Commit c0a1b73c authored by Johan Hedberg's avatar Johan Hedberg Committed by Gustavo Padovan
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Bluetooth: Add initial packet sending support to Three-wire UART 



This patch adds initial packed encoding and sending support to the
Three-wire UART HCI transport driver.

Signed-off-by: default avatarJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: default avatarGustavo Padovan <gustavo.padovan@collabora.co.uk>
parent bc1f35b9

drivers/bluetooth/hci_h5.c

+98 −7
Original line number Diff line number Diff line
@@ -30,6 +30,9 @@ 


#include "hci_uart.h"



#define HCI_3WIRE_ACK_PKT	0

#define HCI_3WIRE_LINK_PKT	15



#define H5_TXWINSIZE	4



#define H5_ACK_TIMEOUT	msecs_to_jiffies(250)
@@ -60,7 +63,8 @@ struct h5 { 


	bool			txack_req;



	u8			msgq_txseq;

	u8			next_ack;

	u8			next_seq;

};



static void h5_reset_rx(struct h5 *h5);
@@ -77,7 +81,7 @@ static void h5_timed_event(unsigned long arg) 
	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;

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

		skb_queue_head(&h5->rel, skb);

	}
@@ -355,12 +359,98 @@ static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb) 
	return 0;

}



static struct sk_buff *h5_prepare_pkt(struct h5 *h5, struct sk_buff *skb)

static void h5_slip_delim(struct sk_buff *skb)

{

	const char delim = SLIP_DELIMITER;



	memcpy(skb_put(skb, 1), &delim, 1);

}



static void h5_slip_one_byte(struct sk_buff *skb, u8 c)

{

	const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM };

	const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC };



	switch (c) {

	case SLIP_DELIMITER:

		memcpy(skb_put(skb, 2), &esc_delim, 2);

		break;

	case SLIP_ESC:

		memcpy(skb_put(skb, 2), &esc_esc, 2);

		break;

	default:

		memcpy(skb_put(skb, 1), &c, 1);

	}

}



static struct sk_buff *h5_build_pkt(struct h5 *h5, bool rel, u8 pkt_type,

				    const u8 *data, size_t len)

{

	struct sk_buff *nskb;

	u8 hdr[4];

	int i;



	/*

	 * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2

	 * (because bytes 0xc0 and 0xdb are escaped, worst case is when

	 * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0

	 * delimiters at start and end).

	 */

	nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);

	if (!nskb)

		return NULL;



	bt_cb(nskb)->pkt_type = pkt_type;



	h5_slip_delim(nskb);



	hdr[0] = h5->next_ack << 3;

	h5->txack_req = false;



	if (rel) {

		hdr[0] |= 1 << 7;

		hdr[0] |= h5->next_seq;

		h5->next_seq = (h5->next_seq + 1) % 8;

	}



	hdr[1] = pkt_type | ((len & 0x0f) << 4);

	hdr[2] = len >> 4;

	hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff);



	for (i = 0; i < 4; i++)

		h5_slip_one_byte(nskb, hdr[i]);



	for (i = 0; i < len; i++)

		h5_slip_one_byte(nskb, data[i]);



	h5_slip_delim(nskb);



	return nskb;

}



static struct sk_buff *h5_prepare_pkt(struct h5 *h5, u8 pkt_type,

				      const u8 *data, size_t len)

{

	bool rel;



	switch (pkt_type) {

	case HCI_ACLDATA_PKT:

	case HCI_COMMAND_PKT:

		rel = true;

		break;

	case HCI_SCODATA_PKT:

	case HCI_3WIRE_LINK_PKT:

	case HCI_3WIRE_ACK_PKT:

		rel = false;

		break;

	default:

		BT_ERR("Unknown packet type %u", pkt_type);

		return NULL;

	}



	return h5_build_pkt(h5, rel, pkt_type, data, len);

}



static struct sk_buff *h5_prepare_ack(struct h5 *h5)

{

	h5->txack_req = false;
@@ -374,7 +464,8 @@ static struct sk_buff *h5_dequeue(struct hci_uart *hu) 
	struct sk_buff *skb, *nskb;



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

		nskb = h5_prepare_pkt(h5, skb);

		nskb = h5_prepare_pkt(h5, bt_cb(skb)->pkt_type,

				      skb->data, skb->len);

		if (nskb) {

			kfree_skb(skb);

			return nskb;
@@ -390,8 +481,8 @@ static struct sk_buff *h5_dequeue(struct hci_uart *hu) 
		goto unlock;



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

		nskb = h5_prepare_pkt(h5, skb);



		nskb = h5_prepare_pkt(h5, bt_cb(skb)->pkt_type,

				      skb->data, skb->len);

		if (nskb) {

			__skb_queue_tail(&h5->unack, skb);

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