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, 1077 insertions, 0 deletions

diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c
new file mode 100644
index 000000000..dcceb95d7
--- /dev/null
+++ b/drivers/usb/serial/f81232.c
@@ -0,0 +1,1077 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Fintek F81232 USB to serial adaptor driver
+ * Fintek F81532A/534A/535/536 USB to 2/4/8/12 serial adaptor driver
+ *
+ * Copyright (C) 2012 Greg Kroah-Hartman (gregkh@linuxfoundation.org)
+ * Copyright (C) 2012 Linux Foundation
+ */
+
+#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/mutex.h>
+#include <linux/usb.h>
+#include <linux/usb/serial.h>
+#include <linux/serial_reg.h>
+
+#define F81232_ID		\
+	{ USB_DEVICE(0x1934, 0x0706) }	/* 1 port UART device */
+
+#define F81534A_SERIES_ID	\
+	{ USB_DEVICE(0x2c42, 0x1602) },	/* In-Box 2 port UART device */	\
+	{ USB_DEVICE(0x2c42, 0x1604) },	/* In-Box 4 port UART device */	\
+	{ USB_DEVICE(0x2c42, 0x1605) },	/* In-Box 8 port UART device */	\
+	{ USB_DEVICE(0x2c42, 0x1606) },	/* In-Box 12 port UART device */ \
+	{ USB_DEVICE(0x2c42, 0x1608) },	/* Non-Flash type */ \
+	{ USB_DEVICE(0x2c42, 0x1632) },	/* 2 port UART device */ \
+	{ USB_DEVICE(0x2c42, 0x1634) },	/* 4 port UART device */ \
+	{ USB_DEVICE(0x2c42, 0x1635) },	/* 8 port UART device */ \
+	{ USB_DEVICE(0x2c42, 0x1636) }	/* 12 port UART device */
+
+#define F81534A_CTRL_ID		\
+	{ USB_DEVICE(0x2c42, 0x16f8) }	/* Global control device */
+
+static const struct usb_device_id f81232_id_table[] = {
+	F81232_ID,
+	{ }					/* Terminating entry */
+};
+
+static const struct usb_device_id f81534a_id_table[] = {
+	F81534A_SERIES_ID,
+	{ }					/* Terminating entry */
+};
+
+static const struct usb_device_id f81534a_ctrl_id_table[] = {
+	F81534A_CTRL_ID,
+	{ }					/* Terminating entry */
+};
+
+static const struct usb_device_id combined_id_table[] = {
+	F81232_ID,
+	F81534A_SERIES_ID,
+	F81534A_CTRL_ID,
+	{ }					/* Terminating entry */
+};
+MODULE_DEVICE_TABLE(usb, combined_id_table);
+
+/* Maximum baudrate for F81232 */
+#define F81232_MAX_BAUDRATE		1500000
+#define F81232_DEF_BAUDRATE		9600
+
+/* USB Control EP parameter */
+#define F81232_REGISTER_REQUEST		0xa0
+#define F81232_GET_REGISTER		0xc0
+#define F81232_SET_REGISTER		0x40
+
+#define SERIAL_BASE_ADDRESS		0x0120
+#define RECEIVE_BUFFER_REGISTER		(0x00 + SERIAL_BASE_ADDRESS)
+#define INTERRUPT_ENABLE_REGISTER	(0x01 + SERIAL_BASE_ADDRESS)
+#define FIFO_CONTROL_REGISTER		(0x02 + SERIAL_BASE_ADDRESS)
+#define LINE_CONTROL_REGISTER		(0x03 + SERIAL_BASE_ADDRESS)
+#define MODEM_CONTROL_REGISTER		(0x04 + SERIAL_BASE_ADDRESS)
+#define LINE_STATUS_REGISTER		(0x05 + SERIAL_BASE_ADDRESS)
+#define MODEM_STATUS_REGISTER		(0x06 + SERIAL_BASE_ADDRESS)
+
+/*
+ * F81232 Clock registers (106h)
+ *
+ * Bit1-0:	Clock source selector
+ *			00: 1.846MHz.
+ *			01: 18.46MHz.
+ *			10: 24MHz.
+ *			11: 14.77MHz.
+ */
+#define F81232_CLK_REGISTER		0x106
+#define F81232_CLK_1_846_MHZ		0
+#define F81232_CLK_18_46_MHZ		BIT(0)
+#define F81232_CLK_24_MHZ		BIT(1)
+#define F81232_CLK_14_77_MHZ		(BIT(1) | BIT(0))
+#define F81232_CLK_MASK			GENMASK(1, 0)
+
+#define F81534A_MODE_REG		0x107
+#define F81534A_TRIGGER_MASK		GENMASK(3, 2)
+#define F81534A_TRIGGER_MULTIPLE_4X	BIT(3)
+#define F81534A_FIFO_128BYTE		(BIT(1) | BIT(0))
+
+/* Serial port self GPIO control, 2bytes [control&output data][input data] */
+#define F81534A_GPIO_REG		0x10e
+#define F81534A_GPIO_MODE2_DIR		BIT(6) /* 1: input, 0: output */
+#define F81534A_GPIO_MODE1_DIR		BIT(5)
+#define F81534A_GPIO_MODE0_DIR		BIT(4)
+#define F81534A_GPIO_MODE2_OUTPUT	BIT(2)
+#define F81534A_GPIO_MODE1_OUTPUT	BIT(1)
+#define F81534A_GPIO_MODE0_OUTPUT	BIT(0)
+
+#define F81534A_CTRL_CMD_ENABLE_PORT	0x116
+
+struct f81232_private {
+	struct mutex lock;
+	u8 modem_control;
+	u8 modem_status;
+	u8 shadow_lcr;
+	speed_t baud_base;
+	struct work_struct lsr_work;
+	struct work_struct interrupt_work;
+	struct usb_serial_port *port;
+};
+
+static u32 const baudrate_table[] = { 115200, 921600, 1152000, 1500000 };
+static u8 const clock_table[] = { F81232_CLK_1_846_MHZ, F81232_CLK_14_77_MHZ,
+				F81232_CLK_18_46_MHZ, F81232_CLK_24_MHZ };
+
+static int calc_baud_divisor(speed_t baudrate, speed_t clockrate)
+{
+	return DIV_ROUND_CLOSEST(clockrate, baudrate);
+}
+
+static int f81232_get_register(struct usb_serial_port *port, u16 reg, u8 *val)
+{
+	int status;
+	struct usb_device *dev = port->serial->dev;
+
+	status = usb_control_msg_recv(dev,
+				      0,
+				      F81232_REGISTER_REQUEST,
+				      F81232_GET_REGISTER,
+				      reg,
+				      0,
+				      val,
+				      sizeof(*val),
+				      USB_CTRL_GET_TIMEOUT,
+				      GFP_KERNEL);
+	if (status) {
+		dev_err(&port->dev, "%s failed status: %d\n", __func__, status);
+		status = usb_translate_errors(status);
+	}
+
+	return status;
+}
+
+static int f81232_set_register(struct usb_serial_port *port, u16 reg, u8 val)
+{
+	int status;
+	struct usb_device *dev = port->serial->dev;
+
+	status = usb_control_msg_send(dev,
+				      0,
+				      F81232_REGISTER_REQUEST,
+				      F81232_SET_REGISTER,
+				      reg,
+				      0,
+				      &val,
+				      sizeof(val),
+				      USB_CTRL_SET_TIMEOUT,
+				      GFP_KERNEL);
+	if (status) {
+		dev_err(&port->dev, "%s failed status: %d\n", __func__, status);
+		status = usb_translate_errors(status);
+	}
+
+	return status;
+}
+
+static int f81232_set_mask_register(struct usb_serial_port *port, u16 reg,
+					u8 mask, u8 val)
+{
+	int status;
+	u8 tmp;
+
+	status = f81232_get_register(port, reg, &tmp);
+	if (status)
+		return status;
+
+	tmp = (tmp & ~mask) | (val & mask);
+
+	return f81232_set_register(port, reg, tmp);
+}
+
+static void f81232_read_msr(struct usb_serial_port *port)
+{
+	int status;
+	u8 current_msr;
+	struct tty_struct *tty;
+	struct f81232_private *priv = usb_get_serial_port_data(port);
+
+	mutex_lock(&priv->lock);
+	status = f81232_get_register(port, MODEM_STATUS_REGISTER,
+			&current_msr);
+	if (status) {
+		dev_err(&port->dev, "%s fail, status: %d\n", __func__, status);
+		mutex_unlock(&priv->lock);
+		return;
+	}
+
+	if (!(current_msr & UART_MSR_ANY_DELTA)) {
+		mutex_unlock(&priv->lock);
+		return;
+	}
+
+	priv->modem_status = current_msr;
+
+	if (current_msr & UART_MSR_DCTS)
+		port->icount.cts++;
+	if (current_msr & UART_MSR_DDSR)
+		port->icount.dsr++;
+	if (current_msr & UART_MSR_TERI)
+		port->icount.rng++;
+	if (current_msr & UART_MSR_DDCD) {
+		port->icount.dcd++;
+		tty = tty_port_tty_get(&port->port);
+		if (tty) {
+			usb_serial_handle_dcd_change(port, tty,
+					current_msr & UART_MSR_DCD);
+
+			tty_kref_put(tty);
+		}
+	}
+
+	wake_up_interruptible(&port->port.delta_msr_wait);
+	mutex_unlock(&priv->lock);
+}
+
+static int f81232_set_mctrl(struct usb_serial_port *port,
+					   unsigned int set, unsigned int clear)
+{
+	u8 val;
+	int status;
+	struct f81232_private *priv = usb_get_serial_port_data(port);
+
+	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0)
+		return 0;	/* no change */
+
+	/* 'set' takes precedence over 'clear' */
+	clear &= ~set;
+
+	/* force enable interrupt with OUT2 */
+	mutex_lock(&priv->lock);
+	val = UART_MCR_OUT2 | priv->modem_control;
+
+	if (clear & TIOCM_DTR)
+		val &= ~UART_MCR_DTR;
+
+	if (clear & TIOCM_RTS)
+		val &= ~UART_MCR_RTS;
+
+	if (set & TIOCM_DTR)
+		val |= UART_MCR_DTR;
+
+	if (set & TIOCM_RTS)
+		val |= UART_MCR_RTS;
+
+	dev_dbg(&port->dev, "%s new:%02x old:%02x\n", __func__,
+			val, priv->modem_control);
+
+	status = f81232_set_register(port, MODEM_CONTROL_REGISTER, val);
+	if (status) {
+		dev_err(&port->dev, "%s set MCR status < 0\n", __func__);
+		mutex_unlock(&priv->lock);
+		return status;
+	}
+
+	priv->modem_control = val;
+	mutex_unlock(&priv->lock);
+
+	return 0;
+}
+
+static void f81232_update_line_status(struct usb_serial_port *port,
+				      unsigned char *data,
+				      size_t actual_length)
+{
+	struct f81232_private *priv = usb_get_serial_port_data(port);
+
+	if (!actual_length)
+		return;
+
+	switch (data[0] & 0x07) {
+	case 0x00: /* msr change */
+		dev_dbg(&port->dev, "IIR: MSR Change: %02x\n", data[0]);
+		schedule_work(&priv->interrupt_work);
+		break;
+	case 0x02: /* tx-empty */
+		break;
+	case 0x04: /* rx data available */
+		break;
+	case 0x06: /* lsr change */
+		/* we can forget it. the LSR will read from bulk-in */
+		dev_dbg(&port->dev, "IIR: LSR Change: %02x\n", data[0]);
+		break;
+	}
+}
+
+static void f81232_read_int_callback(struct urb *urb)
+{
+	struct usb_serial_port *port =  urb->context;
+	unsigned char *data = urb->transfer_buffer;
+	unsigned int actual_length = urb->actual_length;
+	int status = urb->status;
+	int retval;
+
+	switch (status) {
+	case 0:
+		/* success */
+		break;
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+		/* this urb is terminated, clean up */
+		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
+			__func__, status);
+		return;
+	default:
+		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
+			__func__, status);
+		goto exit;
+	}
+
+	usb_serial_debug_data(&port->dev, __func__,
+			      urb->actual_length, urb->transfer_buffer);
+
+	f81232_update_line_status(port, data, actual_length);
+
+exit:
+	retval = usb_submit_urb(urb, GFP_ATOMIC);
+	if (retval)
+		dev_err(&urb->dev->dev,
+			"%s - usb_submit_urb failed with result %d\n",
+			__func__, retval);
+}
+
+static char f81232_handle_lsr(struct usb_serial_port *port, u8 lsr)
+{
+	struct f81232_private *priv = usb_get_serial_port_data(port);
+	char tty_flag = TTY_NORMAL;
+
+	if (!(lsr & UART_LSR_BRK_ERROR_BITS))
+		return tty_flag;
+
+	if (lsr & UART_LSR_BI) {
+		tty_flag = TTY_BREAK;
+		port->icount.brk++;
+		usb_serial_handle_break(port);
+	} else if (lsr & UART_LSR_PE) {
+		tty_flag = TTY_PARITY;
+		port->icount.parity++;
+	} else if (lsr & UART_LSR_FE) {
+		tty_flag = TTY_FRAME;
+		port->icount.frame++;
+	}
+
+	if (lsr & UART_LSR_OE) {
+		port->icount.overrun++;
+		schedule_work(&priv->lsr_work);
+		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
+	}
+
+	return tty_flag;
+}
+
+static void f81232_process_read_urb(struct urb *urb)
+{
+	struct usb_serial_port *port = urb->context;
+	unsigned char *data = urb->transfer_buffer;
+	char tty_flag;
+	unsigned int i;
+	u8 lsr;
+
+	/*
+	 * When opening the port we get a 1-byte packet with the current LSR,
+	 * which we discard.
+	 */
+	if ((urb->actual_length < 2) || (urb->actual_length % 2))
+		return;
+
+	/* bulk-in data: [LSR(1Byte)+DATA(1Byte)][LSR(1Byte)+DATA(1Byte)]... */
+
+	for (i = 0; i < urb->actual_length; i += 2) {
+		lsr = data[i];
+		tty_flag = f81232_handle_lsr(port, lsr);
+
+		if (port->sysrq) {
+			if (usb_serial_handle_sysrq_char(port, data[i + 1]))
+				continue;
+		}
+
+		tty_insert_flip_char(&port->port, data[i + 1], tty_flag);
+	}
+
+	tty_flip_buffer_push(&port->port);
+}
+
+static void f81534a_process_read_urb(struct urb *urb)
+{
+	struct usb_serial_port *port = urb->context;
+	unsigned char *data = urb->transfer_buffer;
+	char tty_flag;
+	unsigned int i;
+	u8 lsr;
+	u8 len;
+
+	if (urb->actual_length < 3) {
+		dev_err(&port->dev, "short message received: %d\n",
+				urb->actual_length);
+		return;
+	}
+
+	len = data[0];
+	if (len != urb->actual_length) {
+		dev_err(&port->dev, "malformed message received: %d (%d)\n",
+				urb->actual_length, len);
+		return;
+	}
+
+	/* bulk-in data: [LEN][Data.....][LSR] */
+	lsr = data[len - 1];
+	tty_flag = f81232_handle_lsr(port, lsr);
+
+	if (port->sysrq) {
+		for (i = 1; i < len - 1; ++i) {
+			if (!usb_serial_handle_sysrq_char(port, data[i])) {
+				tty_insert_flip_char(&port->port, data[i],
+						tty_flag);
+			}
+		}
+	} else {
+		tty_insert_flip_string_fixed_flag(&port->port, &data[1],
+							tty_flag, len - 2);
+	}
+
+	tty_flip_buffer_push(&port->port);
+}
+
+static int f81232_break_ctl(struct tty_struct *tty, int break_state)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	struct f81232_private *priv = usb_get_serial_port_data(port);
+	int status;
+
+	mutex_lock(&priv->lock);
+
+	if (break_state)
+		priv->shadow_lcr |= UART_LCR_SBC;
+	else
+		priv->shadow_lcr &= ~UART_LCR_SBC;
+
+	status = f81232_set_register(port, LINE_CONTROL_REGISTER,
+					priv->shadow_lcr);
+	if (status)
+		dev_err(&port->dev, "set break failed: %d\n", status);
+
+	mutex_unlock(&priv->lock);
+
+	return status;
+}
+
+static int f81232_find_clk(speed_t baudrate)
+{
+	int idx;
+
+	for (idx = 0; idx < ARRAY_SIZE(baudrate_table); ++idx) {
+		if (baudrate <= baudrate_table[idx] &&
+				baudrate_table[idx] % baudrate == 0)
+			return idx;
+	}
+
+	return -EINVAL;
+}
+
+static void f81232_set_baudrate(struct tty_struct *tty,
+				struct usb_serial_port *port, speed_t baudrate,
+				speed_t old_baudrate)
+{
+	struct f81232_private *priv = usb_get_serial_port_data(port);
+	u8 lcr;
+	int divisor;
+	int status = 0;
+	int i;
+	int idx;
+	speed_t baud_list[] = { baudrate, old_baudrate, F81232_DEF_BAUDRATE };
+
+	for (i = 0; i < ARRAY_SIZE(baud_list); ++i) {
+		baudrate = baud_list[i];
+		if (baudrate == 0) {
+			tty_encode_baud_rate(tty, 0, 0);
+			return;
+		}
+
+		idx = f81232_find_clk(baudrate);
+		if (idx >= 0) {
+			tty_encode_baud_rate(tty, baudrate, baudrate);
+			break;
+		}
+	}
+
+	if (idx < 0)
+		return;
+
+	priv->baud_base = baudrate_table[idx];
+	divisor = calc_baud_divisor(baudrate, priv->baud_base);
+
+	status = f81232_set_mask_register(port, F81232_CLK_REGISTER,
+			F81232_CLK_MASK, clock_table[idx]);
+	if (status) {
+		dev_err(&port->dev, "%s failed to set CLK_REG: %d\n",
+			__func__, status);
+		return;
+	}
+
+	status = f81232_get_register(port, LINE_CONTROL_REGISTER,
+			 &lcr); /* get LCR */
+	if (status) {
+		dev_err(&port->dev, "%s failed to get LCR: %d\n",
+			__func__, status);
+		return;
+	}
+
+	status = f81232_set_register(port, LINE_CONTROL_REGISTER,
+			 lcr | UART_LCR_DLAB); /* Enable DLAB */
+	if (status) {
+		dev_err(&port->dev, "%s failed to set DLAB: %d\n",
+			__func__, status);
+		return;
+	}
+
+	status = f81232_set_register(port, RECEIVE_BUFFER_REGISTER,
+			 divisor & 0x00ff); /* low */
+	if (status) {
+		dev_err(&port->dev, "%s failed to set baudrate MSB: %d\n",
+			__func__, status);
+		goto reapply_lcr;
+	}
+
+	status = f81232_set_register(port, INTERRUPT_ENABLE_REGISTER,
+			 (divisor & 0xff00) >> 8); /* high */
+	if (status) {
+		dev_err(&port->dev, "%s failed to set baudrate LSB: %d\n",
+			__func__, status);
+	}
+
+reapply_lcr:
+	status = f81232_set_register(port, LINE_CONTROL_REGISTER,
+			lcr & ~UART_LCR_DLAB);
+	if (status) {
+		dev_err(&port->dev, "%s failed to set DLAB: %d\n",
+			__func__, status);
+	}
+}
+
+static int f81232_port_enable(struct usb_serial_port *port)
+{
+	u8 val;
+	int status;
+
+	/* fifo on, trigger8, clear TX/RX*/
+	val = UART_FCR_TRIGGER_8 | UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR |
+			UART_FCR_CLEAR_XMIT;
+
+	status = f81232_set_register(port, FIFO_CONTROL_REGISTER, val);
+	if (status) {
+		dev_err(&port->dev, "%s failed to set FCR: %d\n",
+			__func__, status);
+		return status;
+	}
+
+	/* MSR Interrupt only, LSR will read from Bulk-in odd byte */
+	status = f81232_set_register(port, INTERRUPT_ENABLE_REGISTER,
+			UART_IER_MSI);
+	if (status) {
+		dev_err(&port->dev, "%s failed to set IER: %d\n",
+			__func__, status);
+		return status;
+	}
+
+	return 0;
+}
+
+static int f81232_port_disable(struct usb_serial_port *port)
+{
+	int status;
+
+	status = f81232_set_register(port, INTERRUPT_ENABLE_REGISTER, 0);
+	if (status) {
+		dev_err(&port->dev, "%s failed to set IER: %d\n",
+			__func__, status);
+		return status;
+	}
+
+	return 0;
+}
+
+static void f81232_set_termios(struct tty_struct *tty,
+			       struct usb_serial_port *port,
+			       const struct ktermios *old_termios)
+{
+	struct f81232_private *priv = usb_get_serial_port_data(port);
+	u8 new_lcr = 0;
+	int status = 0;
+	speed_t baudrate;
+	speed_t old_baud;
+
+	/* Don't change anything if nothing has changed */
+	if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
+		return;
+
+	if (C_BAUD(tty) == B0)
+		f81232_set_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
+	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
+		f81232_set_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
+
+	baudrate = tty_get_baud_rate(tty);
+	if (baudrate > 0) {
+		if (old_termios)
+			old_baud = tty_termios_baud_rate(old_termios);
+		else
+			old_baud = F81232_DEF_BAUDRATE;
+
+		f81232_set_baudrate(tty, port, baudrate, old_baud);
+	}
+
+	if (C_PARENB(tty)) {
+		new_lcr |= UART_LCR_PARITY;
+
+		if (!C_PARODD(tty))
+			new_lcr |= UART_LCR_EPAR;
+
+		if (C_CMSPAR(tty))
+			new_lcr |= UART_LCR_SPAR;
+	}
+
+	if (C_CSTOPB(tty))
+		new_lcr |= UART_LCR_STOP;
+
+	new_lcr |= UART_LCR_WLEN(tty_get_char_size(tty->termios.c_cflag));
+
+	mutex_lock(&priv->lock);
+
+	new_lcr |= (priv->shadow_lcr & UART_LCR_SBC);
+	status = f81232_set_register(port, LINE_CONTROL_REGISTER, new_lcr);
+	if (status) {
+		dev_err(&port->dev, "%s failed to set LCR: %d\n",
+			__func__, status);
+	}
+
+	priv->shadow_lcr = new_lcr;
+
+	mutex_unlock(&priv->lock);
+}
+
+static int f81232_tiocmget(struct tty_struct *tty)
+{
+	int r;
+	struct usb_serial_port *port = tty->driver_data;
+	struct f81232_private *port_priv = usb_get_serial_port_data(port);
+	u8 mcr, msr;
+
+	/* force get current MSR changed state */
+	f81232_read_msr(port);
+
+	mutex_lock(&port_priv->lock);
+	mcr = port_priv->modem_control;
+	msr = port_priv->modem_status;
+	mutex_unlock(&port_priv->lock);
+
+	r = (mcr & UART_MCR_DTR ? TIOCM_DTR : 0) |
+		(mcr & UART_MCR_RTS ? TIOCM_RTS : 0) |
+		(msr & UART_MSR_CTS ? TIOCM_CTS : 0) |
+		(msr & UART_MSR_DCD ? TIOCM_CAR : 0) |
+		(msr & UART_MSR_RI ? TIOCM_RI : 0) |
+		(msr & UART_MSR_DSR ? TIOCM_DSR : 0);
+
+	return r;
+}
+
+static int f81232_tiocmset(struct tty_struct *tty,
+			unsigned int set, unsigned int clear)
+{
+	struct usb_serial_port *port = tty->driver_data;
+
+	return f81232_set_mctrl(port, set, clear);
+}
+
+static int f81232_open(struct tty_struct *tty, struct usb_serial_port *port)
+{
+	int result;
+
+	result = f81232_port_enable(port);
+	if (result)
+		return result;
+
+	/* Setup termios */
+	if (tty)
+		f81232_set_termios(tty, port, NULL);
+
+	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
+	if (result) {
+		dev_err(&port->dev, "%s - failed submitting interrupt urb,"
+			" error %d\n", __func__, result);
+		return result;
+	}
+
+	result = usb_serial_generic_open(tty, port);
+	if (result) {
+		usb_kill_urb(port->interrupt_in_urb);
+		return result;
+	}
+
+	return 0;
+}
+
+static int f81534a_open(struct tty_struct *tty, struct usb_serial_port *port)
+{
+	int status;
+	u8 mask;
+	u8 val;
+
+	val = F81534A_TRIGGER_MULTIPLE_4X | F81534A_FIFO_128BYTE;
+	mask = F81534A_TRIGGER_MASK | F81534A_FIFO_128BYTE;
+
+	status = f81232_set_mask_register(port, F81534A_MODE_REG, mask, val);
+	if (status) {
+		dev_err(&port->dev, "failed to set MODE_REG: %d\n", status);
+		return status;
+	}
+
+	return f81232_open(tty, port);
+}
+
+static void f81232_close(struct usb_serial_port *port)
+{
+	struct f81232_private *port_priv = usb_get_serial_port_data(port);
+
+	f81232_port_disable(port);
+	usb_serial_generic_close(port);
+	usb_kill_urb(port->interrupt_in_urb);
+	flush_work(&port_priv->interrupt_work);
+	flush_work(&port_priv->lsr_work);
+}
+
+static void f81232_dtr_rts(struct usb_serial_port *port, int on)
+{
+	if (on)
+		f81232_set_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
+	else
+		f81232_set_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
+}
+
+static bool f81232_tx_empty(struct usb_serial_port *port)
+{
+	int status;
+	u8 tmp;
+
+	status = f81232_get_register(port, LINE_STATUS_REGISTER, &tmp);
+	if (!status) {
+		if ((tmp & UART_LSR_TEMT) != UART_LSR_TEMT)
+			return false;
+	}
+
+	return true;
+}
+
+static int f81232_carrier_raised(struct usb_serial_port *port)
+{
+	u8 msr;
+	struct f81232_private *priv = usb_get_serial_port_data(port);
+
+	mutex_lock(&priv->lock);
+	msr = priv->modem_status;
+	mutex_unlock(&priv->lock);
+
+	if (msr & UART_MSR_DCD)
+		return 1;
+	return 0;
+}
+
+static void f81232_get_serial(struct tty_struct *tty, struct serial_struct *ss)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	struct f81232_private *priv = usb_get_serial_port_data(port);
+
+	ss->baud_base = priv->baud_base;
+}
+
+static void  f81232_interrupt_work(struct work_struct *work)
+{
+	struct f81232_private *priv =
+		container_of(work, struct f81232_private, interrupt_work);
+
+	f81232_read_msr(priv->port);
+}
+
+static void f81232_lsr_worker(struct work_struct *work)
+{
+	struct f81232_private *priv;
+	struct usb_serial_port *port;
+	int status;
+	u8 tmp;
+
+	priv = container_of(work, struct f81232_private, lsr_work);
+	port = priv->port;
+
+	status = f81232_get_register(port, LINE_STATUS_REGISTER, &tmp);
+	if (status)
+		dev_warn(&port->dev, "read LSR failed: %d\n", status);
+}
+
+static int f81534a_ctrl_set_register(struct usb_interface *intf, u16 reg,
+					u16 size, void *val)
+{
+	return usb_control_msg_send(interface_to_usbdev(intf),
+						0,
+						F81232_REGISTER_REQUEST,
+						F81232_SET_REGISTER,
+						reg,
+						0,
+						val,
+						size,
+						USB_CTRL_SET_TIMEOUT,
+						GFP_KERNEL);
+}
+
+static int f81534a_ctrl_get_register(struct usb_interface *intf, u16 reg,
+					u16 size, void *val)
+{
+	return usb_control_msg_recv(interface_to_usbdev(intf),
+						0,
+						F81232_REGISTER_REQUEST,
+						F81232_GET_REGISTER,
+						reg,
+						0,
+						val,
+						size,
+						USB_CTRL_GET_TIMEOUT,
+						GFP_KERNEL);
+}
+
+static int f81534a_ctrl_enable_all_ports(struct usb_interface *intf, bool en)
+{
+	unsigned char enable[2] = {0};
+	int status;
+
+	/*
+	 * Enable all available serial ports, define as following:
+	 * bit 15	: Reset behavior (when HUB got soft reset)
+	 *			0: maintain all serial port enabled state.
+	 *			1: disable all serial port.
+	 * bit 0~11	: Serial port enable bit.
+	 */
+	if (en) {
+		/*
+		 * The Fintek F81532A/534A/535/536 family relies on the
+		 * F81534A_CTRL_CMD_ENABLE_PORT (116h) register during
+		 * initialization to both determine serial port status and
+		 * control port creation.
+		 *
+		 * If the driver experiences fast load/unload cycles, the
+		 * device state may becomes unstable, resulting in the
+		 * incomplete generation of serial ports.
+		 *
+		 * Performing a dummy read operation on the register prior
+		 * to the initial write command resolves the issue.
+		 *
+		 * This clears the device's stale internal state. Subsequent
+		 * write operations will correctly generate all serial ports.
+		 */
+		status = f81534a_ctrl_get_register(intf,
+						F81534A_CTRL_CMD_ENABLE_PORT,
+						sizeof(enable),
+						enable);
+		if (status)
+			return status;
+
+		enable[0] = 0xff;
+		enable[1] = 0x8f;
+	}
+
+	status = f81534a_ctrl_set_register(intf, F81534A_CTRL_CMD_ENABLE_PORT,
+			sizeof(enable), enable);
+	if (status)
+		dev_err(&intf->dev, "failed to enable ports: %d\n", status);
+
+	return status;
+}
+
+static int f81534a_ctrl_probe(struct usb_interface *intf,
+				const struct usb_device_id *id)
+{
+	return f81534a_ctrl_enable_all_ports(intf, true);
+}
+
+static void f81534a_ctrl_disconnect(struct usb_interface *intf)
+{
+	f81534a_ctrl_enable_all_ports(intf, false);
+}
+
+static int f81534a_ctrl_resume(struct usb_interface *intf)
+{
+	return f81534a_ctrl_enable_all_ports(intf, true);
+}
+
+static int f81232_port_probe(struct usb_serial_port *port)
+{
+	struct f81232_private *priv;
+
+	priv = devm_kzalloc(&port->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	mutex_init(&priv->lock);
+	INIT_WORK(&priv->interrupt_work,  f81232_interrupt_work);
+	INIT_WORK(&priv->lsr_work, f81232_lsr_worker);
+
+	usb_set_serial_port_data(port, priv);
+
+	priv->port = port;
+
+	return 0;
+}
+
+static int f81534a_port_probe(struct usb_serial_port *port)
+{
+	int status;
+
+	/* tri-state with pull-high, default RS232 Mode */
+	status = f81232_set_register(port, F81534A_GPIO_REG,
+					F81534A_GPIO_MODE2_DIR);
+	if (status)
+		return status;
+
+	return f81232_port_probe(port);
+}
+
+static int f81232_suspend(struct usb_serial *serial, pm_message_t message)
+{
+	struct usb_serial_port *port = serial->port[0];
+	struct f81232_private *port_priv = usb_get_serial_port_data(port);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
+		usb_kill_urb(port->read_urbs[i]);
+
+	usb_kill_urb(port->interrupt_in_urb);
+
+	if (port_priv) {
+		flush_work(&port_priv->interrupt_work);
+		flush_work(&port_priv->lsr_work);
+	}
+
+	return 0;
+}
+
+static int f81232_resume(struct usb_serial *serial)
+{
+	struct usb_serial_port *port = serial->port[0];
+	int result;
+
+	if (tty_port_initialized(&port->port)) {
+		result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
+		if (result) {
+			dev_err(&port->dev, "submit interrupt urb failed: %d\n",
+					result);
+			return result;
+		}
+	}
+
+	return usb_serial_generic_resume(serial);
+}
+
+static struct usb_serial_driver f81232_device = {
+	.driver = {
+		.name =		"f81232",
+	},
+	.id_table =		f81232_id_table,
+	.num_ports =		1,
+	.bulk_in_size =		256,
+	.bulk_out_size =	256,
+	.open =			f81232_open,
+	.close =		f81232_close,
+	.dtr_rts =		f81232_dtr_rts,
+	.carrier_raised =	f81232_carrier_raised,
+	.get_serial =		f81232_get_serial,
+	.break_ctl =		f81232_break_ctl,
+	.set_termios =		f81232_set_termios,
+	.tiocmget =		f81232_tiocmget,
+	.tiocmset =		f81232_tiocmset,
+	.tiocmiwait =		usb_serial_generic_tiocmiwait,
+	.tx_empty =		f81232_tx_empty,
+	.process_read_urb =	f81232_process_read_urb,
+	.read_int_callback =	f81232_read_int_callback,
+	.port_probe =		f81232_port_probe,
+	.suspend =		f81232_suspend,
+	.resume =		f81232_resume,
+};
+
+static struct usb_serial_driver f81534a_device = {
+	.driver = {
+		.name =		"f81534a",
+	},
+	.id_table =		f81534a_id_table,
+	.num_ports =		1,
+	.open =			f81534a_open,
+	.close =		f81232_close,
+	.dtr_rts =		f81232_dtr_rts,
+	.carrier_raised =	f81232_carrier_raised,
+	.get_serial =		f81232_get_serial,
+	.break_ctl =		f81232_break_ctl,
+	.set_termios =		f81232_set_termios,
+	.tiocmget =		f81232_tiocmget,
+	.tiocmset =		f81232_tiocmset,
+	.tiocmiwait =		usb_serial_generic_tiocmiwait,
+	.tx_empty =		f81232_tx_empty,
+	.process_read_urb =	f81534a_process_read_urb,
+	.read_int_callback =	f81232_read_int_callback,
+	.port_probe =		f81534a_port_probe,
+	.suspend =		f81232_suspend,
+	.resume =		f81232_resume,
+};
+
+static struct usb_serial_driver * const serial_drivers[] = {
+	&f81232_device,
+	&f81534a_device,
+	NULL,
+};
+
+static struct usb_driver f81534a_ctrl_driver = {
+	.name =		"f81534a_ctrl",
+	.id_table =	f81534a_ctrl_id_table,
+	.probe =	f81534a_ctrl_probe,
+	.disconnect =	f81534a_ctrl_disconnect,
+	.resume =	f81534a_ctrl_resume,
+};
+
+static int __init f81232_init(void)
+{
+	int status;
+
+	status = usb_register_driver(&f81534a_ctrl_driver, THIS_MODULE,
+			KBUILD_MODNAME);
+	if (status)
+		return status;
+
+	status = usb_serial_register_drivers(serial_drivers, KBUILD_MODNAME,
+			combined_id_table);
+	if (status) {
+		usb_deregister(&f81534a_ctrl_driver);
+		return status;
+	}
+
+	return 0;
+}
+
+static void __exit f81232_exit(void)
+{
+	usb_serial_deregister_drivers(serial_drivers);
+	usb_deregister(&f81534a_ctrl_driver);
+}
+
+module_init(f81232_init);
+module_exit(f81232_exit);
+
+MODULE_DESCRIPTION("Fintek F81232/532A/534A/535/536 USB to serial driver");
+MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");
+MODULE_AUTHOR("Peter Hong <peter_hong@fintek.com.tw>");
+MODULE_LICENSE("GPL v2");