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Documentation / laptops / acer-wmi.txt


Based on kernel version 2.6.39.1. Page generated on 2011-06-03 13:47 EST.

1	Acer Laptop WMI Extras Driver
2	http://code.google.com/p/aceracpi
3	Version 0.3
4	4th April 2009
5	
6	Copyright 2007-2009 Carlos Corbacho <carlos@strangeworlds.co.uk>
7	
8	acer-wmi is a driver to allow you to control various parts of your Acer laptop
9	hardware under Linux which are exposed via ACPI-WMI.
10	
11	This driver completely replaces the old out-of-tree acer_acpi, which I am
12	currently maintaining for bug fixes only on pre-2.6.25 kernels. All development
13	work is now focused solely on acer-wmi.
14	
15	Disclaimer
16	**********
17	
18	Acer and Wistron have provided nothing towards the development acer_acpi or
19	acer-wmi. All information we have has been through the efforts of the developers
20	and the users to discover as much as possible about the hardware.
21	
22	As such, I do warn that this could break your hardware - this is extremely
23	unlikely of course, but please bear this in mind.
24	
25	Background
26	**********
27	
28	acer-wmi is derived from acer_acpi, originally developed by Mark
29	Smith in 2005, then taken over by Carlos Corbacho in 2007, in order to activate
30	the wireless LAN card under a 64-bit version of Linux, as acerhk[1] (the
31	previous solution to the problem) relied on making 32 bit BIOS calls which are
32	not possible in kernel space from a 64 bit OS.
33	
34	[1] acerhk: http://www.cakey.de/acerhk/
35	
36	Supported Hardware
37	******************
38	
39	NOTE: The Acer Aspire One is not supported hardware. It cannot work with
40	acer-wmi until Acer fix their ACPI-WMI implementation on them, so has been
41	blacklisted until that happens.
42	
43	Please see the website for the current list of known working hardware:
44	
45	http://code.google.com/p/aceracpi/wiki/SupportedHardware
46	
47	If your laptop is not listed, or listed as unknown, and works with acer-wmi,
48	please contact me with a copy of the DSDT.
49	
50	If your Acer laptop doesn't work with acer-wmi, I would also like to see the
51	DSDT.
52	
53	To send me the DSDT, as root/sudo:
54	
55	cat /sys/firmware/acpi/tables/DSDT > dsdt
56	
57	And send me the resulting 'dsdt' file.
58	
59	Usage
60	*****
61	
62	On Acer laptops, acer-wmi should already be autoloaded based on DMI matching.
63	For non-Acer laptops, until WMI based autoloading support is added, you will
64	need to manually load acer-wmi.
65	
66	acer-wmi creates /sys/devices/platform/acer-wmi, and fills it with various
67	files whose usage is detailed below, which enables you to control some of the
68	following (varies between models):
69	
70	* the wireless LAN card radio
71	* inbuilt Bluetooth adapter
72	* inbuilt 3G card
73	* mail LED of your laptop
74	* brightness of the LCD panel
75	
76	Wireless
77	********
78	
79	With regards to wireless, all acer-wmi does is enable the radio on the card. It
80	is not responsible for the wireless LED - once the radio is enabled, this is
81	down to the wireless driver for your card. So the behaviour of the wireless LED,
82	once you enable the radio, will depend on your hardware and driver combination.
83	
84	e.g. With the BCM4318 on the Acer Aspire 5020 series:
85	
86	ndiswrapper: Light blinks on when transmitting
87	b43: Solid light, blinks off when transmitting
88	
89	Wireless radio control is unconditionally enabled - all Acer laptops that support
90	acer-wmi come with built-in wireless. However, should you feel so inclined to
91	ever wish to remove the card, or swap it out at some point, please get in touch
92	with me, as we may well be able to gain some data on wireless card detection.
93	
94	The wireless radio is exposed through rfkill.
95	
96	Bluetooth
97	*********
98	
99	For bluetooth, this is an internal USB dongle, so once enabled, you will get
100	a USB device connection event, and a new USB device appears. When you disable
101	bluetooth, you get the reverse - a USB device disconnect event, followed by the
102	device disappearing again.
103	
104	Bluetooth is autodetected by acer-wmi, so if you do not have a bluetooth module
105	installed in your laptop, this file won't exist (please be aware that it is
106	quite common for Acer not to fit bluetooth to their laptops - so just because
107	you have a bluetooth button on the laptop, doesn't mean that bluetooth is
108	installed).
109	
110	For the adventurously minded - if you want to buy an internal bluetooth
111	module off the internet that is compatible with your laptop and fit it, then
112	it will work just fine with acer-wmi.
113	
114	Bluetooth is exposed through rfkill.
115	
116	3G
117	**
118	
119	3G is currently not autodetected, so the 'threeg' file is always created under
120	sysfs. So far, no-one in possession of an Acer laptop with 3G built-in appears to
121	have tried Linux, or reported back, so we don't have any information on this.
122	
123	If you have an Acer laptop that does have a 3G card in, please contact me so we
124	can properly detect these, and find out a bit more about them.
125	
126	To read the status of the 3G card (0=off, 1=on):
127	cat /sys/devices/platform/acer-wmi/threeg
128	
129	To enable the 3G card:
130	echo 1 > /sys/devices/platform/acer-wmi/threeg
131	
132	To disable the 3G card:
133	echo 0 > /sys/devices/platform/acer-wmi/threeg
134	
135	To set the state of the 3G card when loading acer-wmi, pass:
136	threeg=X (where X is 0 or 1)
137	
138	Mail LED
139	********
140	
141	This can be found in most older Acer laptops supported by acer-wmi, and many
142	newer ones - it is built into the 'mail' button, and blinks when active.
143	
144	On newer (WMID) laptops though, we have no way of detecting the mail LED. If
145	your laptop identifies itself in dmesg as a WMID model, then please try loading
146	acer_acpi with:
147	
148	force_series=2490
149	
150	This will use a known alternative method of reading/ writing the mail LED. If
151	it works, please report back to me with the DMI data from your laptop so this
152	can be added to acer-wmi.
153	
154	The LED is exposed through the LED subsystem, and can be found in:
155	
156	/sys/devices/platform/acer-wmi/leds/acer-wmi::mail/
157	
158	The mail LED is autodetected, so if you don't have one, the LED device won't
159	be registered.
160	
161	Backlight
162	*********
163	
164	The backlight brightness control is available on all acer-wmi supported
165	hardware. The maximum brightness level is usually 15, but on some newer laptops
166	it's 10 (this is again autodetected).
167	
168	The backlight is exposed through the backlight subsystem, and can be found in:
169	
170	/sys/devices/platform/acer-wmi/backlight/acer-wmi/
171	
172	Credits
173	*******
174	
175	Olaf Tauber, who did the real hard work when he developed acerhk
176	http://www.cakey.de/acerhk/
177	All the authors of laptop ACPI modules in the kernel, whose work
178	was an inspiration in the early days of acer_acpi
179	Mathieu Segaud, who solved the problem with having to modprobe the driver
180	twice in acer_acpi 0.2.
181	Jim Ramsay, who added support for the WMID interface
182	Mark Smith, who started the original acer_acpi
183	
184	And the many people who have used both acer_acpi and acer-wmi.
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