Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: (75 commits)
  mmc: core: eMMC bus width may not work on all platforms
  mmc: sdhci: Auto-CMD23 fixes.
  mmc: sdhci: Auto-CMD23 support.
  mmc: core: Block CMD23 support for UHS104/SDXC cards.
  mmc: sdhci: Implement MMC_CAP_CMD23 for SDHCI.
  mmc: core: Use CMD23 for multiblock transfers when we can.
  mmc: quirks: Add/remove quirks conditional support.
  mmc: Add new VUB300 USB-to-SD/SDIO/MMC driver
  mmc: sdhci-pxa: Add quirks for DMA/ADMA to match h/w
  mmc: core: duplicated trial with same freq in mmc_rescan_try_freq()
  mmc: core: add support for eMMC Dual Data Rate
  mmc: core: eMMC signal voltage does not use CMD11
  mmc: sdhci-pxa: add platform code for UHS signaling
  mmc: sdhci: add hooks for setting UHS in platform specific code
  mmc: core: clear MMC_PM_KEEP_POWER flag on resume
  mmc: dw_mmc: fixed wrong regulator_enable in suspend/resume
  mmc: sdhi: allow powering down controller with no card inserted
  mmc: tmio: runtime suspend the controller, where possible
  mmc: sdhi: support up to 3 interrupt sources
  mmc: sdhi: print physical base address and clock rate
  ...

1 files changed, 27 insertions, 0 deletions

diff --git a/Documentation/mmc/mmc-dev-parts.txt b/Documentation/mmc/mmc-dev-parts.txt
new file mode 100644
index 000000000000..2db28b8e662f
--- /dev/null
+++ b/Documentation/mmc/mmc-dev-parts.txt
@@ -0,0 +1,27 @@
+SD and MMC Device Partitions
+============================
+
+Device partitions are additional logical block devices present on the
+SD/MMC device.
+
+As of this writing, MMC boot partitions as supported and exposed as
+/dev/mmcblkXboot0 and /dev/mmcblkXboot1, where X is the index of the
+parent /dev/mmcblkX.
+
+MMC Boot Partitions
+===================
+
+Read and write access is provided to the two MMC boot partitions. Due to
+the sensitive nature of the boot partition contents, which often store
+a bootloader or bootloader configuration tables crucial to booting the
+platform, write access is disabled by default to reduce the chance of
+accidental bricking.
+
+To enable write access to /dev/mmcblkXbootY, disable the forced read-only
+access with:
+
+echo 0 > /sys/block/mmcblkXbootY/force_ro
+
+To re-enable read-only access:
+
+echo 1 > /sys/block/mmcblkXbootY/force_ro