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-rw-r--r--Documentation/mmc/mmc-dev-attrs.txt28
1 files changed, 28 insertions, 0 deletions
diff --git a/Documentation/mmc/mmc-dev-attrs.txt b/Documentation/mmc/mmc-dev-attrs.txt
index ff2bd685bce..189bab09255 100644
--- a/Documentation/mmc/mmc-dev-attrs.txt
+++ b/Documentation/mmc/mmc-dev-attrs.txt
@@ -1,3 +1,13 @@
+SD and MMC Block Device Attributes
+==================================
+
+These attributes are defined for the block devices associated with the
+SD or MMC device.
+
+The following attributes are read/write.
+
+ force_ro Enforce read-only access even if write protect switch is off.
+
SD and MMC Device Attributes
============================
@@ -12,9 +22,12 @@ All attributes are read-only.
manfid Manufacturer ID (from CID Register)
name Product Name (from CID Register)
oemid OEM/Application ID (from CID Register)
+ prv Product Revision (from CID Register) (SD and MMCv4 only)
serial Product Serial Number (from CID Register)
erase_size Erase group size
preferred_erase_size Preferred erase size
+ raw_rpmb_size_mult RPMB partition size
+ rel_sectors Reliable write sector count
Note on Erase Size and Preferred Erase Size:
@@ -54,3 +67,18 @@ Note on Erase Size and Preferred Erase Size:
size specified by the card.
"preferred_erase_size" is in bytes.
+
+Note on raw_rpmb_size_mult:
+ "raw_rpmb_size_mult" is a mutliple of 128kB block.
+ RPMB size in byte is calculated by using the following equation:
+ RPMB partition size = 128kB x raw_rpmb_size_mult
+
+SD/MMC/SDIO Clock Gating Attribute
+==================================
+
+Read and write access is provided to following attribute.
+This attribute appears only if CONFIG_MMC_CLKGATE is enabled.
+
+ clkgate_delay Tune the clock gating delay with desired value in milliseconds.
+
+echo <desired delay> > /sys/class/mmc_host/mmcX/clkgate_delay