releases/4.8.5/mmc-block-don-t-use-cmd23-with-very-old-mmc-cards.patch

   1 From 0ed50abb2d8fc81570b53af25621dad560cd49b3 Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Daniel=20Gl=C3=B6ckner?= <dg@emlix.com>
   3 Date: Tue, 30 Aug 2016 14:17:30 +0200
   4 Subject: mmc: block: don't use CMD23 with very old MMC cards
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 From: Daniel Glöckner <dg@emlix.com>
  10
  11 commit 0ed50abb2d8fc81570b53af25621dad560cd49b3 upstream.
  12
  13 CMD23 aka SET_BLOCK_COUNT was introduced with MMC v3.1.
  14 Older versions of the specification allowed to terminate
  15 multi-block transfers only with CMD12.
  16
  17 The patch fixes the following problem:
  18
  19   mmc0: new MMC card at address 0001
  20   mmcblk0: mmc0:0001 SDMB-16 15.3 MiB
  21   mmcblk0: timed out sending SET_BLOCK_COUNT command, card status 0x400900
  22   ...
  23   blk_update_request: I/O error, dev mmcblk0, sector 0
  24   Buffer I/O error on dev mmcblk0, logical block 0, async page read
  25    mmcblk0: unable to read partition table
  26
  27 Signed-off-by: Daniel Glöckner <dg@emlix.com>
  28 Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
  29 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  30
  31 ---
  32  drivers/mmc/card/block.c |    3 ++-
  33  1 file changed, 2 insertions(+), 1 deletion(-)
  34
  35 --- a/drivers/mmc/card/block.c
  36 +++ b/drivers/mmc/card/block.c
  37 @@ -2303,7 +2303,8 @@ again:
  38         set_capacity(md->disk, size);
  39
  40         if (mmc_host_cmd23(card->host)) {
  41 -               if (mmc_card_mmc(card) ||
  42 +               if ((mmc_card_mmc(card) &&
  43 +                    card->csd.mmca_vsn >= CSD_SPEC_VER_3) ||
  44                     (mmc_card_sd(card) &&
  45                      card->scr.cmds & SD_SCR_CMD23_SUPPORT))
  46                         md->flags |= MMC_BLK_CMD23;