Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 983 insertions, 0 deletions

diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
new file mode 100644
index 000000000..58f5504a3
--- /dev/null
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -0,0 +1,983 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *
+ *  Bluetooth HCI UART driver
+ *
+ *  Copyright (C) 2000-2001  Qualcomm Incorporated
+ *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
+ *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
+ */
+
+#include <linux/module.h>
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/interrupt.h>
+#include <linux/ptrace.h>
+#include <linux/poll.h>
+
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/signal.h>
+#include <linux/ioctl.h>
+#include <linux/skbuff.h>
+#include <linux/firmware.h>
+#include <linux/serdev.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#include "btintel.h"
+#include "btbcm.h"
+#include "hci_uart.h"
+
+#define VERSION "2.3"
+
+static const struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
+
+int hci_uart_register_proto(const struct hci_uart_proto *p)
+{
+	if (p->id >= HCI_UART_MAX_PROTO)
+		return -EINVAL;
+
+	if (hup[p->id])
+		return -EEXIST;
+
+	hup[p->id] = p;
+
+	BT_INFO("HCI UART protocol %s registered", p->name);
+
+	return 0;
+}
+
+int hci_uart_unregister_proto(const struct hci_uart_proto *p)
+{
+	if (p->id >= HCI_UART_MAX_PROTO)
+		return -EINVAL;
+
+	if (!hup[p->id])
+		return -EINVAL;
+
+	hup[p->id] = NULL;
+
+	return 0;
+}
+
+static const struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
+{
+	if (id >= HCI_UART_MAX_PROTO)
+		return NULL;
+
+	return hup[id];
+}
+
+static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
+{
+	struct hci_dev *hdev = hu->hdev;
+
+	/* Update HCI stat counters */
+	switch (pkt_type) {
+	case HCI_COMMAND_PKT:
+		hdev->stat.cmd_tx++;
+		break;
+
+	case HCI_ACLDATA_PKT:
+		hdev->stat.acl_tx++;
+		break;
+
+	case HCI_SCODATA_PKT:
+		hdev->stat.sco_tx++;
+		break;
+	}
+}
+
+static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
+{
+	struct sk_buff *skb = hu->tx_skb;
+
+	if (!skb) {
+		percpu_down_read(&hu->proto_lock);
+
+		if (test_bit(HCI_UART_PROTO_READY, &hu->flags) ||
+		    test_bit(HCI_UART_PROTO_INIT, &hu->flags))
+			skb = hu->proto->dequeue(hu);
+
+		percpu_up_read(&hu->proto_lock);
+	} else {
+		hu->tx_skb = NULL;
+	}
+
+	return skb;
+}
+
+int hci_uart_tx_wakeup(struct hci_uart *hu)
+{
+	/* This may be called in an IRQ context, so we can't sleep. Therefore
+	 * we try to acquire the lock only, and if that fails we assume the
+	 * tty is being closed because that is the only time the write lock is
+	 * acquired. If, however, at some point in the future the write lock
+	 * is also acquired in other situations, then this must be revisited.
+	 */
+	if (!percpu_down_read_trylock(&hu->proto_lock))
+		return 0;
+
+	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags) &&
+	    !test_bit(HCI_UART_PROTO_INIT, &hu->flags))
+		goto no_schedule;
+
+	set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
+	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state))
+		goto no_schedule;
+
+	BT_DBG("");
+
+	schedule_work(&hu->write_work);
+
+no_schedule:
+	percpu_up_read(&hu->proto_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hci_uart_tx_wakeup);
+
+static void hci_uart_write_work(struct work_struct *work)
+{
+	struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
+	struct tty_struct *tty = hu->tty;
+	struct hci_dev *hdev = hu->hdev;
+	struct sk_buff *skb;
+
+	/* REVISIT: should we cope with bad skbs or ->write() returning
+	 * and error value ?
+	 */
+
+restart:
+	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
+
+	while ((skb = hci_uart_dequeue(hu))) {
+		int len;
+
+		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
+		len = tty->ops->write(tty, skb->data, skb->len);
+		if (len < 0 || len > skb->len) {
+			hdev->stat.err_tx++;
+			kfree_skb(skb);
+			continue;
+		}
+
+		hdev->stat.byte_tx += len;
+
+		skb_pull(skb, len);
+		if (skb->len) {
+			hu->tx_skb = skb;
+			break;
+		}
+
+		hci_uart_tx_complete(hu, hci_skb_pkt_type(skb));
+		kfree_skb(skb);
+	}
+
+	clear_bit(HCI_UART_SENDING, &hu->tx_state);
+	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
+		goto restart;
+
+	wake_up_bit(&hu->tx_state, HCI_UART_SENDING);
+}
+
+void hci_uart_init_work(struct work_struct *work)
+{
+	struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
+	int err;
+	struct hci_dev *hdev;
+
+	if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
+		return;
+
+	err = hci_register_dev(hu->hdev);
+	if (err < 0) {
+		BT_ERR("Can't register HCI device");
+
+		percpu_down_write(&hu->proto_lock);
+		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
+		percpu_up_write(&hu->proto_lock);
+
+		/* Safely cancel work after clearing flags */
+		cancel_work_sync(&hu->write_work);
+
+		/* Close protocol before freeing hdev */
+		hu->proto->close(hu);
+		hdev = hu->hdev;
+		hu->hdev = NULL;
+		hci_free_dev(hdev);
+		return;
+	}
+
+	set_bit(HCI_UART_REGISTERED, &hu->flags);
+}
+
+int hci_uart_init_ready(struct hci_uart *hu)
+{
+	if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
+		return -EALREADY;
+
+	schedule_work(&hu->init_ready);
+
+	return 0;
+}
+
+int hci_uart_wait_until_sent(struct hci_uart *hu)
+{
+	return wait_on_bit_timeout(&hu->tx_state, HCI_UART_SENDING,
+				   TASK_INTERRUPTIBLE,
+				   msecs_to_jiffies(2000));
+}
+
+/* ------- Interface to HCI layer ------ */
+/* Reset device */
+static int hci_uart_flush(struct hci_dev *hdev)
+{
+	struct hci_uart *hu  = hci_get_drvdata(hdev);
+	struct tty_struct *tty = hu->tty;
+
+	BT_DBG("hdev %p tty %p", hdev, tty);
+
+	disable_work_sync(&hu->write_work);
+
+	if (hu->tx_skb) {
+		kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
+	}
+
+	/* Flush any pending characters in the driver and discipline. */
+	tty_ldisc_flush(tty);
+	tty_driver_flush_buffer(tty);
+
+	percpu_down_read(&hu->proto_lock);
+
+	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
+		hu->proto->flush(hu);
+
+	percpu_up_read(&hu->proto_lock);
+
+	/* Resume TX. Also reschedule in case work was queued concurrently;
+	 * this may schedule write_work although there's nothing to do.
+	 */
+	enable_work(&hu->write_work);
+	clear_bit(HCI_UART_SENDING, &hu->tx_state);
+	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
+		hci_uart_tx_wakeup(hu);
+
+	return 0;
+}
+
+/* Initialize device */
+static int hci_uart_open(struct hci_dev *hdev)
+{
+	BT_DBG("%s %p", hdev->name, hdev);
+
+	/* Undo clearing this from hci_uart_close() */
+	hdev->flush = hci_uart_flush;
+
+	return 0;
+}
+
+/* Close device */
+static int hci_uart_close(struct hci_dev *hdev)
+{
+	BT_DBG("hdev %p", hdev);
+
+	hci_uart_flush(hdev);
+	hdev->flush = NULL;
+	return 0;
+}
+
+/* Send frames from HCI layer */
+static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
+{
+	struct hci_uart *hu = hci_get_drvdata(hdev);
+
+	BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
+	       skb->len);
+
+	percpu_down_read(&hu->proto_lock);
+
+	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags) &&
+	    !test_bit(HCI_UART_PROTO_INIT, &hu->flags)) {
+		percpu_up_read(&hu->proto_lock);
+		return -EUNATCH;
+	}
+
+	hu->proto->enqueue(hu, skb);
+	percpu_up_read(&hu->proto_lock);
+
+	hci_uart_tx_wakeup(hu);
+
+	return 0;
+}
+
+/* Check the underlying device or tty has flow control support */
+bool hci_uart_has_flow_control(struct hci_uart *hu)
+{
+	/* serdev nodes check if the needed operations are present */
+	if (hu->serdev)
+		return true;
+
+	if (hu->tty->driver->ops->tiocmget && hu->tty->driver->ops->tiocmset)
+		return true;
+
+	return false;
+}
+
+/* Flow control or un-flow control the device */
+void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
+{
+	struct tty_struct *tty = hu->tty;
+	struct ktermios ktermios;
+	int status;
+	unsigned int set = 0;
+	unsigned int clear = 0;
+
+	if (hu->serdev) {
+		serdev_device_set_flow_control(hu->serdev, !enable);
+		serdev_device_set_rts(hu->serdev, !enable);
+		return;
+	}
+
+	if (enable) {
+		/* Disable hardware flow control */
+		ktermios = tty->termios;
+		ktermios.c_cflag &= ~CRTSCTS;
+		tty_set_termios(tty, &ktermios);
+		BT_DBG("Disabling hardware flow control: %s",
+		       (tty->termios.c_cflag & CRTSCTS) ? "failed" : "success");
+
+		/* Clear RTS to prevent the device from sending */
+		/* Most UARTs need OUT2 to enable interrupts */
+		status = tty->driver->ops->tiocmget(tty);
+		BT_DBG("Current tiocm 0x%x", status);
+
+		set &= ~(TIOCM_OUT2 | TIOCM_RTS);
+		clear = ~set;
+		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
+		       TIOCM_OUT2 | TIOCM_LOOP;
+		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
+			 TIOCM_OUT2 | TIOCM_LOOP;
+		status = tty->driver->ops->tiocmset(tty, set, clear);
+		BT_DBG("Clearing RTS: %s", status ? "failed" : "success");
+	} else {
+		/* Set RTS to allow the device to send again */
+		status = tty->driver->ops->tiocmget(tty);
+		BT_DBG("Current tiocm 0x%x", status);
+
+		set |= (TIOCM_OUT2 | TIOCM_RTS);
+		clear = ~set;
+		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
+		       TIOCM_OUT2 | TIOCM_LOOP;
+		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
+			 TIOCM_OUT2 | TIOCM_LOOP;
+		status = tty->driver->ops->tiocmset(tty, set, clear);
+		BT_DBG("Setting RTS: %s", status ? "failed" : "success");
+
+		/* Re-enable hardware flow control */
+		ktermios = tty->termios;
+		ktermios.c_cflag |= CRTSCTS;
+		tty_set_termios(tty, &ktermios);
+		BT_DBG("Enabling hardware flow control: %s",
+		       !(tty->termios.c_cflag & CRTSCTS) ? "failed" : "success");
+	}
+}
+
+void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
+			 unsigned int oper_speed)
+{
+	hu->init_speed = init_speed;
+	hu->oper_speed = oper_speed;
+}
+
+void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
+{
+	struct tty_struct *tty = hu->tty;
+	struct ktermios ktermios;
+
+	ktermios = tty->termios;
+	ktermios.c_cflag &= ~CBAUD;
+	tty_termios_encode_baud_rate(&ktermios, speed, speed);
+
+	/* tty_set_termios() return not checked as it is always 0 */
+	tty_set_termios(tty, &ktermios);
+
+	BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
+	       tty->termios.c_ispeed, tty->termios.c_ospeed);
+}
+
+static int hci_uart_setup(struct hci_dev *hdev)
+{
+	struct hci_uart *hu = hci_get_drvdata(hdev);
+	struct hci_rp_read_local_version *ver;
+	struct sk_buff *skb;
+	unsigned int speed;
+	int err;
+
+	/* Init speed if any */
+	if (hu->init_speed)
+		speed = hu->init_speed;
+	else if (hu->proto->init_speed)
+		speed = hu->proto->init_speed;
+	else
+		speed = 0;
+
+	if (speed)
+		hci_uart_set_baudrate(hu, speed);
+
+	/* Operational speed if any */
+	if (hu->oper_speed)
+		speed = hu->oper_speed;
+	else if (hu->proto->oper_speed)
+		speed = hu->proto->oper_speed;
+	else
+		speed = 0;
+
+	if (hu->proto->set_baudrate && speed) {
+		err = hu->proto->set_baudrate(hu, speed);
+		if (!err)
+			hci_uart_set_baudrate(hu, speed);
+	}
+
+	if (hu->proto->setup)
+		return hu->proto->setup(hu);
+
+	if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
+		return 0;
+
+	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
+			     HCI_INIT_TIMEOUT);
+	if (IS_ERR(skb)) {
+		BT_ERR("%s: Reading local version information failed (%ld)",
+		       hdev->name, PTR_ERR(skb));
+		return 0;
+	}
+
+	if (skb->len != sizeof(*ver)) {
+		BT_ERR("%s: Event length mismatch for version information",
+		       hdev->name);
+		goto done;
+	}
+
+	ver = (struct hci_rp_read_local_version *)skb->data;
+
+	switch (le16_to_cpu(ver->manufacturer)) {
+#ifdef CONFIG_BT_HCIUART_INTEL
+	case 2:
+		hdev->set_bdaddr = btintel_set_bdaddr;
+		btintel_check_bdaddr(hdev);
+		break;
+#endif
+#ifdef CONFIG_BT_HCIUART_BCM
+	case 15:
+		hdev->set_bdaddr = btbcm_set_bdaddr;
+		btbcm_check_bdaddr(hdev);
+		break;
+#endif
+	default:
+		break;
+	}
+
+done:
+	kfree_skb(skb);
+	return 0;
+}
+
+/* ------ LDISC part ------ */
+/* hci_uart_tty_open
+ *
+ *     Called when line discipline changed to HCI_UART.
+ *
+ * Arguments:
+ *     tty    pointer to tty info structure
+ * Return Value:
+ *     0 if success, otherwise error code
+ */
+static int hci_uart_tty_open(struct tty_struct *tty)
+{
+	struct hci_uart *hu;
+
+	BT_DBG("tty %p", tty);
+
+	if (!capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	/* Error if the tty has no write op instead of leaving an exploitable
+	 * hole
+	 */
+	if (tty->ops->write == NULL)
+		return -EOPNOTSUPP;
+
+	hu = kzalloc_obj(*hu);
+	if (!hu) {
+		BT_ERR("Can't allocate control structure");
+		return -ENFILE;
+	}
+	if (percpu_init_rwsem(&hu->proto_lock)) {
+		BT_ERR("Can't allocate semaphore structure");
+		kfree(hu);
+		return -ENOMEM;
+	}
+
+	tty->disc_data = hu;
+	hu->tty = tty;
+	tty->receive_room = 65536;
+
+	/* disable alignment support by default */
+	hu->alignment = 1;
+	hu->padding = 0;
+
+	/* Use serial port speed as oper_speed */
+	hu->oper_speed = tty->termios.c_ospeed;
+
+	INIT_WORK(&hu->init_ready, hci_uart_init_work);
+	INIT_WORK(&hu->write_work, hci_uart_write_work);
+
+	/* Flush any pending characters in the driver */
+	tty_driver_flush_buffer(tty);
+
+	return 0;
+}
+
+/* hci_uart_tty_close()
+ *
+ *    Called when the line discipline is changed to something
+ *    else, the tty is closed, or the tty detects a hangup.
+ */
+static void hci_uart_tty_close(struct tty_struct *tty)
+{
+	struct hci_uart *hu = tty->disc_data;
+	struct hci_dev *hdev;
+	bool proto_ready;
+
+	BT_DBG("tty %p", tty);
+
+	/* Detach from the tty */
+	tty->disc_data = NULL;
+
+	if (!hu)
+		return;
+
+	/* Wait for init_ready to finish to prevent registration races */
+	cancel_work_sync(&hu->init_ready);
+
+	proto_ready = test_bit(HCI_UART_PROTO_READY, &hu->flags);
+	if (proto_ready) {
+		percpu_down_write(&hu->proto_lock);
+		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
+		percpu_up_write(&hu->proto_lock);
+	}
+
+	/*
+	 * Unconditionally cancel write_work AFTER clearing PROTO_READY.
+	 * This ensures that concurrent protocol timers cannot requeue
+	 * write_work via hci_uart_tx_wakeup(), permanently preventing
+	 * double-free races and UAFs.
+	 */
+	cancel_work_sync(&hu->write_work);
+
+	hdev = hu->hdev;
+	if (hdev)
+		hci_uart_close(hdev); /* proto->flush is safely skipped */
+
+	if (proto_ready) {
+		if (hdev) {
+			if (test_bit(HCI_UART_REGISTERED, &hu->flags))
+				hci_unregister_dev(hdev);
+		}
+		/* Close protocol before freeing hdev (intrinsically purges queues) */
+		hu->proto->close(hu);
+
+		if (hdev)
+			hci_free_dev(hdev);
+	}
+	clear_bit(HCI_UART_PROTO_SET, &hu->flags);
+
+	percpu_free_rwsem(&hu->proto_lock);
+
+	kfree(hu);
+}
+
+/* hci_uart_tty_wakeup()
+ *
+ *    Callback for transmit wakeup. Called when low level
+ *    device driver can accept more send data.
+ *
+ * Arguments:        tty    pointer to associated tty instance data
+ * Return Value:    None
+ */
+static void hci_uart_tty_wakeup(struct tty_struct *tty)
+{
+	struct hci_uart *hu = tty->disc_data;
+
+	BT_DBG("");
+
+	if (!hu)
+		return;
+
+	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
+
+	if (tty != hu->tty)
+		return;
+
+	if (test_bit(HCI_UART_PROTO_READY, &hu->flags) ||
+	    test_bit(HCI_UART_PROTO_INIT, &hu->flags))
+		hci_uart_tx_wakeup(hu);
+}
+
+/* hci_uart_tty_receive()
+ *
+ *     Called by tty low level driver when receive data is
+ *     available.
+ *
+ * Arguments:  tty          pointer to tty instance data
+ *             data         pointer to received data
+ *             flags        pointer to flags for data
+ *             count        count of received data in bytes
+ *
+ * Return Value:    None
+ */
+static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
+				 const u8 *flags, size_t count)
+{
+	struct hci_uart *hu = tty->disc_data;
+
+	if (!hu || tty != hu->tty)
+		return;
+
+	percpu_down_read(&hu->proto_lock);
+
+	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags) &&
+	    !test_bit(HCI_UART_PROTO_INIT, &hu->flags)) {
+		percpu_up_read(&hu->proto_lock);
+		return;
+	}
+
+	/* It does not need a lock here as it is already protected by a mutex in
+	 * tty caller
+	 */
+	hu->proto->recv(hu, data, count);
+
+	if (hu->hdev)
+		hu->hdev->stat.byte_rx += count;
+
+	percpu_up_read(&hu->proto_lock);
+
+	tty_unthrottle(tty);
+}
+
+static int hci_uart_register_dev(struct hci_uart *hu)
+{
+	struct hci_dev *hdev;
+	int err;
+
+	BT_DBG("");
+
+	/* Initialize and register HCI device */
+	hdev = hci_alloc_dev();
+	if (!hdev) {
+		BT_ERR("Can't allocate HCI device");
+		return -ENOMEM;
+	}
+
+	hu->hdev = hdev;
+
+	hdev->bus = HCI_UART;
+	hci_set_drvdata(hdev, hu);
+
+	/* Only when vendor specific setup callback is provided, consider
+	 * the manufacturer information valid. This avoids filling in the
+	 * value for Ericsson when nothing is specified.
+	 */
+	if (hu->proto->setup)
+		hdev->manufacturer = hu->proto->manufacturer;
+
+	hdev->open  = hci_uart_open;
+	hdev->close = hci_uart_close;
+	hdev->flush = hci_uart_flush;
+	hdev->send  = hci_uart_send_frame;
+	hdev->setup = hci_uart_setup;
+	SET_HCIDEV_DEV(hdev, hu->tty->dev);
+
+	if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
+		hci_set_quirk(hdev, HCI_QUIRK_RAW_DEVICE);
+
+	if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
+		hci_set_quirk(hdev, HCI_QUIRK_EXTERNAL_CONFIG);
+
+	if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
+		hci_set_quirk(hdev, HCI_QUIRK_RESET_ON_CLOSE);
+
+	/* Only call open() for the protocol after hdev is fully initialized as
+	 * open() (or a timer/workqueue it starts) may attempt to reference it.
+	 */
+	err = hu->proto->open(hu);
+	if (err) {
+		hu->hdev = NULL;
+		hci_free_dev(hdev);
+		return err;
+	}
+
+	set_bit(HCI_UART_PROTO_INIT, &hu->flags);
+
+	if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
+		return 0;
+
+	if (hci_register_dev(hdev) < 0) {
+		BT_ERR("Can't register HCI device");
+		percpu_down_write(&hu->proto_lock);
+		clear_bit(HCI_UART_PROTO_INIT, &hu->flags);
+		percpu_up_write(&hu->proto_lock);
+		/* Cancel work after clearing flags */
+		cancel_work_sync(&hu->write_work);
+
+		/* Close protocol before freeing hdev */
+		hu->proto->close(hu);
+		hu->hdev = NULL;
+		hci_free_dev(hdev);
+		return -ENODEV;
+	}
+
+	set_bit(HCI_UART_REGISTERED, &hu->flags);
+
+	return 0;
+}
+
+static int hci_uart_set_proto(struct hci_uart *hu, int id)
+{
+	const struct hci_uart_proto *p;
+	int err;
+
+	p = hci_uart_get_proto(id);
+	if (!p)
+		return -EPROTONOSUPPORT;
+
+	hu->proto = p;
+
+	err = hci_uart_register_dev(hu);
+	if (err)
+		return err;
+
+
+	set_bit(HCI_UART_PROTO_READY, &hu->flags);
+	clear_bit(HCI_UART_PROTO_INIT, &hu->flags);
+
+	return 0;
+}
+
+static int hci_uart_set_flags(struct hci_uart *hu, unsigned long flags)
+{
+	unsigned long valid_flags = BIT(HCI_UART_RAW_DEVICE) |
+				    BIT(HCI_UART_RESET_ON_INIT) |
+				    BIT(HCI_UART_INIT_PENDING) |
+				    BIT(HCI_UART_EXT_CONFIG) |
+				    BIT(HCI_UART_VND_DETECT);
+
+	if (flags & ~valid_flags)
+		return -EINVAL;
+
+	hu->hdev_flags = flags;
+
+	return 0;
+}
+
+/* hci_uart_tty_ioctl()
+ *
+ *    Process IOCTL system call for the tty device.
+ *
+ * Arguments:
+ *
+ *    tty        pointer to tty instance data
+ *    cmd        IOCTL command code
+ *    arg        argument for IOCTL call (cmd dependent)
+ *
+ * Return Value:    Command dependent
+ */
+static int hci_uart_tty_ioctl(struct tty_struct *tty, unsigned int cmd,
+			      unsigned long arg)
+{
+	struct hci_uart *hu = tty->disc_data;
+	int err = 0;
+
+	BT_DBG("");
+
+	/* Verify the status of the device */
+	if (!hu)
+		return -EBADF;
+
+	switch (cmd) {
+	case HCIUARTSETPROTO:
+		if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
+			err = hci_uart_set_proto(hu, arg);
+			if (err)
+				clear_bit(HCI_UART_PROTO_SET, &hu->flags);
+		} else
+			err = -EBUSY;
+		break;
+
+	case HCIUARTGETPROTO:
+		if (test_bit(HCI_UART_PROTO_SET, &hu->flags) &&
+		    test_bit(HCI_UART_PROTO_READY, &hu->flags))
+			err = hu->proto->id;
+		else
+			err = -EUNATCH;
+		break;
+
+	case HCIUARTGETDEVICE:
+		if (test_bit(HCI_UART_REGISTERED, &hu->flags))
+			err = hu->hdev->id;
+		else
+			err = -EUNATCH;
+		break;
+
+	case HCIUARTSETFLAGS:
+		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
+			err = -EBUSY;
+		else
+			err = hci_uart_set_flags(hu, arg);
+		break;
+
+	case HCIUARTGETFLAGS:
+		err = hu->hdev_flags;
+		break;
+
+	default:
+		err = n_tty_ioctl_helper(tty, cmd, arg);
+		break;
+	}
+
+	return err;
+}
+
+/*
+ * We don't provide read/write/poll interface for user space.
+ */
+static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
+				 u8 *buf, size_t nr, void **cookie,
+				 unsigned long offset)
+{
+	return 0;
+}
+
+static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
+				  const u8 *data, size_t count)
+{
+	return 0;
+}
+
+static struct tty_ldisc_ops hci_uart_ldisc = {
+	.owner		= THIS_MODULE,
+	.num		= N_HCI,
+	.name		= "n_hci",
+	.open		= hci_uart_tty_open,
+	.close		= hci_uart_tty_close,
+	.read		= hci_uart_tty_read,
+	.write		= hci_uart_tty_write,
+	.ioctl		= hci_uart_tty_ioctl,
+	.compat_ioctl	= hci_uart_tty_ioctl,
+	.receive_buf	= hci_uart_tty_receive,
+	.write_wakeup	= hci_uart_tty_wakeup,
+};
+
+static int __init hci_uart_init(void)
+{
+	int err;
+
+	BT_INFO("HCI UART driver ver %s", VERSION);
+
+	/* Register the tty discipline */
+	err = tty_register_ldisc(&hci_uart_ldisc);
+	if (err) {
+		BT_ERR("HCI line discipline registration failed. (%d)", err);
+		return err;
+	}
+
+#ifdef CONFIG_BT_HCIUART_H4
+	h4_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_BCSP
+	bcsp_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_LL
+	ll_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_ATH3K
+	ath_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_3WIRE
+	h5_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_INTEL
+	intel_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_BCM
+	bcm_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_QCA
+	qca_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_AG6XX
+	ag6xx_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_MRVL
+	mrvl_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_AML
+	aml_init();
+#endif
+	return 0;
+}
+
+static void __exit hci_uart_exit(void)
+{
+#ifdef CONFIG_BT_HCIUART_H4
+	h4_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_BCSP
+	bcsp_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_LL
+	ll_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_ATH3K
+	ath_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_3WIRE
+	h5_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_INTEL
+	intel_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_BCM
+	bcm_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_QCA
+	qca_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_AG6XX
+	ag6xx_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_MRVL
+	mrvl_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_AML
+	aml_deinit();
+#endif
+	tty_unregister_ldisc(&hci_uart_ldisc);
+}
+
+module_init(hci_uart_init);
+module_exit(hci_uart_exit);
+
+MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
+MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
+MODULE_VERSION(VERSION);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_LDISC(N_HCI);