summaryrefslogtreecommitdiffstats
path: root/Documentation/i2c/ten-bit-addresses
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/i2c/ten-bit-addresses')
-rw-r--r--Documentation/i2c/ten-bit-addresses4
1 files changed, 4 insertions, 0 deletions
diff --git a/Documentation/i2c/ten-bit-addresses b/Documentation/i2c/ten-bit-addresses
index cdfe13901b99..7b2d11e53a49 100644
--- a/Documentation/i2c/ten-bit-addresses
+++ b/Documentation/i2c/ten-bit-addresses
@@ -2,6 +2,10 @@ The I2C protocol knows about two kinds of device addresses: normal 7 bit
addresses, and an extended set of 10 bit addresses. The sets of addresses
do not intersect: the 7 bit address 0x10 is not the same as the 10 bit
address 0x10 (though a single device could respond to both of them).
+To avoid ambiguity, the user sees 10 bit addresses mapped to a different
+address space, namely 0xa000-0xa3ff. The leading 0xa (= 10) represents the
+10 bit mode. This is used for creating device names in sysfs. It is also
+needed when instantiating 10 bit devices via the new_device file in sysfs.
I2C messages to and from 10-bit address devices have a different format.
See the I2C specification for the details.