[PATCH wireless-next v6 0/1] wifi: cfg80211/mac80211: add support to handle incumbent signal detected event

[PATCH wireless-next v6 0/1] wifi: cfg80211/mac80211: add support to handle incumbent signal detected event

[Amith A]

This patch series adds support to handle incumbent signal interference
detected event in 6 GHz band. When an incumbent signal is detected by an
AP/mesh interface operating in 6 GHz band, the AP/mesh is expected to
vacate the channels affected by it.

Driver is expected to call the newly introduced API with required
information to notify the interference detection. This information will be
ultimately sent to user space via NL802111 command. User space is expected
to process it and take further action - vacate the channel, or reduce the
bandwidth.

Aditya Kumar Singh (1):
  wifi: mac80211_hwsim: add incumbent signal interference detection
    support
---
Changes in v6:
 - Simplified chanctx iterator plumbing, tightened input length validation
   replaced strsep/kstrtou32 parsing with sscanf and collapsed local
   variables to reduce complexity.
 - Removed patch "wifi: cfg80211: add support to handle incumbent
   signal detected event from mac80211/driver" from the series as it
   got accepted.
Changes in v5:
 - Made chandef const in cfg80211_incumbent_signal_notify()
 - Removed mac80211 wrapper ieee80211_incumbent_signal_detected(). 
   Driver/hwsim calls cfg80211 notify directly.
 - In mac80211_hwsim, switched debugfs to custom fops with .write that
   accepts “freq_mhz bitmap”. Now 6 GHz chanctx is selected by primary
   20 MHz center.

Changes in v4:
 - Restored gfp_t in cfg80211_incumbent_signal_notify().
 - Dropped incumbt_sig_intf_bmap from ieee80211_chanctx_conf and passed
   bitmap directly.
 - Updated trace/call path: api_incumbent_signal_detected() to take bitmap
 - Simplified hwsim: removed helper struct.

Changes in v3:
 - Removed the workqueue mechanism in ieee80211_incumbent_signal_detected(),
   exported the cfg80211_ function that sends the NL80211 command and called
   it from ieee80211_incumbent_signal_detected() directly.
 - Renamed nl80211_incumbent_signal_notify() to
   cfg80211_incumbent_signal_notify() and removed the gfp argument from it.

Changes in v2:
 - Updated the kernel doc of NL80211_ATTR_INCUMBENT_SIGNAL_INTERFERENCE_BITMAP
   to include details of how it interacts with puncturing.
 - Rebased on ToT
---
 drivers/net/wireless/virtual/mac80211_hwsim.c | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)


base-commit: 5d048bbed1bb2bbef612dad0bb9c177c434e63a4
-- 
2.34.1

[PATCH wireless-next v6 1/1] wifi: mac80211_hwsim: add incumbent signal interference detection support

[Amith A]

From: Aditya Kumar Singh <aditya.kumar.singh@oss.qualcomm.com>

Add a debugfs 'simulate_incumbent_signal_interference' with custom
file_operations and a .write that accepts "<freq_mhz> <bitmap>". The
handler selects the 6 GHz chanctx whose primary 20 MHz center matches
<freq_mhz> and reports the event via cfg80211_incumbent_signal_notify().
The bitmap marks affected 20 MHz segments within the current chandef
(lowest bit = lowest segment)

Signed-off-by: Aditya Kumar Singh <aditya.kumar.singh@oss.qualcomm.com>
Signed-off-by: Amith A <amith.a@oss.qualcomm.com>
---
 drivers/net/wireless/virtual/mac80211_hwsim.c | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)

diff --git a/drivers/net/wireless/virtual/mac80211_hwsim.c b/drivers/net/wireless/virtual/mac80211_hwsim.c
index 475918ee8132..37d1c9022752 100644
--- a/drivers/net/wireless/virtual/mac80211_hwsim.c
+++ b/drivers/net/wireless/virtual/mac80211_hwsim.c
@@ -36,6 +36,8 @@
 #include <linux/virtio.h>
 #include <linux/virtio_ids.h>
 #include <linux/virtio_config.h>
+#include <linux/uaccess.h>
+#include <linux/string.h>
 #include "mac80211_hwsim.h"
 
 #define WARN_QUEUE 100
@@ -1201,6 +1203,65 @@ static const struct file_operations hwsim_background_cac_ops = {
 	.llseek = default_llseek,
 };
 
+struct hwsim_chanctx_iter_arg {
+	struct ieee80211_chanctx_conf *conf;
+	u32 freq_mhz;
+};
+
+static void hwsim_6ghz_chanctx_iter(struct ieee80211_hw *hw,
+				    struct ieee80211_chanctx_conf *conf,
+				    void *data)
+{
+	struct hwsim_chanctx_iter_arg *arg = data;
+
+	if (conf->def.chan &&
+	    conf->def.chan->band == NL80211_BAND_6GHZ &&
+	    conf->def.chan->center_freq == arg->freq_mhz)
+		arg->conf = conf;
+}
+
+static ssize_t hwsim_simulate_incumbent_signal_write(struct file *file,
+						     const char __user *ubuf,
+						     size_t len, loff_t *ppos)
+{
+	struct mac80211_hwsim_data *data = file->private_data;
+	struct hwsim_chanctx_iter_arg arg = {};
+	u32 bitmap;
+	char buf[64];
+
+	if (!len || len > sizeof(buf) - 1)
+		return -EINVAL;
+
+	if (copy_from_user(buf, ubuf, len))
+		return -EFAULT;
+	buf[len] = '\0';
+
+	if (sscanf(buf, "%u %i", &arg.freq_mhz, &bitmap) != 2)
+		return -EINVAL;
+
+	if (!arg.freq_mhz)
+		return -EINVAL;
+
+	ieee80211_iter_chan_contexts_atomic(data->hw,
+					    hwsim_6ghz_chanctx_iter,
+					    &arg);
+
+	if (!arg.conf)
+		return -EINVAL;
+
+	cfg80211_incumbent_signal_notify(data->hw->wiphy,
+					 &arg.conf->def,
+					 bitmap,
+					 GFP_KERNEL);
+
+	return len;
+}
+
+static const struct file_operations hwsim_simulate_incumbent_signal_fops = {
+	.open	= simple_open,
+	.write	= hwsim_simulate_incumbent_signal_write,
+};
+
 static int hwsim_fops_group_read(void *dat, u64 *val)
 {
 	struct mac80211_hwsim_data *data = dat;
@@ -5948,6 +6009,9 @@ static int mac80211_hwsim_new_radio(struct genl_info *info,
 		debugfs_create_file("dfs_background_cac", 0200,
 				    data->debugfs,
 				    data, &hwsim_background_cac_ops);
+	debugfs_create_file("simulate_incumbent_signal_interference", 0200,
+			    data->debugfs,
+			    data, &hwsim_simulate_incumbent_signal_fops);
 
 	if (param->pmsr_capa) {
 		data->pmsr_capa = *param->pmsr_capa;
-- 
2.34.1