1========================================= 2Sony Notebook Control Driver (SNC) Readme 3========================================= 4 5 - Copyright (C) 2004- 2005 Stelian Pop <stelian@popies.net> 6 - Copyright (C) 2007 Mattia Dongili <malattia@linux.it> 7 8This mini-driver drives the SNC and SPIC device present in the ACPI BIOS of the 9Sony Vaio laptops. This driver mixes both devices functions under the same 10(hopefully consistent) interface. This also means that the sonypi driver is 11obsoleted by sony-laptop now. 12 13Fn keys (hotkeys): 14------------------ 15 16Some models report hotkeys through the SNC or SPIC devices, such events are 17reported both through the ACPI subsystem as acpi events and through the INPUT 18subsystem. See the logs of /proc/bus/input/devices to find out what those 19events are and which input devices are created by the driver. 20Additionally, loading the driver with the debug option will report all events 21in the kernel log. 22 23The "scancodes" passed to the input system (that can be remapped with udev) 24are indexes to the table "sony_laptop_input_keycode_map" in the sony-laptop.c 25module. For example the "FN/E" key combination (EJECTCD on some models) 26generates the scancode 20 (0x14). 27 28Backlight control: 29------------------ 30If your laptop model supports it, you will find sysfs files in the 31/sys/class/backlight/sony/ 32directory. You will be able to query and set the current screen 33brightness: 34 35 ====================== ========================================= 36 brightness get/set screen brightness (an integer 37 between 0 and 7) 38 actual_brightness reading from this file will query the HW 39 to get real brightness value 40 max_brightness the maximum brightness value 41 ====================== ========================================= 42 43 44Platform specific: 45------------------ 46Loading the sony-laptop module will create a 47/sys/devices/platform/sony-laptop/ 48directory populated with some files. 49 50You then read/write integer values from/to those files by using 51standard UNIX tools. 52 53The files are: 54 55 ====================== ========================================== 56 brightness_default screen brightness which will be set 57 when the laptop will be rebooted 58 cdpower power on/off the internal CD drive 59 audiopower power on/off the internal sound card 60 lanpower power on/off the internal ethernet card 61 (only in debug mode) 62 bluetoothpower power on/off the internal bluetooth device 63 fanspeed get/set the fan speed 64 ====================== ========================================== 65 66Note that some files may be missing if they are not supported 67by your particular laptop model. 68 69Example usage:: 70 71 # echo "1" > /sys/devices/platform/sony-laptop/brightness_default 72 73sets the lowest screen brightness for the next and later reboots 74 75:: 76 77 # echo "8" > /sys/devices/platform/sony-laptop/brightness_default 78 79sets the highest screen brightness for the next and later reboots 80 81:: 82 83 # cat /sys/devices/platform/sony-laptop/brightness_default 84 85retrieves the value 86 87:: 88 89 # echo "0" > /sys/devices/platform/sony-laptop/audiopower 90 91powers off the sound card 92 93:: 94 95 # echo "1" > /sys/devices/platform/sony-laptop/audiopower 96 97powers on the sound card. 98 99 100RFkill control: 101--------------- 102More recent Vaio models expose a consistent set of ACPI methods to 103control radio frequency emitting devices. If you are a lucky owner of 104such a laptop you will find the necessary rfkill devices under 105/sys/class/rfkill. Check those starting with sony-* in:: 106 107 # grep . /sys/class/rfkill/*/{state,name} 108 109 110Development: 111------------ 112 113If you want to help with the development of this driver (and 114you are not afraid of any side effects doing strange things with 115your ACPI BIOS could have on your laptop), load the driver and 116pass the option 'debug=1'. 117 118REPEAT: 119 **DON'T DO THIS IF YOU DON'T LIKE RISKY BUSINESS.** 120 121In your kernel logs you will find the list of all ACPI methods 122the SNC device has on your laptop. 123 124* For new models you will see a long list of meaningless method names, 125 reading the DSDT table source should reveal that: 126 127(1) the SNC device uses an internal capability lookup table 128(2) SN00 is used to find values in the lookup table 129(3) SN06 and SN07 are used to call into the real methods based on 130 offsets you can obtain iterating the table using SN00 131(4) SN02 used to enable events. 132 133Some values in the capability lookup table are more or less known, see 134the code for all sony_call_snc_handle calls, others are more obscure. 135 136* For old models you can see the GCDP/GCDP methods used to pwer on/off 137 the CD drive, but there are others and they are usually different from 138 model to model. 139 140**I HAVE NO IDEA WHAT THOSE METHODS DO.** 141 142The sony-laptop driver creates, for some of those methods (the most 143current ones found on several Vaio models), an entry under 144/sys/devices/platform/sony-laptop, just like the 'cdpower' one. 145You can create other entries corresponding to your own laptop methods by 146further editing the source (see the 'sony_nc_values' table, and add a new 147entry to this table with your get/set method names using the 148SNC_HANDLE_NAMES macro). 149 150Your mission, should you accept it, is to try finding out what 151those entries are for, by reading/writing random values from/to those 152files and find out what is the impact on your laptop. 153 154Should you find anything interesting, please report it back to me, 155I will not disavow all knowledge of your actions :) 156 157See also http://www.linux.it/~malattia/wiki/index.php/Sony_drivers for other 158useful info. 159 160Bugs/Limitations: 161----------------- 162 163* This driver is not based on official documentation from Sony 164 (because there is none), so there is no guarantee this driver 165 will work at all, or do the right thing. Although this hasn't 166 happened to me, this driver could do very bad things to your 167 laptop, including permanent damage. 168 169* The sony-laptop and sonypi drivers do not interact at all. In the 170 future, sonypi will be removed and replaced by sony-laptop. 171 172* spicctrl, which is the userspace tool used to communicate with the 173 sonypi driver (through /dev/sonypi) is deprecated as well since all 174 its features are now available under the sysfs tree via sony-laptop. 175