Bluetooth: Initial skeleton for Three-wire UART (H5) support

This patch adds the initial skeleton for Three-wire UART (H5) support
and hooks it up to the HCI UART framework.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>

drivers/bluetooth/Kconfig

@@ -81,6 +81,18 @@ config BT_HCIUART_LL
 
 	  Say Y here to compile support for HCILL protocol.
 
+config BT_HCIUART_3WIRE
+	bool "Three-wire UART (H5) protocol support"
+	depends on BT_HCIUART
+	help
+	  The HCI Three-wire UART Transport Layer makes it possible to
+	  user the Bluetooth HCI over a serial port interface. The HCI
+	  Three-wire UART Transport Layer assumes that the UART
+	  communication may have bit errors, overrun errors or burst
+	  errors and thereby making CTS/RTS lines unnecessary.
+
+	  Say Y here to compile support for Three-wire UART protocol.
+
 config BT_HCIBCM203X
 	tristate "HCI BCM203x USB driver"
 	depends on USB

drivers/bluetooth/Makefile

@@ -28,4 +28,5 @@ hci_uart-$(CONFIG_BT_HCIUART_H4)	+= hci_h4.o
 hci_uart-$(CONFIG_BT_HCIUART_BCSP)	+= hci_bcsp.o
 hci_uart-$(CONFIG_BT_HCIUART_LL)	+= hci_ll.o
 hci_uart-$(CONFIG_BT_HCIUART_ATH3K)	+= hci_ath.o
+hci_uart-$(CONFIG_BT_HCIUART_3WIRE)	+= hci_h5.o
 hci_uart-objs				:= $(hci_uart-y)

drivers/bluetooth/hci_h5.c

@@ -0,0 +1,88 @@
+/*
+ *
+ *  Bluetooth HCI Three-wire UART driver
+ *
+ *  Copyright (C) 2012  Intel Corporation
+ *
+ *
+ *  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/kernel.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#include "hci_uart.h"
+
+static int h5_open(struct hci_uart *hu)
+{
+	return -ENOSYS;
+}
+
+static int h5_close(struct hci_uart *hu)
+{
+	return -ENOSYS;
+}
+
+static int h5_recv(struct hci_uart *hu, void *data, int count)
+{
+	return -ENOSYS;
+}
+
+static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb)
+{
+	return -ENOSYS;
+}
+
+static struct sk_buff *h5_dequeue(struct hci_uart *hu)
+{
+	return NULL;
+}
+
+static int h5_flush(struct hci_uart *hu)
+{
+	return -ENOSYS;
+}
+
+static struct hci_uart_proto h5p = {
+	.id		= HCI_UART_3WIRE,
+	.open		= h5_open,
+	.close		= h5_close,
+	.recv		= h5_recv,
+	.enqueue	= h5_enqueue,
+	.dequeue	= h5_dequeue,
+	.flush		= h5_flush,
+};
+
+int __init h5_init(void)
+{
+	int err = hci_uart_register_proto(&h5p);
+
+	if (!err)
+		BT_INFO("HCI Three-wire UART (H5) protocol initialized");
+	else
+		BT_ERR("HCI Three-wire UART (H5) protocol init failed");
+
+	return err;
+}
+
+int __exit h5_deinit(void)
+{
+	return hci_uart_unregister_proto(&h5p);
+}

drivers/bluetooth/hci_ldisc.c

@@ -558,6 +558,9 @@ static int __init hci_uart_init(void)
 #ifdef CONFIG_BT_HCIUART_ATH3K
 	ath_init();
 #endif
+#ifdef CONFIG_BT_HCIUART_3WIRE
+	h5_init();
+#endif
 
 	return 0;
 }
@@ -578,6 +581,9 @@ static void __exit hci_uart_exit(void)
 #ifdef CONFIG_BT_HCIUART_ATH3K
 	ath_deinit();
 #endif
+#ifdef CONFIG_BT_HCIUART_3WIRE
+	h5_deinit();
+#endif
 
 	/* Release tty registration of line discipline */
 	if ((err = tty_unregister_ldisc(N_HCI)))

drivers/bluetooth/hci_uart.h

@@ -104,3 +104,8 @@ int ll_deinit(void);
 int ath_init(void);
 int ath_deinit(void);
 #endif
+
+#ifdef CONFIG_BT_HCIUART_3WIRE
+int h5_init(void);
+int h5_deinit(void);
+#endif