From 42639fcd443d97a9a471f4b8269620286dd7036b Mon Sep 17 00:00:00 2001 From: Bob Copeland Date: Mon, 30 Mar 2009 08:05:29 -0400 Subject: [PATCH] ath5k: reduce exported channel list Claiming every available 5 ghz channel has a couple of negative side-effects: scanning takes a long time, and the channel list overflows the available buffer space for netlink commands, resulting in: $ iw phy phy0 info command failed: No buffer space available (-105) This patch adds a modparam so people who want to see all the channels can do so by passing all_channels=1. By default users will see a smaller list of channels. This also halves scan time, from 10 seconds down to less than 5 when using world regulatory. Changes-licensed-under: 3-Clause-BSD Signed-off-by: Bob Copeland Reported-by: Simon Farnsworth Tested-By: Simon Farnsworth Signed-off-by: John W. Linville --- drivers/net/wireless/ath5k/base.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/drivers/net/wireless/ath5k/base.c b/drivers/net/wireless/ath5k/base.c index a08bc8a4fb6..d8c60c53d95 100644 --- a/drivers/net/wireless/ath5k/base.c +++ b/drivers/net/wireless/ath5k/base.c @@ -64,6 +64,10 @@ static int modparam_nohwcrypt; module_param_named(nohwcrypt, modparam_nohwcrypt, int, 0444); MODULE_PARM_DESC(nohwcrypt, "Disable hardware encryption."); +static int modparam_all_channels; +module_param_named(all_channels, modparam_all_channels, int, 0444); +MODULE_PARM_DESC(all_channels, "Expose all channels the device can use."); + /******************\ * Internal defines * @@ -862,6 +866,20 @@ ath5k_ieee2mhz(short chan) return 2212 + chan * 20; } +/* + * Returns true for the channel numbers used without all_channels modparam. + */ +static bool ath5k_is_standard_channel(short chan) +{ + return ((chan <= 14) || + /* UNII 1,2 */ + ((chan & 3) == 0 && chan >= 36 && chan <= 64) || + /* midband */ + ((chan & 3) == 0 && chan >= 100 && chan <= 140) || + /* UNII-3 */ + ((chan & 3) == 1 && chan >= 149 && chan <= 165)); +} + static unsigned int ath5k_copy_channels(struct ath5k_hw *ah, struct ieee80211_channel *channels, @@ -899,6 +917,9 @@ ath5k_copy_channels(struct ath5k_hw *ah, if (!ath5k_channel_ok(ah, freq, chfreq)) continue; + if (!modparam_all_channels && !ath5k_is_standard_channel(ch)) + continue; + /* Write channel info and increment counter */ channels[count].center_freq = freq; channels[count].band = (chfreq == CHANNEL_2GHZ) ? -- 2.39.3