mt76: mt7915: add twt_stats knob in debugfs

Introduce twt_stats knob in debugfs in order to dump established
agreements

Tested-by: Peter Chiu <chui-hao.chiu@mediatek.com>
Tested-by: Evelyn Tsai <evelyn.tsai@mediatek.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7915/debugfs.c

@@ -437,6 +437,32 @@ mt7915_read_rate_txpower(struct seq_file *s, void *data)
 	return 0;
 }
 
+static int
+mt7915_twt_stats(struct seq_file *s, void *data)
+{
+	struct mt7915_dev *dev = dev_get_drvdata(s->private);
+	struct mt7915_twt_flow *iter;
+
+	rcu_read_lock();
+
+	seq_puts(s, "     wcid |       id |    flags |      exp | mantissa");
+	seq_puts(s, " | duration |            tsf |\n");
+	list_for_each_entry_rcu(iter, &dev->twt_list, list)
+		seq_printf(s,
+			"%9d | %8d | %5c%c%c%c | %8d | %8d | %8d | %14lld |\n",
+			iter->wcid, iter->id,
+			iter->sched ? 's' : 'u',
+			iter->protection ? 'p' : '-',
+			iter->trigger ? 't' : '-',
+			iter->flowtype ? '-' : 'a',
+			iter->exp, iter->mantissa,
+			iter->duration, iter->tsf);
+
+	rcu_read_unlock();
+
+	return 0;
+}
+
 int mt7915_init_debugfs(struct mt7915_dev *dev)
 {
 	struct dentry *dir;
@@ -454,6 +480,8 @@ int mt7915_init_debugfs(struct mt7915_dev *dev)
 	debugfs_create_file("implicit_txbf", 0600, dir, dev,
 			    &fops_implicit_txbf);
 	debugfs_create_u32("dfs_hw_pattern", 0400, dir, &dev->hw_pattern);
+	debugfs_create_devm_seqfile(dev->mt76.dev, "twt_stats", dir,
+				    mt7915_twt_stats);
 	/* test knobs */
 	debugfs_create_file("radar_trigger", 0200, dir, dev,
 			    &fops_radar_trigger);