[PATCH] MMC: OMAP R6 response support

[PATCH] MMC: OMAP R6 response support

[Carlos Aguiar]

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Hi folks,

Regarding the commit below

http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=6f949909e8f9e5d7e5584dc48d9a5e060c52aed1
,

the definition of response type R6 is the same as R1 and case
MMC_RSP_R6 was removed on omap.c, causing a error when inserting a SD
card on OMAP platforms.

This error occur due following the MMC and SD specs, on CMD3, response
type is R6 to SD cards and R1 to MMC cards.

So, I'm proposing a patch that try to solve this problem. I've tested
it with SD and MMC cards and looks fine.

Please, comments and suggestions are welcome.

BR,

Carlos.

-- 
Carlos Eduardo
Nokia Institute of Technology - INdT
Open Source Mobile Research Center - OSMRC
E-mail: carlos.aguiar@indt.org.br


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On CMD3, response type is R6 to SD cards and R1 to MMC cards.

Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>

Index: linux-omap/drivers/mmc/omap.c
===================================================================
--- linux-omap.orig/drivers/mmc/omap.c	2007-01-24 16:02:58.000000000 -0400
+++ linux-omap/drivers/mmc/omap.c	2007-01-25 09:31:40.000000000 -0400
@@ -209,8 +209,13 @@ mmc_omap_start_command(struct mmc_omap_h
 		break;
 	case MMC_RSP_R1:
 	case MMC_RSP_R1B:
-		/* resp 1, resp 1b */
-		resptype = 1;
+		if ((host->mmc->mode == MMC_MODE_SD) &&
+			(host->cmd->opcode == SD_SEND_RELATIVE_ADDR))
+			/* resp 6 */
+			resptype = 6;
+		else
+			/* resp 1, 1b, 7 */
+			resptype = 1;
 		break;
 	case MMC_RSP_R2:
 		resptype = 2;

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Re: [PATCH] MMC: OMAP R6 response support

[Pierre Ossman]

Carlos Aguiar wrote:
> Hi folks,
>
> Regarding the commit below
>
> http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=6f949909e8f9e5d7e5584dc48d9a5e060c52aed1
> ,
>
> the definition of response type R6 is the same as R1 and case
>   

That is intentional. All specs I have state that they have the same format.

> MMC_RSP_R6 was removed on omap.c, causing a error when inserting a SD
> card on OMAP platforms.
>   

Do you have a dump I could see?

> This error occur due following the MMC and SD specs, on CMD3, response
> type is R6 to SD cards and R1 to MMC cards.
>
> So, I'm proposing a patch that try to solve this problem. I've tested
> it with SD and MMC cards and looks fine.
>
>   

NAK. Opcodes should never be present in host drivers. It completely
kills forward compatibility. This should be fixed by figuring out what
the OMAP hardware does differently and do a general solution from that.

Rgds

-- 
     -- Pierre Ossman

  Linux kernel, MMC maintainer        http://www.kernel.org
  PulseAudio, core developer          http://pulseaudio.org
  rdesktop, core developer          http://www.rdesktop.org