cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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quatech2.c (24288B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * usb-serial driver for Quatech USB 2 devices
      4 *
      5 * Copyright (C) 2012 Bill Pemberton (wfp5p@virginia.edu)
      6 *
      7 *  These devices all have only 1 bulk in and 1 bulk out that is shared
      8 *  for all serial ports.
      9 *
     10 */
     11
     12#include <asm/unaligned.h>
     13#include <linux/errno.h>
     14#include <linux/slab.h>
     15#include <linux/tty.h>
     16#include <linux/tty_driver.h>
     17#include <linux/tty_flip.h>
     18#include <linux/module.h>
     19#include <linux/serial.h>
     20#include <linux/usb.h>
     21#include <linux/usb/serial.h>
     22#include <linux/serial_reg.h>
     23#include <linux/uaccess.h>
     24
     25/* default urb timeout for usb operations */
     26#define QT2_USB_TIMEOUT USB_CTRL_SET_TIMEOUT
     27
     28#define QT_OPEN_CLOSE_CHANNEL       0xca
     29#define QT_SET_GET_DEVICE           0xc2
     30#define QT_SET_GET_REGISTER         0xc0
     31#define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
     32#define QT_SET_ATF                  0xcd
     33#define QT_TRANSFER_IN              0xc0
     34#define QT_HW_FLOW_CONTROL_MASK     0xc5
     35#define QT_SW_FLOW_CONTROL_MASK     0xc6
     36#define QT2_BREAK_CONTROL	    0xc8
     37#define QT2_GET_SET_UART            0xc1
     38#define QT2_FLUSH_DEVICE	    0xc4
     39#define QT2_GET_SET_QMCR            0xe1
     40#define QT2_QMCR_RS232              0x40
     41#define QT2_QMCR_RS422              0x10
     42
     43#define  SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS)
     44
     45#define  SERIAL_EVEN_PARITY         (UART_LCR_PARITY | UART_LCR_EPAR)
     46
     47/* status bytes for the device */
     48#define QT2_CONTROL_BYTE    0x1b
     49#define QT2_LINE_STATUS     0x00  /* following 1 byte is line status */
     50#define QT2_MODEM_STATUS    0x01  /* following 1 byte is modem status */
     51#define QT2_XMIT_HOLD       0x02  /* following 2 bytes are ?? */
     52#define QT2_CHANGE_PORT     0x03  /* following 1 byte is port to change to */
     53#define QT2_REC_FLUSH       0x04  /* no following info */
     54#define QT2_XMIT_FLUSH      0x05  /* no following info */
     55#define QT2_CONTROL_ESCAPE  0xff  /* pass through previous 2 control bytes */
     56
     57#define  MAX_BAUD_RATE              921600
     58#define  DEFAULT_BAUD_RATE          9600
     59
     60#define QT2_READ_BUFFER_SIZE    512  /* size of read buffer */
     61#define QT2_WRITE_BUFFER_SIZE   512  /* size of write buffer */
     62#define QT2_WRITE_CONTROL_SIZE  5    /* control bytes used for a write */
     63
     64#define DRIVER_DESC "Quatech 2nd gen USB to Serial Driver"
     65
     66#define	USB_VENDOR_ID_QUATECH	0x061d
     67#define QUATECH_SSU2_100	0xC120	/* RS232 single port */
     68#define QUATECH_DSU2_100	0xC140	/* RS232 dual port */
     69#define QUATECH_DSU2_400	0xC150	/* RS232/422/485 dual port */
     70#define QUATECH_QSU2_100	0xC160	/* RS232 four port */
     71#define QUATECH_QSU2_400	0xC170	/* RS232/422/485 four port */
     72#define QUATECH_ESU2_100	0xC1A0	/* RS232 eight port */
     73#define QUATECH_ESU2_400	0xC180	/* RS232/422/485 eight port */
     74
     75struct qt2_device_detail {
     76	int product_id;
     77	int num_ports;
     78};
     79
     80#define QT_DETAILS(prod, ports)	\
     81	.product_id = (prod),   \
     82	.num_ports = (ports)
     83
     84static const struct qt2_device_detail qt2_device_details[] = {
     85	{QT_DETAILS(QUATECH_SSU2_100, 1)},
     86	{QT_DETAILS(QUATECH_DSU2_400, 2)},
     87	{QT_DETAILS(QUATECH_DSU2_100, 2)},
     88	{QT_DETAILS(QUATECH_QSU2_400, 4)},
     89	{QT_DETAILS(QUATECH_QSU2_100, 4)},
     90	{QT_DETAILS(QUATECH_ESU2_400, 8)},
     91	{QT_DETAILS(QUATECH_ESU2_100, 8)},
     92	{QT_DETAILS(0, 0)}	/* Terminating entry */
     93};
     94
     95static const struct usb_device_id id_table[] = {
     96	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU2_100)},
     97	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_DSU2_100)},
     98	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_DSU2_400)},
     99	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_QSU2_100)},
    100	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_QSU2_400)},
    101	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_ESU2_100)},
    102	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_ESU2_400)},
    103	{}			/* Terminating entry */
    104};
    105MODULE_DEVICE_TABLE(usb, id_table);
    106
    107struct qt2_serial_private {
    108	unsigned char current_port;  /* current port for incoming data */
    109
    110	struct urb	*read_urb;   /* shared among all ports */
    111	char		*read_buffer;
    112};
    113
    114struct qt2_port_private {
    115	u8   device_port;
    116
    117	spinlock_t urb_lock;
    118	bool       urb_in_use;
    119	struct urb *write_urb;
    120	char       *write_buffer;
    121
    122	spinlock_t  lock;
    123	u8          shadowLSR;
    124	u8          shadowMSR;
    125
    126	struct usb_serial_port *port;
    127};
    128
    129static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch);
    130static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch);
    131static void qt2_write_bulk_callback(struct urb *urb);
    132static void qt2_read_bulk_callback(struct urb *urb);
    133
    134static void qt2_release(struct usb_serial *serial)
    135{
    136	struct qt2_serial_private *serial_priv;
    137
    138	serial_priv = usb_get_serial_data(serial);
    139
    140	usb_kill_urb(serial_priv->read_urb);
    141	usb_free_urb(serial_priv->read_urb);
    142	kfree(serial_priv->read_buffer);
    143	kfree(serial_priv);
    144}
    145
    146static inline int calc_baud_divisor(int baudrate)
    147{
    148	int divisor, rem;
    149
    150	divisor = MAX_BAUD_RATE / baudrate;
    151	rem = MAX_BAUD_RATE % baudrate;
    152	/* Round to nearest divisor */
    153	if (((rem * 2) >= baudrate) && (baudrate != 110))
    154		divisor++;
    155
    156	return divisor;
    157}
    158
    159static inline int qt2_set_port_config(struct usb_device *dev,
    160				      unsigned char port_number,
    161				      u16 baudrate, u16 lcr)
    162{
    163	int divisor = calc_baud_divisor(baudrate);
    164	u16 index = ((u16) (lcr << 8) | (u16) (port_number));
    165
    166	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
    167			       QT2_GET_SET_UART, 0x40,
    168			       divisor, index, NULL, 0, QT2_USB_TIMEOUT);
    169}
    170
    171static inline int qt2_control_msg(struct usb_device *dev,
    172				  u8 request, u16 data, u16 index)
    173{
    174	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
    175			       request, 0x40, data, index,
    176			       NULL, 0, QT2_USB_TIMEOUT);
    177}
    178
    179static inline int qt2_setdevice(struct usb_device *dev, u8 *data)
    180{
    181	u16 x = ((u16) (data[1] << 8) | (u16) (data[0]));
    182
    183	return qt2_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
    184}
    185
    186
    187static inline int qt2_getregister(struct usb_device *dev,
    188				  u8 uart,
    189				  u8 reg,
    190				  u8 *data)
    191{
    192	int ret;
    193
    194	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
    195			      QT_SET_GET_REGISTER, 0xc0, reg,
    196			      uart, data, sizeof(*data), QT2_USB_TIMEOUT);
    197	if (ret < (int)sizeof(*data)) {
    198		if (ret >= 0)
    199			ret = -EIO;
    200	}
    201
    202	return ret;
    203}
    204
    205static inline int qt2_setregister(struct usb_device *dev,
    206				  u8 uart, u8 reg, u16 data)
    207{
    208	u16 value = (data << 8) | reg;
    209
    210	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
    211			       QT_SET_GET_REGISTER, 0x40, value, uart,
    212			       NULL, 0, QT2_USB_TIMEOUT);
    213}
    214
    215static inline int update_mctrl(struct qt2_port_private *port_priv,
    216			       unsigned int set, unsigned int clear)
    217{
    218	struct usb_serial_port *port = port_priv->port;
    219	struct usb_device *dev = port->serial->dev;
    220	unsigned urb_value;
    221	int status;
    222
    223	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
    224		dev_dbg(&port->dev,
    225			"update_mctrl - DTR|RTS not being set|cleared\n");
    226		return 0;	/* no change */
    227	}
    228
    229	clear &= ~set;	/* 'set' takes precedence over 'clear' */
    230	urb_value = 0;
    231	if (set & TIOCM_DTR)
    232		urb_value |= UART_MCR_DTR;
    233	if (set & TIOCM_RTS)
    234		urb_value |= UART_MCR_RTS;
    235
    236	status = qt2_setregister(dev, port_priv->device_port, UART_MCR,
    237				 urb_value);
    238	if (status < 0)
    239		dev_err(&port->dev,
    240			"update_mctrl - Error from MODEM_CTRL urb: %i\n",
    241			status);
    242	return status;
    243}
    244
    245static int qt2_calc_num_ports(struct usb_serial *serial,
    246					struct usb_serial_endpoints *epds)
    247{
    248	struct qt2_device_detail d;
    249	int i;
    250
    251	for (i = 0; d = qt2_device_details[i], d.product_id != 0; i++) {
    252		if (d.product_id == le16_to_cpu(serial->dev->descriptor.idProduct))
    253			return d.num_ports;
    254	}
    255
    256	/* we didn't recognize the device */
    257	dev_err(&serial->dev->dev,
    258		 "don't know the number of ports, assuming 1\n");
    259
    260	return 1;
    261}
    262
    263static void qt2_set_termios(struct tty_struct *tty,
    264			    struct usb_serial_port *port,
    265			    struct ktermios *old_termios)
    266{
    267	struct usb_device *dev = port->serial->dev;
    268	struct qt2_port_private *port_priv;
    269	struct ktermios *termios = &tty->termios;
    270	u16 baud;
    271	unsigned int cflag = termios->c_cflag;
    272	u16 new_lcr = 0;
    273	int status;
    274
    275	port_priv = usb_get_serial_port_data(port);
    276
    277	if (cflag & PARENB) {
    278		if (cflag & PARODD)
    279			new_lcr |= UART_LCR_PARITY;
    280		else
    281			new_lcr |= SERIAL_EVEN_PARITY;
    282	}
    283
    284	new_lcr |= UART_LCR_WLEN(tty_get_char_size(cflag));
    285
    286	baud = tty_get_baud_rate(tty);
    287	if (!baud)
    288		baud = 9600;
    289
    290	status = qt2_set_port_config(dev, port_priv->device_port, baud,
    291				     new_lcr);
    292	if (status < 0)
    293		dev_err(&port->dev, "%s - qt2_set_port_config failed: %i\n",
    294			__func__, status);
    295
    296	if (cflag & CRTSCTS)
    297		status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
    298					 SERIAL_CRTSCTS,
    299					 port_priv->device_port);
    300	else
    301		status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
    302					 0, port_priv->device_port);
    303	if (status < 0)
    304		dev_err(&port->dev, "%s - set HW flow control failed: %i\n",
    305			__func__, status);
    306
    307	if (I_IXOFF(tty) || I_IXON(tty)) {
    308		u16 x = ((u16) (START_CHAR(tty) << 8) | (u16) (STOP_CHAR(tty)));
    309
    310		status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
    311					 x, port_priv->device_port);
    312	} else
    313		status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
    314					 0, port_priv->device_port);
    315
    316	if (status < 0)
    317		dev_err(&port->dev, "%s - set SW flow control failed: %i\n",
    318			__func__, status);
    319
    320}
    321
    322static int qt2_open(struct tty_struct *tty, struct usb_serial_port *port)
    323{
    324	struct usb_serial *serial;
    325	struct qt2_port_private *port_priv;
    326	u8 *data;
    327	u16 device_port;
    328	int status;
    329	unsigned long flags;
    330
    331	device_port = port->port_number;
    332
    333	serial = port->serial;
    334
    335	port_priv = usb_get_serial_port_data(port);
    336
    337	/* set the port to RS232 mode */
    338	status = qt2_control_msg(serial->dev, QT2_GET_SET_QMCR,
    339				 QT2_QMCR_RS232, device_port);
    340	if (status < 0) {
    341		dev_err(&port->dev,
    342			"%s failed to set RS232 mode for port %i error %i\n",
    343			__func__, device_port, status);
    344		return status;
    345	}
    346
    347	data = kzalloc(2, GFP_KERNEL);
    348	if (!data)
    349		return -ENOMEM;
    350
    351	/* open the port */
    352	status = usb_control_msg(serial->dev,
    353				 usb_rcvctrlpipe(serial->dev, 0),
    354				 QT_OPEN_CLOSE_CHANNEL,
    355				 0xc0, 0,
    356				 device_port, data, 2, QT2_USB_TIMEOUT);
    357
    358	if (status < 2) {
    359		dev_err(&port->dev, "%s - open port failed %i\n", __func__,
    360			status);
    361		if (status >= 0)
    362			status = -EIO;
    363		kfree(data);
    364		return status;
    365	}
    366
    367	spin_lock_irqsave(&port_priv->lock, flags);
    368	port_priv->shadowLSR = data[0];
    369	port_priv->shadowMSR = data[1];
    370	spin_unlock_irqrestore(&port_priv->lock, flags);
    371
    372	kfree(data);
    373
    374	/* set to default speed and 8bit word size */
    375	status = qt2_set_port_config(serial->dev, device_port,
    376				     DEFAULT_BAUD_RATE, UART_LCR_WLEN8);
    377	if (status < 0) {
    378		dev_err(&port->dev, "%s - initial setup failed (%i)\n",
    379			__func__, device_port);
    380		return status;
    381	}
    382
    383	port_priv->device_port = (u8) device_port;
    384
    385	if (tty)
    386		qt2_set_termios(tty, port, &tty->termios);
    387
    388	return 0;
    389
    390}
    391
    392static void qt2_close(struct usb_serial_port *port)
    393{
    394	struct usb_serial *serial;
    395	struct qt2_port_private *port_priv;
    396	int i;
    397
    398	serial = port->serial;
    399	port_priv = usb_get_serial_port_data(port);
    400
    401	usb_kill_urb(port_priv->write_urb);
    402
    403	/* flush the port transmit buffer */
    404	i = usb_control_msg(serial->dev,
    405			    usb_sndctrlpipe(serial->dev, 0),
    406			    QT2_FLUSH_DEVICE, 0x40, 1,
    407			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
    408
    409	if (i < 0)
    410		dev_err(&port->dev, "%s - transmit buffer flush failed: %i\n",
    411			__func__, i);
    412
    413	/* flush the port receive buffer */
    414	i = usb_control_msg(serial->dev,
    415			    usb_sndctrlpipe(serial->dev, 0),
    416			    QT2_FLUSH_DEVICE, 0x40, 0,
    417			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
    418
    419	if (i < 0)
    420		dev_err(&port->dev, "%s - receive buffer flush failed: %i\n",
    421			__func__, i);
    422
    423	/* close the port */
    424	i = usb_control_msg(serial->dev,
    425			    usb_sndctrlpipe(serial->dev, 0),
    426			    QT_OPEN_CLOSE_CHANNEL,
    427			    0x40, 0,
    428			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
    429
    430	if (i < 0)
    431		dev_err(&port->dev, "%s - close port failed %i\n",
    432			__func__, i);
    433}
    434
    435static void qt2_disconnect(struct usb_serial *serial)
    436{
    437	struct qt2_serial_private *serial_priv = usb_get_serial_data(serial);
    438
    439	usb_kill_urb(serial_priv->read_urb);
    440}
    441
    442static void qt2_process_status(struct usb_serial_port *port, unsigned char *ch)
    443{
    444	switch (*ch) {
    445	case QT2_LINE_STATUS:
    446		qt2_update_lsr(port, ch + 1);
    447		break;
    448	case QT2_MODEM_STATUS:
    449		qt2_update_msr(port, ch + 1);
    450		break;
    451	}
    452}
    453
    454static void qt2_process_read_urb(struct urb *urb)
    455{
    456	struct usb_serial *serial;
    457	struct qt2_serial_private *serial_priv;
    458	struct usb_serial_port *port;
    459	bool escapeflag;
    460	unsigned char *ch;
    461	int i;
    462	unsigned char newport;
    463	int len = urb->actual_length;
    464
    465	if (!len)
    466		return;
    467
    468	ch = urb->transfer_buffer;
    469	serial = urb->context;
    470	serial_priv = usb_get_serial_data(serial);
    471	port = serial->port[serial_priv->current_port];
    472
    473	for (i = 0; i < urb->actual_length; i++) {
    474		ch = (unsigned char *)urb->transfer_buffer + i;
    475		if ((i <= (len - 3)) &&
    476		    (*ch == QT2_CONTROL_BYTE) &&
    477		    (*(ch + 1) == QT2_CONTROL_BYTE)) {
    478			escapeflag = false;
    479			switch (*(ch + 2)) {
    480			case QT2_LINE_STATUS:
    481			case QT2_MODEM_STATUS:
    482				if (i > (len - 4)) {
    483					dev_warn(&port->dev,
    484						 "%s - status message too short\n",
    485						__func__);
    486					break;
    487				}
    488				qt2_process_status(port, ch + 2);
    489				i += 3;
    490				escapeflag = true;
    491				break;
    492			case QT2_XMIT_HOLD:
    493				if (i > (len - 5)) {
    494					dev_warn(&port->dev,
    495						 "%s - xmit_empty message too short\n",
    496						 __func__);
    497					break;
    498				}
    499				/* bytes_written = (ch[1] << 4) + ch[0]; */
    500				i += 4;
    501				escapeflag = true;
    502				break;
    503			case QT2_CHANGE_PORT:
    504				if (i > (len - 4)) {
    505					dev_warn(&port->dev,
    506						 "%s - change_port message too short\n",
    507						 __func__);
    508					break;
    509				}
    510				tty_flip_buffer_push(&port->port);
    511
    512				newport = *(ch + 3);
    513
    514				if (newport > serial->num_ports) {
    515					dev_err(&port->dev,
    516						"%s - port change to invalid port: %i\n",
    517						__func__, newport);
    518					break;
    519				}
    520
    521				serial_priv->current_port = newport;
    522				port = serial->port[serial_priv->current_port];
    523				i += 3;
    524				escapeflag = true;
    525				break;
    526			case QT2_REC_FLUSH:
    527			case QT2_XMIT_FLUSH:
    528				i += 2;
    529				escapeflag = true;
    530				break;
    531			case QT2_CONTROL_ESCAPE:
    532				tty_insert_flip_string(&port->port, ch, 2);
    533				i += 2;
    534				escapeflag = true;
    535				break;
    536			default:
    537				dev_warn(&port->dev,
    538					 "%s - unsupported command %i\n",
    539					 __func__, *(ch + 2));
    540				break;
    541			}
    542			if (escapeflag)
    543				continue;
    544		}
    545
    546		tty_insert_flip_char(&port->port, *ch, TTY_NORMAL);
    547	}
    548
    549	tty_flip_buffer_push(&port->port);
    550}
    551
    552static void qt2_write_bulk_callback(struct urb *urb)
    553{
    554	struct usb_serial_port *port;
    555	struct qt2_port_private *port_priv;
    556	unsigned long flags;
    557
    558	port = urb->context;
    559	port_priv = usb_get_serial_port_data(port);
    560
    561	spin_lock_irqsave(&port_priv->urb_lock, flags);
    562
    563	port_priv->urb_in_use = false;
    564	usb_serial_port_softint(port);
    565
    566	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
    567
    568}
    569
    570static void qt2_read_bulk_callback(struct urb *urb)
    571{
    572	struct usb_serial *serial = urb->context;
    573	int status;
    574
    575	if (urb->status) {
    576		dev_warn(&serial->dev->dev,
    577			 "%s - non-zero urb status: %i\n", __func__,
    578			 urb->status);
    579		return;
    580	}
    581
    582	qt2_process_read_urb(urb);
    583
    584	status = usb_submit_urb(urb, GFP_ATOMIC);
    585	if (status != 0)
    586		dev_err(&serial->dev->dev,
    587			"%s - resubmit read urb failed: %i\n",
    588			__func__, status);
    589}
    590
    591static int qt2_setup_urbs(struct usb_serial *serial)
    592{
    593	struct usb_serial_port *port0;
    594	struct qt2_serial_private *serial_priv;
    595	int status;
    596
    597	port0 = serial->port[0];
    598
    599	serial_priv = usb_get_serial_data(serial);
    600	serial_priv->read_urb = usb_alloc_urb(0, GFP_KERNEL);
    601	if (!serial_priv->read_urb)
    602		return -ENOMEM;
    603
    604	usb_fill_bulk_urb(serial_priv->read_urb, serial->dev,
    605			  usb_rcvbulkpipe(serial->dev,
    606					  port0->bulk_in_endpointAddress),
    607			  serial_priv->read_buffer,
    608			  QT2_READ_BUFFER_SIZE,
    609			  qt2_read_bulk_callback, serial);
    610
    611	status = usb_submit_urb(serial_priv->read_urb, GFP_KERNEL);
    612	if (status != 0) {
    613		dev_err(&serial->dev->dev,
    614			"%s - submit read urb failed %i\n", __func__, status);
    615		usb_free_urb(serial_priv->read_urb);
    616		return status;
    617	}
    618
    619	return 0;
    620}
    621
    622static int qt2_attach(struct usb_serial *serial)
    623{
    624	struct qt2_serial_private *serial_priv;
    625	int status;
    626
    627	/* power on unit */
    628	status = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
    629				 0xc2, 0x40, 0x8000, 0, NULL, 0,
    630				 QT2_USB_TIMEOUT);
    631	if (status < 0) {
    632		dev_err(&serial->dev->dev,
    633			"%s - failed to power on unit: %i\n", __func__, status);
    634		return status;
    635	}
    636
    637	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
    638	if (!serial_priv)
    639		return -ENOMEM;
    640
    641	serial_priv->read_buffer = kmalloc(QT2_READ_BUFFER_SIZE, GFP_KERNEL);
    642	if (!serial_priv->read_buffer) {
    643		status = -ENOMEM;
    644		goto err_buf;
    645	}
    646
    647	usb_set_serial_data(serial, serial_priv);
    648
    649	status = qt2_setup_urbs(serial);
    650	if (status != 0)
    651		goto attach_failed;
    652
    653	return 0;
    654
    655attach_failed:
    656	kfree(serial_priv->read_buffer);
    657err_buf:
    658	kfree(serial_priv);
    659	return status;
    660}
    661
    662static int qt2_port_probe(struct usb_serial_port *port)
    663{
    664	struct usb_serial *serial = port->serial;
    665	struct qt2_port_private *port_priv;
    666	u8 bEndpointAddress;
    667
    668	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
    669	if (!port_priv)
    670		return -ENOMEM;
    671
    672	spin_lock_init(&port_priv->lock);
    673	spin_lock_init(&port_priv->urb_lock);
    674	port_priv->port = port;
    675
    676	port_priv->write_buffer = kmalloc(QT2_WRITE_BUFFER_SIZE, GFP_KERNEL);
    677	if (!port_priv->write_buffer)
    678		goto err_buf;
    679
    680	port_priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
    681	if (!port_priv->write_urb)
    682		goto err_urb;
    683
    684	bEndpointAddress = serial->port[0]->bulk_out_endpointAddress;
    685	usb_fill_bulk_urb(port_priv->write_urb, serial->dev,
    686				usb_sndbulkpipe(serial->dev, bEndpointAddress),
    687				port_priv->write_buffer,
    688				QT2_WRITE_BUFFER_SIZE,
    689				qt2_write_bulk_callback, port);
    690
    691	usb_set_serial_port_data(port, port_priv);
    692
    693	return 0;
    694err_urb:
    695	kfree(port_priv->write_buffer);
    696err_buf:
    697	kfree(port_priv);
    698	return -ENOMEM;
    699}
    700
    701static void qt2_port_remove(struct usb_serial_port *port)
    702{
    703	struct qt2_port_private *port_priv;
    704
    705	port_priv = usb_get_serial_port_data(port);
    706	usb_free_urb(port_priv->write_urb);
    707	kfree(port_priv->write_buffer);
    708	kfree(port_priv);
    709}
    710
    711static int qt2_tiocmget(struct tty_struct *tty)
    712{
    713	struct usb_serial_port *port = tty->driver_data;
    714	struct usb_device *dev = port->serial->dev;
    715	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
    716	u8 *d;
    717	int r;
    718
    719	d = kzalloc(2, GFP_KERNEL);
    720	if (!d)
    721		return -ENOMEM;
    722
    723	r = qt2_getregister(dev, port_priv->device_port, UART_MCR, d);
    724	if (r < 0)
    725		goto mget_out;
    726
    727	r = qt2_getregister(dev, port_priv->device_port, UART_MSR, d + 1);
    728	if (r < 0)
    729		goto mget_out;
    730
    731	r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
    732	    (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
    733	    (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
    734	    (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
    735	    (d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
    736	    (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
    737
    738mget_out:
    739	kfree(d);
    740	return r;
    741}
    742
    743static int qt2_tiocmset(struct tty_struct *tty,
    744			unsigned int set, unsigned int clear)
    745{
    746	struct qt2_port_private *port_priv;
    747
    748	port_priv = usb_get_serial_port_data(tty->driver_data);
    749	return update_mctrl(port_priv, set, clear);
    750}
    751
    752static void qt2_break_ctl(struct tty_struct *tty, int break_state)
    753{
    754	struct usb_serial_port *port = tty->driver_data;
    755	struct qt2_port_private *port_priv;
    756	int status;
    757	u16 val;
    758
    759	port_priv = usb_get_serial_port_data(port);
    760
    761	val = (break_state == -1) ? 1 : 0;
    762
    763	status = qt2_control_msg(port->serial->dev, QT2_BREAK_CONTROL,
    764				 val, port_priv->device_port);
    765	if (status < 0)
    766		dev_warn(&port->dev,
    767			 "%s - failed to send control message: %i\n", __func__,
    768			 status);
    769}
    770
    771
    772
    773static void qt2_dtr_rts(struct usb_serial_port *port, int on)
    774{
    775	struct usb_device *dev = port->serial->dev;
    776	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
    777
    778	/* Disable flow control */
    779	if (!on) {
    780		if (qt2_setregister(dev, port_priv->device_port,
    781					   UART_MCR, 0) < 0)
    782			dev_warn(&port->dev, "error from flowcontrol urb\n");
    783	}
    784	/* drop RTS and DTR */
    785	if (on)
    786		update_mctrl(port_priv, TIOCM_DTR | TIOCM_RTS, 0);
    787	else
    788		update_mctrl(port_priv, 0, TIOCM_DTR | TIOCM_RTS);
    789}
    790
    791static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch)
    792{
    793	struct qt2_port_private *port_priv;
    794	u8 newMSR = (u8) *ch;
    795	unsigned long flags;
    796
    797	/* May be called from qt2_process_read_urb() for an unbound port. */
    798	port_priv = usb_get_serial_port_data(port);
    799	if (!port_priv)
    800		return;
    801
    802	spin_lock_irqsave(&port_priv->lock, flags);
    803	port_priv->shadowMSR = newMSR;
    804	spin_unlock_irqrestore(&port_priv->lock, flags);
    805
    806	if (newMSR & UART_MSR_ANY_DELTA) {
    807		/* update input line counters */
    808		if (newMSR & UART_MSR_DCTS)
    809			port->icount.cts++;
    810		if (newMSR & UART_MSR_DDSR)
    811			port->icount.dsr++;
    812		if (newMSR & UART_MSR_DDCD)
    813			port->icount.dcd++;
    814		if (newMSR & UART_MSR_TERI)
    815			port->icount.rng++;
    816
    817		wake_up_interruptible(&port->port.delta_msr_wait);
    818	}
    819}
    820
    821static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch)
    822{
    823	struct qt2_port_private *port_priv;
    824	struct async_icount *icount;
    825	unsigned long flags;
    826	u8 newLSR = (u8) *ch;
    827
    828	/* May be called from qt2_process_read_urb() for an unbound port. */
    829	port_priv = usb_get_serial_port_data(port);
    830	if (!port_priv)
    831		return;
    832
    833	if (newLSR & UART_LSR_BI)
    834		newLSR &= (u8) (UART_LSR_OE | UART_LSR_BI);
    835
    836	spin_lock_irqsave(&port_priv->lock, flags);
    837	port_priv->shadowLSR = newLSR;
    838	spin_unlock_irqrestore(&port_priv->lock, flags);
    839
    840	icount = &port->icount;
    841
    842	if (newLSR & UART_LSR_BRK_ERROR_BITS) {
    843
    844		if (newLSR & UART_LSR_BI)
    845			icount->brk++;
    846
    847		if (newLSR & UART_LSR_OE)
    848			icount->overrun++;
    849
    850		if (newLSR & UART_LSR_PE)
    851			icount->parity++;
    852
    853		if (newLSR & UART_LSR_FE)
    854			icount->frame++;
    855	}
    856
    857}
    858
    859static unsigned int qt2_write_room(struct tty_struct *tty)
    860{
    861	struct usb_serial_port *port = tty->driver_data;
    862	struct qt2_port_private *port_priv;
    863	unsigned long flags;
    864	unsigned int r;
    865
    866	port_priv = usb_get_serial_port_data(port);
    867
    868	spin_lock_irqsave(&port_priv->urb_lock, flags);
    869
    870	if (port_priv->urb_in_use)
    871		r = 0;
    872	else
    873		r = QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE;
    874
    875	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
    876
    877	return r;
    878}
    879
    880static int qt2_write(struct tty_struct *tty,
    881		     struct usb_serial_port *port,
    882		     const unsigned char *buf, int count)
    883{
    884	struct qt2_port_private *port_priv;
    885	struct urb *write_urb;
    886	unsigned char *data;
    887	unsigned long flags;
    888	int status;
    889	int bytes_out = 0;
    890
    891	port_priv = usb_get_serial_port_data(port);
    892
    893	if (port_priv->write_urb == NULL) {
    894		dev_err(&port->dev, "%s - no output urb\n", __func__);
    895		return 0;
    896	}
    897	write_urb = port_priv->write_urb;
    898
    899	count = min(count, QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE);
    900
    901	data = write_urb->transfer_buffer;
    902	spin_lock_irqsave(&port_priv->urb_lock, flags);
    903	if (port_priv->urb_in_use) {
    904		dev_err(&port->dev, "qt2_write - urb is in use\n");
    905		goto write_out;
    906	}
    907
    908	*data++ = QT2_CONTROL_BYTE;
    909	*data++ = QT2_CONTROL_BYTE;
    910	*data++ = port_priv->device_port;
    911	put_unaligned_le16(count, data);
    912	data += 2;
    913	memcpy(data, buf, count);
    914
    915	write_urb->transfer_buffer_length = count + QT2_WRITE_CONTROL_SIZE;
    916
    917	status = usb_submit_urb(write_urb, GFP_ATOMIC);
    918	if (status == 0) {
    919		port_priv->urb_in_use = true;
    920		bytes_out += count;
    921	}
    922
    923write_out:
    924	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
    925	return bytes_out;
    926}
    927
    928
    929static struct usb_serial_driver qt2_device = {
    930	.driver = {
    931		.owner = THIS_MODULE,
    932		.name = "quatech-serial",
    933	},
    934	.description	     = DRIVER_DESC,
    935	.id_table	     = id_table,
    936	.open		     = qt2_open,
    937	.close		     = qt2_close,
    938	.write               = qt2_write,
    939	.write_room          = qt2_write_room,
    940	.calc_num_ports      = qt2_calc_num_ports,
    941	.attach              = qt2_attach,
    942	.release             = qt2_release,
    943	.disconnect          = qt2_disconnect,
    944	.port_probe          = qt2_port_probe,
    945	.port_remove         = qt2_port_remove,
    946	.dtr_rts             = qt2_dtr_rts,
    947	.break_ctl           = qt2_break_ctl,
    948	.tiocmget            = qt2_tiocmget,
    949	.tiocmset            = qt2_tiocmset,
    950	.tiocmiwait          = usb_serial_generic_tiocmiwait,
    951	.get_icount	     = usb_serial_generic_get_icount,
    952	.set_termios         = qt2_set_termios,
    953};
    954
    955static struct usb_serial_driver *const serial_drivers[] = {
    956	&qt2_device, NULL
    957};
    958
    959module_usb_serial_driver(serial_drivers, id_table);
    960
    961MODULE_DESCRIPTION(DRIVER_DESC);
    962MODULE_LICENSE("GPL v2");