Commit 3f27e95b authored by Johan Hedberg's avatar Johan Hedberg Committed by Gustavo Padovan
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Bluetooth: Add initial reliable packet support for Three-wire UART 



This patch adds initial support for reliable packets along with the
necessary retransmission timer for the Three-wire UART HCI driver.

Signed-off-by: default avatarJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: default avatarGustavo Padovan <gustavo.padovan@collabora.co.uk>
parent 7d664fba

drivers/bluetooth/hci_h5.c

+56 −0
Original line number Diff line number Diff line
@@ -30,6 +30,10 @@ 


#include "hci_uart.h"



#define H5_TXWINSIZE	4



#define H5_ACK_TIMEOUT	msecs_to_jiffies(250)



struct h5 {

	struct sk_buff_head unack;	/* Unack'ed packets queue */

	struct sk_buff_head rel;	/* Reliable packets queue */
@@ -37,11 +41,34 @@ struct h5 { 


	struct sk_buff *rx_skb;



	struct timer_list timer;	/* Retransmission timer */



	bool txack_req;



	u8 msgq_txseq;

};



static void h5_timed_event(unsigned long arg)

{

	struct hci_uart *hu = (struct hci_uart *) arg;

	struct h5 *h5 = hu->priv;

	struct sk_buff *skb;

	unsigned long flags;



	BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen);



	spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);



	while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) {

		h5->msgq_txseq = (h5->msgq_txseq - 1) & 0x07;

		skb_queue_head(&h5->rel, skb);

	}



	spin_unlock_irqrestore(&h5->unack.lock, flags);



	hci_uart_tx_wakeup(hu);

}



static int h5_open(struct hci_uart *hu)

{

	struct h5 *h5;
@@ -58,6 +85,10 @@ static int h5_open(struct hci_uart *hu) 
	skb_queue_head_init(&h5->rel);

	skb_queue_head_init(&h5->unrel);



	init_timer(&h5->timer);

	h5->timer.function = h5_timed_event;

	h5->timer.data = (unsigned long) hu;



	return 0;

}
@@ -69,6 +100,8 @@ static int h5_close(struct hci_uart *hu) 
	skb_queue_purge(&h5->rel);

	skb_queue_purge(&h5->unrel);



	del_timer(&h5->timer);



	kfree(h5);



	return 0;
@@ -123,6 +156,7 @@ static struct sk_buff *h5_prepare_ack(struct h5 *h5) 
static struct sk_buff *h5_dequeue(struct hci_uart *hu)

{

	struct h5 *h5 = hu->priv;

	unsigned long flags;

	struct sk_buff *skb, *nskb;



	if ((skb = skb_dequeue(&h5->unrel)) != NULL) {
@@ -136,6 +170,28 @@ static struct sk_buff *h5_dequeue(struct hci_uart *hu) 
		BT_ERR("Could not dequeue pkt because alloc_skb failed");

	}



	spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);



	if (h5->unack.qlen >= H5_TXWINSIZE)

		goto unlock;



	if ((skb = skb_dequeue(&h5->rel)) != NULL) {

		nskb = h5_prepare_pkt(h5, skb);



		if (nskb) {

			__skb_queue_tail(&h5->unack, skb);

			mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT);

			spin_unlock_irqrestore(&h5->unack.lock, flags);

			return nskb;

		}



		skb_queue_head(&h5->rel, skb);

		BT_ERR("Could not dequeue pkt because alloc_skb failed");

	}



unlock:

	spin_unlock_irqrestore(&h5->unack.lock, flags);



	if (h5->txack_req)

		return h5_prepare_ack(h5);