On Fri, 2014-08-29 at 19:38 +0200, Steinar H. Gunderson wrote: > Linux already supports 802.11h, where the access point can tell the > client to reduce its transmission power. However, 802.11h is only > defined for 5 GHz, where the need for this is much smaller than on > 2.4 GHz. > > Cisco has their own solution, called DTPC (Dynamic Transmit Power > Control). Cisco APs on a controller sometimes but not always send > 802.11h; they always send DTPC, even on 2.4 GHz. This patch adds support > for parsing and honoring the DTPC IE in addition to the 802.11h > element (they do not always contain the same limits, so both must > be honored); the format is not documented, but very simple. The format is documented for CCX partners, I suppose, but we don't have access to that :) I think for some vendors shipping our stack this might become problematic. I think it would make sense to have a Kconfig option for this, probably hidden away under "if EXPERT" and defaulting to yes, to enable this code, it might be something that interferes with more CCX implementations maybe? > +static bool ieee80211_find_cisco_dtpc(struct ieee80211_sub_if_data > *sdata, The return value is useless here, so it could be void? > + if (pos[0] != 0x00 || pos[1] != 0x40 || > + pos[2] != 0x96 || pos[3] != 0x00) { > + break; > + } Please remove those useless braces - maybe run ./scripts/checkpatch.pl? johannes -- 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