[PATCH] fix PXA27x MMC workaround for bad CRC with 136 bit response

From: Nicolas Pitre
Date: Sat May 12 2007 - 23:13:50 EST


... and make it depend on the response flag instead of the command type.

Signed-off-by: Nicolas Pitre <npitre@xxxxxxxxxx>
---

On Sat, 12 May 2007, Pierre Ossman wrote:
> Nicolas Pitre wrote:
> > Please apply the following patch. It is compile tested only as I don't
> > have PXA27x hardware with MMC at the moment, but it just cannot be worse
> > than the current code even when it was compiling.
> >
> >
>
> I would think that it would be better to look at just MMC_RSP_136 and
> MMC_RSP_CRC in case we get future variations.

Makes sense.

diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
index d97d386..f8985c5 100644
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -232,20 +232,14 @@ static int pxamci_cmd_done(struct pxamci_host *host, unsigned int stat)
/*
* workaround for erratum #42:
* Intel PXA27x Family Processor Specification Update Rev 001
+ * A bogus CRC error can appear if the msb of a 136 bit
+ * response is a one.
*/
- if (cmd->opcode == MMC_ALL_SEND_CID ||
- cmd->opcode == MMC_SEND_CSD ||
- cmd->opcode == MMC_SEND_CID) {
- /* a bogus CRC error can appear if the msb of
- the 15 byte response is a one */
- if ((cmd->resp[0] & 0x80000000) == 0)
- cmd->error = MMC_ERR_BADCRC;
- } else {
- pr_debug("ignoring CRC from command %d - *risky*\n",cmd->opcode);
- }
-#else
- cmd->error = MMC_ERR_BADCRC;
+ if (cmd->flags & MMC_RSP_136 && cmd->resp[0] & 0x80000000) {
+ pr_debug("ignoring CRC from command %d - *risky*\n", cmd->opcode);
+ } else
#endif
+ cmd->error = MMC_ERR_BADCRC;
}

pxamci_disable_irq(host, END_CMD_RES);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/