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 Luis -- 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
