xref: /linux/drivers/usb/serial/mxuport.c (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
1 /*
2  *	mxuport.c - MOXA UPort series driver
3  *
4  *	Copyright (c) 2006 Moxa Technologies Co., Ltd.
5  *	Copyright (c) 2013 Andrew Lunn <andrew@lunn.ch>
6  *
7  *	This program is free software; you can redistribute it and/or modify
8  *	it under the terms of the GNU General Public License as published by
9  *	the Free Software Foundation; either version 2 of the License, or
10  *	(at your option) any later version.
11  *
12  *	Supports the following Moxa USB to serial converters:
13  *	 2 ports : UPort 1250, UPort 1250I
14  *	 4 ports : UPort 1410, UPort 1450, UPort 1450I
15  *	 8 ports : UPort 1610-8, UPort 1650-8
16  *	16 ports : UPort 1610-16, UPort 1650-16
17  */
18 
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/firmware.h>
22 #include <linux/jiffies.h>
23 #include <linux/serial.h>
24 #include <linux/serial_reg.h>
25 #include <linux/slab.h>
26 #include <linux/tty.h>
27 #include <linux/tty_driver.h>
28 #include <linux/tty_flip.h>
29 #include <linux/uaccess.h>
30 #include <linux/usb.h>
31 #include <linux/usb/serial.h>
32 #include <asm/unaligned.h>
33 
34 /* Definitions for the vendor ID and device ID */
35 #define MX_USBSERIAL_VID	0x110A
36 #define MX_UPORT1250_PID	0x1250
37 #define MX_UPORT1251_PID	0x1251
38 #define MX_UPORT1410_PID	0x1410
39 #define MX_UPORT1450_PID	0x1450
40 #define MX_UPORT1451_PID	0x1451
41 #define MX_UPORT1618_PID	0x1618
42 #define MX_UPORT1658_PID	0x1658
43 #define MX_UPORT1613_PID	0x1613
44 #define MX_UPORT1653_PID	0x1653
45 
46 /* Definitions for USB info */
47 #define HEADER_SIZE		4
48 #define EVENT_LENGTH		8
49 #define DOWN_BLOCK_SIZE		64
50 
51 /* Definitions for firmware info */
52 #define VER_ADDR_1		0x20
53 #define VER_ADDR_2		0x24
54 #define VER_ADDR_3		0x28
55 
56 /* Definitions for USB vendor request */
57 #define RQ_VENDOR_NONE			0x00
58 #define RQ_VENDOR_SET_BAUD		0x01 /* Set baud rate */
59 #define RQ_VENDOR_SET_LINE		0x02 /* Set line status */
60 #define RQ_VENDOR_SET_CHARS		0x03 /* Set Xon/Xoff chars */
61 #define RQ_VENDOR_SET_RTS		0x04 /* Set RTS */
62 #define RQ_VENDOR_SET_DTR		0x05 /* Set DTR */
63 #define RQ_VENDOR_SET_XONXOFF		0x06 /* Set auto Xon/Xoff */
64 #define RQ_VENDOR_SET_RX_HOST_EN	0x07 /* Set RX host enable */
65 #define RQ_VENDOR_SET_OPEN		0x08 /* Set open/close port */
66 #define RQ_VENDOR_PURGE			0x09 /* Purge Rx/Tx buffer */
67 #define RQ_VENDOR_SET_MCR		0x0A /* Set MCR register */
68 #define RQ_VENDOR_SET_BREAK		0x0B /* Set Break signal */
69 
70 #define RQ_VENDOR_START_FW_DOWN		0x0C /* Start firmware download */
71 #define RQ_VENDOR_STOP_FW_DOWN		0x0D /* Stop firmware download */
72 #define RQ_VENDOR_QUERY_FW_READY	0x0E /* Query if new firmware ready */
73 
74 #define RQ_VENDOR_SET_FIFO_DISABLE	0x0F /* Set fifo disable */
75 #define RQ_VENDOR_SET_INTERFACE		0x10 /* Set interface */
76 #define RQ_VENDOR_SET_HIGH_PERFOR	0x11 /* Set hi-performance */
77 
78 #define RQ_VENDOR_ERASE_BLOCK		0x12 /* Erase flash block */
79 #define RQ_VENDOR_WRITE_PAGE		0x13 /* Write flash page */
80 #define RQ_VENDOR_PREPARE_WRITE		0x14 /* Prepare write flash */
81 #define RQ_VENDOR_CONFIRM_WRITE		0x15 /* Confirm write flash */
82 #define RQ_VENDOR_LOCATE		0x16 /* Locate the device */
83 
84 #define RQ_VENDOR_START_ROM_DOWN	0x17 /* Start firmware download */
85 #define RQ_VENDOR_ROM_DATA		0x18 /* Rom file data */
86 #define RQ_VENDOR_STOP_ROM_DOWN		0x19 /* Stop firmware download */
87 #define RQ_VENDOR_FW_DATA		0x20 /* Firmware data */
88 
89 #define RQ_VENDOR_RESET_DEVICE		0x23 /* Try to reset the device */
90 #define RQ_VENDOR_QUERY_FW_CONFIG	0x24
91 
92 #define RQ_VENDOR_GET_VERSION		0x81 /* Get firmware version */
93 #define RQ_VENDOR_GET_PAGE		0x82 /* Read flash page */
94 #define RQ_VENDOR_GET_ROM_PROC		0x83 /* Get ROM process state */
95 
96 #define RQ_VENDOR_GET_INQUEUE		0x84 /* Data in input buffer */
97 #define RQ_VENDOR_GET_OUTQUEUE		0x85 /* Data in output buffer */
98 
99 #define RQ_VENDOR_GET_MSR		0x86 /* Get modem status register */
100 
101 /* Definitions for UPort event type */
102 #define UPORT_EVENT_NONE		0 /* None */
103 #define UPORT_EVENT_TXBUF_THRESHOLD	1 /* Tx buffer threshold */
104 #define UPORT_EVENT_SEND_NEXT		2 /* Send next */
105 #define UPORT_EVENT_MSR			3 /* Modem status */
106 #define UPORT_EVENT_LSR			4 /* Line status */
107 #define UPORT_EVENT_MCR			5 /* Modem control */
108 
109 /* Definitions for serial event type */
110 #define SERIAL_EV_CTS			0x0008	/* CTS changed state */
111 #define SERIAL_EV_DSR			0x0010	/* DSR changed state */
112 #define SERIAL_EV_RLSD			0x0020	/* RLSD changed state */
113 
114 /* Definitions for modem control event type */
115 #define SERIAL_EV_XOFF			0x40	/* XOFF received */
116 
117 /* Definitions for line control of communication */
118 #define MX_WORDLENGTH_5			5
119 #define MX_WORDLENGTH_6			6
120 #define MX_WORDLENGTH_7			7
121 #define MX_WORDLENGTH_8			8
122 
123 #define MX_PARITY_NONE			0
124 #define MX_PARITY_ODD			1
125 #define MX_PARITY_EVEN			2
126 #define MX_PARITY_MARK			3
127 #define MX_PARITY_SPACE			4
128 
129 #define MX_STOP_BITS_1			0
130 #define MX_STOP_BITS_1_5		1
131 #define MX_STOP_BITS_2			2
132 
133 #define MX_RTS_DISABLE			0x0
134 #define MX_RTS_ENABLE			0x1
135 #define MX_RTS_HW			0x2
136 #define MX_RTS_NO_CHANGE		0x3 /* Flag, not valid register value*/
137 
138 #define MX_INT_RS232			0
139 #define MX_INT_2W_RS485			1
140 #define MX_INT_RS422			2
141 #define MX_INT_4W_RS485			3
142 
143 /* Definitions for holding reason */
144 #define MX_WAIT_FOR_CTS			0x0001
145 #define MX_WAIT_FOR_DSR			0x0002
146 #define MX_WAIT_FOR_DCD			0x0004
147 #define MX_WAIT_FOR_XON			0x0008
148 #define MX_WAIT_FOR_START_TX		0x0010
149 #define MX_WAIT_FOR_UNTHROTTLE		0x0020
150 #define MX_WAIT_FOR_LOW_WATER		0x0040
151 #define MX_WAIT_FOR_SEND_NEXT		0x0080
152 
153 #define MX_UPORT_2_PORT			BIT(0)
154 #define MX_UPORT_4_PORT			BIT(1)
155 #define MX_UPORT_8_PORT			BIT(2)
156 #define MX_UPORT_16_PORT		BIT(3)
157 
158 /* This structure holds all of the local port information */
159 struct mxuport_port {
160 	u8 mcr_state;		/* Last MCR state */
161 	u8 msr_state;		/* Last MSR state */
162 	struct mutex mutex;	/* Protects mcr_state */
163 	spinlock_t spinlock;	/* Protects msr_state */
164 };
165 
166 /* Table of devices that work with this driver */
167 static const struct usb_device_id mxuport_idtable[] = {
168 	{ USB_DEVICE(MX_USBSERIAL_VID, MX_UPORT1250_PID),
169 	  .driver_info = MX_UPORT_2_PORT },
170 	{ USB_DEVICE(MX_USBSERIAL_VID, MX_UPORT1251_PID),
171 	  .driver_info = MX_UPORT_2_PORT },
172 	{ USB_DEVICE(MX_USBSERIAL_VID, MX_UPORT1410_PID),
173 	  .driver_info = MX_UPORT_4_PORT },
174 	{ USB_DEVICE(MX_USBSERIAL_VID, MX_UPORT1450_PID),
175 	  .driver_info = MX_UPORT_4_PORT },
176 	{ USB_DEVICE(MX_USBSERIAL_VID, MX_UPORT1451_PID),
177 	  .driver_info = MX_UPORT_4_PORT },
178 	{ USB_DEVICE(MX_USBSERIAL_VID, MX_UPORT1618_PID),
179 	  .driver_info = MX_UPORT_8_PORT },
180 	{ USB_DEVICE(MX_USBSERIAL_VID, MX_UPORT1658_PID),
181 	  .driver_info = MX_UPORT_8_PORT },
182 	{ USB_DEVICE(MX_USBSERIAL_VID, MX_UPORT1613_PID),
183 	  .driver_info = MX_UPORT_16_PORT },
184 	{ USB_DEVICE(MX_USBSERIAL_VID, MX_UPORT1653_PID),
185 	  .driver_info = MX_UPORT_16_PORT },
186 	{}			/* Terminating entry */
187 };
188 
189 MODULE_DEVICE_TABLE(usb, mxuport_idtable);
190 
191 /*
192  * Add a four byte header containing the port number and the number of
193  * bytes of data in the message. Return the number of bytes in the
194  * buffer.
195  */
196 static int mxuport_prepare_write_buffer(struct usb_serial_port *port,
197 					void *dest, size_t size)
198 {
199 	u8 *buf = dest;
200 	int count;
201 
202 	count = kfifo_out_locked(&port->write_fifo, buf + HEADER_SIZE,
203 				 size - HEADER_SIZE,
204 				 &port->lock);
205 
206 	put_unaligned_be16(port->port_number, buf);
207 	put_unaligned_be16(count, buf + 2);
208 
209 	dev_dbg(&port->dev, "%s - size %zd count %d\n", __func__,
210 		size, count);
211 
212 	return count + HEADER_SIZE;
213 }
214 
215 /* Read the given buffer in from the control pipe. */
216 static int mxuport_recv_ctrl_urb(struct usb_serial *serial,
217 				 u8 request, u16 value, u16 index,
218 				 u8 *data, size_t size)
219 {
220 	int status;
221 
222 	status = usb_control_msg(serial->dev,
223 				 usb_rcvctrlpipe(serial->dev, 0),
224 				 request,
225 				 (USB_DIR_IN | USB_TYPE_VENDOR |
226 				  USB_RECIP_DEVICE), value, index,
227 				 data, size,
228 				 USB_CTRL_GET_TIMEOUT);
229 	if (status < 0) {
230 		dev_err(&serial->interface->dev,
231 			"%s - usb_control_msg failed (%d)\n",
232 			__func__, status);
233 		return status;
234 	}
235 
236 	if (status != size) {
237 		dev_err(&serial->interface->dev,
238 			"%s - short read (%d / %zd)\n",
239 			__func__, status, size);
240 		return -EIO;
241 	}
242 
243 	return status;
244 }
245 
246 /* Write the given buffer out to the control pipe.  */
247 static int mxuport_send_ctrl_data_urb(struct usb_serial *serial,
248 				      u8 request,
249 				      u16 value, u16 index,
250 				      u8 *data, size_t size)
251 {
252 	int status;
253 
254 	status = usb_control_msg(serial->dev,
255 				 usb_sndctrlpipe(serial->dev, 0),
256 				 request,
257 				 (USB_DIR_OUT | USB_TYPE_VENDOR |
258 				  USB_RECIP_DEVICE), value, index,
259 				 data, size,
260 				 USB_CTRL_SET_TIMEOUT);
261 	if (status < 0) {
262 		dev_err(&serial->interface->dev,
263 			"%s - usb_control_msg failed (%d)\n",
264 			__func__, status);
265 		return status;
266 	}
267 
268 	if (status != size) {
269 		dev_err(&serial->interface->dev,
270 			"%s - short write (%d / %zd)\n",
271 			__func__, status, size);
272 		return -EIO;
273 	}
274 
275 	return 0;
276 }
277 
278 /* Send a vendor request without any data */
279 static int mxuport_send_ctrl_urb(struct usb_serial *serial,
280 				 u8 request, u16 value, u16 index)
281 {
282 	return mxuport_send_ctrl_data_urb(serial, request, value, index,
283 					  NULL, 0);
284 }
285 
286 /*
287  * mxuport_throttle - throttle function of driver
288  *
289  * This function is called by the tty driver when it wants to stop the
290  * data being read from the port. Since all the data comes over one
291  * bulk in endpoint, we cannot stop submitting urbs by setting
292  * port->throttle. Instead tell the device to stop sending us data for
293  * the port.
294  */
295 static void mxuport_throttle(struct tty_struct *tty)
296 {
297 	struct usb_serial_port *port = tty->driver_data;
298 	struct usb_serial *serial = port->serial;
299 
300 	dev_dbg(&port->dev, "%s\n", __func__);
301 
302 	mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_RX_HOST_EN,
303 			      0, port->port_number);
304 }
305 
306 /*
307  * mxuport_unthrottle - unthrottle function of driver
308  *
309  * This function is called by the tty driver when it wants to resume
310  * the data being read from the port. Tell the device it can resume
311  * sending us received data from the port.
312  */
313 static void mxuport_unthrottle(struct tty_struct *tty)
314 {
315 
316 	struct usb_serial_port *port = tty->driver_data;
317 	struct usb_serial *serial = port->serial;
318 
319 	dev_dbg(&port->dev, "%s\n", __func__);
320 
321 	mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_RX_HOST_EN,
322 			      1, port->port_number);
323 }
324 
325 /*
326  * Processes one chunk of data received for a port.  Mostly a copy of
327  * usb_serial_generic_process_read_urb().
328  */
329 static void mxuport_process_read_urb_data(struct usb_serial_port *port,
330 					  char *data, int size)
331 {
332 	int i;
333 
334 	if (!port->port.console || !port->sysrq) {
335 		tty_insert_flip_string(&port->port, data, size);
336 	} else {
337 		for (i = 0; i < size; i++, data++) {
338 			if (!usb_serial_handle_sysrq_char(port, *data))
339 				tty_insert_flip_char(&port->port, *data,
340 						     TTY_NORMAL);
341 		}
342 	}
343 	tty_flip_buffer_push(&port->port);
344 }
345 
346 static void mxuport_msr_event(struct usb_serial_port *port, u8 buf[4])
347 {
348 	struct mxuport_port *mxport = usb_get_serial_port_data(port);
349 	u8 rcv_msr_hold = buf[2] & 0xF0;
350 	u16 rcv_msr_event = get_unaligned_be16(buf);
351 	unsigned long flags;
352 
353 	if (rcv_msr_event == 0)
354 		return;
355 
356 	/* Update MSR status */
357 	spin_lock_irqsave(&mxport->spinlock, flags);
358 
359 	dev_dbg(&port->dev, "%s - current MSR status = 0x%x\n",
360 		__func__, mxport->msr_state);
361 
362 	if (rcv_msr_hold & UART_MSR_CTS) {
363 		mxport->msr_state |= UART_MSR_CTS;
364 		dev_dbg(&port->dev, "%s - CTS high\n", __func__);
365 	} else {
366 		mxport->msr_state &= ~UART_MSR_CTS;
367 		dev_dbg(&port->dev, "%s - CTS low\n", __func__);
368 	}
369 
370 	if (rcv_msr_hold & UART_MSR_DSR) {
371 		mxport->msr_state |= UART_MSR_DSR;
372 		dev_dbg(&port->dev, "%s - DSR high\n", __func__);
373 	} else {
374 		mxport->msr_state &= ~UART_MSR_DSR;
375 		dev_dbg(&port->dev, "%s - DSR low\n", __func__);
376 	}
377 
378 	if (rcv_msr_hold & UART_MSR_DCD) {
379 		mxport->msr_state |= UART_MSR_DCD;
380 		dev_dbg(&port->dev, "%s - DCD high\n", __func__);
381 	} else {
382 		mxport->msr_state &= ~UART_MSR_DCD;
383 		dev_dbg(&port->dev, "%s - DCD low\n", __func__);
384 	}
385 	spin_unlock_irqrestore(&mxport->spinlock, flags);
386 
387 	if (rcv_msr_event &
388 	    (SERIAL_EV_CTS | SERIAL_EV_DSR | SERIAL_EV_RLSD)) {
389 
390 		if (rcv_msr_event & SERIAL_EV_CTS) {
391 			port->icount.cts++;
392 			dev_dbg(&port->dev, "%s - CTS change\n", __func__);
393 		}
394 
395 		if (rcv_msr_event & SERIAL_EV_DSR) {
396 			port->icount.dsr++;
397 			dev_dbg(&port->dev, "%s - DSR change\n", __func__);
398 		}
399 
400 		if (rcv_msr_event & SERIAL_EV_RLSD) {
401 			port->icount.dcd++;
402 			dev_dbg(&port->dev, "%s - DCD change\n", __func__);
403 		}
404 		wake_up_interruptible(&port->port.delta_msr_wait);
405 	}
406 }
407 
408 static void mxuport_lsr_event(struct usb_serial_port *port, u8 buf[4])
409 {
410 	u8 lsr_event = buf[2];
411 
412 	if (lsr_event & UART_LSR_BI) {
413 		port->icount.brk++;
414 		dev_dbg(&port->dev, "%s - break error\n", __func__);
415 	}
416 
417 	if (lsr_event & UART_LSR_FE) {
418 		port->icount.frame++;
419 		dev_dbg(&port->dev, "%s - frame error\n", __func__);
420 	}
421 
422 	if (lsr_event & UART_LSR_PE) {
423 		port->icount.parity++;
424 		dev_dbg(&port->dev, "%s - parity error\n", __func__);
425 	}
426 
427 	if (lsr_event & UART_LSR_OE) {
428 		port->icount.overrun++;
429 		dev_dbg(&port->dev, "%s - overrun error\n", __func__);
430 	}
431 }
432 
433 /*
434  * When something interesting happens, modem control lines XON/XOFF
435  * etc, the device sends an event. Process these events.
436  */
437 static void mxuport_process_read_urb_event(struct usb_serial_port *port,
438 					   u8 buf[4], u32 event)
439 {
440 	dev_dbg(&port->dev, "%s - receive event : %04x\n", __func__, event);
441 
442 	switch (event) {
443 	case UPORT_EVENT_SEND_NEXT:
444 		/*
445 		 * Sent as part of the flow control on device buffers.
446 		 * Not currently used.
447 		 */
448 		break;
449 	case UPORT_EVENT_MSR:
450 		mxuport_msr_event(port, buf);
451 		break;
452 	case UPORT_EVENT_LSR:
453 		mxuport_lsr_event(port, buf);
454 		break;
455 	case UPORT_EVENT_MCR:
456 		/*
457 		 * Event to indicate a change in XON/XOFF from the
458 		 * peer.  Currently not used. We just continue
459 		 * sending the device data and it will buffer it if
460 		 * needed. This event could be used for flow control
461 		 * between the host and the device.
462 		 */
463 		break;
464 	default:
465 		dev_dbg(&port->dev, "Unexpected event\n");
466 		break;
467 	}
468 }
469 
470 /*
471  * One URB can contain data for multiple ports. Demultiplex the data,
472  * checking the port exists, is opened and the message is valid.
473  */
474 static void mxuport_process_read_urb_demux_data(struct urb *urb)
475 {
476 	struct usb_serial_port *port = urb->context;
477 	struct usb_serial *serial = port->serial;
478 	u8 *data = urb->transfer_buffer;
479 	u8 *end = data + urb->actual_length;
480 	struct usb_serial_port *demux_port;
481 	u8 *ch;
482 	u16 rcv_port;
483 	u16 rcv_len;
484 
485 	while (data < end) {
486 		if (data + HEADER_SIZE > end) {
487 			dev_warn(&port->dev, "%s - message with short header\n",
488 				 __func__);
489 			return;
490 		}
491 
492 		rcv_port = get_unaligned_be16(data);
493 		if (rcv_port >= serial->num_ports) {
494 			dev_warn(&port->dev, "%s - message for invalid port\n",
495 				 __func__);
496 			return;
497 		}
498 
499 		demux_port = serial->port[rcv_port];
500 		rcv_len = get_unaligned_be16(data + 2);
501 		if (!rcv_len || data + HEADER_SIZE + rcv_len > end) {
502 			dev_warn(&port->dev, "%s - short data\n", __func__);
503 			return;
504 		}
505 
506 		if (test_bit(ASYNCB_INITIALIZED, &demux_port->port.flags)) {
507 			ch = data + HEADER_SIZE;
508 			mxuport_process_read_urb_data(demux_port, ch, rcv_len);
509 		} else {
510 			dev_dbg(&demux_port->dev, "%s - data for closed port\n",
511 				__func__);
512 		}
513 		data += HEADER_SIZE + rcv_len;
514 	}
515 }
516 
517 /*
518  * One URB can contain events for multiple ports. Demultiplex the event,
519  * checking the port exists, and is opened.
520  */
521 static void mxuport_process_read_urb_demux_event(struct urb *urb)
522 {
523 	struct usb_serial_port *port = urb->context;
524 	struct usb_serial *serial = port->serial;
525 	u8 *data = urb->transfer_buffer;
526 	u8 *end = data + urb->actual_length;
527 	struct usb_serial_port *demux_port;
528 	u8 *ch;
529 	u16 rcv_port;
530 	u16 rcv_event;
531 
532 	while (data < end) {
533 		if (data + EVENT_LENGTH > end) {
534 			dev_warn(&port->dev, "%s - message with short event\n",
535 				 __func__);
536 			return;
537 		}
538 
539 		rcv_port = get_unaligned_be16(data);
540 		if (rcv_port >= serial->num_ports) {
541 			dev_warn(&port->dev, "%s - message for invalid port\n",
542 				 __func__);
543 			return;
544 		}
545 
546 		demux_port = serial->port[rcv_port];
547 		if (test_bit(ASYNCB_INITIALIZED, &demux_port->port.flags)) {
548 			ch = data + HEADER_SIZE;
549 			rcv_event = get_unaligned_be16(data + 2);
550 			mxuport_process_read_urb_event(demux_port, ch,
551 						       rcv_event);
552 		} else {
553 			dev_dbg(&demux_port->dev,
554 				"%s - event for closed port\n", __func__);
555 		}
556 		data += EVENT_LENGTH;
557 	}
558 }
559 
560 /*
561  * This is called when we have received data on the bulk in
562  * endpoint. Depending on which port it was received on, it can
563  * contain serial data or events.
564  */
565 static void mxuport_process_read_urb(struct urb *urb)
566 {
567 	struct usb_serial_port *port = urb->context;
568 	struct usb_serial *serial = port->serial;
569 
570 	if (port == serial->port[0])
571 		mxuport_process_read_urb_demux_data(urb);
572 
573 	if (port == serial->port[1])
574 		mxuport_process_read_urb_demux_event(urb);
575 }
576 
577 /*
578  * Ask the device how many bytes it has queued to be sent out. If
579  * there are none, return true.
580  */
581 static bool mxuport_tx_empty(struct usb_serial_port *port)
582 {
583 	struct usb_serial *serial = port->serial;
584 	bool is_empty = true;
585 	u32 txlen;
586 	u8 *len_buf;
587 	int err;
588 
589 	len_buf = kzalloc(4, GFP_KERNEL);
590 	if (!len_buf)
591 		goto out;
592 
593 	err = mxuport_recv_ctrl_urb(serial, RQ_VENDOR_GET_OUTQUEUE, 0,
594 				    port->port_number, len_buf, 4);
595 	if (err < 0)
596 		goto out;
597 
598 	txlen = get_unaligned_be32(len_buf);
599 	dev_dbg(&port->dev, "%s - tx len = %u\n", __func__, txlen);
600 
601 	if (txlen != 0)
602 		is_empty = false;
603 
604 out:
605 	kfree(len_buf);
606 	return is_empty;
607 }
608 
609 static int mxuport_set_mcr(struct usb_serial_port *port, u8 mcr_state)
610 {
611 	struct usb_serial *serial = port->serial;
612 	int err;
613 
614 	dev_dbg(&port->dev, "%s - %02x\n", __func__, mcr_state);
615 
616 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_MCR,
617 				    mcr_state, port->port_number);
618 	if (err)
619 		dev_err(&port->dev, "%s - failed to change MCR\n", __func__);
620 
621 	return err;
622 }
623 
624 static int mxuport_set_dtr(struct usb_serial_port *port, int on)
625 {
626 	struct mxuport_port *mxport = usb_get_serial_port_data(port);
627 	struct usb_serial *serial = port->serial;
628 	int err;
629 
630 	mutex_lock(&mxport->mutex);
631 
632 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_DTR,
633 				    !!on, port->port_number);
634 	if (!err) {
635 		if (on)
636 			mxport->mcr_state |= UART_MCR_DTR;
637 		else
638 			mxport->mcr_state &= ~UART_MCR_DTR;
639 	}
640 
641 	mutex_unlock(&mxport->mutex);
642 
643 	return err;
644 }
645 
646 static int mxuport_set_rts(struct usb_serial_port *port, u8 state)
647 {
648 	struct mxuport_port *mxport = usb_get_serial_port_data(port);
649 	struct usb_serial *serial = port->serial;
650 	int err;
651 	u8 mcr_state;
652 
653 	mutex_lock(&mxport->mutex);
654 	mcr_state = mxport->mcr_state;
655 
656 	switch (state) {
657 	case MX_RTS_DISABLE:
658 		mcr_state &= ~UART_MCR_RTS;
659 		break;
660 	case MX_RTS_ENABLE:
661 		mcr_state |= UART_MCR_RTS;
662 		break;
663 	case MX_RTS_HW:
664 		/*
665 		 * Do not update mxport->mcr_state when doing hardware
666 		 * flow control.
667 		 */
668 		break;
669 	default:
670 		/*
671 		 * Should not happen, but somebody might try passing
672 		 * MX_RTS_NO_CHANGE, which is not valid.
673 		 */
674 		err = -EINVAL;
675 		goto out;
676 	}
677 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_RTS,
678 				    state, port->port_number);
679 	if (!err)
680 		mxport->mcr_state = mcr_state;
681 
682 out:
683 	mutex_unlock(&mxport->mutex);
684 
685 	return err;
686 }
687 
688 static void mxuport_dtr_rts(struct usb_serial_port *port, int on)
689 {
690 	struct mxuport_port *mxport = usb_get_serial_port_data(port);
691 	u8 mcr_state;
692 	int err;
693 
694 	mutex_lock(&mxport->mutex);
695 	mcr_state = mxport->mcr_state;
696 
697 	if (on)
698 		mcr_state |= (UART_MCR_RTS | UART_MCR_DTR);
699 	else
700 		mcr_state &= ~(UART_MCR_RTS | UART_MCR_DTR);
701 
702 	err = mxuport_set_mcr(port, mcr_state);
703 	if (!err)
704 		mxport->mcr_state = mcr_state;
705 
706 	mutex_unlock(&mxport->mutex);
707 }
708 
709 static int mxuport_tiocmset(struct tty_struct *tty, unsigned int set,
710 			    unsigned int clear)
711 {
712 	struct usb_serial_port *port = tty->driver_data;
713 	struct mxuport_port *mxport = usb_get_serial_port_data(port);
714 	int err;
715 	u8 mcr_state;
716 
717 	mutex_lock(&mxport->mutex);
718 	mcr_state = mxport->mcr_state;
719 
720 	if (set & TIOCM_RTS)
721 		mcr_state |= UART_MCR_RTS;
722 
723 	if (set & TIOCM_DTR)
724 		mcr_state |= UART_MCR_DTR;
725 
726 	if (clear & TIOCM_RTS)
727 		mcr_state &= ~UART_MCR_RTS;
728 
729 	if (clear & TIOCM_DTR)
730 		mcr_state &= ~UART_MCR_DTR;
731 
732 	err = mxuport_set_mcr(port, mcr_state);
733 	if (!err)
734 		mxport->mcr_state = mcr_state;
735 
736 	mutex_unlock(&mxport->mutex);
737 
738 	return err;
739 }
740 
741 static int mxuport_tiocmget(struct tty_struct *tty)
742 {
743 	struct mxuport_port *mxport;
744 	struct usb_serial_port *port = tty->driver_data;
745 	unsigned int result;
746 	unsigned long flags;
747 	unsigned int msr;
748 	unsigned int mcr;
749 
750 	mxport = usb_get_serial_port_data(port);
751 
752 	mutex_lock(&mxport->mutex);
753 	spin_lock_irqsave(&mxport->spinlock, flags);
754 
755 	msr = mxport->msr_state;
756 	mcr = mxport->mcr_state;
757 
758 	spin_unlock_irqrestore(&mxport->spinlock, flags);
759 	mutex_unlock(&mxport->mutex);
760 
761 	result = (((mcr & UART_MCR_DTR) ? TIOCM_DTR : 0) |	/* 0x002 */
762 		  ((mcr & UART_MCR_RTS) ? TIOCM_RTS : 0) |	/* 0x004 */
763 		  ((msr & UART_MSR_CTS) ? TIOCM_CTS : 0) |	/* 0x020 */
764 		  ((msr & UART_MSR_DCD) ? TIOCM_CAR : 0) |	/* 0x040 */
765 		  ((msr & UART_MSR_RI) ? TIOCM_RI : 0) |	/* 0x080 */
766 		  ((msr & UART_MSR_DSR) ? TIOCM_DSR : 0));	/* 0x100 */
767 
768 	dev_dbg(&port->dev, "%s - 0x%04x\n", __func__, result);
769 
770 	return result;
771 }
772 
773 static int mxuport_set_termios_flow(struct tty_struct *tty,
774 				    struct ktermios *old_termios,
775 				    struct usb_serial_port *port,
776 				    struct usb_serial *serial)
777 {
778 	u8 xon = START_CHAR(tty);
779 	u8 xoff = STOP_CHAR(tty);
780 	int enable;
781 	int err;
782 	u8 *buf;
783 	u8 rts;
784 
785 	buf = kmalloc(2, GFP_KERNEL);
786 	if (!buf)
787 		return -ENOMEM;
788 
789 	/* S/W flow control settings */
790 	if (I_IXOFF(tty) || I_IXON(tty)) {
791 		enable = 1;
792 		buf[0] = xon;
793 		buf[1] = xoff;
794 
795 		err = mxuport_send_ctrl_data_urb(serial, RQ_VENDOR_SET_CHARS,
796 						 0, port->port_number,
797 						 buf, 2);
798 		if (err)
799 			goto out;
800 
801 		dev_dbg(&port->dev, "%s - XON = 0x%02x, XOFF = 0x%02x\n",
802 			__func__, xon, xoff);
803 	} else {
804 		enable = 0;
805 	}
806 
807 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_XONXOFF,
808 				    enable, port->port_number);
809 	if (err)
810 		goto out;
811 
812 	rts = MX_RTS_NO_CHANGE;
813 
814 	/* H/W flow control settings */
815 	if (!old_termios ||
816 	    C_CRTSCTS(tty) != (old_termios->c_cflag & CRTSCTS)) {
817 		if (C_CRTSCTS(tty))
818 			rts = MX_RTS_HW;
819 		else
820 			rts = MX_RTS_ENABLE;
821 	}
822 
823 	if (C_BAUD(tty)) {
824 		if (old_termios && (old_termios->c_cflag & CBAUD) == B0) {
825 			/* Raise DTR and RTS */
826 			if (C_CRTSCTS(tty))
827 				rts = MX_RTS_HW;
828 			else
829 				rts = MX_RTS_ENABLE;
830 			mxuport_set_dtr(port, 1);
831 		}
832 	} else {
833 		/* Drop DTR and RTS */
834 		rts = MX_RTS_DISABLE;
835 		mxuport_set_dtr(port, 0);
836 	}
837 
838 	if (rts != MX_RTS_NO_CHANGE)
839 		err = mxuport_set_rts(port, rts);
840 
841 out:
842 	kfree(buf);
843 	return err;
844 }
845 
846 static void mxuport_set_termios(struct tty_struct *tty,
847 				struct usb_serial_port *port,
848 				struct ktermios *old_termios)
849 {
850 	struct usb_serial *serial = port->serial;
851 	u8 *buf;
852 	u8 data_bits;
853 	u8 stop_bits;
854 	u8 parity;
855 	int baud;
856 	int err;
857 
858 	if (old_termios &&
859 	    !tty_termios_hw_change(&tty->termios, old_termios) &&
860 	    tty->termios.c_iflag == old_termios->c_iflag) {
861 		dev_dbg(&port->dev, "%s - nothing to change\n", __func__);
862 		return;
863 	}
864 
865 	buf = kmalloc(4, GFP_KERNEL);
866 	if (!buf)
867 		return;
868 
869 	/* Set data bit of termios */
870 	switch (C_CSIZE(tty)) {
871 	case CS5:
872 		data_bits = MX_WORDLENGTH_5;
873 		break;
874 	case CS6:
875 		data_bits = MX_WORDLENGTH_6;
876 		break;
877 	case CS7:
878 		data_bits = MX_WORDLENGTH_7;
879 		break;
880 	case CS8:
881 	default:
882 		data_bits = MX_WORDLENGTH_8;
883 		break;
884 	}
885 
886 	/* Set parity of termios */
887 	if (C_PARENB(tty)) {
888 		if (C_CMSPAR(tty)) {
889 			if (C_PARODD(tty))
890 				parity = MX_PARITY_MARK;
891 			else
892 				parity = MX_PARITY_SPACE;
893 		} else {
894 			if (C_PARODD(tty))
895 				parity = MX_PARITY_ODD;
896 			else
897 				parity = MX_PARITY_EVEN;
898 		}
899 	} else {
900 		parity = MX_PARITY_NONE;
901 	}
902 
903 	/* Set stop bit of termios */
904 	if (C_CSTOPB(tty))
905 		stop_bits = MX_STOP_BITS_2;
906 	else
907 		stop_bits = MX_STOP_BITS_1;
908 
909 	buf[0] = data_bits;
910 	buf[1] = parity;
911 	buf[2] = stop_bits;
912 	buf[3] = 0;
913 
914 	err = mxuport_send_ctrl_data_urb(serial, RQ_VENDOR_SET_LINE,
915 					 0, port->port_number, buf, 4);
916 	if (err)
917 		goto out;
918 
919 	err = mxuport_set_termios_flow(tty, old_termios, port, serial);
920 	if (err)
921 		goto out;
922 
923 	baud = tty_get_baud_rate(tty);
924 	if (!baud)
925 		baud = 9600;
926 
927 	/* Note: Little Endian */
928 	put_unaligned_le32(baud, buf);
929 
930 	err = mxuport_send_ctrl_data_urb(serial, RQ_VENDOR_SET_BAUD,
931 					 0, port->port_number,
932 					 buf, 4);
933 	if (err)
934 		goto out;
935 
936 	dev_dbg(&port->dev, "baud_rate	: %d\n", baud);
937 	dev_dbg(&port->dev, "data_bits	: %d\n", data_bits);
938 	dev_dbg(&port->dev, "parity	: %d\n", parity);
939 	dev_dbg(&port->dev, "stop_bits	: %d\n", stop_bits);
940 
941 out:
942 	kfree(buf);
943 }
944 
945 /*
946  * Determine how many ports this device has dynamically.  It will be
947  * called after the probe() callback is called, but before attach().
948  */
949 static int mxuport_calc_num_ports(struct usb_serial *serial)
950 {
951 	unsigned long features = (unsigned long)usb_get_serial_data(serial);
952 
953 	if (features & MX_UPORT_2_PORT)
954 		return 2;
955 	if (features & MX_UPORT_4_PORT)
956 		return 4;
957 	if (features & MX_UPORT_8_PORT)
958 		return 8;
959 	if (features & MX_UPORT_16_PORT)
960 		return 16;
961 
962 	return 0;
963 }
964 
965 /* Get the version of the firmware currently running. */
966 static int mxuport_get_fw_version(struct usb_serial *serial, u32 *version)
967 {
968 	u8 *ver_buf;
969 	int err;
970 
971 	ver_buf = kzalloc(4, GFP_KERNEL);
972 	if (!ver_buf)
973 		return -ENOMEM;
974 
975 	/* Get firmware version from SDRAM */
976 	err = mxuport_recv_ctrl_urb(serial, RQ_VENDOR_GET_VERSION, 0, 0,
977 				    ver_buf, 4);
978 	if (err != 4) {
979 		err = -EIO;
980 		goto out;
981 	}
982 
983 	*version = (ver_buf[0] << 16) | (ver_buf[1] << 8) | ver_buf[2];
984 	err = 0;
985 out:
986 	kfree(ver_buf);
987 	return err;
988 }
989 
990 /* Given a firmware blob, download it to the device. */
991 static int mxuport_download_fw(struct usb_serial *serial,
992 			       const struct firmware *fw_p)
993 {
994 	u8 *fw_buf;
995 	size_t txlen;
996 	size_t fwidx;
997 	int err;
998 
999 	fw_buf = kmalloc(DOWN_BLOCK_SIZE, GFP_KERNEL);
1000 	if (!fw_buf)
1001 		return -ENOMEM;
1002 
1003 	dev_dbg(&serial->interface->dev, "Starting firmware download...\n");
1004 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_START_FW_DOWN, 0, 0);
1005 	if (err)
1006 		goto out;
1007 
1008 	fwidx = 0;
1009 	do {
1010 		txlen = min_t(size_t, (fw_p->size - fwidx), DOWN_BLOCK_SIZE);
1011 
1012 		memcpy(fw_buf, &fw_p->data[fwidx], txlen);
1013 		err = mxuport_send_ctrl_data_urb(serial, RQ_VENDOR_FW_DATA,
1014 						 0, 0, fw_buf, txlen);
1015 		if (err) {
1016 			mxuport_send_ctrl_urb(serial, RQ_VENDOR_STOP_FW_DOWN,
1017 					      0, 0);
1018 			goto out;
1019 		}
1020 
1021 		fwidx += txlen;
1022 		usleep_range(1000, 2000);
1023 
1024 	} while (fwidx < fw_p->size);
1025 
1026 	msleep(1000);
1027 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_STOP_FW_DOWN, 0, 0);
1028 	if (err)
1029 		goto out;
1030 
1031 	msleep(1000);
1032 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_QUERY_FW_READY, 0, 0);
1033 
1034 out:
1035 	kfree(fw_buf);
1036 	return err;
1037 }
1038 
1039 static int mxuport_probe(struct usb_serial *serial,
1040 			 const struct usb_device_id *id)
1041 {
1042 	u16 productid = le16_to_cpu(serial->dev->descriptor.idProduct);
1043 	const struct firmware *fw_p = NULL;
1044 	u32 version;
1045 	int local_ver;
1046 	char buf[32];
1047 	int err;
1048 
1049 	/* Load our firmware */
1050 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_QUERY_FW_CONFIG, 0, 0);
1051 	if (err) {
1052 		mxuport_send_ctrl_urb(serial, RQ_VENDOR_RESET_DEVICE, 0, 0);
1053 		return err;
1054 	}
1055 
1056 	err = mxuport_get_fw_version(serial, &version);
1057 	if (err < 0)
1058 		return err;
1059 
1060 	dev_dbg(&serial->interface->dev, "Device firmware version v%x.%x.%x\n",
1061 		(version & 0xff0000) >> 16,
1062 		(version & 0xff00) >> 8,
1063 		(version & 0xff));
1064 
1065 	snprintf(buf, sizeof(buf) - 1, "moxa/moxa-%04x.fw", productid);
1066 
1067 	err = request_firmware(&fw_p, buf, &serial->interface->dev);
1068 	if (err) {
1069 		dev_warn(&serial->interface->dev, "Firmware %s not found\n",
1070 			 buf);
1071 
1072 		/* Use the firmware already in the device */
1073 		err = 0;
1074 	} else {
1075 		local_ver = ((fw_p->data[VER_ADDR_1] << 16) |
1076 			     (fw_p->data[VER_ADDR_2] << 8) |
1077 			     fw_p->data[VER_ADDR_3]);
1078 		dev_dbg(&serial->interface->dev,
1079 			"Available firmware version v%x.%x.%x\n",
1080 			fw_p->data[VER_ADDR_1], fw_p->data[VER_ADDR_2],
1081 			fw_p->data[VER_ADDR_3]);
1082 		if (local_ver > version) {
1083 			err = mxuport_download_fw(serial, fw_p);
1084 			if (err)
1085 				goto out;
1086 			err  = mxuport_get_fw_version(serial, &version);
1087 			if (err < 0)
1088 				goto out;
1089 		}
1090 	}
1091 
1092 	dev_info(&serial->interface->dev,
1093 		 "Using device firmware version v%x.%x.%x\n",
1094 		 (version & 0xff0000) >> 16,
1095 		 (version & 0xff00) >> 8,
1096 		 (version & 0xff));
1097 
1098 	/*
1099 	 * Contains the features of this hardware. Store away for
1100 	 * later use, eg, number of ports.
1101 	 */
1102 	usb_set_serial_data(serial, (void *)id->driver_info);
1103 out:
1104 	if (fw_p)
1105 		release_firmware(fw_p);
1106 	return err;
1107 }
1108 
1109 
1110 static int mxuport_port_probe(struct usb_serial_port *port)
1111 {
1112 	struct usb_serial *serial = port->serial;
1113 	struct mxuport_port *mxport;
1114 	int err;
1115 
1116 	mxport = devm_kzalloc(&port->dev, sizeof(struct mxuport_port),
1117 			      GFP_KERNEL);
1118 	if (!mxport)
1119 		return -ENOMEM;
1120 
1121 	mutex_init(&mxport->mutex);
1122 	spin_lock_init(&mxport->spinlock);
1123 
1124 	/* Set the port private data */
1125 	usb_set_serial_port_data(port, mxport);
1126 
1127 	/* Set FIFO (Enable) */
1128 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_FIFO_DISABLE,
1129 				    0, port->port_number);
1130 	if (err)
1131 		return err;
1132 
1133 	/* Set transmission mode (Hi-Performance) */
1134 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_HIGH_PERFOR,
1135 				    0, port->port_number);
1136 	if (err)
1137 		return err;
1138 
1139 	/* Set interface (RS-232) */
1140 	return mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_INTERFACE,
1141 				     MX_INT_RS232,
1142 				     port->port_number);
1143 }
1144 
1145 static int mxuport_alloc_write_urb(struct usb_serial *serial,
1146 				   struct usb_serial_port *port,
1147 				   struct usb_serial_port *port0,
1148 				   int j)
1149 {
1150 	struct usb_device *dev = interface_to_usbdev(serial->interface);
1151 
1152 	set_bit(j, &port->write_urbs_free);
1153 	port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
1154 	if (!port->write_urbs[j])
1155 		return -ENOMEM;
1156 
1157 	port->bulk_out_buffers[j] = kmalloc(port0->bulk_out_size, GFP_KERNEL);
1158 	if (!port->bulk_out_buffers[j])
1159 		return -ENOMEM;
1160 
1161 	usb_fill_bulk_urb(port->write_urbs[j], dev,
1162 			  usb_sndbulkpipe(dev, port->bulk_out_endpointAddress),
1163 			  port->bulk_out_buffers[j],
1164 			  port->bulk_out_size,
1165 			  serial->type->write_bulk_callback,
1166 			  port);
1167 	return 0;
1168 }
1169 
1170 
1171 static int mxuport_alloc_write_urbs(struct usb_serial *serial,
1172 				    struct usb_serial_port *port,
1173 				    struct usb_serial_port *port0)
1174 {
1175 	int j;
1176 	int ret;
1177 
1178 	for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
1179 		ret = mxuport_alloc_write_urb(serial, port, port0, j);
1180 		if (ret)
1181 			return ret;
1182 	}
1183 	return 0;
1184 }
1185 
1186 
1187 static int mxuport_attach(struct usb_serial *serial)
1188 {
1189 	struct usb_serial_port *port0 = serial->port[0];
1190 	struct usb_serial_port *port1 = serial->port[1];
1191 	struct usb_serial_port *port;
1192 	int err;
1193 	int i;
1194 	int j;
1195 
1196 	/*
1197 	 * Throw away all but the first allocated write URBs so we can
1198 	 * set them up again to fit the multiplexing scheme.
1199 	 */
1200 	for (i = 1; i < serial->num_bulk_out; ++i) {
1201 		port = serial->port[i];
1202 		for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
1203 			usb_free_urb(port->write_urbs[j]);
1204 			kfree(port->bulk_out_buffers[j]);
1205 			port->write_urbs[j] = NULL;
1206 			port->bulk_out_buffers[j] = NULL;
1207 		}
1208 		port->write_urbs_free = 0;
1209 	}
1210 
1211 	/*
1212 	 * All write data is sent over the first bulk out endpoint,
1213 	 * with an added header to indicate the port. Allocate URBs
1214 	 * for each port to the first bulk out endpoint.
1215 	 */
1216 	for (i = 1; i < serial->num_ports; ++i) {
1217 		port = serial->port[i];
1218 		port->bulk_out_size = port0->bulk_out_size;
1219 		port->bulk_out_endpointAddress =
1220 			port0->bulk_out_endpointAddress;
1221 
1222 		err = mxuport_alloc_write_urbs(serial, port, port0);
1223 		if (err)
1224 			return err;
1225 
1226 		port->write_urb = port->write_urbs[0];
1227 		port->bulk_out_buffer = port->bulk_out_buffers[0];
1228 
1229 		/*
1230 		 * Ensure each port has a fifo. The framework only
1231 		 * allocates a fifo to ports with a bulk out endpoint,
1232 		 * where as we need one for every port.
1233 		 */
1234 		if (!kfifo_initialized(&port->write_fifo)) {
1235 			err = kfifo_alloc(&port->write_fifo, PAGE_SIZE,
1236 					  GFP_KERNEL);
1237 			if (err)
1238 				return err;
1239 		}
1240 	}
1241 
1242 	/*
1243 	 * All data from the ports is received on the first bulk in
1244 	 * endpoint, with a multiplex header. The second bulk in is
1245 	 * used for events.
1246 	 *
1247 	 * Start to read from the device.
1248 	 */
1249 	err = usb_serial_generic_submit_read_urbs(port0, GFP_KERNEL);
1250 	if (err)
1251 		return err;
1252 
1253 	err = usb_serial_generic_submit_read_urbs(port1, GFP_KERNEL);
1254 	if (err) {
1255 		usb_serial_generic_close(port0);
1256 		return err;
1257 	}
1258 
1259 	return 0;
1260 }
1261 
1262 static int mxuport_open(struct tty_struct *tty, struct usb_serial_port *port)
1263 {
1264 	struct mxuport_port *mxport = usb_get_serial_port_data(port);
1265 	struct usb_serial *serial = port->serial;
1266 	int err;
1267 
1268 	/* Set receive host (enable) */
1269 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_RX_HOST_EN,
1270 				    1, port->port_number);
1271 	if (err)
1272 		return err;
1273 
1274 	err = mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_OPEN,
1275 				    1, port->port_number);
1276 	if (err) {
1277 		mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_RX_HOST_EN,
1278 				      0, port->port_number);
1279 		return err;
1280 	}
1281 
1282 	/* Initial port termios */
1283 	if (tty)
1284 		mxuport_set_termios(tty, port, NULL);
1285 
1286 	/*
1287 	 * TODO: use RQ_VENDOR_GET_MSR, once we know what it
1288 	 * returns.
1289 	 */
1290 	mxport->msr_state = 0;
1291 
1292 	return err;
1293 }
1294 
1295 static void mxuport_close(struct usb_serial_port *port)
1296 {
1297 	struct usb_serial *serial = port->serial;
1298 
1299 	mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_OPEN, 0,
1300 			      port->port_number);
1301 
1302 	mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_RX_HOST_EN, 0,
1303 			      port->port_number);
1304 }
1305 
1306 /* Send a break to the port. */
1307 static void mxuport_break_ctl(struct tty_struct *tty, int break_state)
1308 {
1309 	struct usb_serial_port *port = tty->driver_data;
1310 	struct usb_serial *serial = port->serial;
1311 	int enable;
1312 
1313 	if (break_state == -1) {
1314 		enable = 1;
1315 		dev_dbg(&port->dev, "%s - sending break\n", __func__);
1316 	} else {
1317 		enable = 0;
1318 		dev_dbg(&port->dev, "%s - clearing break\n", __func__);
1319 	}
1320 
1321 	mxuport_send_ctrl_urb(serial, RQ_VENDOR_SET_BREAK,
1322 			      enable, port->port_number);
1323 }
1324 
1325 static int mxuport_resume(struct usb_serial *serial)
1326 {
1327 	struct usb_serial_port *port;
1328 	int c = 0;
1329 	int i;
1330 	int r;
1331 
1332 	for (i = 0; i < 2; i++) {
1333 		port = serial->port[i];
1334 
1335 		r = usb_serial_generic_submit_read_urbs(port, GFP_NOIO);
1336 		if (r < 0)
1337 			c++;
1338 	}
1339 
1340 	for (i = 0; i < serial->num_ports; i++) {
1341 		port = serial->port[i];
1342 		if (!test_bit(ASYNCB_INITIALIZED, &port->port.flags))
1343 			continue;
1344 
1345 		r = usb_serial_generic_write_start(port, GFP_NOIO);
1346 		if (r < 0)
1347 			c++;
1348 	}
1349 
1350 	return c ? -EIO : 0;
1351 }
1352 
1353 static struct usb_serial_driver mxuport_device = {
1354 	.driver = {
1355 		.owner =	THIS_MODULE,
1356 		.name =		"mxuport",
1357 	},
1358 	.description		= "MOXA UPort",
1359 	.id_table		= mxuport_idtable,
1360 	.num_ports		= 0,
1361 	.probe			= mxuport_probe,
1362 	.port_probe		= mxuport_port_probe,
1363 	.attach			= mxuport_attach,
1364 	.calc_num_ports		= mxuport_calc_num_ports,
1365 	.open			= mxuport_open,
1366 	.close			= mxuport_close,
1367 	.set_termios		= mxuport_set_termios,
1368 	.break_ctl		= mxuport_break_ctl,
1369 	.tx_empty		= mxuport_tx_empty,
1370 	.tiocmiwait		= usb_serial_generic_tiocmiwait,
1371 	.get_icount		= usb_serial_generic_get_icount,
1372 	.throttle		= mxuport_throttle,
1373 	.unthrottle		= mxuport_unthrottle,
1374 	.tiocmget		= mxuport_tiocmget,
1375 	.tiocmset		= mxuport_tiocmset,
1376 	.dtr_rts		= mxuport_dtr_rts,
1377 	.process_read_urb	= mxuport_process_read_urb,
1378 	.prepare_write_buffer	= mxuport_prepare_write_buffer,
1379 	.resume			= mxuport_resume,
1380 };
1381 
1382 static struct usb_serial_driver *const serial_drivers[] = {
1383 	&mxuport_device, NULL
1384 };
1385 
1386 module_usb_serial_driver(serial_drivers, mxuport_idtable);
1387 
1388 MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
1389 MODULE_AUTHOR("<support@moxa.com>");
1390 MODULE_LICENSE("GPL");
1391