mvsdio not working on OpenRD

[Rick Thomas]

On Jan 10, 2016, at 7:38 AM, Andrew Lunn <andrew at lunn.ch> wrote:

> On Sat, Jan 09, 2016 at 08:26:19PM -0800, Martin Michlmayr wrote:
>> Rick Thomas reported that MMC no longer works on his OpenRD Base.
>> 
>> With Debian's 3.16 kernel (using mach ID):
>> 
>> mvsdio mvsdio: no pins associated
>> mmc0: host does not support reading read-only switch.  assuming write-enable.
>> mmc0: new high speed SDHC card at address 0007
>> mmcblk0: mmc0:0007 SD4GB 3.70 GiB·
>> mmcblk0: p1
>> 
>> With Debian's 4.3 and 4.4-rc8 kernels (using Device Tree):
>> 
>> kirkwood-pinctrl f1010000.pin-controller: pin PIN13 already requested by f1012100.serial; cannot claim for f1090000.mvsdio
>> kirkwood-pinctrl f1010000.pin-controller: pin-13 (f1090000.mvsdio) status -22
>> kirkwood-pinctrl f1010000.pin-controller: could not request pin 13 (PIN13) from group mpp13  on device f1010000.pin-controller
>> mvsdio f1090000.mvsdio: Error applying setting, reverse things back
>> mvsdio f1090000.mvsdio: Got CD GPIO
>> [and no mmc0 or mmcblk0]
>> 
>> -- 
>> Martin Michlmayr
>> http://www.cyrius.com/
> 
> Hi Rick, Martin
> 
> If i remember correctly, the OpenRD has some odd muxing going on with
> MMC and the second serial port. This fits the error message:
> 
>                        pmx_uart1: pmx-uart1 {
>                                marvell,pins = "mpp13", "mpp14";
>                                marvell,function = "uart1";
>                        };
> 
> and
> 
>                        pmx_sdio: pmx-sdio {
>                                marvell,pins = "mpp12", "mpp13", "mpp14",
>                                               "mpp15", "mpp16", "mpp17";
>                                marvell,function = "sdio";
> 			};
> 
> Either you can have MMC, or you can have the RS-232/RS485 on a DB9 or
> you can have MMC. You cannot have both.
> 
> It seems like older Debian kernels has defaulted to MMC, so we should
> probably disable the serial port.
> 
> Please can you try the following patch. If this works, i can add it to
> mainline. The issue we might run into is that somebody else wants
> serial not MMC....
> 
>       Andrew
> 
> diff --git a/arch/arm/boot/dts/kirkwood-openrd-base.dts b/arch/arm/boot/dts/kirkwood-openrd-base.dts
> index 8af58999606d..883bd416ba0b 100644
> --- a/arch/arm/boot/dts/kirkwood-openrd-base.dts
> +++ b/arch/arm/boot/dts/kirkwood-openrd-base.dts
> @@ -18,11 +18,6 @@
> / {
>        model = "OpenRD Base";
>        compatible = "marvell,openrd-base", "marvell,openrd", "marvell,kirkwood-88f6281", "marvell,kirkwood";
> -
> -       ocp at f1000000 {
> -               serial at 12100 {
> -                       status = "okay";
> -               };
>        };
> };

OK, I understand the issue, and what the patch would mean.  Given that Debian releases up thru Jessie have chosen to support MMC rather than RS-232/RS485, I don’t think there will be many Debian users who would complain.

Unfortuntaely, I’m not set up to build kernels here.  If someone can apply this patch and send me a link to the resulting binary or .deb or .dts, or … I’ll be happy to try it out on my test machine.

Thanks!
Rick