Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 839 insertions, 0 deletions

diff --git a/drivers/usb/serial/oti6858.c b/drivers/usb/serial/oti6858.c
new file mode 100644
index 000000000..c6364e8ff
--- /dev/null
+++ b/drivers/usb/serial/oti6858.c
@@ -0,0 +1,839 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Ours Technology Inc. OTi-6858 USB to serial adapter driver.
+ *
+ * Copyleft  (C) 2007 Kees Lemmens (adapted for kernel 2.6.20)
+ * Copyright (C) 2006 Tomasz Michal Lukaszewski (FIXME: add e-mail)
+ * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
+ * Copyright (C) 2003 IBM Corp.
+ *
+ * Many thanks to the authors of pl2303 driver: all functions in this file
+ * are heavily based on pl2303 code, buffering code is a 1-to-1 copy.
+ *
+ * Warning! You use this driver on your own risk! The only official
+ * description of this device I have is datasheet from manufacturer,
+ * and it doesn't contain almost any information needed to write a driver.
+ * Almost all knowlegde used while writing this driver was gathered by:
+ *  - analyzing traffic between device and the M$ Windows 2000 driver,
+ *  - trying different bit combinations and checking pin states
+ *    with a voltmeter,
+ *  - receiving malformed frames and producing buffer overflows
+ *    to learn how errors are reported,
+ * So, THIS CODE CAN DESTROY OTi-6858 AND ANY OTHER DEVICES, THAT ARE
+ * CONNECTED TO IT!
+ *
+ * See Documentation/usb/usb-serial.rst for more information on using this
+ * driver
+ *
+ * TODO:
+ *  - implement correct flushing for ioctls and oti6858_close()
+ *  - check how errors (rx overflow, parity error, framing error) are reported
+ *  - implement oti6858_break_ctl()
+ *  - implement more ioctls
+ *  - test/implement flow control
+ *  - allow setting custom baud rates
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/usb.h>
+#include <linux/usb/serial.h>
+#include <linux/kfifo.h>
+#include "oti6858.h"
+
+#define OTI6858_DESCRIPTION \
+	"Ours Technology Inc. OTi-6858 USB to serial adapter driver"
+#define OTI6858_AUTHOR "Tomasz Michal Lukaszewski <FIXME@FIXME>"
+
+static const struct usb_device_id id_table[] = {
+	{ USB_DEVICE(OTI6858_VENDOR_ID, OTI6858_PRODUCT_ID) },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(usb, id_table);
+
+/* requests */
+#define	OTI6858_REQ_GET_STATUS		(USB_DIR_IN | USB_TYPE_VENDOR | 0x00)
+#define	OTI6858_REQ_T_GET_STATUS	0x01
+
+#define	OTI6858_REQ_SET_LINE		(USB_DIR_OUT | USB_TYPE_VENDOR | 0x00)
+#define	OTI6858_REQ_T_SET_LINE		0x00
+
+#define	OTI6858_REQ_CHECK_TXBUFF	(USB_DIR_IN | USB_TYPE_VENDOR | 0x01)
+#define	OTI6858_REQ_T_CHECK_TXBUFF	0x00
+
+/* format of the control packet */
+struct oti6858_control_pkt {
+	__le16	divisor;	/* baud rate = 96000000 / (16 * divisor), LE */
+#define OTI6858_MAX_BAUD_RATE	3000000
+	u8	frame_fmt;
+#define FMT_STOP_BITS_MASK	0xc0
+#define FMT_STOP_BITS_1		0x00
+#define FMT_STOP_BITS_2		0x40	/* 1.5 stop bits if FMT_DATA_BITS_5 */
+#define FMT_PARITY_MASK		0x38
+#define FMT_PARITY_NONE		0x00
+#define FMT_PARITY_ODD		0x08
+#define FMT_PARITY_EVEN		0x18
+#define FMT_PARITY_MARK		0x28
+#define FMT_PARITY_SPACE	0x38
+#define FMT_DATA_BITS_MASK	0x03
+#define FMT_DATA_BITS_5		0x00
+#define FMT_DATA_BITS_6		0x01
+#define FMT_DATA_BITS_7		0x02
+#define FMT_DATA_BITS_8		0x03
+	u8	something;	/* always equals 0x43 */
+	u8	control;	/* settings of flow control lines */
+#define CONTROL_MASK		0x0c
+#define CONTROL_DTR_HIGH	0x08
+#define CONTROL_RTS_HIGH	0x04
+	u8	tx_status;
+#define	TX_BUFFER_EMPTIED	0x09
+	u8	pin_state;
+#define PIN_MASK		0x3f
+#define PIN_MSR_MASK		0x1b
+#define PIN_RTS			0x20	/* output pin */
+#define PIN_CTS			0x10	/* input pin, active low */
+#define PIN_DSR			0x08	/* input pin, active low */
+#define PIN_DTR			0x04	/* output pin */
+#define PIN_RI			0x02	/* input pin, active low */
+#define PIN_DCD			0x01	/* input pin, active low */
+	u8	rx_bytes_avail;		/* number of bytes in rx buffer */
+};
+
+#define OTI6858_CTRL_PKT_SIZE	sizeof(struct oti6858_control_pkt)
+#define OTI6858_CTRL_EQUALS_PENDING(a, priv) \
+	(((a)->divisor == (priv)->pending_setup.divisor) \
+	  && ((a)->control == (priv)->pending_setup.control) \
+	  && ((a)->frame_fmt == (priv)->pending_setup.frame_fmt))
+
+/* function prototypes */
+static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port);
+static void oti6858_close(struct usb_serial_port *port);
+static void oti6858_set_termios(struct tty_struct *tty,
+				struct usb_serial_port *port,
+				const struct ktermios *old_termios);
+static void oti6858_init_termios(struct tty_struct *tty);
+static void oti6858_read_int_callback(struct urb *urb);
+static void oti6858_read_bulk_callback(struct urb *urb);
+static void oti6858_write_bulk_callback(struct urb *urb);
+static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
+			const unsigned char *buf, int count);
+static unsigned int oti6858_write_room(struct tty_struct *tty);
+static unsigned int oti6858_chars_in_buffer(struct tty_struct *tty);
+static int oti6858_tiocmget(struct tty_struct *tty);
+static int oti6858_tiocmset(struct tty_struct *tty,
+				unsigned int set, unsigned int clear);
+static int oti6858_port_probe(struct usb_serial_port *port);
+static void oti6858_port_remove(struct usb_serial_port *port);
+
+/* device info */
+static struct usb_serial_driver oti6858_device = {
+	.driver = {
+		.name =		"oti6858",
+	},
+	.id_table =		id_table,
+	.num_ports =		1,
+	.num_bulk_in =		1,
+	.num_bulk_out =		1,
+	.num_interrupt_in =	1,
+	.open =			oti6858_open,
+	.close =		oti6858_close,
+	.write =		oti6858_write,
+	.set_termios =		oti6858_set_termios,
+	.init_termios = 	oti6858_init_termios,
+	.tiocmget =		oti6858_tiocmget,
+	.tiocmset =		oti6858_tiocmset,
+	.tiocmiwait =		usb_serial_generic_tiocmiwait,
+	.read_bulk_callback =	oti6858_read_bulk_callback,
+	.read_int_callback =	oti6858_read_int_callback,
+	.write_bulk_callback =	oti6858_write_bulk_callback,
+	.write_room =		oti6858_write_room,
+	.chars_in_buffer =	oti6858_chars_in_buffer,
+	.port_probe =		oti6858_port_probe,
+	.port_remove =		oti6858_port_remove,
+};
+
+static struct usb_serial_driver * const serial_drivers[] = {
+	&oti6858_device, NULL
+};
+
+struct oti6858_private {
+	spinlock_t lock;
+
+	struct oti6858_control_pkt status;
+
+	struct {
+		u8 read_urb_in_use;
+		u8 write_urb_in_use;
+	} flags;
+	struct delayed_work delayed_write_work;
+
+	struct {
+		__le16 divisor;
+		u8 frame_fmt;
+		u8 control;
+	} pending_setup;
+	u8 transient;
+	u8 setup_done;
+	struct delayed_work delayed_setup_work;
+
+	struct usb_serial_port *port;   /* USB port with which associated */
+};
+
+static void setup_line(struct work_struct *work)
+{
+	struct oti6858_private *priv = container_of(work,
+			struct oti6858_private, delayed_setup_work.work);
+	struct usb_serial_port *port = priv->port;
+	struct oti6858_control_pkt *new_setup;
+	unsigned long flags;
+	int result;
+
+	new_setup = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
+	if (!new_setup) {
+		/* we will try again */
+		schedule_delayed_work(&priv->delayed_setup_work,
+						msecs_to_jiffies(2));
+		return;
+	}
+
+	result = usb_control_msg(port->serial->dev,
+				usb_rcvctrlpipe(port->serial->dev, 0),
+				OTI6858_REQ_T_GET_STATUS,
+				OTI6858_REQ_GET_STATUS,
+				0, 0,
+				new_setup, OTI6858_CTRL_PKT_SIZE,
+				100);
+
+	if (result != OTI6858_CTRL_PKT_SIZE) {
+		dev_err(&port->dev, "%s(): error reading status\n", __func__);
+		kfree(new_setup);
+		/* we will try again */
+		schedule_delayed_work(&priv->delayed_setup_work,
+							msecs_to_jiffies(2));
+		return;
+	}
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (!OTI6858_CTRL_EQUALS_PENDING(new_setup, priv)) {
+		new_setup->divisor = priv->pending_setup.divisor;
+		new_setup->control = priv->pending_setup.control;
+		new_setup->frame_fmt = priv->pending_setup.frame_fmt;
+
+		spin_unlock_irqrestore(&priv->lock, flags);
+		result = usb_control_msg(port->serial->dev,
+					usb_sndctrlpipe(port->serial->dev, 0),
+					OTI6858_REQ_T_SET_LINE,
+					OTI6858_REQ_SET_LINE,
+					0, 0,
+					new_setup, OTI6858_CTRL_PKT_SIZE,
+					100);
+	} else {
+		spin_unlock_irqrestore(&priv->lock, flags);
+		result = 0;
+	}
+	kfree(new_setup);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (result != OTI6858_CTRL_PKT_SIZE)
+		priv->transient = 0;
+	priv->setup_done = 1;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
+	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
+	if (result != 0) {
+		dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
+			__func__, result);
+	}
+}
+
+static void send_data(struct work_struct *work)
+{
+	struct oti6858_private *priv = container_of(work,
+			struct oti6858_private, delayed_write_work.work);
+	struct usb_serial_port *port = priv->port;
+	int count = 0, result;
+	unsigned long flags;
+	u8 *allow;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (priv->flags.write_urb_in_use) {
+		spin_unlock_irqrestore(&priv->lock, flags);
+		schedule_delayed_work(&priv->delayed_write_work,
+						msecs_to_jiffies(2));
+		return;
+	}
+	priv->flags.write_urb_in_use = 1;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	spin_lock_irqsave(&port->lock, flags);
+	count = kfifo_len(&port->write_fifo);
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	if (count > port->bulk_out_size)
+		count = port->bulk_out_size;
+
+	if (count != 0) {
+		allow = kmalloc(1, GFP_KERNEL);
+		if (!allow)
+			return;
+
+		result = usb_control_msg(port->serial->dev,
+				usb_rcvctrlpipe(port->serial->dev, 0),
+				OTI6858_REQ_T_CHECK_TXBUFF,
+				OTI6858_REQ_CHECK_TXBUFF,
+				count, 0, allow, 1, 100);
+		if (result != 1 || *allow != 0)
+			count = 0;
+		kfree(allow);
+	}
+
+	if (count == 0) {
+		priv->flags.write_urb_in_use = 0;
+
+		dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
+		result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
+		if (result != 0) {
+			dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
+				__func__, result);
+		}
+		return;
+	}
+
+	count = kfifo_out_locked(&port->write_fifo,
+					port->write_urb->transfer_buffer,
+					count, &port->lock);
+	port->write_urb->transfer_buffer_length = count;
+	result = usb_submit_urb(port->write_urb, GFP_NOIO);
+	if (result != 0) {
+		dev_err_console(port, "%s(): usb_submit_urb() failed with error %d\n",
+				__func__, result);
+		priv->flags.write_urb_in_use = 0;
+	}
+
+	usb_serial_port_softint(port);
+}
+
+static int oti6858_port_probe(struct usb_serial_port *port)
+{
+	struct oti6858_private *priv;
+
+	priv = kzalloc_obj(*priv);
+	if (!priv)
+		return -ENOMEM;
+
+	spin_lock_init(&priv->lock);
+	priv->port = port;
+	INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
+	INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
+
+	usb_set_serial_port_data(port, priv);
+
+	port->port.drain_delay = 256;	/* FIXME: check the FIFO length */
+
+	return 0;
+}
+
+static void oti6858_port_remove(struct usb_serial_port *port)
+{
+	struct oti6858_private *priv;
+
+	priv = usb_get_serial_port_data(port);
+	kfree(priv);
+}
+
+static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
+			const unsigned char *buf, int count)
+{
+	if (!count)
+		return count;
+
+	count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
+
+	return count;
+}
+
+static unsigned int oti6858_write_room(struct tty_struct *tty)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	unsigned int room;
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->lock, flags);
+	room = kfifo_avail(&port->write_fifo);
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	return room;
+}
+
+static unsigned int oti6858_chars_in_buffer(struct tty_struct *tty)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	unsigned int chars;
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->lock, flags);
+	chars = kfifo_len(&port->write_fifo);
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	return chars;
+}
+
+static void oti6858_init_termios(struct tty_struct *tty)
+{
+	tty_encode_baud_rate(tty, 38400, 38400);
+}
+
+static void oti6858_set_termios(struct tty_struct *tty,
+				struct usb_serial_port *port,
+				const struct ktermios *old_termios)
+{
+	struct oti6858_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+	unsigned int cflag;
+	u8 frame_fmt, control;
+	__le16 divisor;
+	int br;
+
+	cflag = tty->termios.c_cflag;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	frame_fmt = priv->pending_setup.frame_fmt;
+	control = priv->pending_setup.control;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	frame_fmt &= ~FMT_DATA_BITS_MASK;
+	switch (cflag & CSIZE) {
+	case CS5:
+		frame_fmt |= FMT_DATA_BITS_5;
+		break;
+	case CS6:
+		frame_fmt |= FMT_DATA_BITS_6;
+		break;
+	case CS7:
+		frame_fmt |= FMT_DATA_BITS_7;
+		break;
+	default:
+	case CS8:
+		frame_fmt |= FMT_DATA_BITS_8;
+		break;
+	}
+
+	/* manufacturer claims that this device can work with baud rates
+	 * up to 3 Mbps; I've tested it only on 115200 bps, so I can't
+	 * guarantee that any other baud rate will work (especially
+	 * the higher ones)
+	 */
+	br = tty_get_baud_rate(tty);
+	if (br == 0) {
+		divisor = 0;
+	} else {
+		int real_br;
+		int new_divisor;
+		br = min(br, OTI6858_MAX_BAUD_RATE);
+
+		new_divisor = (96000000 + 8 * br) / (16 * br);
+		real_br = 96000000 / (16 * new_divisor);
+		divisor = cpu_to_le16(new_divisor);
+		tty_encode_baud_rate(tty, real_br, real_br);
+	}
+
+	frame_fmt &= ~FMT_STOP_BITS_MASK;
+	if ((cflag & CSTOPB) != 0)
+		frame_fmt |= FMT_STOP_BITS_2;
+	else
+		frame_fmt |= FMT_STOP_BITS_1;
+
+	frame_fmt &= ~FMT_PARITY_MASK;
+	if ((cflag & PARENB) != 0) {
+		if ((cflag & PARODD) != 0)
+			frame_fmt |= FMT_PARITY_ODD;
+		else
+			frame_fmt |= FMT_PARITY_EVEN;
+	} else {
+		frame_fmt |= FMT_PARITY_NONE;
+	}
+
+	control &= ~CONTROL_MASK;
+	if ((cflag & CRTSCTS) != 0)
+		control |= (CONTROL_DTR_HIGH | CONTROL_RTS_HIGH);
+
+	/* change control lines if we are switching to or from B0 */
+	/* FIXME:
+	spin_lock_irqsave(&priv->lock, flags);
+	control = priv->line_control;
+	if ((cflag & CBAUD) == B0)
+		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
+	else
+		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
+	if (control != priv->line_control) {
+		control = priv->line_control;
+		spin_unlock_irqrestore(&priv->lock, flags);
+		set_control_lines(serial->dev, control);
+	} else {
+		spin_unlock_irqrestore(&priv->lock, flags);
+	}
+	*/
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (divisor != priv->pending_setup.divisor
+			|| control != priv->pending_setup.control
+			|| frame_fmt != priv->pending_setup.frame_fmt) {
+		priv->pending_setup.divisor = divisor;
+		priv->pending_setup.control = control;
+		priv->pending_setup.frame_fmt = frame_fmt;
+	}
+	spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port)
+{
+	struct oti6858_private *priv = usb_get_serial_port_data(port);
+	struct usb_serial *serial = port->serial;
+	struct oti6858_control_pkt *buf;
+	unsigned long flags;
+	int result;
+
+	usb_clear_halt(serial->dev, port->write_urb->pipe);
+	usb_clear_halt(serial->dev, port->read_urb->pipe);
+
+	buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
+				OTI6858_REQ_T_GET_STATUS,
+				OTI6858_REQ_GET_STATUS,
+				0, 0,
+				buf, OTI6858_CTRL_PKT_SIZE,
+				100);
+	if (result != OTI6858_CTRL_PKT_SIZE) {
+		/* assume default (after power-on reset) values */
+		buf->divisor = cpu_to_le16(0x009c);	/* 38400 bps */
+		buf->frame_fmt = 0x03;	/* 8N1 */
+		buf->something = 0x43;
+		buf->control = 0x4c;	/* DTR, RTS */
+		buf->tx_status = 0x00;
+		buf->pin_state = 0x5b;	/* RTS, CTS, DSR, DTR, RI, DCD */
+		buf->rx_bytes_avail = 0x00;
+	}
+
+	spin_lock_irqsave(&priv->lock, flags);
+	memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
+	priv->pending_setup.divisor = buf->divisor;
+	priv->pending_setup.frame_fmt = buf->frame_fmt;
+	priv->pending_setup.control = buf->control;
+	spin_unlock_irqrestore(&priv->lock, flags);
+	kfree(buf);
+
+	dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
+	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
+	if (result != 0) {
+		dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
+			__func__, result);
+		oti6858_close(port);
+		return result;
+	}
+
+	/* setup termios */
+	if (tty)
+		oti6858_set_termios(tty, port, NULL);
+
+	return 0;
+}
+
+static void oti6858_close(struct usb_serial_port *port)
+{
+	struct oti6858_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->lock, flags);
+	/* clear out any remaining data in the buffer */
+	kfifo_reset_out(&port->write_fifo);
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	dev_dbg(&port->dev, "%s(): after buf_clear()\n", __func__);
+
+	/* cancel scheduled setup */
+	cancel_delayed_work_sync(&priv->delayed_setup_work);
+	cancel_delayed_work_sync(&priv->delayed_write_work);
+
+	/* shutdown our urbs */
+	dev_dbg(&port->dev, "%s(): shutting down urbs\n", __func__);
+	usb_kill_urb(port->write_urb);
+	usb_kill_urb(port->read_urb);
+	usb_kill_urb(port->interrupt_in_urb);
+}
+
+static int oti6858_tiocmset(struct tty_struct *tty,
+				unsigned int set, unsigned int clear)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	struct oti6858_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+	u8 control;
+
+	dev_dbg(&port->dev, "%s(set = 0x%08x, clear = 0x%08x)\n",
+		__func__, set, clear);
+
+	/* FIXME: check if this is correct (active high/low) */
+	spin_lock_irqsave(&priv->lock, flags);
+	control = priv->pending_setup.control;
+	if ((set & TIOCM_RTS) != 0)
+		control |= CONTROL_RTS_HIGH;
+	if ((set & TIOCM_DTR) != 0)
+		control |= CONTROL_DTR_HIGH;
+	if ((clear & TIOCM_RTS) != 0)
+		control &= ~CONTROL_RTS_HIGH;
+	if ((clear & TIOCM_DTR) != 0)
+		control &= ~CONTROL_DTR_HIGH;
+
+	if (control != priv->pending_setup.control)
+		priv->pending_setup.control = control;
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+	return 0;
+}
+
+static int oti6858_tiocmget(struct tty_struct *tty)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	struct oti6858_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+	unsigned pin_state;
+	unsigned result = 0;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	pin_state = priv->status.pin_state & PIN_MASK;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	/* FIXME: check if this is correct (active high/low) */
+	if ((pin_state & PIN_RTS) != 0)
+		result |= TIOCM_RTS;
+	if ((pin_state & PIN_CTS) != 0)
+		result |= TIOCM_CTS;
+	if ((pin_state & PIN_DSR) != 0)
+		result |= TIOCM_DSR;
+	if ((pin_state & PIN_DTR) != 0)
+		result |= TIOCM_DTR;
+	if ((pin_state & PIN_RI) != 0)
+		result |= TIOCM_RI;
+	if ((pin_state & PIN_DCD) != 0)
+		result |= TIOCM_CD;
+
+	dev_dbg(&port->dev, "%s() = 0x%08x\n", __func__, result);
+
+	return result;
+}
+
+static void oti6858_read_int_callback(struct urb *urb)
+{
+	struct usb_serial_port *port =  urb->context;
+	struct oti6858_private *priv = usb_get_serial_port_data(port);
+	int transient = 0, can_recv = 0, resubmit = 1;
+	int status = urb->status;
+
+	switch (status) {
+	case 0:
+		/* success */
+		break;
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+		/* this urb is terminated, clean up */
+		dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n",
+			__func__, status);
+		return;
+	default:
+		dev_dbg(&urb->dev->dev, "%s(): nonzero urb status received: %d\n",
+			__func__, status);
+		break;
+	}
+
+	if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
+		struct oti6858_control_pkt *xs = urb->transfer_buffer;
+		unsigned long flags;
+
+		spin_lock_irqsave(&priv->lock, flags);
+
+		if (!priv->transient) {
+			if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
+				if (xs->rx_bytes_avail == 0) {
+					priv->transient = 4;
+					priv->setup_done = 0;
+					resubmit = 0;
+					dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
+					schedule_delayed_work(&priv->delayed_setup_work, 0);
+				}
+			}
+		} else {
+			if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
+				priv->transient = 0;
+			} else if (!priv->setup_done) {
+				resubmit = 0;
+			} else if (--priv->transient == 0) {
+				if (xs->rx_bytes_avail == 0) {
+					priv->transient = 4;
+					priv->setup_done = 0;
+					resubmit = 0;
+					dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
+					schedule_delayed_work(&priv->delayed_setup_work, 0);
+				}
+			}
+		}
+
+		if (!priv->transient) {
+			u8 delta = xs->pin_state ^ priv->status.pin_state;
+
+			if (delta & PIN_MSR_MASK) {
+				if (delta & PIN_CTS)
+					port->icount.cts++;
+				if (delta & PIN_DSR)
+					port->icount.dsr++;
+				if (delta & PIN_RI)
+					port->icount.rng++;
+				if (delta & PIN_DCD)
+					port->icount.dcd++;
+
+				wake_up_interruptible(&port->port.delta_msr_wait);
+			}
+
+			memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
+		}
+
+		if (!priv->transient && xs->rx_bytes_avail != 0) {
+			can_recv = xs->rx_bytes_avail;
+			priv->flags.read_urb_in_use = 1;
+		}
+
+		transient = priv->transient;
+		spin_unlock_irqrestore(&priv->lock, flags);
+	}
+
+	if (can_recv) {
+		int result;
+
+		result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
+		if (result != 0) {
+			priv->flags.read_urb_in_use = 0;
+			dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
+					" error %d\n", __func__, result);
+		} else {
+			resubmit = 0;
+		}
+	} else if (!transient) {
+		unsigned long flags;
+		int count;
+
+		spin_lock_irqsave(&port->lock, flags);
+		count = kfifo_len(&port->write_fifo);
+		spin_unlock_irqrestore(&port->lock, flags);
+
+		spin_lock_irqsave(&priv->lock, flags);
+		if (priv->flags.write_urb_in_use == 0 && count != 0) {
+			schedule_delayed_work(&priv->delayed_write_work, 0);
+			resubmit = 0;
+		}
+		spin_unlock_irqrestore(&priv->lock, flags);
+	}
+
+	if (resubmit) {
+		int result;
+
+/*		dev_dbg(&urb->dev->dev, "%s(): submitting interrupt urb\n", __func__); */
+		result = usb_submit_urb(urb, GFP_ATOMIC);
+		if (result != 0) {
+			dev_err(&urb->dev->dev,
+					"%s(): usb_submit_urb() failed with"
+					" error %d\n", __func__, result);
+		}
+	}
+}
+
+static void oti6858_read_bulk_callback(struct urb *urb)
+{
+	struct usb_serial_port *port =  urb->context;
+	struct oti6858_private *priv = usb_get_serial_port_data(port);
+	unsigned char *data = urb->transfer_buffer;
+	unsigned long flags;
+	int status = urb->status;
+	int result;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	priv->flags.read_urb_in_use = 0;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	if (status != 0) {
+		dev_dbg(&urb->dev->dev, "%s(): unable to handle the error, exiting\n", __func__);
+		return;
+	}
+
+	if (urb->actual_length > 0) {
+		tty_insert_flip_string(&port->port, data, urb->actual_length);
+		tty_flip_buffer_push(&port->port);
+	}
+
+	/* schedule the interrupt urb */
+	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
+	if (result != 0 && result != -EPERM) {
+		dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
+				" error %d\n", __func__, result);
+	}
+}
+
+static void oti6858_write_bulk_callback(struct urb *urb)
+{
+	struct usb_serial_port *port =  urb->context;
+	struct oti6858_private *priv = usb_get_serial_port_data(port);
+	int status = urb->status;
+	int result;
+
+	switch (status) {
+	case 0:
+		/* success */
+		break;
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+		/* this urb is terminated, clean up */
+		dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n", __func__, status);
+		priv->flags.write_urb_in_use = 0;
+		return;
+	default:
+		/* error in the urb, so we have to resubmit it */
+		dev_dbg(&urb->dev->dev, "%s(): nonzero write bulk status received: %d\n", __func__, status);
+		dev_dbg(&urb->dev->dev, "%s(): overflow in write\n", __func__);
+
+		port->write_urb->transfer_buffer_length = 1;
+		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
+		if (result) {
+			dev_err_console(port, "%s(): usb_submit_urb() failed,"
+					" error %d\n", __func__, result);
+		} else {
+			return;
+		}
+	}
+
+	priv->flags.write_urb_in_use = 0;
+
+	/* schedule the interrupt urb if we are still open */
+	dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
+	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
+	if (result != 0) {
+		dev_err(&port->dev, "%s(): failed submitting int urb,"
+					" error %d\n", __func__, result);
+	}
+}
+
+module_usb_serial_driver(serial_drivers, id_table);
+
+MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
+MODULE_AUTHOR(OTI6858_AUTHOR);
+MODULE_LICENSE("GPL v2");