diff options
Diffstat (limited to 'Documentation/ABI/testing')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-i3c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-i3c b/Documentation/ABI/testing/sysfs-bus-i3c index c1e048957a01..19f5cf8b1b11 100644 --- a/Documentation/ABI/testing/sysfs-bus-i3c +++ b/Documentation/ABI/testing/sysfs-bus-i3c @@ -172,3 +172,23 @@ Description: the automatic retries. Exist only when I3C constroller supports this retry on nack feature. +What: /sys/bus/i3c/devices/i3c-<bus-id>/do_daa +KernelVersion: 7.0 +Contact: linux-i3c@vger.kernel.org +Description: + Write-only attribute that triggers a Dynamic Address Assignment + (DAA) procedure which discovers new I3C devices on the bus. + Writing a boolean true value (1, y, yes, true, on) to this + attribute causes the master controller to perform DAA, which + includes broadcasting an ENTDAA (Enter Dynamic Address Assignment) + Common Command Code (CCC) on the bus. Writing a false value + returns -EINVAL. + + This is useful for discovering I3C devices that were not present + during initial bus initialization and are unable to issue + Hot-Join. Only devices without a currently assigned dynamic address + will respond to the ENTDAA broadcast and be assigned addresses. + + Note that this mechanism is distinct from Hot-Join, since this is + controller-initiated discovery, while Hot-Join is device-initiated + method to provoke controller discovery procedure. |