On 2010-07-28 10:52 PM, Luis R. Rodriguez wrote: > On Wed, Jul 28, 2010 at 10:45 AM, Felix Fietkau <nbd@xxxxxxxxxxx> wrote: >> The noise floor history buffer is currently not kept per channel, which >> can lead to problems when changing channels from a clean channel to a >> noisy one. Also when switching from HT20 to HT40, the noise floor >> history buffer is full of measurements, but none of them contain data >> for the extension channel, which it needs quite a bit of time to recover >> from. >> >> This patch puts all the per-channel calibration data into a single data >> structure, and gives the the driver control over whether that is used >> per-channel or even not used for some channels. >> >> For ath9k_htc, I decided to keep this per-channel in order to avoid >> creating regressions. >> >> For ath9k, the data is kept only for the operating channel, which saves >> some space. ath9k_hw takes care of wiping old data when the operating >> channel or its channel flags change. >> >> Signed-off-by: Felix Fietkau <nbd@xxxxxxxxxxx> > > But this also means every time we want to get operational on a channel > we have to learn the current noise all over again. This means for WiFi > Direct every channel swap we'd have to learn to walk, which happens > quite often. What do you think? Sorry, I know we discussed this > approach and I seemed fine but this just occurred to me now, and will > become really important later when we support WiFi Direct. When we get to implementing per-vif channel settings with switching being done in mac80211, we can just move the calibration data to ath9k's virtual interface data and thus keep the calibration for multiple operating channels. - 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
