From: Johan Hedberg <johan.hedberg@xxxxxxxxx>
This patch adds basic support for parsing and sending Three-wire UART
Link Control packets.
Signed-off-by: Johan Hedberg <johan.hedberg@xxxxxxxxx>
---
drivers/bluetooth/hci_h5.c | 96 ++++++++++++++++++++++++++++++++++++--------
1 file changed, 79 insertions(+), 17 deletions(-)
diff --git a/drivers/bluetooth/hci_h5.c b/drivers/bluetooth/hci_h5.c
index 7a41791..252f364 100644
--- a/drivers/bluetooth/hci_h5.c
+++ b/drivers/bluetooth/hci_h5.c
@@ -36,6 +36,7 @@
#define H5_TXWINSIZE 4
#define H5_ACK_TIMEOUT msecs_to_jiffies(250)
+#define H5_SYNC_TIMEOUT msecs_to_jiffies(100)
/*
* Maximum Three-wire packet:
@@ -65,7 +66,6 @@ struct h5 {
size_t rx_pending; /* Expecting more bytes */
bool rx_esc; /* SLIP escape mode */
u8 rx_ack; /* Last ack number received */
- u8 rx_seq; /* Last seq number received */
int (*rx_func) (struct hci_uart *hu, u8 c);
@@ -73,6 +73,7 @@ struct h5 {
bool tx_ack_req; /* Pending ack to send */
u8 tx_seq; /* Next seq number to send */
+ u8 tx_ack; /* Next ack number to send */
};
static void h5_reset_rx(struct h5 *h5);
@@ -98,9 +99,26 @@ static void h5_timed_event(unsigned long arg)
hci_uart_tx_wakeup(hu);
}
+static void h5_link_control(struct hci_uart *hu, const void *data, size_t len)
+{
+ struct h5 *h5 = hu->priv;
+ struct sk_buff *nskb;
+
+ nskb = alloc_skb(3, GFP_ATOMIC);
+ if (!nskb)
+ return;
+
+ bt_cb(nskb)->pkt_type = HCI_3WIRE_LINK_PKT;
+
+ memcpy(skb_put(nskb, len), data, len);
+
+ skb_queue_tail(&h5->unrel, nskb);
+}
+
static int h5_open(struct hci_uart *hu)
{
struct h5 *h5;
+ const unsigned char sync[] = { 0x01, 0x7e };
BT_DBG("hu %p", hu);
@@ -120,6 +138,10 @@ static int h5_open(struct hci_uart *hu)
h5->timer.function = h5_timed_event;
h5->timer.data = (unsigned long) hu;
+ /* Send initial sync request */
+ h5_link_control(hu, sync, sizeof(sync));
+ mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
+
return 0;
}
@@ -148,6 +170,8 @@ static void h5_pkt_cull(struct h5 *h5)
spin_lock_irqsave(&h5->unack.lock, flags);
to_remove = skb_queue_len(&h5->unack);
+ if (to_remove == 0)
+ goto unlock;
seq = h5->tx_seq;
@@ -174,12 +198,44 @@ static void h5_pkt_cull(struct h5 *h5)
if (skb_queue_empty(&h5->unack))
del_timer(&h5->timer);
+unlock:
spin_unlock_irqrestore(&h5->unack.lock, flags);
}
static void h5_handle_internal_rx(struct hci_uart *hu)
{
+ struct h5 *h5 = hu->priv;
+ const unsigned char sync_req[] = { 0x01, 0x7e };
+ const unsigned char sync_rsp[] = { 0x02, 0x7d };
+ const unsigned char conf_req[] = { 0x03, 0xfc, 0x01 };
+ const unsigned char conf_rsp[] = { 0x04, 0x7b, 0x01 };
+ const unsigned char *hdr = h5->rx_skb->data;
+ const unsigned char *data = &h5->rx_skb->data[4];
+
BT_DBG("%s", hu->hdev->name);
+
+ if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT)
+ return;
+
+ if (H5_HDR_LEN(hdr) < 2)
+ return;
+
+ if (memcmp(data, sync_req, 2) == 0) {
+ h5_link_control(hu, sync_rsp, 2);
+ } else if (memcmp(data, sync_rsp, 2) == 0) {
+ h5_link_control(hu, conf_req, 3);
+ } else if (memcmp(data, conf_req, 2) == 0) {
+ h5_link_control(hu, conf_rsp, 2);
+ h5_link_control(hu, conf_req, 3);
+ } else if (memcmp(data, conf_rsp, 2) == 0) {
+ BT_DBG("Three-wire init sequence complete");
+ return;
+ } else {
+ BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]);
+ return;
+ }
+
+ hci_uart_tx_wakeup(hu);
}
static void h5_complete_rx_pkt(struct hci_uart *hu)
@@ -190,8 +246,9 @@ static void h5_complete_rx_pkt(struct hci_uart *hu)
BT_DBG("%s", hu->hdev->name);
if (H5_HDR_RELIABLE(hdr)) {
- h5->tx_seq = (h5->tx_seq + 1) % 8;
+ h5->tx_ack = (h5->tx_ack + 1) % 8;
h5->tx_ack_req = true;
+ hci_uart_tx_wakeup(hu);
}
h5->rx_ack = H5_HDR_ACK(hdr);
@@ -257,15 +314,20 @@ static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c)
BT_DBG("%s 0x%02hhx", hu->hdev->name, c);
+ BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u",
+ hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
+ H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
+ H5_HDR_LEN(hdr));
+
if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) {
BT_ERR("Invalid header checksum");
h5_reset_rx(h5);
return 0;
}
- if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_seq) {
+ if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) {
BT_ERR("Out-of-order packet arrived (%u != %u)",
- H5_HDR_SEQ(hdr), h5->tx_seq);
+ H5_HDR_SEQ(hdr), h5->tx_ack);
h5_reset_rx(h5);
return 0;
}
@@ -444,9 +506,10 @@ static void h5_slip_one_byte(struct sk_buff *skb, u8 c)
}
}
-static struct sk_buff *h5_build_pkt(struct h5 *h5, bool rel, u8 pkt_type,
+static struct sk_buff *h5_build_pkt(struct hci_uart *hu, bool rel, u8 pkt_type,
const u8 *data, size_t len)
{
+ struct h5 *h5 = hu->priv;
struct sk_buff *nskb;
u8 hdr[4];
int i;
@@ -465,7 +528,7 @@ static struct sk_buff *h5_build_pkt(struct h5 *h5, bool rel, u8 pkt_type,
h5_slip_delim(nskb);
- hdr[0] = h5->rx_seq << 3;
+ hdr[0] = h5->tx_ack << 3;
h5->tx_ack_req = false;
if (rel) {
@@ -478,6 +541,11 @@ static struct sk_buff *h5_build_pkt(struct h5 *h5, bool rel, u8 pkt_type,
hdr[2] = len >> 4;
hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff);
+ BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u",
+ hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
+ H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
+ H5_HDR_LEN(hdr));
+
for (i = 0; i < 4; i++)
h5_slip_one_byte(nskb, hdr[i]);
@@ -489,7 +557,7 @@ static struct sk_buff *h5_build_pkt(struct h5 *h5, bool rel, u8 pkt_type,
return nskb;
}
-static struct sk_buff *h5_prepare_pkt(struct h5 *h5, u8 pkt_type,
+static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type,
const u8 *data, size_t len)
{
bool rel;
@@ -509,13 +577,7 @@ static struct sk_buff *h5_prepare_pkt(struct h5 *h5, u8 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->tx_ack_req = false;
- return NULL;
+ return h5_build_pkt(hu, rel, pkt_type, data, len);
}
static struct sk_buff *h5_dequeue(struct hci_uart *hu)
@@ -525,7 +587,7 @@ 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, bt_cb(skb)->pkt_type,
+ nskb = h5_prepare_pkt(hu, bt_cb(skb)->pkt_type,
skb->data, skb->len);
if (nskb) {
kfree_skb(skb);
@@ -542,7 +604,7 @@ static struct sk_buff *h5_dequeue(struct hci_uart *hu)
goto unlock;
if ((skb = skb_dequeue(&h5->rel)) != NULL) {
- nskb = h5_prepare_pkt(h5, bt_cb(skb)->pkt_type,
+ nskb = h5_prepare_pkt(hu, bt_cb(skb)->pkt_type,
skb->data, skb->len);
if (nskb) {
__skb_queue_tail(&h5->unack, skb);
@@ -559,7 +621,7 @@ unlock:
spin_unlock_irqrestore(&h5->unack.lock, flags);
if (h5->tx_ack_req)
- return h5_prepare_ack(h5);
+ return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0);
return NULL;
}
--
1.7.10.4
--
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