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Hi Pierre, Pierre Ossman wrote: > Suggested patch included. What's the status on this patch? A Gentoo user at http://bugs.gentoo.org/142172 reports that it is required for him to be able to access his card, so it definitely works in some form. > > [MMC] Always use a sector size of 512 bytes > > Both MMC and SD specifications specify (although a bit unclearly in the MMC > case) that a sector size of 512 bytes must always be supported by the card. > > Cards can report larger "native" size than this, and cards >= 2 GB even > must do so. Most other readers use 512 bytes even for these cards. We should > do the same to be compatible. > > Signed-off-by: Pierre Ossman <drzeus@drzeus.cx> > --- > > drivers/mmc/mmc_block.c | 49 ++++------------------------------------------- > 1 files changed, 4 insertions(+), 45 deletions(-) > > diff --git a/drivers/mmc/mmc_block.c b/drivers/mmc/mmc_block.c > index 587458b..96049e2 100644 > --- a/drivers/mmc/mmc_block.c > +++ b/drivers/mmc/mmc_block.c > @@ -325,52 +325,11 @@ static struct mmc_blk_data *mmc_blk_allo > md->read_only = mmc_blk_readonly(card); > > /* > - * Figure out a workable block size. MMC cards have: > - * - two block sizes, one for read and one for write. > - * - may support partial reads and/or writes > - * (allows block sizes smaller than specified) > + * Both SD and MMC specifications state (although a bit > + * unclearly in the MMC case) that a block size of 512 > + * bytes must always be supported by the card. > */ > - md->block_bits = card->csd.read_blkbits; > - if (card->csd.write_blkbits != card->csd.read_blkbits) { > - if (card->csd.write_blkbits < card->csd.read_blkbits && > - card->csd.read_partial) { > - /* > - * write block size is smaller than read block > - * size, but we support partial reads, so choose > - * the smaller write block size. > - */ > - md->block_bits = card->csd.write_blkbits; > - } else if (card->csd.write_blkbits > card->csd.read_blkbits && > - card->csd.write_partial) { > - /* > - * read block size is smaller than write block > - * size, but we support partial writes. Use read > - * block size. > - */ > - } else { > - /* > - * We don't support this configuration for writes. > - */ > - printk(KERN_ERR "%s: unable to select block size for " > - "writing (rb%u wb%u rp%u wp%u)\n", > - mmc_card_id(card), > - 1 << card->csd.read_blkbits, > - 1 << card->csd.write_blkbits, > - card->csd.read_partial, > - card->csd.write_partial); > - md->read_only = 1; > - } > - } > - > - /* > - * Refuse to allow block sizes smaller than 512 bytes. > - */ > - if (md->block_bits < 9) { > - printk(KERN_ERR "%s: unable to support block size %u\n", > - mmc_card_id(card), 1 << md->block_bits); > - ret = -EINVAL; > - goto err_kfree; > - } > + md->block_bits = 9; > > md->disk = alloc_disk(1 << MMC_SHIFT); > if (md->disk == NULL) { - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | ||||||||||
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