On Mon, Dec 22, 2014 at 04:07:34PM +0100, Pali Rohár wrote: > On Sunday 21 December 2014 20:51:14 Guenter Roeck wrote: > > On 12/21/2014 09:23 AM, Pali Rohár wrote: > > > This patch adds new function i8k_get_fan_nominal_speed() for > > > doing SMM call which will return nominal fan RPM for > > > specified fan speed. It returns nominal RPM value at which > > > fan operate when speed (0, 1, 2, 3) is set. It looks like > > > RPM value is not accurate, but still provides very useful > > > information. > > > > > > First it can be used to validate if certain fan speed could > > > be accepted by SMM for setting fan speed and we can use > > > this routine to detect maximal fan speed. > > > > > > Second it returns RPM value, so we can check if value looks > > > correct with multiplier 30 or multiplier 1 (until now only > > > these two multiplier were used). If RPM value with > > > multiplier 30 is too high, then multiplier 1 is used. > > > > > > In case when SMM reports that new function is not supported > > > we will fallback to old hardcoded values. Maximal fan speed > > > would be 2 and RPM multiplier 30. > > > > > > Signed-off-by: Pali Rohár <[email protected]> > > > Tested-by: Pali Rohár <[email protected]> > > > > Auto-detection of both multiplier and maximum speed tested > > working on M140 (after removing its configuration entry). > > > > On Studio 1555, multiplier auto-detection works, but fan_max > > auto-detection fails. A speed value of '3' is accepted, but > > it does not set the fan speed to its maximum. Also, after > > setting the speed value to '3', reading it back returns to > > old value. No idea what it does or is expected to do. Reading > > the nominal speed does return a valid value. > > > > Given that, I think we should not try to auto-detect fan_max, > > but keep the current code (meaning either use 2 or 3 > > depending on the configuration data, with 2 as default if > > nothing else is known). > > > > Thanks, > > Guenter > > Ok. In this case I will remove max fan speed detection code and > we will use config data for those some machines which support > TURBO speed. If multiplier detection on Studio is working fine, I > can send another patch which remove config data for Studio > (because default multiplier is 2). > > Can you check which nominal value Studio returns for speed 3? > Maybe it is some special? > It was a bit higher than the value returned for speed 2. Nothing special as far as I could see, only that setting a value of 3 did not modify the fan speed.
Note that I won't be able to test further in the next two weeks; I am about 6,000 miles away from my Dell laptops right now. Guenter -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
