xref: /linux/Documentation/ABI/testing/sysfs-class-firmware (revision 2a6b6c9a226279b4f6668450ddb21ae655558087)
1What: 		/sys/class/firmware/.../data
2Date:		July 2022
3KernelVersion:	5.19
4Contact:	Russ Weight <russ.weight@linux.dev>
5Description:	The data sysfs file is used for firmware-fallback and for
6		firmware uploads. Cat a firmware image to this sysfs file
7		after you echo 1 to the loading sysfs file. When the firmware
8		image write is complete, echo 0 to the loading sysfs file. This
9		sequence will signal the completion of the firmware write and
10		signal the lower-level driver that the firmware data is
11		available.
12
13What: 		/sys/class/firmware/.../cancel
14Date:		July 2022
15KernelVersion:	5.19
16Contact:	Russ Weight <russ.weight@linux.dev>
17Description:	Write-only. For firmware uploads, write a "1" to this file to
18		request that the transfer of firmware data to the lower-level
19		device be canceled. This request will be rejected (EBUSY) if
20		the update cannot be canceled (e.g. a FLASH write is in
21		progress) or (ENODEV) if there is no firmware update in progress.
22
23What: 		/sys/class/firmware/.../error
24Date:		July 2022
25KernelVersion:	5.19
26Contact:	Russ Weight <russ.weight@linux.dev>
27Description:	Read-only. Returns a string describing a failed firmware
28		upload. This string will be in the form of <STATUS>:<ERROR>,
29		where <STATUS> will be one of the status strings described
30		for the status sysfs file and <ERROR> will be one of the
31		following: "hw-error", "timeout", "user-abort", "device-busy",
32		"invalid-file-size", "read-write-error", "flash-wearout". The
33		error sysfs file is only meaningful when the current firmware
34		upload status is "idle". If this file is read while a firmware
35		transfer is in progress, then the read will fail with EBUSY.
36
37What: 		/sys/class/firmware/.../loading
38Date:		July 2022
39KernelVersion:	5.19
40Contact:	Russ Weight <russ.weight@linux.dev>
41Description:	The loading sysfs file is used for both firmware-fallback and
42		for firmware uploads. Echo 1 onto the loading file to indicate
43		you are writing a firmware file to the data sysfs node. Echo
44		-1 onto this file to abort the data write or echo 0 onto this
45		file to indicate that the write is complete. For firmware
46		uploads, the zero value also triggers the transfer of the
47		firmware data to the lower-level device driver.
48
49What: 		/sys/class/firmware/.../remaining_size
50Date:		July 2022
51KernelVersion:	5.19
52Contact:	Russ Weight <russ.weight@linux.dev>
53Description:	Read-only. For firmware upload, this file contains the size
54		of the firmware data that remains to be transferred to the
55		lower-level device driver. The size value is initialized to
56		the full size of the firmware image that was previously
57		written to the data sysfs file. This value is periodically
58		updated during the "transferring" phase of the firmware
59		upload.
60		Format: "%u".
61
62What: 		/sys/class/firmware/.../status
63Date:		July 2022
64KernelVersion:	5.19
65Contact:	Russ Weight <russ.weight@linux.dev>
66Description:	Read-only. Returns a string describing the current status of
67		a firmware upload. The string will be one of the following:
68		idle, "receiving", "preparing", "transferring", "programming".
69
70What: 		/sys/class/firmware/.../timeout
71Date:		July 2022
72KernelVersion:	5.19
73Contact:	Russ Weight <russ.weight@linux.dev>
74Description:	This file supports the timeout mechanism for firmware
75		fallback.  This file has no affect on firmware uploads. For
76		more information on timeouts please see the documentation
77		for firmware fallback.
78