xref: /linux/Documentation/ABI/stable/sysfs-bus-mhi (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1What:		/sys/bus/mhi/devices/.../serialnumber
2Date:		Sept 2020
3KernelVersion:	5.10
4Contact:	mhi@lists.linux.dev
5Description:	The file holds the serial number of the client device obtained
6		using a BHI (Boot Host Interface) register read after at least
7		one attempt to power up the device has been done. If read
8		without having the device power on at least once, the file will
9		read all 0's.
10Users:		Any userspace application or clients interested in device info.
11
12What:		/sys/bus/mhi/devices/.../oem_pk_hash
13Date:		Sept 2020
14KernelVersion:	5.10
15Contact:	mhi@lists.linux.dev
16Description:	The file holds the OEM PK Hash value of the endpoint device
17		obtained using a BHI (Boot Host Interface) register read after
18		at least one attempt to power up the device has been done. If
19		read without having the device power on at least once, the file
20		will read all 0's.
21Users:		Any userspace application or clients interested in device info.
22
23What:           /sys/bus/mhi/devices/.../soc_reset
24Date:           April 2022
25KernelVersion:  5.19
26Contact:        mhi@lists.linux.dev
27Description:	Initiates a SoC reset on the MHI controller.  A SoC reset is
28                a reset of last resort, and will require a complete re-init.
29                This can be useful as a method of recovery if the device is
30                non-responsive, or as a means of loading new firmware as a
31                system administration task.
32
33What:           /sys/bus/mhi/devices/.../trigger_edl
34Date:           April 2024
35KernelVersion:  6.10
36Contact:        mhi@lists.linux.dev
37Description:    Writing a non-zero value to this file will force devices to
38                enter EDL (Emergency Download) mode. This entry only exists for
39                devices capable of entering the EDL mode using the standard EDL
40                triggering mechanism defined in the MHI spec v1.2. Once in EDL
41                mode, the flash programmer image can be downloaded to the
42                device to enter the flash programmer execution environment.
43                This can be useful if user wants to use QDL (Qualcomm Download,
44                which is used to download firmware over EDL) to update firmware.
45