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diff --git a/Documentation/admin-guide/laptops/sony-laptop.rst b/Documentation/admin-guide/laptops/sony-laptop.rst new file mode 100644 index 0000000000..9edcc7f661 --- /dev/null +++ b/Documentation/admin-guide/laptops/sony-laptop.rst @@ -0,0 +1,174 @@ +========================================= +Sony Notebook Control Driver (SNC) Readme +========================================= + + - Copyright (C) 2004- 2005 Stelian Pop <stelian@popies.net> + - Copyright (C) 2007 Mattia Dongili <malattia@linux.it> + +This mini-driver drives the SNC and SPIC device present in the ACPI BIOS of the +Sony Vaio laptops. This driver mixes both devices functions under the same +(hopefully consistent) interface. This also means that the sonypi driver is +obsoleted by sony-laptop now. + +Fn keys (hotkeys): +------------------ + +Some models report hotkeys through the SNC or SPIC devices, such events are +reported both through the ACPI subsystem as acpi events and through the INPUT +subsystem. See the logs of /proc/bus/input/devices to find out what those +events are and which input devices are created by the driver. +Additionally, loading the driver with the debug option will report all events +in the kernel log. + +The "scancodes" passed to the input system (that can be remapped with udev) +are indexes to the table "sony_laptop_input_keycode_map" in the sony-laptop.c +module. For example the "FN/E" key combination (EJECTCD on some models) +generates the scancode 20 (0x14). + +Backlight control: +------------------ +If your laptop model supports it, you will find sysfs files in the +/sys/class/backlight/sony/ +directory. You will be able to query and set the current screen +brightness: + + ====================== ========================================= + brightness get/set screen brightness (an integer + between 0 and 7) + actual_brightness reading from this file will query the HW + to get real brightness value + max_brightness the maximum brightness value + ====================== ========================================= + + +Platform specific: +------------------ +Loading the sony-laptop module will create a +/sys/devices/platform/sony-laptop/ +directory populated with some files. + +You then read/write integer values from/to those files by using +standard UNIX tools. + +The files are: + + ====================== ========================================== + brightness_default screen brightness which will be set + when the laptop will be rebooted + cdpower power on/off the internal CD drive + audiopower power on/off the internal sound card + lanpower power on/off the internal ethernet card + (only in debug mode) + bluetoothpower power on/off the internal bluetooth device + fanspeed get/set the fan speed + ====================== ========================================== + +Note that some files may be missing if they are not supported +by your particular laptop model. + +Example usage:: + + # echo "1" > /sys/devices/platform/sony-laptop/brightness_default + +sets the lowest screen brightness for the next and later reboots + +:: + + # echo "8" > /sys/devices/platform/sony-laptop/brightness_default + +sets the highest screen brightness for the next and later reboots + +:: + + # cat /sys/devices/platform/sony-laptop/brightness_default + +retrieves the value + +:: + + # echo "0" > /sys/devices/platform/sony-laptop/audiopower + +powers off the sound card + +:: + + # echo "1" > /sys/devices/platform/sony-laptop/audiopower + +powers on the sound card. + + +RFkill control: +--------------- +More recent Vaio models expose a consistent set of ACPI methods to +control radio frequency emitting devices. If you are a lucky owner of +such a laptop you will find the necessary rfkill devices under +/sys/class/rfkill. Check those starting with sony-* in:: + + # grep . /sys/class/rfkill/*/{state,name} + + +Development: +------------ + +If you want to help with the development of this driver (and +you are not afraid of any side effects doing strange things with +your ACPI BIOS could have on your laptop), load the driver and +pass the option 'debug=1'. + +REPEAT: + **DON'T DO THIS IF YOU DON'T LIKE RISKY BUSINESS.** + +In your kernel logs you will find the list of all ACPI methods +the SNC device has on your laptop. + +* For new models you will see a long list of meaningless method names, + reading the DSDT table source should reveal that: + +(1) the SNC device uses an internal capability lookup table +(2) SN00 is used to find values in the lookup table +(3) SN06 and SN07 are used to call into the real methods based on + offsets you can obtain iterating the table using SN00 +(4) SN02 used to enable events. + +Some values in the capability lookup table are more or less known, see +the code for all sony_call_snc_handle calls, others are more obscure. + +* For old models you can see the GCDP/GCDP methods used to pwer on/off + the CD drive, but there are others and they are usually different from + model to model. + +**I HAVE NO IDEA WHAT THOSE METHODS DO.** + +The sony-laptop driver creates, for some of those methods (the most +current ones found on several Vaio models), an entry under +/sys/devices/platform/sony-laptop, just like the 'cdpower' one. +You can create other entries corresponding to your own laptop methods by +further editing the source (see the 'sony_nc_values' table, and add a new +entry to this table with your get/set method names using the +SNC_HANDLE_NAMES macro). + +Your mission, should you accept it, is to try finding out what +those entries are for, by reading/writing random values from/to those +files and find out what is the impact on your laptop. + +Should you find anything interesting, please report it back to me, +I will not disavow all knowledge of your actions :) + +See also http://www.linux.it/~malattia/wiki/index.php/Sony_drivers for other +useful info. + +Bugs/Limitations: +----------------- + +* This driver is not based on official documentation from Sony + (because there is none), so there is no guarantee this driver + will work at all, or do the right thing. Although this hasn't + happened to me, this driver could do very bad things to your + laptop, including permanent damage. + +* The sony-laptop and sonypi drivers do not interact at all. In the + future, sonypi will be removed and replaced by sony-laptop. + +* spicctrl, which is the userspace tool used to communicate with the + sonypi driver (through /dev/sonypi) is deprecated as well since all + its features are now available under the sysfs tree via sony-laptop. |