci_write_config_byte(dev, 0xfc, 0x00);
> +
> +		dev_notice(&dev->dev, "MMC controller base frequency changed to 50Mhz.\n");
> +	}
>  }
>  DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_RICOH, PCI_DEVICE_ID_RICOH_R5C832, ricoh_mmc_fixup_r5c832);
>  DECLARE_PCI_FIXUP_RESUME_EARLY(PCI_VENDOR_ID_RICOH, PCI_DEVICE_ID_RICOH_R5C832, ricoh_mmc_fixup_r5c832);
> -- 
> 1.7.4.1
> 
> 





More information about the kernel-team mailing list