Hi Sean,

quoted

quoted

quoted

quoted

+
+static int mtk_hci_wmt_sync(struct hci_dev *hdev, u8 op, u8 flag, u16 plen,
+			    const void *param)
+{
+	struct mtk_hci_wmt_cmd wc;
+	struct mtk_wmt_hdr *hdr;
+	struct sk_buff *skb;
+	u32 hlen;
+
+	hlen = sizeof(*hdr) + plen;
+	if (hlen > 255)
+		return -EINVAL;
+
+	hdr = (struct mtk_wmt_hdr *)&wc;
+	hdr->dir = 1;
+	hdr->op = op;
+	hdr->dlen = cpu_to_le16(plen + 1);
+	hdr->flag = flag;
+	memcpy(wc.data, param, plen);
+
+	atomic_inc(&hdev->cmd_cnt);

Why are you doing this one. It will need a comment here if really needed. However I doubt that this is needed. You are only using it from hdev->setup and hdev->shutdown callbacks.

An increment on cmd_cnt is really needed because hci_cmd_work would check whether cmd_cnt is positive and then has a decrement on cmd_cnt before a packet is being sent out.

okay will add a comment.

but you are in ->setup callback this time. So if you need this, then all the other ->setup routines would actually fail as well. Either this is leftover from when you did things in ->probe or ->open or this is some thing we might better fix properly in the core instead of papering over it. Can you recheck if this is really needed.

I added a counter print and the counter increments as below

	/* atomic_inc(&hdev->cmd_cnt); */
       pr_info("cmd_cnt = %d\n" , atomic_read(&hdev->cmd_cnt));

       skb = __hci_cmd_sync_ev(hdev, 0xfc6f, hlen, &wc, HCI_VENDOR_PKT,
                               HCI_INIT_TIMEOUT);

and the log show up that 


[  334.049156] Bluetooth: hci0: command 0xfc6f tx timeout
[  334.054840] cmd_cnt = 0
[  336.065076] Bluetooth: hci0: command 0xfc6f tx timeout
[  336.070795] cmd_cnt = 0
[  338.080997] Bluetooth: hci0: command 0xfc6f tx timeout
[  338.086683] cmd_cnt = 0
[  340.096907] Bluetooth: hci0: command 0xfc6f tx timeout
[  340.102609] cmd_cnt = 0
[  342.112824] Bluetooth: hci0: command 0xfc6f tx timeout
[  342.118520] cmd_cnt = 0
[  344.128747] Bluetooth: hci0: command 0xfc6f tx timeout
[  344.134454] cmd_cnt = 0
[  346.144667] Bluetooth: hci0: command 0xfc6f tx timeout
[  346.150372] cmd_cnt = 0


The packet is dropped by hci_cmd_work at [1], so I also wondered why the
other vendor driver works, it seems the counter needs to be incremented
before every skb is being queued to cmd_q.

4257 static void hci_cmd_work(struct work_struct *work)
4258 {
4259         struct hci_dev *hdev = container_of(work, struct hci_dev, cmd_work);
4260         struct sk_buff *skb;
4261
4262         BT_DBG("%s cmd_cnt %d cmd queued %d", hdev->name,
4263                atomic_read(&hdev->cmd_cnt), skb_queue_len(&hdev->cmd_q));
4264
4265         /* Send queued commands */

[1]
4266         if (atomic_read(&hdev->cmd_cnt)) { /* dropped when cmd_cnt is zero */
4267                 skb = skb_dequeue(&hdev->cmd_q);
4268                 if (!skb)
4269                         return;
4270
4271                 kfree_skb(hdev->sent_cmd);
4272
4273                 hdev->sent_cmd = skb_clone(skb, GFP_KERNEL);
4274                 if (hdev->sent_cmd) {
4275                         atomic_dec(&hdev->cmd_cnt);  /* cmd_cnt-- */
4276                         hci_send_frame(hdev, skb);

actually the command also needs to better go via the raw_q anyway since it doesn?t come back with the cmd status or cmd complete. You have it waiting for a vendor event. Maybe with is something we need to consider with __hci_cmd_sync_ev anyway.

Johan would know best since he wrote that code. Anyway, we should fix that in the core and not have you hack around it.

Regards

Marcel