1Sony Notebook Control Driver (SNC) Readme 2----------------------------------------- 3 Copyright (C) 2004- 2005 Stelian Pop <stelian@popies.net> 4 Copyright (C) 2007 Mattia Dongili <malattia@linux.it> 5 6This mini-driver drives the SNC and SPIC device present in the ACPI BIOS of the 7Sony Vaio laptops. This driver mixes both devices functions under the same 8(hopefully consistent) interface. This also means that the sonypi driver is 9obsoleted by sony-laptop now. 10 11Fn keys (hotkeys): 12------------------ 13Some models report hotkeys through the SNC or SPIC devices, such events are 14reported both through the ACPI subsystem as acpi events and through the INPUT 15subsystem. See the logs of acpid or /proc/acpi/event and 16/proc/bus/input/devices to find out what those events are and which input 17devices are created by the driver. 18 19Backlight control: 20------------------ 21If your laptop model supports it, you will find sysfs files in the 22/sys/class/backlight/sony/ 23directory. You will be able to query and set the current screen 24brightness: 25 brightness get/set screen brightness (an iteger 26 between 0 and 7) 27 actual_brightness reading from this file will query the HW 28 to get real brightness value 29 max_brightness the maximum brightness value 30 31 32Platform specific: 33------------------ 34Loading the sony-laptop module will create a 35/sys/devices/platform/sony-laptop/ 36directory populated with some files. 37 38You then read/write integer values from/to those files by using 39standard UNIX tools. 40 41The files are: 42 brightness_default screen brightness which will be set 43 when the laptop will be rebooted 44 cdpower power on/off the internal CD drive 45 audiopower power on/off the internal sound card 46 lanpower power on/off the internal ethernet card 47 (only in debug mode) 48 bluetoothpower power on/off the internal bluetooth device 49 fanspeed get/set the fan speed 50 51Note that some files may be missing if they are not supported 52by your particular laptop model. 53 54Example usage: 55 # echo "1" > /sys/devices/platform/sony-laptop/brightness_default 56sets the lowest screen brightness for the next and later reboots, 57 # echo "8" > /sys/devices/platform/sony-laptop/brightness_default 58sets the highest screen brightness for the next and later reboots, 59 # cat /sys/devices/platform/sony-laptop/brightness_default 60retrieves the value. 61 62 # echo "0" > /sys/devices/platform/sony-laptop/audiopower 63powers off the sound card, 64 # echo "1" > /sys/devices/platform/sony-laptop/audiopower 65powers on the sound card. 66 67Development: 68------------ 69 70If you want to help with the development of this driver (and 71you are not afraid of any side effects doing strange things with 72your ACPI BIOS could have on your laptop), load the driver and 73pass the option 'debug=1'. 74 75REPEAT: DON'T DO THIS IF YOU DON'T LIKE RISKY BUSINESS. 76 77In your kernel logs you will find the list of all ACPI methods 78the SNC device has on your laptop. You can see the GCDP/GCDP methods 79used to pwer on/off the CD drive, but there are others. 80 81I HAVE NO IDEA WHAT THOSE METHODS DO. 82 83The sony-laptop driver creates, for some of those methods (the most 84current ones found on several Vaio models), an entry under 85/sys/devices/platform/sony-laptop, just like the 'cdpower' one. 86You can create other entries corresponding to your own laptop methods by 87further editing the source (see the 'sony_nc_values' table, and add a new 88entry to this table with your get/set method names using the 89SNC_HANDLE_NAMES macro). 90 91Your mission, should you accept it, is to try finding out what 92those entries are for, by reading/writing random values from/to those 93files and find out what is the impact on your laptop. 94 95Should you find anything interesting, please report it back to me, 96I will not disavow all knowledge of your actions :) 97 98See also http://www.linux.it/~malattia/wiki/index.php/Sony_drivers for other 99useful info. 100 101Bugs/Limitations: 102----------------- 103 104* This driver is not based on official documentation from Sony 105 (because there is none), so there is no guarantee this driver 106 will work at all, or do the right thing. Although this hasn't 107 happened to me, this driver could do very bad things to your 108 laptop, including permanent damage. 109 110* The sony-laptop and sonypi drivers do not interact at all. In the 111 future, sonypi could use sony-laptop to do (part of) its business. 112 113* spicctrl, which is the userspace tool used to communicate with the 114 sonypi driver (through /dev/sonypi) does not try to use the 115 sony-laptop driver. In the future, spicctrl could try sonypi first, 116 and if it isn't present, try sony-laptop instead. 117