mt76x2: dfs: avoid tasklet scheduling during mt76x2_dfs_init_params()

Substitute tasklet_kill with tasklet_disable/tasklet_enable in order to
guarantee dfs tasklet can not be executed during dfs parameter
initialization

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/mediatek/mt76/mt76x2_dfs.c

@@ -460,7 +460,6 @@ void mt76x2_dfs_init_params(struct mt76x2_dev *dev)
 {
 	struct cfg80211_chan_def *chandef = &dev->mt76.chandef;
 
-	tasklet_kill(&dev->dfs_pd.dfs_tasklet);
 	if (chandef->chan->flags & IEEE80211_CHAN_RADAR) {
 		mt76x2_dfs_set_bbp_params(dev);
 		/* enable debug mode */

drivers/net/wireless/mediatek/mt76/mt76x2_main.c

@@ -127,6 +127,7 @@ mt76x2_set_channel(struct mt76x2_dev *dev, struct cfg80211_chan_def *chandef)
 	mt76_set_channel(&dev->mt76);
 
 	tasklet_disable(&dev->pre_tbtt_tasklet);
+	tasklet_disable(&dev->dfs_pd.dfs_tasklet);
 	cancel_delayed_work_sync(&dev->cal_work);
 
 	mt76x2_mac_stop(dev, true);
@@ -139,6 +140,7 @@ mt76x2_set_channel(struct mt76x2_dev *dev, struct cfg80211_chan_def *chandef)
 	mt76x2_dfs_init_params(dev);
 
 	mt76x2_mac_resume(dev);
+	tasklet_enable(&dev->dfs_pd.dfs_tasklet);
 	tasklet_enable(&dev->pre_tbtt_tasklet);
 
 	return ret;