[ath9k-devel] [PATCH 3/3] Adding spectral scan functionality to ath9k_htc driver. Tested using a AR9271 WiFi card.

[Ashish Patro <patro@cs.wisc.edu>]

---
 drivers/net/wireless/ath/ath9k/Makefile           |    2 +-
 drivers/net/wireless/ath/ath9k/ar9002_phy.c       |   10 +-
 drivers/net/wireless/ath/ath9k/htc.h              |   13 +
 drivers/net/wireless/ath/ath9k/htc_drv_debug.c    |    5 +-
 drivers/net/wireless/ath/ath9k/htc_drv_init.c     |    8 +
 drivers/net/wireless/ath/ath9k/htc_drv_main.c     |   81 +++++
 drivers/net/wireless/ath/ath9k/htc_drv_spectral.c |  358 +++++++++++++++++++++
 drivers/net/wireless/ath/ath9k/htc_drv_txrx.c     |   17 +
 8 files changed, 490 insertions(+), 4 deletions(-)
 create mode 100644 drivers/net/wireless/ath/ath9k/htc_drv_spectral.c

diff --git a/drivers/net/wireless/ath/ath9k/Makefile b/drivers/net/wireless/ath/ath9k/Makefile
index 613bf30..aaa5a34 100644
--- a/drivers/net/wireless/ath/ath9k/Makefile
+++ b/drivers/net/wireless/ath/ath9k/Makefile
@@ -65,6 +65,6 @@ ath9k_htc-y +=	htc_hst.o \
 		htc_drv_init.o \
 		htc_drv_gpio.o
 
-ath9k_htc-$(CONFIG_ATH9K_HTC_DEBUGFS) += htc_drv_debug.o
+ath9k_htc-$(CONFIG_ATH9K_HTC_DEBUGFS) += htc_drv_debug.o htc_drv_spectral.o
 
 obj-$(CONFIG_ATH9K_HTC) += ath9k_htc.o
diff --git a/drivers/net/wireless/ath/ath9k/ar9002_phy.c b/drivers/net/wireless/ath/ath9k/ar9002_phy.c
index 9a2afa2..e9eb794 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9002_phy.c
@@ -641,11 +641,17 @@ static void ar9002_hw_spectral_scan_config(struct ath_hw *ah,
 	/* on AR92xx, the highest bit of count will make the the chip send
 	 * spectral samples endlessly. Check if this really was intended,
 	 * and fix otherwise.
+   *
+   * For AR9271 chipsets, set count = 0 using the debugfs mechanism.
 	 */
 	count = param->count;
-	if (param->endless)
+	if (param->endless) {
 		count = 0x80;
-	else if (count & 0x80)
+
+    if (AR_SREV_9271(ah)) {
+      count = 0;
+    }
+	} else if (count & 0x80)
 		count = 0x7f;
 
 	REG_RMW_FIELD(ah, AR_PHY_SPECTRAL_SCAN,
diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
index dab1f0c..178eb99 100644
--- a/drivers/net/wireless/ath/ath9k/htc.h
+++ b/drivers/net/wireless/ath/ath9k/htc.h
@@ -31,6 +31,7 @@
 #include "htc_hst.h"
 #include "hif_usb.h"
 #include "wmi.h"
+#include "spectral.h"
 
 #define ATH_STA_SHORT_CALINTERVAL 1000    /* 1 second */
 #define ATH_AP_SHORT_CALINTERVAL  100     /* 100 ms */
@@ -529,6 +530,11 @@ struct ath9k_htc_priv {
 	struct ath9k_debug debug;
 #endif
 	struct mutex mutex;
+
+	/* relay(fs) channel for spectral scan */
+	struct rchan *rfs_chan_spec_scan;
+	enum spectral_mode spectral_mode;
+	struct ath_spec_scan spec_config;
 };
 
 static inline void ath_read_cachesize(struct ath_common *common, int *csz)
@@ -636,4 +642,11 @@ int ath9k_htc_init_debug(struct ath_hw *ah);
 static inline int ath9k_htc_init_debug(struct ath_hw *ah) { return 0; };
 #endif /* CONFIG_ATH9K_HTC_DEBUGFS */
 
+void ath9k_htc_spectral_init_debug(struct ath9k_htc_priv *priv);
+void ath9k_htc_spectral_deinit_debug(struct ath9k_htc_priv *priv);
+
+void ath9k_htc_spectral_scan_trigger(struct ieee80211_hw *hw);
+int ath9k_htc_spectral_scan_config(struct ieee80211_hw *hw,
+			       enum spectral_mode spectral_mode);
+
 #endif /* HTC_H */
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_debug.c b/drivers/net/wireless/ath/ath9k/htc_drv_debug.c
index fb071ee..00d8905 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_debug.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_debug.c
@@ -992,7 +992,10 @@ int ath9k_htc_init_debug(struct ath_hw *ah)
 					     priv->hw->wiphy->debugfsdir);
 	if (!priv->debug.debugfs_phy)
 		return -ENOMEM;
-
+  
+  /* Initialize the debugFS files for the spectral scans */
+	ath9k_htc_spectral_init_debug(priv);
+ 
 	debugfs_create_file("tgt_int_stats", S_IRUSR, priv->debug.debugfs_phy,
 			    priv, &fops_tgt_int_stats);
 	debugfs_create_file("tgt_tx_stats", S_IRUSR, priv->debug.debugfs_phy,
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_init.c b/drivers/net/wireless/ath/ath9k/htc_drv_init.c
index 8a3bd5f..71a80ba 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_init.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_init.c
@@ -449,6 +449,14 @@ static void ath9k_init_misc(struct ath9k_htc_priv *priv)
 
 	common->last_rssi = ATH_RSSI_DUMMY_MARKER;
 	priv->ah->opmode = NL80211_IFTYPE_STATION;
+
+	priv->spec_config.enabled = 0;
+  /* Set false for AR9271. */
+	priv->spec_config.short_repeat = false;
+	priv->spec_config.count = 8;
+	priv->spec_config.endless = false;
+	priv->spec_config.period = 18;
+	priv->spec_config.fft_period = 0x02;
 }
 
 static int ath9k_init_priv(struct ath9k_htc_priv *priv,
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_main.c b/drivers/net/wireless/ath/ath9k/htc_drv_main.c
index f46cd02..051ffa7 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_main.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_main.c
@@ -310,6 +310,11 @@ static int ath9k_htc_set_channel(struct ath9k_htc_priv *priv,
 
 	mod_timer(&priv->tx.cleanup_timer,
 		  jiffies + msecs_to_jiffies(ATH9K_HTC_TX_CLEANUP_INTERVAL));
+	
+  /* perform spectral scan if requested. */
+  if (test_bit(ATH_OP_SCANNING, &priv->op_flags) &&
+    priv->spectral_mode == SPECTRAL_CHANSCAN)
+    ath9k_htc_spectral_scan_trigger(hw);
 
 err:
 	ath9k_htc_ps_restore(priv);
@@ -1158,6 +1163,82 @@ static void ath9k_htc_remove_interface(struct ieee80211_hw *hw,
 	mutex_unlock(&priv->mutex);
 }
 
+/* Start generating the spectral scans. */
+void ath9k_htc_spectral_scan_trigger(struct ieee80211_hw *hw)
+{
+	struct ath9k_htc_priv *priv = hw->priv;
+	struct ath_hw *ah = priv->ah;
+	struct ath_common *common = ath9k_hw_common(ah);
+	u32 rxfilter;
+  
+  /* TODO: Is this condition required?
+	if (config_enabled(CONFIG_ATH9K_TX99))
+		return;
+  */
+
+	if (!ath9k_hw_ops(ah)->spectral_scan_trigger) {
+		ath_err(common, "spectrum analyzer not implemented on this hardware\n");
+		return;
+	}
+
+	ath9k_htc_ps_wakeup(priv);
+	rxfilter = ath9k_hw_getrxfilter(ah);
+	ath9k_hw_setrxfilter(ah, rxfilter |
+				 ATH9K_RX_FILTER_PHYRADAR |
+				 ATH9K_RX_FILTER_PHYERR);
+
+	/* TODO: usually this should not be neccesary, but for some reason
+	 * (or in some mode?) the trigger must be called after the
+	 * configuration, otherwise the register will have its values reset
+	 * (on my ar9220 to value 0x01002310)
+	 */
+	ath9k_htc_spectral_scan_config(hw, priv->spectral_mode);
+	ath9k_hw_ops(ah)->spectral_scan_trigger(ah);
+	ath9k_htc_ps_restore(priv);
+}
+
+/* Configure the status of the spectral scan feature. */
+int ath9k_htc_spectral_scan_config(struct ieee80211_hw *hw,
+			       enum spectral_mode spectral_mode)
+{
+	struct ath9k_htc_priv *priv = hw->priv;
+	struct ath_hw *ah = priv->ah;
+	struct ath_common *common = ath9k_hw_common(ah);
+ 
+	if (!ath9k_hw_ops(ah)->spectral_scan_trigger) {
+		ath_err(common, "spectrum analyzer not implemented on this hardware\n");
+		return -1;
+	}
+
+	switch (spectral_mode) {
+	case SPECTRAL_DISABLED:
+		priv->spec_config.enabled = 0;
+		break;
+	case SPECTRAL_BACKGROUND:
+		/* send endless samples.
+		 */
+		priv->spec_config.endless = 1;
+		priv->spec_config.enabled = 1;
+		break;
+	case SPECTRAL_CHANSCAN:
+	case SPECTRAL_MANUAL:
+		priv->spec_config.endless = 0;
+		priv->spec_config.enabled = 1;
+		break;
+	default:
+		return -1;
+	}
+
+	ath9k_htc_ps_wakeup(priv);
+	ath9k_hw_ops(ah)->spectral_scan_config(ah, &priv->spec_config);
+	ath9k_htc_ps_restore(priv);
+
+	priv->spectral_mode = spectral_mode;
+
+	return 0;
+}
+
+ 
 static int ath9k_htc_config(struct ieee80211_hw *hw, u32 changed)
 {
 	struct ath9k_htc_priv *priv = hw->priv;
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_spectral.c b/drivers/net/wireless/ath/ath9k/htc_drv_spectral.c
new file mode 100644
index 0000000..d6a0894
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_spectral.c
@@ -0,0 +1,358 @@
+/*
+ * Copyright (c) 2013 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 <linux/relay.h>
+#include "htc.h"
+
+/*********************/
+/* spectral_scan_ctl */
+/*********************/
+
+static ssize_t read_file_spec_scan_ctl(struct file *file, char __user *user_buf,
+				       size_t count, loff_t *ppos)
+{
+	struct ath9k_htc_priv *priv = file->private_data;
+	char *mode = "";
+	unsigned int len;
+
+	switch (priv->spectral_mode) {
+	case SPECTRAL_DISABLED:
+		mode = "disable";
+		break;
+	case SPECTRAL_BACKGROUND:
+		mode = "background";
+		break;
+	case SPECTRAL_CHANSCAN:
+		mode = "chanscan";
+		break;
+	case SPECTRAL_MANUAL:
+		mode = "manual";
+		break;
+	}
+	len = strlen(mode);
+	return simple_read_from_buffer(user_buf, count, ppos, mode, len);
+}
+
+static ssize_t write_file_spec_scan_ctl(struct file *file,
+					const char __user *user_buf,
+					size_t count, loff_t *ppos)
+{
+	struct ath9k_htc_priv *priv = file->private_data;
+	struct ath_common *common = ath9k_hw_common(priv->ah);
+	char buf[32];
+	ssize_t len;
+
+  /* TODO: Is it required for ath9k_htc??
+	if (config_enabled(CONFIG_ATH9K_TX99))
+		return -EOPNOTSUPP;
+  */
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+
+	if (strncmp("trigger", buf, 7) == 0) {
+		ath9k_htc_spectral_scan_trigger(priv->hw);
+	} else if (strncmp("background", buf, 9) == 0) {
+		ath9k_htc_spectral_scan_config(priv->hw, SPECTRAL_BACKGROUND);
+		ath_dbg(common, CONFIG, "spectral scan: background mode enabled\n");
+	} else if (strncmp("chanscan", buf, 8) == 0) {
+		ath9k_htc_spectral_scan_config(priv->hw, SPECTRAL_CHANSCAN);
+		ath_dbg(common, CONFIG, "spectral scan: channel scan mode enabled\n");
+	} else if (strncmp("manual", buf, 6) == 0) {
+		ath9k_htc_spectral_scan_config(priv->hw, SPECTRAL_MANUAL);
+		ath_dbg(common, CONFIG, "spectral scan: manual mode enabled\n");
+	} else if (strncmp("disable", buf, 7) == 0) {
+		ath9k_htc_spectral_scan_config(priv->hw, SPECTRAL_DISABLED);
+		ath_dbg(common, CONFIG, "spectral scan: disabled\n");
+	} else {
+		return -EINVAL;
+	}
+
+	return count;
+}
+
+static const struct file_operations fops_spec_scan_ctl = {
+	.read = read_file_spec_scan_ctl,
+	.write = write_file_spec_scan_ctl,
+	.open = simple_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+/*************************/
+/* spectral_short_repeat */
+/*************************/
+
+static ssize_t read_file_spectral_short_repeat(struct file *file,
+					       char __user *user_buf,
+					       size_t count, loff_t *ppos)
+{
+	struct ath9k_htc_priv *priv = file->private_data;
+	char buf[32];
+	unsigned int len;
+
+	len = sprintf(buf, "%d\n", priv->spec_config.short_repeat);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_spectral_short_repeat(struct file *file,
+						const char __user *user_buf,
+						size_t count, loff_t *ppos)
+{
+	struct ath9k_htc_priv *priv = file->private_data;
+	unsigned long val;
+	char buf[32];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (kstrtoul(buf, 0, &val))
+		return -EINVAL;
+
+	if (val < 0 || val > 1)
+		return -EINVAL;
+
+	priv->spec_config.short_repeat = val;
+	return count;
+}
+
+static const struct file_operations fops_spectral_short_repeat = {
+	.read = read_file_spectral_short_repeat,
+	.write = write_file_spectral_short_repeat,
+	.open = simple_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+/******************/
+/* spectral_count */
+/******************/
+
+static ssize_t read_file_spectral_count(struct file *file,
+					char __user *user_buf,
+					size_t count, loff_t *ppos)
+{
+	struct ath9k_htc_priv *priv = file->private_data;
+	char buf[32];
+	unsigned int len;
+
+	len = sprintf(buf, "%d\n", priv->spec_config.count);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_spectral_count(struct file *file,
+					 const char __user *user_buf,
+					 size_t count, loff_t *ppos)
+{
+	struct ath9k_htc_priv *priv = file->private_data;
+	unsigned long val;
+	char buf[32];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (kstrtoul(buf, 0, &val))
+		return -EINVAL;
+
+	if (val < 0 || val > 255)
+		return -EINVAL;
+
+	priv->spec_config.count = val;
+	return count;
+}
+
+static const struct file_operations fops_spectral_count = {
+	.read = read_file_spectral_count,
+	.write = write_file_spectral_count,
+	.open = simple_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+/*******************/
+/* spectral_period */
+/*******************/
+
+static ssize_t read_file_spectral_period(struct file *file,
+					 char __user *user_buf,
+					 size_t count, loff_t *ppos)
+{
+	struct ath9k_htc_priv *priv = file->private_data;
+	char buf[32];
+	unsigned int len;
+
+	len = sprintf(buf, "%d\n", priv->spec_config.period);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_spectral_period(struct file *file,
+					  const char __user *user_buf,
+					  size_t count, loff_t *ppos)
+{
+	struct ath9k_htc_priv *priv = file->private_data;
+	unsigned long val;
+	char buf[32];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (kstrtoul(buf, 0, &val))
+		return -EINVAL;
+
+	if (val < 0 || val > 255)
+		return -EINVAL;
+
+	priv->spec_config.period = val;
+	return count;
+}
+
+static const struct file_operations fops_spectral_period = {
+	.read = read_file_spectral_period,
+	.write = write_file_spectral_period,
+	.open = simple_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+/***********************/
+/* spectral_fft_period */
+/***********************/
+
+static ssize_t read_file_spectral_fft_period(struct file *file,
+					     char __user *user_buf,
+					     size_t count, loff_t *ppos)
+{
+	struct ath9k_htc_priv *priv = file->private_data;
+	char buf[32];
+	unsigned int len;
+
+	len = sprintf(buf, "%d\n", priv->spec_config.fft_period);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_spectral_fft_period(struct file *file,
+					      const char __user *user_buf,
+					      size_t count, loff_t *ppos)
+{
+	struct ath9k_htc_priv *priv = file->private_data;
+	unsigned long val;
+	char buf[32];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (kstrtoul(buf, 0, &val))
+		return -EINVAL;
+
+	if (val < 0 || val > 15)
+		return -EINVAL;
+
+	priv->spec_config.fft_period = val;
+	return count;
+}
+
+static const struct file_operations fops_spectral_fft_period = {
+	.read = read_file_spectral_fft_period,
+	.write = write_file_spectral_fft_period,
+	.open = simple_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+/*******************/
+/* Relay interface */
+/*******************/
+
+static struct dentry *create_buf_file_handler(const char *filename,
+					      struct dentry *parent,
+					      umode_t mode,
+					      struct rchan_buf *buf,
+					      int *is_global)
+{
+	struct dentry *buf_file;
+
+	buf_file = debugfs_create_file(filename, mode, parent, buf,
+				       &relay_file_operations);
+	*is_global = 1;
+	return buf_file;
+}
+
+static int remove_buf_file_handler(struct dentry *dentry)
+{
+	debugfs_remove(dentry);
+
+	return 0;
+}
+
+static struct rchan_callbacks rfs_spec_scan_cb = {
+	.create_buf_file = create_buf_file_handler,
+	.remove_buf_file = remove_buf_file_handler,
+};
+
+/*********************/
+/* Debug Init/Deinit */
+/*********************/
+
+void ath9k_htc_spectral_deinit_debug(struct ath9k_htc_priv *priv)
+{
+	if (config_enabled(CONFIG_ATH9K_DEBUGFS) && priv->rfs_chan_spec_scan) {
+		relay_close(priv->rfs_chan_spec_scan);
+		priv->rfs_chan_spec_scan = NULL;
+	}
+}
+
+void ath9k_htc_spectral_init_debug(struct ath9k_htc_priv *priv)
+{
+	priv->rfs_chan_spec_scan = relay_open("spectral_scan",
+					    priv->debug.debugfs_phy,
+					    1024, 256, &rfs_spec_scan_cb,
+					    NULL);
+	debugfs_create_file("spectral_scan_ctl",
+			    S_IRUSR | S_IWUSR,
+			    priv->debug.debugfs_phy, priv,
+			    &fops_spec_scan_ctl);
+	debugfs_create_file("spectral_short_repeat",
+			    S_IRUSR | S_IWUSR,
+			    priv->debug.debugfs_phy, priv,
+			    &fops_spectral_short_repeat);
+	debugfs_create_file("spectral_count",
+			    S_IRUSR | S_IWUSR,
+			    priv->debug.debugfs_phy, priv,
+			    &fops_spectral_count);
+	debugfs_create_file("spectral_period",
+			    S_IRUSR | S_IWUSR,
+			    priv->debug.debugfs_phy, priv,
+			    &fops_spectral_period);
+	debugfs_create_file("spectral_fft_period",
+			    S_IRUSR | S_IWUSR,
+			    priv->debug.debugfs_phy, priv,
+			    &fops_spectral_fft_period);
+}
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
index e8149e3..d21e685 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
@@ -1010,6 +1010,23 @@ static bool ath9k_rx_prepare(struct ath9k_htc_priv *priv,
 	 * separately to avoid doing two lookups for a rate for each frame.
 	 */
 	hdr = (struct ieee80211_hdr *)skb->data;
+
+	/*
+	 * Process PHY errors and return so that the packet
+	 * can be dropped.
+	 */
+  #ifdef CONFIG_ATH9K_HTC_DEBUGFS
+	if (rx_stats.rs_status & ATH9K_RXERR_PHY) {
+    /* TODO: Not using DFS processing now. */
+		if (ath_process_fft(priv->ah, hdr, priv->hw, priv->rfs_chan_spec_scan,
+      &rx_stats, rx_status->mactime, true)) {
+      /* TODO: Add code for collecting statistics about spectral scan */
+    }
+
+		goto rx_next;
+	}
+  #endif
+
 	if (!ath9k_cmn_rx_accept(common, hdr, rx_status, &rx_stats,
 			&decrypt_error, priv->rxfilter))
 		goto rx_next;
-- 
1.7.5.4