ath9k: Add channel context structure

The channel context structure is defined to enable
multi-channel concurrency support.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/channel.c

@@ -0,0 +1,133 @@
+/*
+ * Copyright (c) 2014 Qualcomm Atheros, Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "ath9k.h"
+
+/* Set/change channels.  If the channel is really being changed, it's done
+ * by reseting the chip.  To accomplish this we must first cleanup any pending
+ * DMA, then restart stuff.
+ */
+static int ath_set_channel(struct ath_softc *sc)
+{
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath_common *common = ath9k_hw_common(ah);
+	struct ieee80211_hw *hw = sc->hw;
+	struct ath9k_channel *hchan;
+	struct cfg80211_chan_def *chandef = &sc->cur_chan->chandef;
+	struct ieee80211_channel *chan = chandef->chan;
+	int pos = chan->hw_value;
+	int old_pos = -1;
+	int r;
+
+	if (test_bit(ATH_OP_INVALID, &common->op_flags))
+		return -EIO;
+
+	if (ah->curchan)
+		old_pos = ah->curchan - &ah->channels[0];
+
+	ath_dbg(common, CONFIG, "Set channel: %d MHz width: %d\n",
+		chan->center_freq, chandef->width);
+
+	/* update survey stats for the old channel before switching */
+	spin_lock_bh(&common->cc_lock);
+	ath_update_survey_stats(sc);
+	spin_unlock_bh(&common->cc_lock);
+
+	ath9k_cmn_get_channel(hw, ah, chandef);
+
+	/* If the operating channel changes, change the survey in-use flags
+	 * along with it.
+	 * Reset the survey data for the new channel, unless we're switching
+	 * back to the operating channel from an off-channel operation.
+	 */
+	if (!sc->cur_chan->offchannel && sc->cur_survey != &sc->survey[pos]) {
+		if (sc->cur_survey)
+			sc->cur_survey->filled &= ~SURVEY_INFO_IN_USE;
+
+		sc->cur_survey = &sc->survey[pos];
+
+		memset(sc->cur_survey, 0, sizeof(struct survey_info));
+		sc->cur_survey->filled |= SURVEY_INFO_IN_USE;
+	} else if (!(sc->survey[pos].filled & SURVEY_INFO_IN_USE)) {
+		memset(&sc->survey[pos], 0, sizeof(struct survey_info));
+	}
+
+	hchan = &sc->sc_ah->channels[pos];
+	r = ath_reset_internal(sc, hchan);
+	if (r)
+		return r;
+
+	/* The most recent snapshot of channel->noisefloor for the old
+	 * channel is only available after the hardware reset. Copy it to
+	 * the survey stats now.
+	 */
+	if (old_pos >= 0)
+		ath_update_survey_nf(sc, old_pos);
+
+	/* Enable radar pulse detection if on a DFS channel. Spectral
+	 * scanning and radar detection can not be used concurrently.
+	 */
+	if (hw->conf.radar_enabled) {
+		u32 rxfilter;
+
+		/* set HW specific DFS configuration */
+		ath9k_hw_set_radar_params(ah);
+		rxfilter = ath9k_hw_getrxfilter(ah);
+		rxfilter |= ATH9K_RX_FILTER_PHYRADAR |
+				ATH9K_RX_FILTER_PHYERR;
+		ath9k_hw_setrxfilter(ah, rxfilter);
+		ath_dbg(common, DFS, "DFS enabled at freq %d\n",
+			chan->center_freq);
+	} else {
+		/* perform spectral scan if requested. */
+		if (test_bit(ATH_OP_SCANNING, &common->op_flags) &&
+			sc->spectral_mode == SPECTRAL_CHANSCAN)
+			ath9k_spectral_scan_trigger(hw);
+	}
+
+	return 0;
+}
+
+void ath_chanctx_init(struct ath_softc *sc)
+{
+	struct ath_chanctx *ctx;
+	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+	struct ieee80211_supported_band *sband;
+	struct ieee80211_channel *chan;
+	int i;
+
+	sband = &common->sbands[IEEE80211_BAND_2GHZ];
+	if (!sband->n_channels)
+		sband = &common->sbands[IEEE80211_BAND_5GHZ];
+
+	chan = &sband->channels[0];
+	for (i = 0; i < ATH9K_NUM_CHANCTX; i++) {
+		ctx = &sc->chanctx[i];
+		cfg80211_chandef_create(&ctx->chandef, chan, NL80211_CHAN_HT20);
+		INIT_LIST_HEAD(&ctx->vifs);
+	}
+	sc->cur_chan = &sc->chanctx[0];
+}
+
+int ath_chanctx_set_channel(struct ath_softc *sc, struct ath_chanctx *ctx,
+			      struct cfg80211_chan_def *chandef)
+{
+	memcpy(&ctx->chandef, chandef, sizeof(ctx->chandef));
+	if (ctx != sc->cur_chan)
+		return 0;
+
+	return ath_set_channel(sc);
+}