Re: Cannot shutdown power use from built in webcam in thinkpad T530 questions]

[Oleksij Rempel <linux@rempel-privat.de>]

Am 28.09.2013 20:08, schrieb Marc MERLIN:
> On Mon, Sep 23, 2013 at 10:21:23AM +0200, Oleksij Rempel wrote:
>>> Understood, just making sure this was still potentially useful considering
>>> what I found out since my last message.
>>
>> Which version of powertop are you actually using? None of current
> 
> The latest, i.e. 2.4.
> 
>> versions would show you Watt usage for devices.
> 
> Sure it does :)
> 
> Summary: 3182.2 wakeups/second,  82.5 GPU ops/seconds, 0.0 VFS ops/sec and 33.5%
> 
> Power est.              Usage       Events/s    Category       Description
>   9.82 W    100.0%                      Device         USB device: Yubico Yubike
>   2.67 W      4.1 ms/s      43.2        Process        /usr/bin/pulseaudio --sta
>   2.58 W    100.0%                      Device         USB device: Integrated Ca
>   2.35 W    100.0%                      Device         USB device: BCM20702A0 (B
>   2.32 W     32.9%                      Device         Display backlight
>   1.39 W    100.0%                      Device         Radio device: btusb
>   343 mW    100.0%                      Device         Radio device: thinkpad_ac

ah ok, i see, you right. In usb.cpp:
double usbdevice::power_usage(struct result_bundle *result, struct
parameter_bundle *bundle)
{
        double power;
        double factor;
        double util;

        if (rootport || !cached_valid)
                return 0.0;


        power = 0;
        factor = get_parameter_value(index, bundle);
        util = get_result_value(r_index, result);

        power += util * factor / 100.0;

        return power;
}



but, if i understand it correctly, this values are not provided by usb.
If you start "powertop --calibrate" it will switch on/off some devices
and measure global power usage.

-- 
Regards,
Oleksij