8 files changed, 425 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath9k/Kconfig b/drivers/net/wireless/ath/ath9k/Kconfig
index 7b4c074e12fa..1b4786ae00ac 100644
--- a/drivers/net/wireless/ath/ath9k/Kconfig
+++ b/drivers/net/wireless/ath/ath9k/Kconfig
@@ -2,6 +2,9 @@ config ATH9K_HW
         tristate
 config ATH9K_COMMON
         tristate
+config ATH9K_DFS_DEBUGFS
+        def_bool y
+        depends on ATH9K_DEBUGFS && ATH9K_DFS_CERTIFIED
 
 config ATH9K
         tristate "Atheros 802.11n wireless cards support"
@@ -51,6 +54,25 @@ config ATH9K_DEBUGFS
 
           Also required for changing debug message flags at run time.
 
+config ATH9K_DFS_CERTIFIED
+        bool "Atheros DFS support for certified platforms"
+        depends on ATH9K && EXPERT
+        default n
+        ---help---
+          This option enables DFS support for initiating radiation on
+          ath9k. There is no way to dynamically detect if a card was DFS
+          certified and as such this is left as a build time option. This
+          option should only be enabled by system integrators that can
+          guarantee that all the platforms that their kernel will run on
+          have obtained appropriate regulatory body certification for a
+          respective Atheros card by using ath9k on the target shipping
+          platforms.
+
+          This is currently only a placeholder for future DFS support,
+          as DFS support requires more components that still need to be
+          developed. At this point enabling this option won't do anything
+          except increase code size.
+
 config ATH9K_RATE_CONTROL
         bool "Atheros ath9k rate control"
         depends on ATH9K
diff --git a/drivers/net/wireless/ath/ath9k/Makefile b/drivers/net/wireless/ath/ath9k/Makefile
index 390797db5273..da02242499af 100644
--- a/drivers/net/wireless/ath/ath9k/Makefile
+++ b/drivers/net/wireless/ath/ath9k/Makefile
@@ -10,6 +10,8 @@ ath9k-$(CONFIG_ATH9K_RATE_CONTROL) += rc.o
 ath9k-$(CONFIG_ATH9K_PCI) += pci.o
 ath9k-$(CONFIG_ATH9K_AHB) += ahb.o
 ath9k-$(CONFIG_ATH9K_DEBUGFS) += debug.o
+ath9k-$(CONFIG_ATH9K_DFS_DEBUGFS) += dfs_debug.o
+ath9k-$(CONFIG_ATH9K_DFS_CERTIFIED) += dfs.o
 
 obj-$(CONFIG_ATH9K) += ath9k.o
 
diff --git a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
index 5cb8cceffd0b..68d972bf232d 100644
--- a/drivers/net/wireless/ath/ath9k/debug.c
+++ b/drivers/net/wireless/ath/ath9k/debug.c
@@ -1630,6 +1630,9 @@ int ath9k_init_debug(struct ath_hw *ah)
         debugfs_create_file("debug", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
                             sc, &fops_debug);
 #endif
+
+        ath9k_dfs_init_debug(sc);
+
         debugfs_create_file("dma", S_IRUSR, sc->debug.debugfs_phy, sc,
                             &fops_dma);
         debugfs_create_file("interrupt", S_IRUSR, sc->debug.debugfs_phy, sc,
diff --git a/drivers/net/wireless/ath/ath9k/debug.h b/drivers/net/wireless/ath/ath9k/debug.h
index 356352ac2d6e..776a24ada600 100644
--- a/drivers/net/wireless/ath/ath9k/debug.h
+++ b/drivers/net/wireless/ath/ath9k/debug.h
@@ -19,6 +19,7 @@
 
 #include "hw.h"
 #include "rc.h"
+#include "dfs_debug.h"
 
 struct ath_txq;
 struct ath_buf;
@@ -187,6 +188,7 @@ struct ath_stats {
         struct ath_interrupt_stats istats;
         struct ath_tx_stats txstats[ATH9K_NUM_TX_QUEUES];
         struct ath_rx_stats rxstats;
+        struct ath_dfs_stats dfs_stats;
         u32 reset[__RESET_TYPE_MAX];
 };
 
diff --git a/drivers/net/wireless/ath/ath9k/dfs.c b/drivers/net/wireless/ath/ath9k/dfs.c
new file mode 100644
index 000000000000..e4e84a9e6273
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/dfs.c
@@ -0,0 +1,215 @@
+/*
+ * Copyright (c) 2008-2011 Atheros Communications Inc.
+ * Copyright (c) 2011 Neratec Solutions AG
+ *
+ * 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 "hw.h"
+#include "hw-ops.h"
+#include "ath9k.h"
+#include "dfs.h"
+#include "dfs_debug.h"
+
+/*
+ * TODO: move into or synchronize this with generic header
+ *       as soon as IF is defined
+ */
+struct dfs_radar_pulse {
+        u16 freq;
+        u64 ts;
+        u32 width;
+        u8 rssi;
+};
+
+/* internal struct to pass radar data */
+struct ath_radar_data {
+        u8 pulse_bw_info;
+        u8 rssi;
+        u8 ext_rssi;
+        u8 pulse_length_ext;
+        u8 pulse_length_pri;
+};
+
+/* convert pulse duration to usecs, considering clock mode */
+static u32 dur_to_usecs(struct ath_hw *ah, u32 dur)
+{
+        const u32 AR93X_NSECS_PER_DUR = 800;
+        const u32 AR93X_NSECS_PER_DUR_FAST = (8000 / 11);
+        u32 nsecs;
+
+        if (IS_CHAN_A_FAST_CLOCK(ah, ah->curchan))
+                nsecs = dur * AR93X_NSECS_PER_DUR_FAST;
+        else
+                nsecs = dur * AR93X_NSECS_PER_DUR;
+
+        return (nsecs + 500) / 1000;
+}
+
+#define PRI_CH_RADAR_FOUND 0x01
+#define EXT_CH_RADAR_FOUND 0x02
+static bool
+ath9k_postprocess_radar_event(struct ath_softc *sc,
+                              struct ath_radar_data *are,
+                              struct dfs_radar_pulse *drp)
+{
+        u8 rssi;
+        u16 dur;
+
+        ath_dbg(ath9k_hw_common(sc->sc_ah), ATH_DBG_DFS,
+                "pulse_bw_info=0x%x, pri,ext len/rssi=(%u/%u, %u/%u)\n",
+                are->pulse_bw_info,
+                are->pulse_length_pri, are->rssi,
+                are->pulse_length_ext, are->ext_rssi);
+
+        /*
+         * Only the last 2 bits of the BW info are relevant, they indicate
+         * which channel the radar was detected in.
+         */
+        are->pulse_bw_info &= 0x03;
+
+        switch (are->pulse_bw_info) {
+        case PRI_CH_RADAR_FOUND:
+                /* radar in ctrl channel */
+                dur = are->pulse_length_pri;
+                DFS_STAT_INC(sc, pri_phy_errors);
+                /*
+                 * cannot use ctrl channel RSSI
+                 * if extension channel is stronger
+                 */
+                rssi = (are->ext_rssi >= (are->rssi + 3)) ? 0 : are->rssi;
+                break;
+        case EXT_CH_RADAR_FOUND:
+                /* radar in extension channel */
+                dur = are->pulse_length_ext;
+                DFS_STAT_INC(sc, ext_phy_errors);
+                /*
+                 * cannot use extension channel RSSI
+                 * if control channel is stronger
+                 */
+                rssi = (are->rssi >= (are->ext_rssi + 12)) ? 0 : are->ext_rssi;
+                break;
+        case (PRI_CH_RADAR_FOUND | EXT_CH_RADAR_FOUND):
+                /*
+                 * Conducted testing, when pulse is on DC, both pri and ext
+                 * durations are reported to be same
+                 *
+                 * Radiated testing, when pulse is on DC, different pri and
+                 * ext durations are reported, so take the larger of the two
+                 */
+                if (are->pulse_length_ext >= are->pulse_length_pri)
+                        dur = are->pulse_length_ext;
+                else
+                        dur = are->pulse_length_pri;
+                DFS_STAT_INC(sc, dc_phy_errors);
+
+                /* when both are present use stronger one */
+                rssi = (are->rssi < are->ext_rssi) ? are->ext_rssi : are->rssi;
+                break;
+        default:
+                /*
+                 * Bogus bandwidth info was received in descriptor,
+                 * so ignore this PHY error
+                 */
+                DFS_STAT_INC(sc, bwinfo_discards);
+                return false;
+        }
+
+        if (rssi == 0) {
+                DFS_STAT_INC(sc, rssi_discards);
+                return false;
+        }
+
+        /*
+         * TODO: check chirping pulses
+         *       checks for chirping are dependent on the DFS regulatory domain
+         *       used, which is yet TBD
+         */
+
+        /* convert duration to usecs */
+        drp->width = dur_to_usecs(sc->sc_ah, dur);
+        drp->rssi = rssi;
+
+        DFS_STAT_INC(sc, pulses_detected);
+        return true;
+}
+#undef PRI_CH_RADAR_FOUND
+#undef EXT_CH_RADAR_FOUND
+
+/*
+ * DFS: check PHY-error for radar pulse and feed the detector
+ */
+void ath9k_dfs_process_phyerr(struct ath_softc *sc, void *data,
+                              struct ath_rx_status *rs, u64 mactime)
+{
+        struct ath_radar_data ard;
+        u16 datalen;
+        char *vdata_end;
+        struct dfs_radar_pulse drp;
+        struct ath_hw *ah = sc->sc_ah;
+        struct ath_common *common = ath9k_hw_common(ah);
+
+        if ((!(rs->rs_phyerr != ATH9K_PHYERR_RADAR)) &&
+            (!(rs->rs_phyerr != ATH9K_PHYERR_FALSE_RADAR_EXT))) {
+                ath_dbg(common, ATH_DBG_DFS,
+                        "Error: rs_phyer=0x%x not a radar error\n",
+                        rs->rs_phyerr);
+                return;
+        }
+
+        datalen = rs->rs_datalen;
+        if (datalen == 0) {
+                DFS_STAT_INC(sc, datalen_discards);
+                return;
+        }
+
+        ard.rssi = rs->rs_rssi_ctl0;
+        ard.ext_rssi = rs->rs_rssi_ext0;
+
+        /*
+         * hardware stores this as 8 bit signed value.
+         * we will cap it at 0 if it is a negative number
+         */
+        if (ard.rssi & 0x80)
+                ard.rssi = 0;
+        if (ard.ext_rssi & 0x80)
+                ard.ext_rssi = 0;
+
+        vdata_end = (char *)data + datalen;
+        ard.pulse_bw_info = vdata_end[-1];
+        ard.pulse_length_ext = vdata_end[-2];
+        ard.pulse_length_pri = vdata_end[-3];
+
+        ath_dbg(common, ATH_DBG_DFS,
+                "bw_info=%d, length_pri=%d, length_ext=%d, "
+                "rssi_pri=%d, rssi_ext=%d\n",
+                ard.pulse_bw_info, ard.pulse_length_pri, ard.pulse_length_ext,
+                ard.rssi, ard.ext_rssi);
+
+        drp.freq = ah->curchan->channel;
+        drp.ts = mactime;
+        if (ath9k_postprocess_radar_event(sc, &ard, &drp)) {
+                static u64 last_ts;
+                ath_dbg(common, ATH_DBG_DFS,
+                        "ath9k_dfs_process_phyerr: channel=%d, ts=%llu, "
+                        "width=%d, rssi=%d, delta_ts=%llu\n",
+                        drp.freq, drp.ts, drp.width, drp.rssi, drp.ts-last_ts);
+                last_ts = drp.ts;
+                /*
+                 * TODO: forward pulse to pattern detector
+                 *
+                 * ieee80211_add_radar_pulse(drp.freq, drp.ts,
+                 *                           drp.width, drp.rssi);
+                 */
+        }
+}
diff --git a/drivers/net/wireless/ath/ath9k/dfs.h b/drivers/net/wireless/ath/ath9k/dfs.h
new file mode 100644
index 000000000000..c2412857f122
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/dfs.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2008-2011 Atheros Communications Inc.
+ * Copyright (c) 2011 Neratec Solutions AG
+ *
+ * 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.
+ */
+
+#ifndef ATH9K_DFS_H
+#define ATH9K_DFS_H
+
+#if defined(CONFIG_ATH9K_DFS_CERTIFIED)
+/**
+ * ath9k_dfs_process_phyerr - process radar PHY error
+ * @sc: ath_softc
+ * @data: RX payload data
+ * @rs: RX status after processing descriptor
+ * @mactime: receive time
+ *
+ * This function is called whenever the HW DFS module detects a radar
+ * pulse and reports it as a PHY error.
+ *
+ * The radar information provided as raw payload data is validated and
+ * filtered for false pulses. Events passing all tests are forwarded to
+ * the upper layer for pattern detection.
+ */
+void ath9k_dfs_process_phyerr(struct ath_softc *sc, void *data,
+                              struct ath_rx_status *rs, u64 mactime);
+#else
+static inline void ath9k_dfs_process_phyerr(struct ath_softc *sc, void *data,
+                                            struct ath_rx_status *rs, u64 mactime) { }
+#endif
+
+#endif /* ATH9K_DFS_H */
diff --git a/drivers/net/wireless/ath/ath9k/dfs_debug.c b/drivers/net/wireless/ath/ath9k/dfs_debug.c
new file mode 100644
index 000000000000..106d031d834a
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/dfs_debug.c
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2008-2011 Atheros Communications Inc.
+ * Copyright (c) 2011 Neratec Solutions AG
+ *
+ * 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 <linux/debugfs.h>
+#include <linux/export.h>
+
+#include "ath9k.h"
+#include "dfs_debug.h"
+
+#define ATH9K_DFS_STAT(s, p) \
+        len += snprintf(buf + len, size - len, "%28s : %10u\n", s, \
+                        sc->debug.stats.dfs_stats.p);
+
+static ssize_t read_file_dfs(struct file *file, char __user *user_buf,
+                             size_t count, loff_t *ppos)
+{
+        struct ath_softc *sc = file->private_data;
+        struct ath9k_hw_version *hw_ver = &sc->sc_ah->hw_version;
+        char *buf;
+        unsigned int len = 0, size = 8000;
+        ssize_t retval = 0;
+
+        buf = kzalloc(size, GFP_KERNEL);
+        if (buf == NULL)
+                return -ENOMEM;
+
+        len += snprintf(buf + len, size - len, "DFS support for "
+                        "macVersion = 0x%x, macRev = 0x%x: %s\n",
+                        hw_ver->macVersion, hw_ver->macRev,
+                        (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_DFS) ?
+                                        "enabled" : "disabled");
+        ATH9K_DFS_STAT("DFS pulses detected     ", pulses_detected);
+        ATH9K_DFS_STAT("Datalen discards        ", datalen_discards);
+        ATH9K_DFS_STAT("RSSI discards           ", rssi_discards);
+        ATH9K_DFS_STAT("BW info discards        ", bwinfo_discards);
+        ATH9K_DFS_STAT("Primary channel pulses  ", pri_phy_errors);
+        ATH9K_DFS_STAT("Secondary channel pulses", ext_phy_errors);
+        ATH9K_DFS_STAT("Dual channel pulses     ", dc_phy_errors);
+
+        if (len > size)
+                len = size;
+
+        retval = simple_read_from_buffer(user_buf, count, ppos, buf, len);
+        kfree(buf);
+
+        return retval;
+}
+
+static int ath9k_dfs_debugfs_open(struct inode *inode, struct file *file)
+{
+        file->private_data = inode->i_private;
+
+        return 0;
+}
+
+static const struct file_operations fops_dfs_stats = {
+        .read = read_file_dfs,
+        .open = ath9k_dfs_debugfs_open,
+        .owner = THIS_MODULE,
+        .llseek = default_llseek,
+};
+
+void ath9k_dfs_init_debug(struct ath_softc *sc)
+{
+        debugfs_create_file("dfs_stats", S_IRUSR,
+                            sc->debug.debugfs_phy, sc, &fops_dfs_stats);
+}
diff --git a/drivers/net/wireless/ath/ath9k/dfs_debug.h b/drivers/net/wireless/ath/ath9k/dfs_debug.h
new file mode 100644
index 000000000000..6e1e2a71659e
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/dfs_debug.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2008-2011 Atheros Communications Inc.
+ * Copyright (c) 2011 Neratec Solutions AG
+ *
+ * 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.
+ */
+
+
+#ifndef DFS_DEBUG_H
+#define DFS_DEBUG_H
+
+#include "hw.h"
+
+/**
+ * struct ath_dfs_stats - DFS Statistics
+ *
+ * @pulses_detected:  No. of pulses detected so far
+ * @datalen_discards: No. of pulses discarded due to invalid datalen
+ * @rssi_discards:    No. of pulses discarded due to invalid RSSI
+ * @bwinfo_discards:  No. of pulses discarded due to invalid BW info
+ * @pri_phy_errors:   No. of pulses reported for primary channel
+ * @ext_phy_errors:   No. of pulses reported for extension channel
+ * @dc_phy_errors:    No. of pulses reported for primary + extension channel
+ */
+struct ath_dfs_stats {
+        u32 pulses_detected;
+        u32 datalen_discards;
+        u32 rssi_discards;
+        u32 bwinfo_discards;
+        u32 pri_phy_errors;
+        u32 ext_phy_errors;
+        u32 dc_phy_errors;
+};
+
+#if defined(CONFIG_ATH9K_DFS_DEBUGFS)
+
+#define DFS_STAT_INC(sc, c) (sc->debug.stats.dfs_stats.c++)
+void ath9k_dfs_init_debug(struct ath_softc *sc);
+
+#else
+
+#define DFS_STAT_INC(sc, c) do { } while (0)
+static inline void ath9k_dfs_init_debug(struct ath_softc *sc) { }
+
+#endif /* CONFIG_ATH9K_DFS_DEBUGFS */
+
+#endif /* DFS_DEBUG_H */