ath9k: add spectral scan feature
Adds the spectral scan feature for ath9k. AR92xx and AR93xx chips
are supported for now. The spectral scan is triggered by configuring
a mode through a debugfs control file. Samples can be gathered via
another relay debugfs file.
Essentially, to try it out:
echo chanscan > /sys/kernel/debug/ieee80211/phy0/ath9k/spectral_scan_ctl
iw dev wlan0 scan
cat /sys/kernel/debug/ieee80211/phy0/ath9k/spectral_scan0 > samples
echo disable > /sys/kernel/debug/ieee80211/phy0/ath9k/spectral_scan_ctl
This feature is still experimental.
The special "chanscan" mode is used to perform spectral scan while
mac80211 is scanning for channels. To allow this,
sw_scan_start/complete() ops have been added.
The patch contains code snippets and information from Zefir Kurtisi and
information provided by Adrian Chadd and Felix Fietkau.
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
index 13ff9ed..75b504b 100644
--- a/drivers/net/wireless/ath/ath9k/debug.c
+++ b/drivers/net/wireless/ath/ath9k/debug.c
@@ -17,6 +17,7 @@
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/export.h>
+#include <linux/relay.h>
#include <asm/unaligned.h>
#include "ath9k.h"
@@ -966,6 +967,112 @@
.llseek = default_llseek,
};
+static ssize_t read_file_spec_scan_ctl(struct file *file, char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct ath_softc *sc = file->private_data;
+ char *mode = "";
+ unsigned int len;
+
+ switch (sc->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 ath_softc *sc = file->private_data;
+ struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+ 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 (strncmp("trigger", buf, 7) == 0) {
+ ath9k_spectral_scan_trigger(sc->hw);
+ } else if (strncmp("background", buf, 9) == 0) {
+ ath9k_spectral_scan_config(sc->hw, SPECTRAL_BACKGROUND);
+ ath_dbg(common, CONFIG, "spectral scan: background mode enabled\n");
+ } else if (strncmp("chanscan", buf, 8) == 0) {
+ ath9k_spectral_scan_config(sc->hw, SPECTRAL_CHANSCAN);
+ ath_dbg(common, CONFIG, "spectral scan: channel scan mode enabled\n");
+ } else if (strncmp("manual", buf, 6) == 0) {
+ ath9k_spectral_scan_config(sc->hw, SPECTRAL_MANUAL);
+ ath_dbg(common, CONFIG, "spectral scan: manual mode enabled\n");
+ } else if (strncmp("disable", buf, 7) == 0) {
+ ath9k_spectral_scan_config(sc->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,
+};
+
+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;
+}
+
+void ath_debug_send_fft_sample(struct ath_softc *sc,
+ struct fft_sample_tlv *fft_sample_tlv)
+{
+ if (!sc->rfs_chan_spec_scan)
+ return;
+
+ relay_write(sc->rfs_chan_spec_scan, fft_sample_tlv,
+ fft_sample_tlv->length + sizeof(*fft_sample_tlv));
+}
+
+static struct rchan_callbacks rfs_spec_scan_cb = {
+ .create_buf_file = create_buf_file_handler,
+ .remove_buf_file = remove_buf_file_handler,
+};
+
+
static ssize_t read_file_regidx(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
@@ -1780,6 +1887,14 @@
&fops_base_eeprom);
debugfs_create_file("modal_eeprom", S_IRUSR, sc->debug.debugfs_phy, sc,
&fops_modal_eeprom);
+ sc->rfs_chan_spec_scan = relay_open("spectral_scan",
+ sc->debug.debugfs_phy,
+ 262144, 4, &rfs_spec_scan_cb,
+ NULL);
+ debugfs_create_file("spectral_scan_ctl", S_IRUSR | S_IWUSR,
+ sc->debug.debugfs_phy, sc,
+ &fops_spec_scan_ctl);
+
#ifdef CONFIG_ATH9K_MAC_DEBUG
debugfs_create_file("samples", S_IRUSR, sc->debug.debugfs_phy, sc,
&fops_samps);