Kernel fails to find devices to mount

[Dmitry Dagunts]

I posted more info here: https://github.com/ddagunts/UTCWM_N7_patch

Long story short, newer Nexus 7 "flo" models, made in/after late 2014 have a different revision to their eMMC controller/hardware/something. This causes Ubuntu Touch to fail to boot (or enter recovery). A kernel with the following patch is needed:
```
mmc: add 5.0 emmc support

bug: 17968808 Kernel change for new eMMC v5.0 parts for FLO/DEB

Change-Id: Ia18152457fe3ff70401b199c267fa37374b9d544
Signed-off-by: hsuan-chih_chen <email address hidden>
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index dc4b125..ea1eca7 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -293,7 +293,7 @@
    }

    card->ext_csd.rev = ext_csd[EXT_CSD_REV];
- if (card->ext_csd.rev > 6) {
+ if (card->ext_csd.rev > 7) {
        pr_err("%s: unrecognised EXT_CSD revision %d\n",
            mmc_hostname(card->host), card->ext_csd.rev);
        err = -EINVAL;
```

I answered a question about this here: http://askubuntu.com/questions/674179/ubuntu-device-flash-fails-on-nexus-7-2013-android-5-0-2-cant-copy-image-to

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Modestas (montvid)]

the bug is resolved in official kernel, proper 5.0 emmc support is added see mmc.c:

/* eMMC v5 or later */
 if (card->ext_csd.rev >= 7) {
  memcpy(card->ext_csd.fwrev, &ext_csd[EXT_CSD_FIRMWARE_VERSION],
         MMC_FIRMWARE_LEN);
  card->ext_csd.ffu_capable =
   (ext_csd[EXT_CSD_SUPPORTED_MODE] & 0x1) &&
   !(ext_csd[EXT_CSD_FW_CONFIG] & 0x1);

  card->ext_csd.pre_eol_info = ext_csd[EXT_CSD_PRE_EOL_INFO];
  card->ext_csd.device_life_time_est_typ_a =
   ext_csd[EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_A];
  card->ext_csd.device_life_time_est_typ_b =
   ext_csd[EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_B];
 }

Please support flo again! :)