v4.19.13 snapshot.
diff --git a/drivers/bluetooth/hci_ath.c b/drivers/bluetooth/hci_ath.c
new file mode 100644
index 0000000..d568fbd
--- /dev/null
+++ b/drivers/bluetooth/hci_ath.c
@@ -0,0 +1,279 @@
+/*
+ *  Atheros Communication Bluetooth HCIATH3K UART protocol
+ *
+ *  HCIATH3K (HCI Atheros AR300x Protocol) is a Atheros Communication's
+ *  power management protocol extension to H4 to support AR300x Bluetooth Chip.
+ *
+ *  Copyright (c) 2009-2010 Atheros Communications Inc.
+ *
+ *  Acknowledgements:
+ *  This file is based on hci_h4.c, which was written
+ *  by Maxim Krasnyansky and Marcel Holtmann.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/errno.h>
+#include <linux/ioctl.h>
+#include <linux/skbuff.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#include "hci_uart.h"
+
+struct ath_struct {
+	struct hci_uart *hu;
+	unsigned int cur_sleep;
+
+	struct sk_buff *rx_skb;
+	struct sk_buff_head txq;
+	struct work_struct ctxtsw;
+};
+
+#define OP_WRITE_TAG	0x01
+
+#define INDEX_BDADDR	0x01
+
+struct ath_vendor_cmd {
+	__u8 opcode;
+	__le16 index;
+	__u8 len;
+	__u8 data[251];
+} __packed;
+
+static int ath_wakeup_ar3k(struct tty_struct *tty)
+{
+	int status = tty->driver->ops->tiocmget(tty);
+
+	if (status & TIOCM_CTS)
+		return status;
+
+	/* Clear RTS first */
+	tty->driver->ops->tiocmget(tty);
+	tty->driver->ops->tiocmset(tty, 0x00, TIOCM_RTS);
+	msleep(20);
+
+	/* Set RTS, wake up board */
+	tty->driver->ops->tiocmget(tty);
+	tty->driver->ops->tiocmset(tty, TIOCM_RTS, 0x00);
+	msleep(20);
+
+	status = tty->driver->ops->tiocmget(tty);
+	return status;
+}
+
+static void ath_hci_uart_work(struct work_struct *work)
+{
+	int status;
+	struct ath_struct *ath;
+	struct hci_uart *hu;
+	struct tty_struct *tty;
+
+	ath = container_of(work, struct ath_struct, ctxtsw);
+
+	hu = ath->hu;
+	tty = hu->tty;
+
+	/* verify and wake up controller */
+	if (ath->cur_sleep) {
+		status = ath_wakeup_ar3k(tty);
+		if (!(status & TIOCM_CTS))
+			return;
+	}
+
+	/* Ready to send Data */
+	clear_bit(HCI_UART_SENDING, &hu->tx_state);
+	hci_uart_tx_wakeup(hu);
+}
+
+static int ath_open(struct hci_uart *hu)
+{
+	struct ath_struct *ath;
+
+	BT_DBG("hu %p", hu);
+
+	ath = kzalloc(sizeof(*ath), GFP_KERNEL);
+	if (!ath)
+		return -ENOMEM;
+
+	skb_queue_head_init(&ath->txq);
+
+	hu->priv = ath;
+	ath->hu = hu;
+
+	INIT_WORK(&ath->ctxtsw, ath_hci_uart_work);
+
+	return 0;
+}
+
+static int ath_close(struct hci_uart *hu)
+{
+	struct ath_struct *ath = hu->priv;
+
+	BT_DBG("hu %p", hu);
+
+	skb_queue_purge(&ath->txq);
+
+	kfree_skb(ath->rx_skb);
+
+	cancel_work_sync(&ath->ctxtsw);
+
+	hu->priv = NULL;
+	kfree(ath);
+
+	return 0;
+}
+
+static int ath_flush(struct hci_uart *hu)
+{
+	struct ath_struct *ath = hu->priv;
+
+	BT_DBG("hu %p", hu);
+
+	skb_queue_purge(&ath->txq);
+
+	return 0;
+}
+
+static int ath_vendor_cmd(struct hci_dev *hdev, uint8_t opcode, uint16_t index,
+			  const void *data, size_t dlen)
+{
+	struct sk_buff *skb;
+	struct ath_vendor_cmd cmd;
+
+	if (dlen > sizeof(cmd.data))
+		return -EINVAL;
+
+	cmd.opcode = opcode;
+	cmd.index = cpu_to_le16(index);
+	cmd.len = dlen;
+	memcpy(cmd.data, data, dlen);
+
+	skb = __hci_cmd_sync(hdev, 0xfc0b, dlen + 4, &cmd, HCI_INIT_TIMEOUT);
+	if (IS_ERR(skb))
+		return PTR_ERR(skb);
+	kfree_skb(skb);
+
+	return 0;
+}
+
+static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
+{
+	return ath_vendor_cmd(hdev, OP_WRITE_TAG, INDEX_BDADDR, bdaddr,
+			      sizeof(*bdaddr));
+}
+
+static int ath_setup(struct hci_uart *hu)
+{
+	BT_DBG("hu %p", hu);
+
+	hu->hdev->set_bdaddr = ath_set_bdaddr;
+
+	return 0;
+}
+
+static const struct h4_recv_pkt ath_recv_pkts[] = {
+	{ H4_RECV_ACL,   .recv = hci_recv_frame },
+	{ H4_RECV_SCO,   .recv = hci_recv_frame },
+	{ H4_RECV_EVENT, .recv = hci_recv_frame },
+};
+
+static int ath_recv(struct hci_uart *hu, const void *data, int count)
+{
+	struct ath_struct *ath = hu->priv;
+
+	ath->rx_skb = h4_recv_buf(hu->hdev, ath->rx_skb, data, count,
+				  ath_recv_pkts, ARRAY_SIZE(ath_recv_pkts));
+	if (IS_ERR(ath->rx_skb)) {
+		int err = PTR_ERR(ath->rx_skb);
+		bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
+		ath->rx_skb = NULL;
+		return err;
+	}
+
+	return count;
+}
+
+#define HCI_OP_ATH_SLEEP 0xFC04
+
+static int ath_enqueue(struct hci_uart *hu, struct sk_buff *skb)
+{
+	struct ath_struct *ath = hu->priv;
+
+	if (hci_skb_pkt_type(skb) == HCI_SCODATA_PKT) {
+		kfree_skb(skb);
+		return 0;
+	}
+
+	/* Update power management enable flag with parameters of
+	 * HCI sleep enable vendor specific HCI command.
+	 */
+	if (hci_skb_pkt_type(skb) == HCI_COMMAND_PKT) {
+		struct hci_command_hdr *hdr = (void *)skb->data;
+
+		if (__le16_to_cpu(hdr->opcode) == HCI_OP_ATH_SLEEP)
+			ath->cur_sleep = skb->data[HCI_COMMAND_HDR_SIZE];
+	}
+
+	BT_DBG("hu %p skb %p", hu, skb);
+
+	/* Prepend skb with frame type */
+	memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
+
+	skb_queue_tail(&ath->txq, skb);
+	set_bit(HCI_UART_SENDING, &hu->tx_state);
+
+	schedule_work(&ath->ctxtsw);
+
+	return 0;
+}
+
+static struct sk_buff *ath_dequeue(struct hci_uart *hu)
+{
+	struct ath_struct *ath = hu->priv;
+
+	return skb_dequeue(&ath->txq);
+}
+
+static const struct hci_uart_proto athp = {
+	.id		= HCI_UART_ATH3K,
+	.name		= "ATH3K",
+	.manufacturer	= 69,
+	.open		= ath_open,
+	.close		= ath_close,
+	.flush		= ath_flush,
+	.setup		= ath_setup,
+	.recv		= ath_recv,
+	.enqueue	= ath_enqueue,
+	.dequeue	= ath_dequeue,
+};
+
+int __init ath_init(void)
+{
+	return hci_uart_register_proto(&athp);
+}
+
+int __exit ath_deinit(void)
+{
+	return hci_uart_unregister_proto(&athp);
+}