Bluetooth: Use proper timer for hci command timout

Use proper timer instead of hci command flow control to timeout
failed hci commands. Otherwise stack ends up sending commands
when flow control is used to block new commands.

2010-09-01 18:29:41.592132 < HCI Command: Remote Name Request (0x01|0x0019) plen 10
    bdaddr 00:16:CF:E1:C7:D7 mode 2 clkoffset 0x0000
2010-09-01 18:29:41.592681 > HCI Event: Command Status (0x0f) plen 4
    Remote Name Request (0x01|0x0019) status 0x00 ncmd 0
2010-09-01 18:29:51.022033 < HCI Command: Remote Name Request Cancel (0x01|0x001a) plen 6
    bdaddr 00:16:CF:E1:C7:D7

Signed-off-by: Ville Tervo <ville.tervo@nokia.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

include/net/bluetooth/hci.h

@@ -119,6 +119,7 @@ enum {
 #define HCI_PAIRING_TIMEOUT	(60000)	/* 60 seconds */
 #define HCI_IDLE_TIMEOUT	(6000)	/* 6 seconds */
 #define HCI_INIT_TIMEOUT	(10000)	/* 10 seconds */
+#define HCI_CMD_TIMEOUT		(1000)	/* 1 seconds */
 
 /* HCI data types */
 #define HCI_COMMAND_PKT		0x01
@@ -244,6 +245,8 @@ enum {
 #define HCI_AT_GENERAL_BONDING_MITM	0x05
 
 /* -----  HCI Commands ---- */
+#define HCI_OP_NOP			0x0000
+
 #define HCI_OP_INQUIRY			0x0401
 struct hci_cp_inquiry {
 	__u8     lap[3];

include/net/bluetooth/hci_core.h

@@ -132,7 +132,6 @@ struct hci_dev {
 	unsigned int	sco_pkts;
 	unsigned int	le_pkts;
 
-	unsigned long	cmd_last_tx;
 	unsigned long	acl_last_tx;
 	unsigned long	sco_last_tx;
 	unsigned long	le_last_tx;
@@ -143,6 +142,7 @@ struct hci_dev {
 	struct work_struct	power_off;
 	struct timer_list	off_timer;
 
+	struct timer_list	cmd_timer;
 	struct tasklet_struct	cmd_task;
 	struct tasklet_struct	rx_task;
 	struct tasklet_struct	tx_task;

net/bluetooth/hci_core.c

@@ -41,6 +41,7 @@
 #include <linux/interrupt.h>
 #include <linux/notifier.h>
 #include <linux/rfkill.h>
+#include <linux/timer.h>
 #include <net/sock.h>
 
 #include <asm/system.h>
@@ -623,6 +624,7 @@ static int hci_dev_do_close(struct hci_dev *hdev)
 
 	/* Drop last sent command */
 	if (hdev->sent_cmd) {
+		del_timer_sync(&hdev->cmd_timer);
 		kfree_skb(hdev->sent_cmd);
 		hdev->sent_cmd = NULL;
 	}
@@ -1066,6 +1068,16 @@ int hci_remove_link_key(struct hci_dev *hdev, bdaddr_t *bdaddr)
 	return 0;
 }
 
+/* HCI command timer function */
+static void hci_cmd_timer(unsigned long arg)
+{
+	struct hci_dev *hdev = (void *) arg;
+
+	BT_ERR("%s command tx timeout", hdev->name);
+	atomic_set(&hdev->cmd_cnt, 1);
+	tasklet_schedule(&hdev->cmd_task);
+}
+
 /* Register HCI device */
 int hci_register_dev(struct hci_dev *hdev)
 {
@@ -1112,6 +1124,8 @@ int hci_register_dev(struct hci_dev *hdev)
 	skb_queue_head_init(&hdev->cmd_q);
 	skb_queue_head_init(&hdev->raw_q);
 
+	setup_timer(&hdev->cmd_timer, hci_cmd_timer, (unsigned long) hdev);
+
 	for (i = 0; i < NUM_REASSEMBLY; i++)
 		hdev->reassembly[i] = NULL;
 
@@ -2004,11 +2018,6 @@ static void hci_cmd_task(unsigned long arg)
 
 	BT_DBG("%s cmd %d", hdev->name, atomic_read(&hdev->cmd_cnt));
 
-	if (!atomic_read(&hdev->cmd_cnt) && time_after(jiffies, hdev->cmd_last_tx + HZ)) {
-		BT_ERR("%s command tx timeout", hdev->name);
-		atomic_set(&hdev->cmd_cnt, 1);
-	}
-
 	/* Send queued commands */
 	if (atomic_read(&hdev->cmd_cnt)) {
 		skb = skb_dequeue(&hdev->cmd_q);
@@ -2021,7 +2030,8 @@ static void hci_cmd_task(unsigned long arg)
 		if (hdev->sent_cmd) {
 			atomic_dec(&hdev->cmd_cnt);
 			hci_send_frame(skb);
-			hdev->cmd_last_tx = jiffies;
+			mod_timer(&hdev->cmd_timer,
+				  jiffies + msecs_to_jiffies(HCI_CMD_TIMEOUT));
 		} else {
 			skb_queue_head(&hdev->cmd_q, skb);
 			tasklet_schedule(&hdev->cmd_task);

net/bluetooth/hci_event.c

@@ -1732,6 +1732,9 @@ static inline void hci_cmd_complete_evt(struct hci_dev *hdev, struct sk_buff *sk
 		break;
 	}
 
+	if (ev->opcode != HCI_OP_NOP)
+		del_timer(&hdev->cmd_timer);
+
 	if (ev->ncmd) {
 		atomic_set(&hdev->cmd_cnt, 1);
 		if (!skb_queue_empty(&hdev->cmd_q))
@@ -1807,6 +1810,9 @@ static inline void hci_cmd_status_evt(struct hci_dev *hdev, struct sk_buff *skb)
 		break;
 	}
 
+	if (ev->opcode != HCI_OP_NOP)
+		del_timer(&hdev->cmd_timer);
+
 	if (ev->ncmd) {
 		atomic_set(&hdev->cmd_cnt, 1);
 		if (!skb_queue_empty(&hdev->cmd_q))