Re: [PATCH][MMC] Fix wrong EXT_CSD_REV handling

[Kyungmin Park]

On Dec 13, 2007 4:53 PM, Pierre Ossman <drzeus-list@xxxxxxxxx> wrote:
> On Thu, 13 Dec 2007 16:13:11 +0900
> Kyungmin Park <kyungmin.park@xxxxxxxxxxx> wrote:
>
> > It already checked the ext_csd_struct is less than 2,
> > so it doesn't need to check it.
> > Current code only accepts the revision 1.2.
> >
> > Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
>
> It wasn't wrong the last time you brought this up, and it still isn't wrong. Those bits aren't defined until version 1.2 of the EXT_CSD register, hence we do not trust them. If you have some broken card that you feel you must have support for, then start working on some quirks system.

Now see the code.

First, it checks the ext_csd_struct.
       ext_csd_struct = ext_csd[EXT_CSD_REV];
        if (ext_csd_struct > 2) {
                printk(KERN_ERR "%s: unrecognised EXT_CSD structure "
                        "version %d\n", mmc_hostname(card->host),
                        ext_csd_struct);
                err = -EINVAL;
                goto out;
        }
        => here possible values are 0, 1, 2

        => It only accepts the ext_csd 2 but my *broken* card has 1.
so it's failed.
        if (ext_csd_struct >= 2) {
                card->ext_csd.sectors =
                        ext_csd[EXT_CSD_SEC_CNT + 0] << 0 |
                        ext_csd[EXT_CSD_SEC_CNT + 1] << 8 |
                        ext_csd[EXT_CSD_SEC_CNT + 2] << 16 |
                        ext_csd[EXT_CSD_SEC_CNT + 3] << 24;
                if (card->ext_csd.sectors)
                        mmc_card_set_blockaddr(card);
        }

In my MMC Spec. (v4.2), there's no problem to read it even though it's
revision 1.1

Anyway how do it handle this one? Do you have any idea?

Thank you,
Kyungmin Park
--
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/