aboutsummaryrefslogtreecommitdiff
path: root/Documentation
diff options
context:
space:
mode:
authorChuanxiao Dong <chuanxiao.dong@intel.com>2011-01-22 04:09:41 +0800
committerChris Ball <cjb@laptop.org>2011-03-15 13:48:01 -0400
commit709de99df0ecf3102e7728fbd876a3591859f423 (patch)
treef1adaa026531d3dcc93cf33c2e8ede84455ca46a /Documentation
parentcfd80652467717ca7346857d6d8c94503d74f3a3 (diff)
downloadlinux-linaro-android-709de99df0ecf3102e7728fbd876a3591859f423.tar.gz
mmc: export eMMC4.4 enhanced area details to sysfs
Enhanced area feature is a new feature defined in eMMC4.4 standard. This user data area provides higher performance/reliability, at the expense of using twice the effective media space due to the area using SLC. The MMC driver now reads out the enhanced area offset and size and adds them to the device attributes in sysfs. Enabling the enhanced area can only be done once, and should be done in manufacturing. To use this feature, bit ERASE_GRP_DEF should also be set. Documentation/ABI/testing/sysfs-devices-mmc describes the two new attributes. Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com> Reviewed-by: Chris Ball <cjb@laptop.org> Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/testing/sysfs-devices-mmc21
1 files changed, 21 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-mmc b/Documentation/ABI/testing/sysfs-devices-mmc
new file mode 100644
index 00000000000..5a50ab65584
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-mmc
@@ -0,0 +1,21 @@
+What: /sys/devices/.../mmc_host/mmcX/mmcX:XXXX/enhanced_area_offset
+Date: January 2011
+Contact: Chuanxiao Dong <chuanxiao.dong@intel.com>
+Description:
+ Enhanced area is a new feature defined in eMMC4.4 standard.
+ eMMC4.4 or later card can support such feature. This kind of
+ area can help to improve the card performance. If the feature
+ is enabled, this attribute will indicate the start address of
+ enhanced data area. If not, this attribute will be -EINVAL.
+ Unit Byte. Format decimal.
+
+What: /sys/devices/.../mmc_host/mmcX/mmcX:XXXX/enhanced_area_size
+Date: January 2011
+Contact: Chuanxiao Dong <chuanxiao.dong@intel.com>
+Description:
+ Enhanced area is a new feature defined in eMMC4.4 standard.
+ eMMC4.4 or later card can support such feature. This kind of
+ area can help to improve the card performance. If the feature
+ is enabled, this attribute will indicate the size of enhanced
+ data area. If not, this attribute will be -EINVAL.
+ Unit KByte. Format decimal.