On 2010-11-11 8:22 PM, Luis R. Rodriguez wrote: > On Thu, Nov 11, 2010 at 11:15 AM, Mark Mentovai <mark@xxxxxxxxxxxx> wrote: >> In drivers/net/wireless/ath/ath9k/init.c, both CHAN2G and CHAN5G set >> .max_power to 20, represented in dBm. Iâm wondering how this number >> was chosen. Is it simply a safe generic value? Iâm dealing with a >> device on which the vendorâs madwifi-based binary driver would show >> 23dBm for 2.4GHz and 18dBm for 5GHz (although only when I asked it for >> 26dBm and 24dBm respectively, so Iâm not sure which set of numbers to >> believe.) >> >> I noticed that in ath9k, if these .max_power limits are raised, the >> driver is happy to set a somewhat higher transmit power. In this case, >> it will max out at 25dBm for 2.4GHz and 21dBm for 5GHz. These are >> still below the relevant regulatory limits. These values seem to be >> computed by routines in eeprom_*.c, so Iâm wondering if theyâre based >> on the cardâs own data and safe to use without fear of burning the >> radios. > > The values are just some safe value to use as defaults but will > quickly be replaced by the max regulatory allowed and then upon > further inspection also capped to the lower value of the regulatory > limit, the max allowed device limit (where things start becoming > unreliable), and the CTL indexed limit which is calibrated > specifically for the card you use, so this will vary. You can read > more about it here: > > http://wireless.kernel.org/en/users/Drivers/ath That should have already been taken care of by this commit (w-t): commit 6cdd07721180145b7ef46bd63f1eee636983f0e6 Author: Felix Fietkau <nbd@xxxxxxxxxxx> Date: Wed Oct 20 02:09:46 2010 +0200 ath9k: initialize per-channel tx power limits instead of hardcoding them - Felix -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
