ath9k: add DFS radar pulse processing

This initial DFS module provides basic functionality to deal
with radar pulses reported by the Atheros DFS HW pulse detector.

The reported data is evaluated and basic plausibility checks
are performed to filter false pulses. Passing radar pulses are
forwarded to pattern detectors which are not yet implemented.

(Some modifications to actually use ATH9K_DFS_DEBUGFS based on comments
from Julian Calaby <julian.calaby@gmail.com>. -- JWL)

Signed-off-by: Zefir Kurtisi <zefir.kurtisi@neratec.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 81 insertions, 0 deletions

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);
+}