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v5.9
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * USB Cypress M8 driver
   4 *
   5 * 	Copyright (C) 2004
   6 * 	    Lonnie Mendez (dignome@gmail.com)
   7 *	Copyright (C) 2003,2004
   8 *	    Neil Whelchel (koyama@firstlight.net)
   9 *
  10 * See Documentation/usb/usb-serial.rst for more information on using this
  11 * driver
  12 *
  13 * See http://geocities.com/i0xox0i for information on this driver and the
  14 * earthmate usb device.
  15 */
  16
  17/* Thanks to Neil Whelchel for writing the first cypress m8 implementation
  18   for linux. */
  19/* Thanks to cypress for providing references for the hid reports. */
  20/* Thanks to Jiang Zhang for providing links and for general help. */
  21/* Code originates and was built up from ftdi_sio, belkin, pl2303 and others.*/
  22
  23
  24#include <linux/kernel.h>
  25#include <linux/errno.h>
  26#include <linux/slab.h>
  27#include <linux/tty.h>
  28#include <linux/tty_driver.h>
  29#include <linux/tty_flip.h>
  30#include <linux/module.h>
  31#include <linux/moduleparam.h>
  32#include <linux/spinlock.h>
  33#include <linux/usb.h>
  34#include <linux/usb/serial.h>
  35#include <linux/serial.h>
  36#include <linux/kfifo.h>
  37#include <linux/delay.h>
  38#include <linux/uaccess.h>
  39#include <asm/unaligned.h>
  40
  41#include "cypress_m8.h"
  42
  43
  44static bool stats;
  45static int interval;
  46static bool unstable_bauds;
  47
  48#define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
  49#define DRIVER_DESC "Cypress USB to Serial Driver"
  50
  51/* write buffer size defines */
  52#define CYPRESS_BUF_SIZE	1024
  53
  54static const struct usb_device_id id_table_earthmate[] = {
  55	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  56	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  57	{ }						/* Terminating entry */
  58};
  59
  60static const struct usb_device_id id_table_cyphidcomrs232[] = {
  61	{ USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  62	{ USB_DEVICE(VENDOR_ID_SAI, PRODUCT_ID_CYPHIDCOM) },
  63	{ USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  64	{ USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
  65	{ }						/* Terminating entry */
  66};
  67
  68static const struct usb_device_id id_table_nokiaca42v2[] = {
  69	{ USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
  70	{ }						/* Terminating entry */
  71};
  72
  73static const struct usb_device_id id_table_combined[] = {
  74	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  75	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  76	{ USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  77	{ USB_DEVICE(VENDOR_ID_SAI, PRODUCT_ID_CYPHIDCOM) },
  78	{ USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  79	{ USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
  80	{ USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
  81	{ }						/* Terminating entry */
  82};
  83
  84MODULE_DEVICE_TABLE(usb, id_table_combined);
  85
  86enum packet_format {
  87	packet_format_1,  /* b0:status, b1:payload count */
  88	packet_format_2   /* b0[7:3]:status, b0[2:0]:payload count */
  89};
  90
  91struct cypress_private {
  92	spinlock_t lock;		   /* private lock */
  93	int chiptype;			   /* identifier of device, for quirks/etc */
  94	int bytes_in;			   /* used for statistics */
  95	int bytes_out;			   /* used for statistics */
  96	int cmd_count;			   /* used for statistics */
  97	int cmd_ctrl;			   /* always set this to 1 before issuing a command */
  98	struct kfifo write_fifo;	   /* write fifo */
  99	int write_urb_in_use;		   /* write urb in use indicator */
 100	int write_urb_interval;            /* interval to use for write urb */
 101	int read_urb_interval;             /* interval to use for read urb */
 102	int comm_is_ok;                    /* true if communication is (still) ok */
 103	__u8 line_control;	   	   /* holds dtr / rts value */
 104	__u8 current_status;	   	   /* received from last read - info on dsr,cts,cd,ri,etc */
 105	__u8 current_config;	   	   /* stores the current configuration byte */
 106	__u8 rx_flags;			   /* throttling - used from whiteheat/ftdi_sio */
 107	enum packet_format pkt_fmt;	   /* format to use for packet send / receive */
 108	int get_cfg_unsafe;		   /* If true, the CYPRESS_GET_CONFIG is unsafe */
 109	int baud_rate;			   /* stores current baud rate in
 110					      integer form */
 111	char prev_status;		   /* used for TIOCMIWAIT */
 112};
 113
 114/* function prototypes for the Cypress USB to serial device */
 115static int  cypress_earthmate_port_probe(struct usb_serial_port *port);
 116static int  cypress_hidcom_port_probe(struct usb_serial_port *port);
 117static int  cypress_ca42v2_port_probe(struct usb_serial_port *port);
 118static int  cypress_port_remove(struct usb_serial_port *port);
 119static int  cypress_open(struct tty_struct *tty, struct usb_serial_port *port);
 120static void cypress_close(struct usb_serial_port *port);
 121static void cypress_dtr_rts(struct usb_serial_port *port, int on);
 122static int  cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 123			const unsigned char *buf, int count);
 124static void cypress_send(struct usb_serial_port *port);
 125static int  cypress_write_room(struct tty_struct *tty);
 126static void cypress_earthmate_init_termios(struct tty_struct *tty);
 127static void cypress_set_termios(struct tty_struct *tty,
 128			struct usb_serial_port *port, struct ktermios *old);
 129static int  cypress_tiocmget(struct tty_struct *tty);
 130static int  cypress_tiocmset(struct tty_struct *tty,
 131			unsigned int set, unsigned int clear);
 132static int  cypress_chars_in_buffer(struct tty_struct *tty);
 133static void cypress_throttle(struct tty_struct *tty);
 134static void cypress_unthrottle(struct tty_struct *tty);
 135static void cypress_set_dead(struct usb_serial_port *port);
 136static void cypress_read_int_callback(struct urb *urb);
 137static void cypress_write_int_callback(struct urb *urb);
 138
 139static struct usb_serial_driver cypress_earthmate_device = {
 140	.driver = {
 141		.owner =		THIS_MODULE,
 142		.name =			"earthmate",
 143	},
 144	.description =			"DeLorme Earthmate USB",
 145	.id_table =			id_table_earthmate,
 146	.num_ports =			1,
 147	.port_probe =			cypress_earthmate_port_probe,
 148	.port_remove =			cypress_port_remove,
 149	.open =				cypress_open,
 150	.close =			cypress_close,
 151	.dtr_rts =			cypress_dtr_rts,
 152	.write =			cypress_write,
 153	.write_room =			cypress_write_room,
 154	.init_termios =			cypress_earthmate_init_termios,
 155	.set_termios =			cypress_set_termios,
 156	.tiocmget =			cypress_tiocmget,
 157	.tiocmset =			cypress_tiocmset,
 158	.tiocmiwait =			usb_serial_generic_tiocmiwait,
 159	.chars_in_buffer =		cypress_chars_in_buffer,
 160	.throttle =		 	cypress_throttle,
 161	.unthrottle =			cypress_unthrottle,
 162	.read_int_callback =		cypress_read_int_callback,
 163	.write_int_callback =		cypress_write_int_callback,
 164};
 165
 166static struct usb_serial_driver cypress_hidcom_device = {
 167	.driver = {
 168		.owner =		THIS_MODULE,
 169		.name =			"cyphidcom",
 170	},
 171	.description =			"HID->COM RS232 Adapter",
 172	.id_table =			id_table_cyphidcomrs232,
 173	.num_ports =			1,
 174	.port_probe =			cypress_hidcom_port_probe,
 175	.port_remove =			cypress_port_remove,
 176	.open =				cypress_open,
 177	.close =			cypress_close,
 178	.dtr_rts =			cypress_dtr_rts,
 179	.write =			cypress_write,
 180	.write_room =			cypress_write_room,
 181	.set_termios =			cypress_set_termios,
 182	.tiocmget =			cypress_tiocmget,
 183	.tiocmset =			cypress_tiocmset,
 184	.tiocmiwait =			usb_serial_generic_tiocmiwait,
 185	.chars_in_buffer =		cypress_chars_in_buffer,
 186	.throttle =			cypress_throttle,
 187	.unthrottle =			cypress_unthrottle,
 188	.read_int_callback =		cypress_read_int_callback,
 189	.write_int_callback =		cypress_write_int_callback,
 190};
 191
 192static struct usb_serial_driver cypress_ca42v2_device = {
 193	.driver = {
 194		.owner =		THIS_MODULE,
 195		.name =			"nokiaca42v2",
 196	},
 197	.description =			"Nokia CA-42 V2 Adapter",
 198	.id_table =			id_table_nokiaca42v2,
 199	.num_ports =			1,
 200	.port_probe =			cypress_ca42v2_port_probe,
 201	.port_remove =			cypress_port_remove,
 202	.open =				cypress_open,
 203	.close =			cypress_close,
 204	.dtr_rts =			cypress_dtr_rts,
 205	.write =			cypress_write,
 206	.write_room =			cypress_write_room,
 207	.set_termios =			cypress_set_termios,
 208	.tiocmget =			cypress_tiocmget,
 209	.tiocmset =			cypress_tiocmset,
 210	.tiocmiwait =			usb_serial_generic_tiocmiwait,
 211	.chars_in_buffer =		cypress_chars_in_buffer,
 212	.throttle =			cypress_throttle,
 213	.unthrottle =			cypress_unthrottle,
 214	.read_int_callback =		cypress_read_int_callback,
 215	.write_int_callback =		cypress_write_int_callback,
 216};
 217
 218static struct usb_serial_driver * const serial_drivers[] = {
 219	&cypress_earthmate_device, &cypress_hidcom_device,
 220	&cypress_ca42v2_device, NULL
 221};
 222
 223/*****************************************************************************
 224 * Cypress serial helper functions
 225 *****************************************************************************/
 226
 227/* FRWD Dongle hidcom needs to skip reset and speed checks */
 228static inline bool is_frwd(struct usb_device *dev)
 229{
 230	return ((le16_to_cpu(dev->descriptor.idVendor) == VENDOR_ID_FRWD) &&
 231		(le16_to_cpu(dev->descriptor.idProduct) == PRODUCT_ID_CYPHIDCOM_FRWD));
 232}
 233
 234static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
 235{
 236	struct cypress_private *priv;
 237	priv = usb_get_serial_port_data(port);
 238
 239	if (unstable_bauds)
 240		return new_rate;
 241
 242	/* FRWD Dongle uses 115200 bps */
 243	if (is_frwd(port->serial->dev))
 244		return new_rate;
 245
 246	/*
 247	 * The general purpose firmware for the Cypress M8 allows for
 248	 * a maximum speed of 57600bps (I have no idea whether DeLorme
 249	 * chose to use the general purpose firmware or not), if you
 250	 * need to modify this speed setting for your own project
 251	 * please add your own chiptype and modify the code likewise.
 252	 * The Cypress HID->COM device will work successfully up to
 253	 * 115200bps (but the actual throughput is around 3kBps).
 254	 */
 255	if (port->serial->dev->speed == USB_SPEED_LOW) {
 256		/*
 257		 * Mike Isely <isely@pobox.com> 2-Feb-2008: The
 258		 * Cypress app note that describes this mechanism
 259		 * states the the low-speed part can't handle more
 260		 * than 800 bytes/sec, in which case 4800 baud is the
 261		 * safest speed for a part like that.
 262		 */
 263		if (new_rate > 4800) {
 264			dev_dbg(&port->dev,
 265				"%s - failed setting baud rate, device incapable speed %d\n",
 266				__func__, new_rate);
 267			return -1;
 268		}
 269	}
 270	switch (priv->chiptype) {
 271	case CT_EARTHMATE:
 272		if (new_rate <= 600) {
 273			/* 300 and 600 baud rates are supported under
 274			 * the generic firmware, but are not used with
 275			 * NMEA and SiRF protocols */
 276			dev_dbg(&port->dev,
 277				"%s - failed setting baud rate, unsupported speed of %d on Earthmate GPS\n",
 278				__func__, new_rate);
 279			return -1;
 280		}
 281		break;
 282	default:
 283		break;
 284	}
 285	return new_rate;
 286}
 287
 288
 289/* This function can either set or retrieve the current serial line settings */
 290static int cypress_serial_control(struct tty_struct *tty,
 291	struct usb_serial_port *port, speed_t baud_rate, int data_bits,
 292	int stop_bits, int parity_enable, int parity_type, int reset,
 293	int cypress_request_type)
 294{
 295	int new_baudrate = 0, retval = 0, tries = 0;
 296	struct cypress_private *priv;
 297	struct device *dev = &port->dev;
 298	u8 *feature_buffer;
 299	const unsigned int feature_len = 5;
 300	unsigned long flags;
 301
 302	priv = usb_get_serial_port_data(port);
 303
 304	if (!priv->comm_is_ok)
 305		return -ENODEV;
 306
 307	feature_buffer = kcalloc(feature_len, sizeof(u8), GFP_KERNEL);
 308	if (!feature_buffer)
 309		return -ENOMEM;
 310
 311	switch (cypress_request_type) {
 312	case CYPRESS_SET_CONFIG:
 313		/* 0 means 'Hang up' so doesn't change the true bit rate */
 314		new_baudrate = priv->baud_rate;
 315		if (baud_rate && baud_rate != priv->baud_rate) {
 316			dev_dbg(dev, "%s - baud rate is changing\n", __func__);
 317			retval = analyze_baud_rate(port, baud_rate);
 318			if (retval >= 0) {
 319				new_baudrate = retval;
 320				dev_dbg(dev, "%s - New baud rate set to %d\n",
 321					__func__, new_baudrate);
 322			}
 323		}
 324		dev_dbg(dev, "%s - baud rate is being sent as %d\n", __func__,
 325			new_baudrate);
 326
 327		/* fill the feature_buffer with new configuration */
 328		put_unaligned_le32(new_baudrate, feature_buffer);
 329		feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
 330		/* 1 bit gap */
 331		feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
 332		feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
 333		feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
 334		/* 1 bit gap */
 335		feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
 336
 337		dev_dbg(dev, "%s - device is being sent this feature report:\n", __func__);
 338		dev_dbg(dev, "%s - %02X - %02X - %02X - %02X - %02X\n", __func__,
 339			feature_buffer[0], feature_buffer[1],
 340			feature_buffer[2], feature_buffer[3],
 341			feature_buffer[4]);
 342
 343		do {
 344			retval = usb_control_msg(port->serial->dev,
 345					usb_sndctrlpipe(port->serial->dev, 0),
 346					HID_REQ_SET_REPORT,
 347					USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 348					0x0300, 0, feature_buffer,
 349					feature_len, 500);
 350
 351			if (tries++ >= 3)
 352				break;
 353
 354		} while (retval != feature_len &&
 355			 retval != -ENODEV);
 356
 357		if (retval != feature_len) {
 358			dev_err(dev, "%s - failed sending serial line settings - %d\n",
 359				__func__, retval);
 360			cypress_set_dead(port);
 361		} else {
 362			spin_lock_irqsave(&priv->lock, flags);
 363			priv->baud_rate = new_baudrate;
 364			priv->current_config = feature_buffer[4];
 365			spin_unlock_irqrestore(&priv->lock, flags);
 366			/* If we asked for a speed change encode it */
 367			if (baud_rate)
 368				tty_encode_baud_rate(tty,
 369					new_baudrate, new_baudrate);
 370		}
 371	break;
 372	case CYPRESS_GET_CONFIG:
 373		if (priv->get_cfg_unsafe) {
 374			/* Not implemented for this device,
 375			   and if we try to do it we're likely
 376			   to crash the hardware. */
 377			retval = -ENOTTY;
 378			goto out;
 379		}
 380		dev_dbg(dev, "%s - retrieving serial line settings\n", __func__);
 381		do {
 382			retval = usb_control_msg(port->serial->dev,
 383					usb_rcvctrlpipe(port->serial->dev, 0),
 384					HID_REQ_GET_REPORT,
 385					USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 386					0x0300, 0, feature_buffer,
 387					feature_len, 500);
 388
 389			if (tries++ >= 3)
 390				break;
 391		} while (retval != feature_len
 392						&& retval != -ENODEV);
 393
 394		if (retval != feature_len) {
 395			dev_err(dev, "%s - failed to retrieve serial line settings - %d\n",
 396				__func__, retval);
 397			cypress_set_dead(port);
 398			goto out;
 399		} else {
 400			spin_lock_irqsave(&priv->lock, flags);
 401			/* store the config in one byte, and later
 402			   use bit masks to check values */
 403			priv->current_config = feature_buffer[4];
 404			priv->baud_rate = get_unaligned_le32(feature_buffer);
 405			spin_unlock_irqrestore(&priv->lock, flags);
 406		}
 407	}
 408	spin_lock_irqsave(&priv->lock, flags);
 409	++priv->cmd_count;
 410	spin_unlock_irqrestore(&priv->lock, flags);
 411out:
 412	kfree(feature_buffer);
 413	return retval;
 414} /* cypress_serial_control */
 415
 416
 417static void cypress_set_dead(struct usb_serial_port *port)
 418{
 419	struct cypress_private *priv = usb_get_serial_port_data(port);
 420	unsigned long flags;
 421
 422	spin_lock_irqsave(&priv->lock, flags);
 423	if (!priv->comm_is_ok) {
 424		spin_unlock_irqrestore(&priv->lock, flags);
 425		return;
 426	}
 427	priv->comm_is_ok = 0;
 428	spin_unlock_irqrestore(&priv->lock, flags);
 429
 430	dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
 431		"interval might be too short\n", port->port_number);
 432}
 433
 434
 435/*****************************************************************************
 436 * Cypress serial driver functions
 437 *****************************************************************************/
 438
 439
 440static int cypress_generic_port_probe(struct usb_serial_port *port)
 441{
 442	struct usb_serial *serial = port->serial;
 443	struct cypress_private *priv;
 444
 445	if (!port->interrupt_out_urb || !port->interrupt_in_urb) {
 446		dev_err(&port->dev, "required endpoint is missing\n");
 447		return -ENODEV;
 448	}
 449
 450	priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL);
 451	if (!priv)
 452		return -ENOMEM;
 453
 454	priv->comm_is_ok = !0;
 455	spin_lock_init(&priv->lock);
 456	if (kfifo_alloc(&priv->write_fifo, CYPRESS_BUF_SIZE, GFP_KERNEL)) {
 457		kfree(priv);
 458		return -ENOMEM;
 459	}
 460
 461	/* Skip reset for FRWD device. It is a workaound:
 462	   device hangs if it receives SET_CONFIGURE in Configured
 463	   state. */
 464	if (!is_frwd(serial->dev))
 465		usb_reset_configuration(serial->dev);
 466
 467	priv->cmd_ctrl = 0;
 468	priv->line_control = 0;
 469	priv->rx_flags = 0;
 470	/* Default packet format setting is determined by packet size.
 471	   Anything with a size larger then 9 must have a separate
 472	   count field since the 3 bit count field is otherwise too
 473	   small.  Otherwise we can use the slightly more compact
 474	   format.  This is in accordance with the cypress_m8 serial
 475	   converter app note. */
 476	if (port->interrupt_out_size > 9)
 477		priv->pkt_fmt = packet_format_1;
 478	else
 479		priv->pkt_fmt = packet_format_2;
 480
 481	if (interval > 0) {
 482		priv->write_urb_interval = interval;
 483		priv->read_urb_interval = interval;
 484		dev_dbg(&port->dev, "%s - read & write intervals forced to %d\n",
 485			__func__, interval);
 486	} else {
 487		priv->write_urb_interval = port->interrupt_out_urb->interval;
 488		priv->read_urb_interval = port->interrupt_in_urb->interval;
 489		dev_dbg(&port->dev, "%s - intervals: read=%d write=%d\n",
 490			__func__, priv->read_urb_interval,
 491			priv->write_urb_interval);
 492	}
 493	usb_set_serial_port_data(port, priv);
 494
 495	port->port.drain_delay = 256;
 496
 497	return 0;
 498}
 499
 500
 501static int cypress_earthmate_port_probe(struct usb_serial_port *port)
 502{
 503	struct usb_serial *serial = port->serial;
 504	struct cypress_private *priv;
 505	int ret;
 506
 507	ret = cypress_generic_port_probe(port);
 508	if (ret) {
 509		dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 510		return ret;
 511	}
 512
 513	priv = usb_get_serial_port_data(port);
 514	priv->chiptype = CT_EARTHMATE;
 515	/* All Earthmate devices use the separated-count packet
 516	   format!  Idiotic. */
 517	priv->pkt_fmt = packet_format_1;
 518	if (serial->dev->descriptor.idProduct !=
 519				cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
 520		/* The old original USB Earthmate seemed able to
 521		   handle GET_CONFIG requests; everything they've
 522		   produced since that time crashes if this command is
 523		   attempted :-( */
 524		dev_dbg(&port->dev,
 525			"%s - Marking this device as unsafe for GET_CONFIG commands\n",
 526			__func__);
 527		priv->get_cfg_unsafe = !0;
 528	}
 529
 530	return 0;
 531}
 532
 533static int cypress_hidcom_port_probe(struct usb_serial_port *port)
 534{
 535	struct cypress_private *priv;
 536	int ret;
 537
 538	ret = cypress_generic_port_probe(port);
 539	if (ret) {
 540		dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 541		return ret;
 542	}
 543
 544	priv = usb_get_serial_port_data(port);
 545	priv->chiptype = CT_CYPHIDCOM;
 546
 547	return 0;
 548}
 549
 550static int cypress_ca42v2_port_probe(struct usb_serial_port *port)
 551{
 552	struct cypress_private *priv;
 553	int ret;
 554
 555	ret = cypress_generic_port_probe(port);
 556	if (ret) {
 557		dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 558		return ret;
 559	}
 560
 561	priv = usb_get_serial_port_data(port);
 562	priv->chiptype = CT_CA42V2;
 563
 564	return 0;
 565}
 566
 567static int cypress_port_remove(struct usb_serial_port *port)
 568{
 569	struct cypress_private *priv;
 570
 571	priv = usb_get_serial_port_data(port);
 572
 573	kfifo_free(&priv->write_fifo);
 574	kfree(priv);
 575
 576	return 0;
 577}
 578
 579static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port)
 580{
 581	struct cypress_private *priv = usb_get_serial_port_data(port);
 582	struct usb_serial *serial = port->serial;
 583	unsigned long flags;
 584	int result = 0;
 585
 586	if (!priv->comm_is_ok)
 587		return -EIO;
 588
 589	/* clear halts before open */
 590	usb_clear_halt(serial->dev, 0x81);
 591	usb_clear_halt(serial->dev, 0x02);
 592
 593	spin_lock_irqsave(&priv->lock, flags);
 594	/* reset read/write statistics */
 595	priv->bytes_in = 0;
 596	priv->bytes_out = 0;
 597	priv->cmd_count = 0;
 598	priv->rx_flags = 0;
 599	spin_unlock_irqrestore(&priv->lock, flags);
 600
 601	/* Set termios */
 602	cypress_send(port);
 603
 604	if (tty)
 605		cypress_set_termios(tty, port, NULL);
 606
 607	/* setup the port and start reading from the device */
 608	usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 609		usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 610		port->interrupt_in_urb->transfer_buffer,
 611		port->interrupt_in_urb->transfer_buffer_length,
 612		cypress_read_int_callback, port, priv->read_urb_interval);
 613	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 614
 615	if (result) {
 616		dev_err(&port->dev,
 617			"%s - failed submitting read urb, error %d\n",
 618							__func__, result);
 619		cypress_set_dead(port);
 620	}
 621
 622	return result;
 623} /* cypress_open */
 624
 625static void cypress_dtr_rts(struct usb_serial_port *port, int on)
 626{
 627	struct cypress_private *priv = usb_get_serial_port_data(port);
 628	/* drop dtr and rts */
 629	spin_lock_irq(&priv->lock);
 630	if (on == 0)
 631		priv->line_control = 0;
 632	else 
 633		priv->line_control = CONTROL_DTR | CONTROL_RTS;
 634	priv->cmd_ctrl = 1;
 635	spin_unlock_irq(&priv->lock);
 636	cypress_write(NULL, port, NULL, 0);
 637}
 638
 639static void cypress_close(struct usb_serial_port *port)
 640{
 641	struct cypress_private *priv = usb_get_serial_port_data(port);
 642	unsigned long flags;
 643
 644	spin_lock_irqsave(&priv->lock, flags);
 645	kfifo_reset_out(&priv->write_fifo);
 646	spin_unlock_irqrestore(&priv->lock, flags);
 647
 648	dev_dbg(&port->dev, "%s - stopping urbs\n", __func__);
 649	usb_kill_urb(port->interrupt_in_urb);
 650	usb_kill_urb(port->interrupt_out_urb);
 651
 652	if (stats)
 653		dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
 654			priv->bytes_in, priv->bytes_out, priv->cmd_count);
 655} /* cypress_close */
 656
 657
 658static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 659					const unsigned char *buf, int count)
 660{
 661	struct cypress_private *priv = usb_get_serial_port_data(port);
 662
 663	dev_dbg(&port->dev, "%s - %d bytes\n", __func__, count);
 664
 665	/* line control commands, which need to be executed immediately,
 666	   are not put into the buffer for obvious reasons.
 667	 */
 668	if (priv->cmd_ctrl) {
 669		count = 0;
 670		goto finish;
 671	}
 672
 673	if (!count)
 674		return count;
 675
 676	count = kfifo_in_locked(&priv->write_fifo, buf, count, &priv->lock);
 677
 678finish:
 679	cypress_send(port);
 680
 681	return count;
 682} /* cypress_write */
 683
 684
 685static void cypress_send(struct usb_serial_port *port)
 686{
 687	int count = 0, result, offset, actual_size;
 688	struct cypress_private *priv = usb_get_serial_port_data(port);
 689	struct device *dev = &port->dev;
 690	unsigned long flags;
 691
 692	if (!priv->comm_is_ok)
 693		return;
 694
 695	dev_dbg(dev, "%s - interrupt out size is %d\n", __func__,
 696		port->interrupt_out_size);
 697
 698	spin_lock_irqsave(&priv->lock, flags);
 699	if (priv->write_urb_in_use) {
 700		dev_dbg(dev, "%s - can't write, urb in use\n", __func__);
 701		spin_unlock_irqrestore(&priv->lock, flags);
 702		return;
 703	}
 704	spin_unlock_irqrestore(&priv->lock, flags);
 705
 706	/* clear buffer */
 707	memset(port->interrupt_out_urb->transfer_buffer, 0,
 708						port->interrupt_out_size);
 709
 710	spin_lock_irqsave(&priv->lock, flags);
 711	switch (priv->pkt_fmt) {
 712	default:
 713	case packet_format_1:
 714		/* this is for the CY7C64013... */
 715		offset = 2;
 716		port->interrupt_out_buffer[0] = priv->line_control;
 717		break;
 718	case packet_format_2:
 719		/* this is for the CY7C63743... */
 720		offset = 1;
 721		port->interrupt_out_buffer[0] = priv->line_control;
 722		break;
 723	}
 724
 725	if (priv->line_control & CONTROL_RESET)
 726		priv->line_control &= ~CONTROL_RESET;
 727
 728	if (priv->cmd_ctrl) {
 729		priv->cmd_count++;
 730		dev_dbg(dev, "%s - line control command being issued\n", __func__);
 731		spin_unlock_irqrestore(&priv->lock, flags);
 732		goto send;
 733	} else
 734		spin_unlock_irqrestore(&priv->lock, flags);
 735
 736	count = kfifo_out_locked(&priv->write_fifo,
 737					&port->interrupt_out_buffer[offset],
 738					port->interrupt_out_size - offset,
 739					&priv->lock);
 740	if (count == 0)
 741		return;
 742
 743	switch (priv->pkt_fmt) {
 744	default:
 745	case packet_format_1:
 746		port->interrupt_out_buffer[1] = count;
 747		break;
 748	case packet_format_2:
 749		port->interrupt_out_buffer[0] |= count;
 750	}
 751
 752	dev_dbg(dev, "%s - count is %d\n", __func__, count);
 753
 754send:
 755	spin_lock_irqsave(&priv->lock, flags);
 756	priv->write_urb_in_use = 1;
 757	spin_unlock_irqrestore(&priv->lock, flags);
 758
 759	if (priv->cmd_ctrl)
 760		actual_size = 1;
 761	else
 762		actual_size = count +
 763			      (priv->pkt_fmt == packet_format_1 ? 2 : 1);
 764
 765	usb_serial_debug_data(dev, __func__, port->interrupt_out_size,
 766			      port->interrupt_out_urb->transfer_buffer);
 767
 768	usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
 769		usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
 770		port->interrupt_out_buffer, actual_size,
 771		cypress_write_int_callback, port, priv->write_urb_interval);
 772	result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
 773	if (result) {
 774		dev_err_console(port,
 775				"%s - failed submitting write urb, error %d\n",
 776							__func__, result);
 777		priv->write_urb_in_use = 0;
 778		cypress_set_dead(port);
 779	}
 780
 781	spin_lock_irqsave(&priv->lock, flags);
 782	if (priv->cmd_ctrl)
 783		priv->cmd_ctrl = 0;
 784
 785	/* do not count the line control and size bytes */
 786	priv->bytes_out += count;
 787	spin_unlock_irqrestore(&priv->lock, flags);
 788
 789	usb_serial_port_softint(port);
 790} /* cypress_send */
 791
 792
 793/* returns how much space is available in the soft buffer */
 794static int cypress_write_room(struct tty_struct *tty)
 795{
 796	struct usb_serial_port *port = tty->driver_data;
 797	struct cypress_private *priv = usb_get_serial_port_data(port);
 798	int room = 0;
 799	unsigned long flags;
 800
 801	spin_lock_irqsave(&priv->lock, flags);
 802	room = kfifo_avail(&priv->write_fifo);
 803	spin_unlock_irqrestore(&priv->lock, flags);
 804
 805	dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
 806	return room;
 807}
 808
 809
 810static int cypress_tiocmget(struct tty_struct *tty)
 811{
 812	struct usb_serial_port *port = tty->driver_data;
 813	struct cypress_private *priv = usb_get_serial_port_data(port);
 814	__u8 status, control;
 815	unsigned int result = 0;
 816	unsigned long flags;
 817
 818	spin_lock_irqsave(&priv->lock, flags);
 819	control = priv->line_control;
 820	status = priv->current_status;
 821	spin_unlock_irqrestore(&priv->lock, flags);
 822
 823	result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
 824		| ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
 825		| ((status & UART_CTS)        ? TIOCM_CTS : 0)
 826		| ((status & UART_DSR)        ? TIOCM_DSR : 0)
 827		| ((status & UART_RI)         ? TIOCM_RI  : 0)
 828		| ((status & UART_CD)         ? TIOCM_CD  : 0);
 829
 830	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
 831
 832	return result;
 833}
 834
 835
 836static int cypress_tiocmset(struct tty_struct *tty,
 837			       unsigned int set, unsigned int clear)
 838{
 839	struct usb_serial_port *port = tty->driver_data;
 840	struct cypress_private *priv = usb_get_serial_port_data(port);
 841	unsigned long flags;
 842
 843	spin_lock_irqsave(&priv->lock, flags);
 844	if (set & TIOCM_RTS)
 845		priv->line_control |= CONTROL_RTS;
 846	if (set & TIOCM_DTR)
 847		priv->line_control |= CONTROL_DTR;
 848	if (clear & TIOCM_RTS)
 849		priv->line_control &= ~CONTROL_RTS;
 850	if (clear & TIOCM_DTR)
 851		priv->line_control &= ~CONTROL_DTR;
 852	priv->cmd_ctrl = 1;
 853	spin_unlock_irqrestore(&priv->lock, flags);
 854
 855	return cypress_write(tty, port, NULL, 0);
 856}
 857
 858static void cypress_earthmate_init_termios(struct tty_struct *tty)
 859{
 860	tty_encode_baud_rate(tty, 4800, 4800);
 861}
 862
 863static void cypress_set_termios(struct tty_struct *tty,
 864	struct usb_serial_port *port, struct ktermios *old_termios)
 865{
 866	struct cypress_private *priv = usb_get_serial_port_data(port);
 867	struct device *dev = &port->dev;
 868	int data_bits, stop_bits, parity_type, parity_enable;
 869	unsigned int cflag;
 870	unsigned long flags;
 871	__u8 oldlines;
 872	int linechange = 0;
 873
 874	/* Unsupported features need clearing */
 875	tty->termios.c_cflag &= ~(CMSPAR|CRTSCTS);
 876
 877	cflag = tty->termios.c_cflag;
 878
 879	/* set number of data bits, parity, stop bits */
 880	/* when parity is disabled the parity type bit is ignored */
 881
 882	/* 1 means 2 stop bits, 0 means 1 stop bit */
 883	stop_bits = cflag & CSTOPB ? 1 : 0;
 884
 885	if (cflag & PARENB) {
 886		parity_enable = 1;
 887		/* 1 means odd parity, 0 means even parity */
 888		parity_type = cflag & PARODD ? 1 : 0;
 889	} else
 890		parity_enable = parity_type = 0;
 891
 892	switch (cflag & CSIZE) {
 893	case CS5:
 894		data_bits = 0;
 895		break;
 896	case CS6:
 897		data_bits = 1;
 898		break;
 899	case CS7:
 900		data_bits = 2;
 901		break;
 902	case CS8:
 903		data_bits = 3;
 904		break;
 905	default:
 906		dev_err(dev, "%s - CSIZE was set, but not CS5-CS8\n", __func__);
 907		data_bits = 3;
 908	}
 909	spin_lock_irqsave(&priv->lock, flags);
 910	oldlines = priv->line_control;
 911	if ((cflag & CBAUD) == B0) {
 912		/* drop dtr and rts */
 913		dev_dbg(dev, "%s - dropping the lines, baud rate 0bps\n", __func__);
 914		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 915	} else
 916		priv->line_control = (CONTROL_DTR | CONTROL_RTS);
 917	spin_unlock_irqrestore(&priv->lock, flags);
 918
 919	dev_dbg(dev, "%s - sending %d stop_bits, %d parity_enable, %d parity_type, %d data_bits (+5)\n",
 920		__func__, stop_bits, parity_enable, parity_type, data_bits);
 921
 922	cypress_serial_control(tty, port, tty_get_baud_rate(tty),
 923			data_bits, stop_bits,
 924			parity_enable, parity_type,
 925			0, CYPRESS_SET_CONFIG);
 926
 927	/* we perform a CYPRESS_GET_CONFIG so that the current settings are
 928	 * filled into the private structure this should confirm that all is
 929	 * working if it returns what we just set */
 930	cypress_serial_control(tty, port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
 931
 932	/* Here we can define custom tty settings for devices; the main tty
 933	 * termios flag base comes from empeg.c */
 934
 935	spin_lock_irqsave(&priv->lock, flags);
 936	if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
 937		dev_dbg(dev, "Using custom termios settings for a baud rate of 4800bps.\n");
 938		/* define custom termios settings for NMEA protocol */
 939
 940		tty->termios.c_iflag /* input modes - */
 941			&= ~(IGNBRK  /* disable ignore break */
 942			| BRKINT     /* disable break causes interrupt */
 943			| PARMRK     /* disable mark parity errors */
 944			| ISTRIP     /* disable clear high bit of input char */
 945			| INLCR      /* disable translate NL to CR */
 946			| IGNCR      /* disable ignore CR */
 947			| ICRNL      /* disable translate CR to NL */
 948			| IXON);     /* disable enable XON/XOFF flow control */
 949
 950		tty->termios.c_oflag /* output modes */
 951			&= ~OPOST;    /* disable postprocess output char */
 952
 953		tty->termios.c_lflag /* line discipline modes */
 954			&= ~(ECHO     /* disable echo input characters */
 955			| ECHONL      /* disable echo new line */
 956			| ICANON      /* disable erase, kill, werase, and rprnt
 957					 special characters */
 958			| ISIG        /* disable interrupt, quit, and suspend
 959					 special characters */
 960			| IEXTEN);    /* disable non-POSIX special characters */
 961	} /* CT_CYPHIDCOM: Application should handle this for device */
 962
 963	linechange = (priv->line_control != oldlines);
 964	spin_unlock_irqrestore(&priv->lock, flags);
 965
 966	/* if necessary, set lines */
 967	if (linechange) {
 968		priv->cmd_ctrl = 1;
 969		cypress_write(tty, port, NULL, 0);
 970	}
 971} /* cypress_set_termios */
 972
 973
 974/* returns amount of data still left in soft buffer */
 975static int cypress_chars_in_buffer(struct tty_struct *tty)
 976{
 977	struct usb_serial_port *port = tty->driver_data;
 978	struct cypress_private *priv = usb_get_serial_port_data(port);
 979	int chars = 0;
 980	unsigned long flags;
 981
 982	spin_lock_irqsave(&priv->lock, flags);
 983	chars = kfifo_len(&priv->write_fifo);
 984	spin_unlock_irqrestore(&priv->lock, flags);
 985
 986	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
 987	return chars;
 988}
 989
 990
 991static void cypress_throttle(struct tty_struct *tty)
 992{
 993	struct usb_serial_port *port = tty->driver_data;
 994	struct cypress_private *priv = usb_get_serial_port_data(port);
 995
 996	spin_lock_irq(&priv->lock);
 997	priv->rx_flags = THROTTLED;
 998	spin_unlock_irq(&priv->lock);
 999}
1000
1001
1002static void cypress_unthrottle(struct tty_struct *tty)
1003{
1004	struct usb_serial_port *port = tty->driver_data;
1005	struct cypress_private *priv = usb_get_serial_port_data(port);
1006	int actually_throttled, result;
1007
1008	spin_lock_irq(&priv->lock);
1009	actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1010	priv->rx_flags = 0;
1011	spin_unlock_irq(&priv->lock);
1012
1013	if (!priv->comm_is_ok)
1014		return;
1015
1016	if (actually_throttled) {
1017		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
1018		if (result) {
1019			dev_err(&port->dev, "%s - failed submitting read urb, "
1020					"error %d\n", __func__, result);
1021			cypress_set_dead(port);
1022		}
1023	}
1024}
1025
1026
1027static void cypress_read_int_callback(struct urb *urb)
1028{
1029	struct usb_serial_port *port = urb->context;
1030	struct cypress_private *priv = usb_get_serial_port_data(port);
1031	struct device *dev = &urb->dev->dev;
1032	struct tty_struct *tty;
1033	unsigned char *data = urb->transfer_buffer;
1034	unsigned long flags;
1035	char tty_flag = TTY_NORMAL;
1036	int bytes = 0;
1037	int result;
1038	int i = 0;
1039	int status = urb->status;
1040
1041	switch (status) {
1042	case 0: /* success */
1043		break;
1044	case -ECONNRESET:
1045	case -ENOENT:
1046	case -ESHUTDOWN:
1047		/* precursor to disconnect so just go away */
1048		return;
1049	case -EPIPE:
1050		/* Can't call usb_clear_halt while in_interrupt */
1051		fallthrough;
1052	default:
1053		/* something ugly is going on... */
1054		dev_err(dev, "%s - unexpected nonzero read status received: %d\n",
1055			__func__, status);
1056		cypress_set_dead(port);
1057		return;
1058	}
1059
1060	spin_lock_irqsave(&priv->lock, flags);
1061	if (priv->rx_flags & THROTTLED) {
1062		dev_dbg(dev, "%s - now throttling\n", __func__);
1063		priv->rx_flags |= ACTUALLY_THROTTLED;
1064		spin_unlock_irqrestore(&priv->lock, flags);
1065		return;
1066	}
1067	spin_unlock_irqrestore(&priv->lock, flags);
1068
1069	tty = tty_port_tty_get(&port->port);
1070	if (!tty) {
1071		dev_dbg(dev, "%s - bad tty pointer - exiting\n", __func__);
1072		return;
1073	}
1074
1075	spin_lock_irqsave(&priv->lock, flags);
1076	result = urb->actual_length;
1077	switch (priv->pkt_fmt) {
1078	default:
1079	case packet_format_1:
1080		/* This is for the CY7C64013... */
1081		priv->current_status = data[0] & 0xF8;
1082		bytes = data[1] + 2;
1083		i = 2;
1084		break;
1085	case packet_format_2:
1086		/* This is for the CY7C63743... */
1087		priv->current_status = data[0] & 0xF8;
1088		bytes = (data[0] & 0x07) + 1;
1089		i = 1;
1090		break;
1091	}
1092	spin_unlock_irqrestore(&priv->lock, flags);
1093	if (result < bytes) {
1094		dev_dbg(dev,
1095			"%s - wrong packet size - received %d bytes but packet said %d bytes\n",
1096			__func__, result, bytes);
1097		goto continue_read;
1098	}
1099
1100	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
1101
1102	spin_lock_irqsave(&priv->lock, flags);
1103	/* check to see if status has changed */
1104	if (priv->current_status != priv->prev_status) {
1105		u8 delta = priv->current_status ^ priv->prev_status;
1106
1107		if (delta & UART_MSR_MASK) {
1108			if (delta & UART_CTS)
1109				port->icount.cts++;
1110			if (delta & UART_DSR)
1111				port->icount.dsr++;
1112			if (delta & UART_RI)
1113				port->icount.rng++;
1114			if (delta & UART_CD)
1115				port->icount.dcd++;
1116
1117			wake_up_interruptible(&port->port.delta_msr_wait);
1118		}
1119
1120		priv->prev_status = priv->current_status;
1121	}
1122	spin_unlock_irqrestore(&priv->lock, flags);
1123
1124	/* hangup, as defined in acm.c... this might be a bad place for it
1125	 * though */
1126	if (tty && !C_CLOCAL(tty) && !(priv->current_status & UART_CD)) {
1127		dev_dbg(dev, "%s - calling hangup\n", __func__);
1128		tty_hangup(tty);
1129		goto continue_read;
1130	}
1131
1132	/* There is one error bit... I'm assuming it is a parity error
1133	 * indicator as the generic firmware will set this bit to 1 if a
1134	 * parity error occurs.
1135	 * I can not find reference to any other error events. */
1136	spin_lock_irqsave(&priv->lock, flags);
1137	if (priv->current_status & CYP_ERROR) {
1138		spin_unlock_irqrestore(&priv->lock, flags);
1139		tty_flag = TTY_PARITY;
1140		dev_dbg(dev, "%s - Parity Error detected\n", __func__);
1141	} else
1142		spin_unlock_irqrestore(&priv->lock, flags);
1143
1144	/* process read if there is data other than line status */
1145	if (bytes > i) {
1146		tty_insert_flip_string_fixed_flag(&port->port, data + i,
1147				tty_flag, bytes - i);
1148		tty_flip_buffer_push(&port->port);
1149	}
1150
1151	spin_lock_irqsave(&priv->lock, flags);
1152	/* control and status byte(s) are also counted */
1153	priv->bytes_in += bytes;
1154	spin_unlock_irqrestore(&priv->lock, flags);
1155
1156continue_read:
1157	tty_kref_put(tty);
1158
1159	/* Continue trying to always read */
1160
1161	if (priv->comm_is_ok) {
1162		usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1163				usb_rcvintpipe(port->serial->dev,
1164					port->interrupt_in_endpointAddress),
1165				port->interrupt_in_urb->transfer_buffer,
1166				port->interrupt_in_urb->transfer_buffer_length,
1167				cypress_read_int_callback, port,
1168				priv->read_urb_interval);
1169		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1170		if (result && result != -EPERM) {
1171			dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
1172				__func__, result);
1173			cypress_set_dead(port);
1174		}
1175	}
1176} /* cypress_read_int_callback */
1177
1178
1179static void cypress_write_int_callback(struct urb *urb)
1180{
1181	struct usb_serial_port *port = urb->context;
1182	struct cypress_private *priv = usb_get_serial_port_data(port);
1183	struct device *dev = &urb->dev->dev;
1184	int status = urb->status;
1185
1186	switch (status) {
1187	case 0:
1188		/* success */
1189		break;
1190	case -ECONNRESET:
1191	case -ENOENT:
1192	case -ESHUTDOWN:
1193		/* this urb is terminated, clean up */
1194		dev_dbg(dev, "%s - urb shutting down with status: %d\n",
1195			__func__, status);
1196		priv->write_urb_in_use = 0;
1197		return;
1198	case -EPIPE:
1199		/* Cannot call usb_clear_halt while in_interrupt */
1200		fallthrough;
1201	default:
1202		dev_err(dev, "%s - unexpected nonzero write status received: %d\n",
1203			__func__, status);
1204		cypress_set_dead(port);
1205		break;
1206	}
1207	priv->write_urb_in_use = 0;
1208
1209	/* send any buffered data */
1210	cypress_send(port);
1211}
1212
1213module_usb_serial_driver(serial_drivers, id_table_combined);
1214
1215MODULE_AUTHOR(DRIVER_AUTHOR);
1216MODULE_DESCRIPTION(DRIVER_DESC);
1217MODULE_LICENSE("GPL");
1218
1219module_param(stats, bool, S_IRUGO | S_IWUSR);
1220MODULE_PARM_DESC(stats, "Enable statistics or not");
1221module_param(interval, int, S_IRUGO | S_IWUSR);
1222MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1223module_param(unstable_bauds, bool, S_IRUGO | S_IWUSR);
1224MODULE_PARM_DESC(unstable_bauds, "Allow unstable baud rates");
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * USB Cypress M8 driver
   4 *
   5 * 	Copyright (C) 2004
   6 * 	    Lonnie Mendez (dignome@gmail.com)
   7 *	Copyright (C) 2003,2004
   8 *	    Neil Whelchel (koyama@firstlight.net)
   9 *
  10 * See Documentation/usb/usb-serial.rst for more information on using this
  11 * driver
  12 *
  13 * See http://geocities.com/i0xox0i for information on this driver and the
  14 * earthmate usb device.
  15 */
  16
  17/* Thanks to Neil Whelchel for writing the first cypress m8 implementation
  18   for linux. */
  19/* Thanks to cypress for providing references for the hid reports. */
  20/* Thanks to Jiang Zhang for providing links and for general help. */
  21/* Code originates and was built up from ftdi_sio, belkin, pl2303 and others.*/
  22
  23
  24#include <linux/kernel.h>
  25#include <linux/errno.h>
  26#include <linux/slab.h>
  27#include <linux/tty.h>
  28#include <linux/tty_driver.h>
  29#include <linux/tty_flip.h>
  30#include <linux/module.h>
  31#include <linux/moduleparam.h>
  32#include <linux/spinlock.h>
  33#include <linux/usb.h>
  34#include <linux/usb/serial.h>
  35#include <linux/serial.h>
  36#include <linux/kfifo.h>
  37#include <linux/delay.h>
  38#include <linux/uaccess.h>
  39#include <asm/unaligned.h>
  40
  41#include "cypress_m8.h"
  42
  43
  44static bool stats;
  45static int interval;
  46static bool unstable_bauds;
  47
  48#define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
  49#define DRIVER_DESC "Cypress USB to Serial Driver"
  50
  51/* write buffer size defines */
  52#define CYPRESS_BUF_SIZE	1024
  53
  54static const struct usb_device_id id_table_earthmate[] = {
  55	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  56	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  57	{ }						/* Terminating entry */
  58};
  59
  60static const struct usb_device_id id_table_cyphidcomrs232[] = {
  61	{ USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  62	{ USB_DEVICE(VENDOR_ID_SAI, PRODUCT_ID_CYPHIDCOM) },
  63	{ USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  64	{ USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
  65	{ }						/* Terminating entry */
  66};
  67
  68static const struct usb_device_id id_table_nokiaca42v2[] = {
  69	{ USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
  70	{ }						/* Terminating entry */
  71};
  72
  73static const struct usb_device_id id_table_combined[] = {
  74	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  75	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  76	{ USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  77	{ USB_DEVICE(VENDOR_ID_SAI, PRODUCT_ID_CYPHIDCOM) },
  78	{ USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  79	{ USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
  80	{ USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
  81	{ }						/* Terminating entry */
  82};
  83
  84MODULE_DEVICE_TABLE(usb, id_table_combined);
  85
  86enum packet_format {
  87	packet_format_1,  /* b0:status, b1:payload count */
  88	packet_format_2   /* b0[7:3]:status, b0[2:0]:payload count */
  89};
  90
  91struct cypress_private {
  92	spinlock_t lock;		   /* private lock */
  93	int chiptype;			   /* identifier of device, for quirks/etc */
  94	int bytes_in;			   /* used for statistics */
  95	int bytes_out;			   /* used for statistics */
  96	int cmd_count;			   /* used for statistics */
  97	int cmd_ctrl;			   /* always set this to 1 before issuing a command */
  98	struct kfifo write_fifo;	   /* write fifo */
  99	int write_urb_in_use;		   /* write urb in use indicator */
 100	int write_urb_interval;            /* interval to use for write urb */
 101	int read_urb_interval;             /* interval to use for read urb */
 102	int comm_is_ok;                    /* true if communication is (still) ok */
 103	__u8 line_control;	   	   /* holds dtr / rts value */
 104	__u8 current_status;	   	   /* received from last read - info on dsr,cts,cd,ri,etc */
 105	__u8 current_config;	   	   /* stores the current configuration byte */
 106	__u8 rx_flags;			   /* throttling - used from whiteheat/ftdi_sio */
 107	enum packet_format pkt_fmt;	   /* format to use for packet send / receive */
 108	int get_cfg_unsafe;		   /* If true, the CYPRESS_GET_CONFIG is unsafe */
 109	int baud_rate;			   /* stores current baud rate in
 110					      integer form */
 111	char prev_status;		   /* used for TIOCMIWAIT */
 112};
 113
 114/* function prototypes for the Cypress USB to serial device */
 115static int  cypress_earthmate_port_probe(struct usb_serial_port *port);
 116static int  cypress_hidcom_port_probe(struct usb_serial_port *port);
 117static int  cypress_ca42v2_port_probe(struct usb_serial_port *port);
 118static void cypress_port_remove(struct usb_serial_port *port);
 119static int  cypress_open(struct tty_struct *tty, struct usb_serial_port *port);
 120static void cypress_close(struct usb_serial_port *port);
 121static void cypress_dtr_rts(struct usb_serial_port *port, int on);
 122static int  cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 123			const unsigned char *buf, int count);
 124static void cypress_send(struct usb_serial_port *port);
 125static unsigned int cypress_write_room(struct tty_struct *tty);
 126static void cypress_earthmate_init_termios(struct tty_struct *tty);
 127static void cypress_set_termios(struct tty_struct *tty,
 128			struct usb_serial_port *port, struct ktermios *old);
 129static int  cypress_tiocmget(struct tty_struct *tty);
 130static int  cypress_tiocmset(struct tty_struct *tty,
 131			unsigned int set, unsigned int clear);
 132static unsigned int cypress_chars_in_buffer(struct tty_struct *tty);
 133static void cypress_throttle(struct tty_struct *tty);
 134static void cypress_unthrottle(struct tty_struct *tty);
 135static void cypress_set_dead(struct usb_serial_port *port);
 136static void cypress_read_int_callback(struct urb *urb);
 137static void cypress_write_int_callback(struct urb *urb);
 138
 139static struct usb_serial_driver cypress_earthmate_device = {
 140	.driver = {
 141		.owner =		THIS_MODULE,
 142		.name =			"earthmate",
 143	},
 144	.description =			"DeLorme Earthmate USB",
 145	.id_table =			id_table_earthmate,
 146	.num_ports =			1,
 147	.port_probe =			cypress_earthmate_port_probe,
 148	.port_remove =			cypress_port_remove,
 149	.open =				cypress_open,
 150	.close =			cypress_close,
 151	.dtr_rts =			cypress_dtr_rts,
 152	.write =			cypress_write,
 153	.write_room =			cypress_write_room,
 154	.init_termios =			cypress_earthmate_init_termios,
 155	.set_termios =			cypress_set_termios,
 156	.tiocmget =			cypress_tiocmget,
 157	.tiocmset =			cypress_tiocmset,
 158	.tiocmiwait =			usb_serial_generic_tiocmiwait,
 159	.chars_in_buffer =		cypress_chars_in_buffer,
 160	.throttle =		 	cypress_throttle,
 161	.unthrottle =			cypress_unthrottle,
 162	.read_int_callback =		cypress_read_int_callback,
 163	.write_int_callback =		cypress_write_int_callback,
 164};
 165
 166static struct usb_serial_driver cypress_hidcom_device = {
 167	.driver = {
 168		.owner =		THIS_MODULE,
 169		.name =			"cyphidcom",
 170	},
 171	.description =			"HID->COM RS232 Adapter",
 172	.id_table =			id_table_cyphidcomrs232,
 173	.num_ports =			1,
 174	.port_probe =			cypress_hidcom_port_probe,
 175	.port_remove =			cypress_port_remove,
 176	.open =				cypress_open,
 177	.close =			cypress_close,
 178	.dtr_rts =			cypress_dtr_rts,
 179	.write =			cypress_write,
 180	.write_room =			cypress_write_room,
 181	.set_termios =			cypress_set_termios,
 182	.tiocmget =			cypress_tiocmget,
 183	.tiocmset =			cypress_tiocmset,
 184	.tiocmiwait =			usb_serial_generic_tiocmiwait,
 185	.chars_in_buffer =		cypress_chars_in_buffer,
 186	.throttle =			cypress_throttle,
 187	.unthrottle =			cypress_unthrottle,
 188	.read_int_callback =		cypress_read_int_callback,
 189	.write_int_callback =		cypress_write_int_callback,
 190};
 191
 192static struct usb_serial_driver cypress_ca42v2_device = {
 193	.driver = {
 194		.owner =		THIS_MODULE,
 195		.name =			"nokiaca42v2",
 196	},
 197	.description =			"Nokia CA-42 V2 Adapter",
 198	.id_table =			id_table_nokiaca42v2,
 199	.num_ports =			1,
 200	.port_probe =			cypress_ca42v2_port_probe,
 201	.port_remove =			cypress_port_remove,
 202	.open =				cypress_open,
 203	.close =			cypress_close,
 204	.dtr_rts =			cypress_dtr_rts,
 205	.write =			cypress_write,
 206	.write_room =			cypress_write_room,
 207	.set_termios =			cypress_set_termios,
 208	.tiocmget =			cypress_tiocmget,
 209	.tiocmset =			cypress_tiocmset,
 210	.tiocmiwait =			usb_serial_generic_tiocmiwait,
 211	.chars_in_buffer =		cypress_chars_in_buffer,
 212	.throttle =			cypress_throttle,
 213	.unthrottle =			cypress_unthrottle,
 214	.read_int_callback =		cypress_read_int_callback,
 215	.write_int_callback =		cypress_write_int_callback,
 216};
 217
 218static struct usb_serial_driver * const serial_drivers[] = {
 219	&cypress_earthmate_device, &cypress_hidcom_device,
 220	&cypress_ca42v2_device, NULL
 221};
 222
 223/*****************************************************************************
 224 * Cypress serial helper functions
 225 *****************************************************************************/
 226
 227/* FRWD Dongle hidcom needs to skip reset and speed checks */
 228static inline bool is_frwd(struct usb_device *dev)
 229{
 230	return ((le16_to_cpu(dev->descriptor.idVendor) == VENDOR_ID_FRWD) &&
 231		(le16_to_cpu(dev->descriptor.idProduct) == PRODUCT_ID_CYPHIDCOM_FRWD));
 232}
 233
 234static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
 235{
 236	struct cypress_private *priv;
 237	priv = usb_get_serial_port_data(port);
 238
 239	if (unstable_bauds)
 240		return new_rate;
 241
 242	/* FRWD Dongle uses 115200 bps */
 243	if (is_frwd(port->serial->dev))
 244		return new_rate;
 245
 246	/*
 247	 * The general purpose firmware for the Cypress M8 allows for
 248	 * a maximum speed of 57600bps (I have no idea whether DeLorme
 249	 * chose to use the general purpose firmware or not), if you
 250	 * need to modify this speed setting for your own project
 251	 * please add your own chiptype and modify the code likewise.
 252	 * The Cypress HID->COM device will work successfully up to
 253	 * 115200bps (but the actual throughput is around 3kBps).
 254	 */
 255	if (port->serial->dev->speed == USB_SPEED_LOW) {
 256		/*
 257		 * Mike Isely <isely@pobox.com> 2-Feb-2008: The
 258		 * Cypress app note that describes this mechanism
 259		 * states the the low-speed part can't handle more
 260		 * than 800 bytes/sec, in which case 4800 baud is the
 261		 * safest speed for a part like that.
 262		 */
 263		if (new_rate > 4800) {
 264			dev_dbg(&port->dev,
 265				"%s - failed setting baud rate, device incapable speed %d\n",
 266				__func__, new_rate);
 267			return -1;
 268		}
 269	}
 270	switch (priv->chiptype) {
 271	case CT_EARTHMATE:
 272		if (new_rate <= 600) {
 273			/* 300 and 600 baud rates are supported under
 274			 * the generic firmware, but are not used with
 275			 * NMEA and SiRF protocols */
 276			dev_dbg(&port->dev,
 277				"%s - failed setting baud rate, unsupported speed of %d on Earthmate GPS\n",
 278				__func__, new_rate);
 279			return -1;
 280		}
 281		break;
 282	default:
 283		break;
 284	}
 285	return new_rate;
 286}
 287
 288
 289/* This function can either set or retrieve the current serial line settings */
 290static int cypress_serial_control(struct tty_struct *tty,
 291	struct usb_serial_port *port, speed_t baud_rate, int data_bits,
 292	int stop_bits, int parity_enable, int parity_type, int reset,
 293	int cypress_request_type)
 294{
 295	int new_baudrate = 0, retval = 0, tries = 0;
 296	struct cypress_private *priv;
 297	struct device *dev = &port->dev;
 298	u8 *feature_buffer;
 299	const unsigned int feature_len = 5;
 300	unsigned long flags;
 301
 302	priv = usb_get_serial_port_data(port);
 303
 304	if (!priv->comm_is_ok)
 305		return -ENODEV;
 306
 307	feature_buffer = kcalloc(feature_len, sizeof(u8), GFP_KERNEL);
 308	if (!feature_buffer)
 309		return -ENOMEM;
 310
 311	switch (cypress_request_type) {
 312	case CYPRESS_SET_CONFIG:
 313		/* 0 means 'Hang up' so doesn't change the true bit rate */
 314		new_baudrate = priv->baud_rate;
 315		if (baud_rate && baud_rate != priv->baud_rate) {
 316			dev_dbg(dev, "%s - baud rate is changing\n", __func__);
 317			retval = analyze_baud_rate(port, baud_rate);
 318			if (retval >= 0) {
 319				new_baudrate = retval;
 320				dev_dbg(dev, "%s - New baud rate set to %d\n",
 321					__func__, new_baudrate);
 322			}
 323		}
 324		dev_dbg(dev, "%s - baud rate is being sent as %d\n", __func__,
 325			new_baudrate);
 326
 327		/* fill the feature_buffer with new configuration */
 328		put_unaligned_le32(new_baudrate, feature_buffer);
 329		feature_buffer[4] |= data_bits - 5;   /* assign data bits in 2 bit space ( max 3 ) */
 330		/* 1 bit gap */
 331		feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
 332		feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
 333		feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
 334		/* 1 bit gap */
 335		feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
 336
 337		dev_dbg(dev, "%s - device is being sent this feature report:\n", __func__);
 338		dev_dbg(dev, "%s - %02X - %02X - %02X - %02X - %02X\n", __func__,
 339			feature_buffer[0], feature_buffer[1],
 340			feature_buffer[2], feature_buffer[3],
 341			feature_buffer[4]);
 342
 343		do {
 344			retval = usb_control_msg(port->serial->dev,
 345					usb_sndctrlpipe(port->serial->dev, 0),
 346					HID_REQ_SET_REPORT,
 347					USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 348					0x0300, 0, feature_buffer,
 349					feature_len, 500);
 350
 351			if (tries++ >= 3)
 352				break;
 353
 354		} while (retval != feature_len &&
 355			 retval != -ENODEV);
 356
 357		if (retval != feature_len) {
 358			dev_err(dev, "%s - failed sending serial line settings - %d\n",
 359				__func__, retval);
 360			cypress_set_dead(port);
 361		} else {
 362			spin_lock_irqsave(&priv->lock, flags);
 363			priv->baud_rate = new_baudrate;
 364			priv->current_config = feature_buffer[4];
 365			spin_unlock_irqrestore(&priv->lock, flags);
 366			/* If we asked for a speed change encode it */
 367			if (baud_rate)
 368				tty_encode_baud_rate(tty,
 369					new_baudrate, new_baudrate);
 370		}
 371	break;
 372	case CYPRESS_GET_CONFIG:
 373		if (priv->get_cfg_unsafe) {
 374			/* Not implemented for this device,
 375			   and if we try to do it we're likely
 376			   to crash the hardware. */
 377			retval = -ENOTTY;
 378			goto out;
 379		}
 380		dev_dbg(dev, "%s - retrieving serial line settings\n", __func__);
 381		do {
 382			retval = usb_control_msg(port->serial->dev,
 383					usb_rcvctrlpipe(port->serial->dev, 0),
 384					HID_REQ_GET_REPORT,
 385					USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 386					0x0300, 0, feature_buffer,
 387					feature_len, 500);
 388
 389			if (tries++ >= 3)
 390				break;
 391		} while (retval != feature_len
 392						&& retval != -ENODEV);
 393
 394		if (retval != feature_len) {
 395			dev_err(dev, "%s - failed to retrieve serial line settings - %d\n",
 396				__func__, retval);
 397			cypress_set_dead(port);
 398			goto out;
 399		} else {
 400			spin_lock_irqsave(&priv->lock, flags);
 401			/* store the config in one byte, and later
 402			   use bit masks to check values */
 403			priv->current_config = feature_buffer[4];
 404			priv->baud_rate = get_unaligned_le32(feature_buffer);
 405			spin_unlock_irqrestore(&priv->lock, flags);
 406		}
 407	}
 408	spin_lock_irqsave(&priv->lock, flags);
 409	++priv->cmd_count;
 410	spin_unlock_irqrestore(&priv->lock, flags);
 411out:
 412	kfree(feature_buffer);
 413	return retval;
 414} /* cypress_serial_control */
 415
 416
 417static void cypress_set_dead(struct usb_serial_port *port)
 418{
 419	struct cypress_private *priv = usb_get_serial_port_data(port);
 420	unsigned long flags;
 421
 422	spin_lock_irqsave(&priv->lock, flags);
 423	if (!priv->comm_is_ok) {
 424		spin_unlock_irqrestore(&priv->lock, flags);
 425		return;
 426	}
 427	priv->comm_is_ok = 0;
 428	spin_unlock_irqrestore(&priv->lock, flags);
 429
 430	dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
 431		"interval might be too short\n", port->port_number);
 432}
 433
 434
 435/*****************************************************************************
 436 * Cypress serial driver functions
 437 *****************************************************************************/
 438
 439
 440static int cypress_generic_port_probe(struct usb_serial_port *port)
 441{
 442	struct usb_serial *serial = port->serial;
 443	struct cypress_private *priv;
 444
 445	if (!port->interrupt_out_urb || !port->interrupt_in_urb) {
 446		dev_err(&port->dev, "required endpoint is missing\n");
 447		return -ENODEV;
 448	}
 449
 450	priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL);
 451	if (!priv)
 452		return -ENOMEM;
 453
 454	priv->comm_is_ok = !0;
 455	spin_lock_init(&priv->lock);
 456	if (kfifo_alloc(&priv->write_fifo, CYPRESS_BUF_SIZE, GFP_KERNEL)) {
 457		kfree(priv);
 458		return -ENOMEM;
 459	}
 460
 461	/* Skip reset for FRWD device. It is a workaound:
 462	   device hangs if it receives SET_CONFIGURE in Configured
 463	   state. */
 464	if (!is_frwd(serial->dev))
 465		usb_reset_configuration(serial->dev);
 466
 467	priv->cmd_ctrl = 0;
 468	priv->line_control = 0;
 469	priv->rx_flags = 0;
 470	/* Default packet format setting is determined by packet size.
 471	   Anything with a size larger then 9 must have a separate
 472	   count field since the 3 bit count field is otherwise too
 473	   small.  Otherwise we can use the slightly more compact
 474	   format.  This is in accordance with the cypress_m8 serial
 475	   converter app note. */
 476	if (port->interrupt_out_size > 9)
 477		priv->pkt_fmt = packet_format_1;
 478	else
 479		priv->pkt_fmt = packet_format_2;
 480
 481	if (interval > 0) {
 482		priv->write_urb_interval = interval;
 483		priv->read_urb_interval = interval;
 484		dev_dbg(&port->dev, "%s - read & write intervals forced to %d\n",
 485			__func__, interval);
 486	} else {
 487		priv->write_urb_interval = port->interrupt_out_urb->interval;
 488		priv->read_urb_interval = port->interrupt_in_urb->interval;
 489		dev_dbg(&port->dev, "%s - intervals: read=%d write=%d\n",
 490			__func__, priv->read_urb_interval,
 491			priv->write_urb_interval);
 492	}
 493	usb_set_serial_port_data(port, priv);
 494
 495	port->port.drain_delay = 256;
 496
 497	return 0;
 498}
 499
 500
 501static int cypress_earthmate_port_probe(struct usb_serial_port *port)
 502{
 503	struct usb_serial *serial = port->serial;
 504	struct cypress_private *priv;
 505	int ret;
 506
 507	ret = cypress_generic_port_probe(port);
 508	if (ret) {
 509		dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 510		return ret;
 511	}
 512
 513	priv = usb_get_serial_port_data(port);
 514	priv->chiptype = CT_EARTHMATE;
 515	/* All Earthmate devices use the separated-count packet
 516	   format!  Idiotic. */
 517	priv->pkt_fmt = packet_format_1;
 518	if (serial->dev->descriptor.idProduct !=
 519				cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
 520		/* The old original USB Earthmate seemed able to
 521		   handle GET_CONFIG requests; everything they've
 522		   produced since that time crashes if this command is
 523		   attempted :-( */
 524		dev_dbg(&port->dev,
 525			"%s - Marking this device as unsafe for GET_CONFIG commands\n",
 526			__func__);
 527		priv->get_cfg_unsafe = !0;
 528	}
 529
 530	return 0;
 531}
 532
 533static int cypress_hidcom_port_probe(struct usb_serial_port *port)
 534{
 535	struct cypress_private *priv;
 536	int ret;
 537
 538	ret = cypress_generic_port_probe(port);
 539	if (ret) {
 540		dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 541		return ret;
 542	}
 543
 544	priv = usb_get_serial_port_data(port);
 545	priv->chiptype = CT_CYPHIDCOM;
 546
 547	return 0;
 548}
 549
 550static int cypress_ca42v2_port_probe(struct usb_serial_port *port)
 551{
 552	struct cypress_private *priv;
 553	int ret;
 554
 555	ret = cypress_generic_port_probe(port);
 556	if (ret) {
 557		dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 558		return ret;
 559	}
 560
 561	priv = usb_get_serial_port_data(port);
 562	priv->chiptype = CT_CA42V2;
 563
 564	return 0;
 565}
 566
 567static void cypress_port_remove(struct usb_serial_port *port)
 568{
 569	struct cypress_private *priv;
 570
 571	priv = usb_get_serial_port_data(port);
 572
 573	kfifo_free(&priv->write_fifo);
 574	kfree(priv);
 
 
 575}
 576
 577static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port)
 578{
 579	struct cypress_private *priv = usb_get_serial_port_data(port);
 580	struct usb_serial *serial = port->serial;
 581	unsigned long flags;
 582	int result = 0;
 583
 584	if (!priv->comm_is_ok)
 585		return -EIO;
 586
 587	/* clear halts before open */
 588	usb_clear_halt(serial->dev, 0x81);
 589	usb_clear_halt(serial->dev, 0x02);
 590
 591	spin_lock_irqsave(&priv->lock, flags);
 592	/* reset read/write statistics */
 593	priv->bytes_in = 0;
 594	priv->bytes_out = 0;
 595	priv->cmd_count = 0;
 596	priv->rx_flags = 0;
 597	spin_unlock_irqrestore(&priv->lock, flags);
 598
 599	/* Set termios */
 600	cypress_send(port);
 601
 602	if (tty)
 603		cypress_set_termios(tty, port, NULL);
 604
 605	/* setup the port and start reading from the device */
 606	usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 607		usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 608		port->interrupt_in_urb->transfer_buffer,
 609		port->interrupt_in_urb->transfer_buffer_length,
 610		cypress_read_int_callback, port, priv->read_urb_interval);
 611	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 612
 613	if (result) {
 614		dev_err(&port->dev,
 615			"%s - failed submitting read urb, error %d\n",
 616							__func__, result);
 617		cypress_set_dead(port);
 618	}
 619
 620	return result;
 621} /* cypress_open */
 622
 623static void cypress_dtr_rts(struct usb_serial_port *port, int on)
 624{
 625	struct cypress_private *priv = usb_get_serial_port_data(port);
 626	/* drop dtr and rts */
 627	spin_lock_irq(&priv->lock);
 628	if (on == 0)
 629		priv->line_control = 0;
 630	else 
 631		priv->line_control = CONTROL_DTR | CONTROL_RTS;
 632	priv->cmd_ctrl = 1;
 633	spin_unlock_irq(&priv->lock);
 634	cypress_write(NULL, port, NULL, 0);
 635}
 636
 637static void cypress_close(struct usb_serial_port *port)
 638{
 639	struct cypress_private *priv = usb_get_serial_port_data(port);
 640	unsigned long flags;
 641
 642	spin_lock_irqsave(&priv->lock, flags);
 643	kfifo_reset_out(&priv->write_fifo);
 644	spin_unlock_irqrestore(&priv->lock, flags);
 645
 646	dev_dbg(&port->dev, "%s - stopping urbs\n", __func__);
 647	usb_kill_urb(port->interrupt_in_urb);
 648	usb_kill_urb(port->interrupt_out_urb);
 649
 650	if (stats)
 651		dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
 652			priv->bytes_in, priv->bytes_out, priv->cmd_count);
 653} /* cypress_close */
 654
 655
 656static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 657					const unsigned char *buf, int count)
 658{
 659	struct cypress_private *priv = usb_get_serial_port_data(port);
 660
 661	dev_dbg(&port->dev, "%s - %d bytes\n", __func__, count);
 662
 663	/* line control commands, which need to be executed immediately,
 664	   are not put into the buffer for obvious reasons.
 665	 */
 666	if (priv->cmd_ctrl) {
 667		count = 0;
 668		goto finish;
 669	}
 670
 671	if (!count)
 672		return count;
 673
 674	count = kfifo_in_locked(&priv->write_fifo, buf, count, &priv->lock);
 675
 676finish:
 677	cypress_send(port);
 678
 679	return count;
 680} /* cypress_write */
 681
 682
 683static void cypress_send(struct usb_serial_port *port)
 684{
 685	int count = 0, result, offset, actual_size;
 686	struct cypress_private *priv = usb_get_serial_port_data(port);
 687	struct device *dev = &port->dev;
 688	unsigned long flags;
 689
 690	if (!priv->comm_is_ok)
 691		return;
 692
 693	dev_dbg(dev, "%s - interrupt out size is %d\n", __func__,
 694		port->interrupt_out_size);
 695
 696	spin_lock_irqsave(&priv->lock, flags);
 697	if (priv->write_urb_in_use) {
 698		dev_dbg(dev, "%s - can't write, urb in use\n", __func__);
 699		spin_unlock_irqrestore(&priv->lock, flags);
 700		return;
 701	}
 702	spin_unlock_irqrestore(&priv->lock, flags);
 703
 704	/* clear buffer */
 705	memset(port->interrupt_out_urb->transfer_buffer, 0,
 706						port->interrupt_out_size);
 707
 708	spin_lock_irqsave(&priv->lock, flags);
 709	switch (priv->pkt_fmt) {
 710	default:
 711	case packet_format_1:
 712		/* this is for the CY7C64013... */
 713		offset = 2;
 714		port->interrupt_out_buffer[0] = priv->line_control;
 715		break;
 716	case packet_format_2:
 717		/* this is for the CY7C63743... */
 718		offset = 1;
 719		port->interrupt_out_buffer[0] = priv->line_control;
 720		break;
 721	}
 722
 723	if (priv->line_control & CONTROL_RESET)
 724		priv->line_control &= ~CONTROL_RESET;
 725
 726	if (priv->cmd_ctrl) {
 727		priv->cmd_count++;
 728		dev_dbg(dev, "%s - line control command being issued\n", __func__);
 729		spin_unlock_irqrestore(&priv->lock, flags);
 730		goto send;
 731	} else
 732		spin_unlock_irqrestore(&priv->lock, flags);
 733
 734	count = kfifo_out_locked(&priv->write_fifo,
 735					&port->interrupt_out_buffer[offset],
 736					port->interrupt_out_size - offset,
 737					&priv->lock);
 738	if (count == 0)
 739		return;
 740
 741	switch (priv->pkt_fmt) {
 742	default:
 743	case packet_format_1:
 744		port->interrupt_out_buffer[1] = count;
 745		break;
 746	case packet_format_2:
 747		port->interrupt_out_buffer[0] |= count;
 748	}
 749
 750	dev_dbg(dev, "%s - count is %d\n", __func__, count);
 751
 752send:
 753	spin_lock_irqsave(&priv->lock, flags);
 754	priv->write_urb_in_use = 1;
 755	spin_unlock_irqrestore(&priv->lock, flags);
 756
 757	if (priv->cmd_ctrl)
 758		actual_size = 1;
 759	else
 760		actual_size = count +
 761			      (priv->pkt_fmt == packet_format_1 ? 2 : 1);
 762
 763	usb_serial_debug_data(dev, __func__, port->interrupt_out_size,
 764			      port->interrupt_out_urb->transfer_buffer);
 765
 766	usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
 767		usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
 768		port->interrupt_out_buffer, actual_size,
 769		cypress_write_int_callback, port, priv->write_urb_interval);
 770	result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
 771	if (result) {
 772		dev_err_console(port,
 773				"%s - failed submitting write urb, error %d\n",
 774							__func__, result);
 775		priv->write_urb_in_use = 0;
 776		cypress_set_dead(port);
 777	}
 778
 779	spin_lock_irqsave(&priv->lock, flags);
 780	if (priv->cmd_ctrl)
 781		priv->cmd_ctrl = 0;
 782
 783	/* do not count the line control and size bytes */
 784	priv->bytes_out += count;
 785	spin_unlock_irqrestore(&priv->lock, flags);
 786
 787	usb_serial_port_softint(port);
 788} /* cypress_send */
 789
 790
 791/* returns how much space is available in the soft buffer */
 792static unsigned int cypress_write_room(struct tty_struct *tty)
 793{
 794	struct usb_serial_port *port = tty->driver_data;
 795	struct cypress_private *priv = usb_get_serial_port_data(port);
 796	unsigned int room;
 797	unsigned long flags;
 798
 799	spin_lock_irqsave(&priv->lock, flags);
 800	room = kfifo_avail(&priv->write_fifo);
 801	spin_unlock_irqrestore(&priv->lock, flags);
 802
 803	dev_dbg(&port->dev, "%s - returns %u\n", __func__, room);
 804	return room;
 805}
 806
 807
 808static int cypress_tiocmget(struct tty_struct *tty)
 809{
 810	struct usb_serial_port *port = tty->driver_data;
 811	struct cypress_private *priv = usb_get_serial_port_data(port);
 812	__u8 status, control;
 813	unsigned int result = 0;
 814	unsigned long flags;
 815
 816	spin_lock_irqsave(&priv->lock, flags);
 817	control = priv->line_control;
 818	status = priv->current_status;
 819	spin_unlock_irqrestore(&priv->lock, flags);
 820
 821	result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
 822		| ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
 823		| ((status & UART_CTS)        ? TIOCM_CTS : 0)
 824		| ((status & UART_DSR)        ? TIOCM_DSR : 0)
 825		| ((status & UART_RI)         ? TIOCM_RI  : 0)
 826		| ((status & UART_CD)         ? TIOCM_CD  : 0);
 827
 828	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
 829
 830	return result;
 831}
 832
 833
 834static int cypress_tiocmset(struct tty_struct *tty,
 835			       unsigned int set, unsigned int clear)
 836{
 837	struct usb_serial_port *port = tty->driver_data;
 838	struct cypress_private *priv = usb_get_serial_port_data(port);
 839	unsigned long flags;
 840
 841	spin_lock_irqsave(&priv->lock, flags);
 842	if (set & TIOCM_RTS)
 843		priv->line_control |= CONTROL_RTS;
 844	if (set & TIOCM_DTR)
 845		priv->line_control |= CONTROL_DTR;
 846	if (clear & TIOCM_RTS)
 847		priv->line_control &= ~CONTROL_RTS;
 848	if (clear & TIOCM_DTR)
 849		priv->line_control &= ~CONTROL_DTR;
 850	priv->cmd_ctrl = 1;
 851	spin_unlock_irqrestore(&priv->lock, flags);
 852
 853	return cypress_write(tty, port, NULL, 0);
 854}
 855
 856static void cypress_earthmate_init_termios(struct tty_struct *tty)
 857{
 858	tty_encode_baud_rate(tty, 4800, 4800);
 859}
 860
 861static void cypress_set_termios(struct tty_struct *tty,
 862	struct usb_serial_port *port, struct ktermios *old_termios)
 863{
 864	struct cypress_private *priv = usb_get_serial_port_data(port);
 865	struct device *dev = &port->dev;
 866	int data_bits, stop_bits, parity_type, parity_enable;
 867	unsigned int cflag;
 868	unsigned long flags;
 869	__u8 oldlines;
 870	int linechange = 0;
 871
 872	/* Unsupported features need clearing */
 873	tty->termios.c_cflag &= ~(CMSPAR|CRTSCTS);
 874
 875	cflag = tty->termios.c_cflag;
 876
 877	/* set number of data bits, parity, stop bits */
 878	/* when parity is disabled the parity type bit is ignored */
 879
 880	/* 1 means 2 stop bits, 0 means 1 stop bit */
 881	stop_bits = cflag & CSTOPB ? 1 : 0;
 882
 883	if (cflag & PARENB) {
 884		parity_enable = 1;
 885		/* 1 means odd parity, 0 means even parity */
 886		parity_type = cflag & PARODD ? 1 : 0;
 887	} else
 888		parity_enable = parity_type = 0;
 889
 890	data_bits = tty_get_char_size(cflag);
 891
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 892	spin_lock_irqsave(&priv->lock, flags);
 893	oldlines = priv->line_control;
 894	if ((cflag & CBAUD) == B0) {
 895		/* drop dtr and rts */
 896		dev_dbg(dev, "%s - dropping the lines, baud rate 0bps\n", __func__);
 897		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 898	} else
 899		priv->line_control = (CONTROL_DTR | CONTROL_RTS);
 900	spin_unlock_irqrestore(&priv->lock, flags);
 901
 902	dev_dbg(dev, "%s - sending %d stop_bits, %d parity_enable, %d parity_type, %d data_bits (+5)\n",
 903		__func__, stop_bits, parity_enable, parity_type, data_bits);
 904
 905	cypress_serial_control(tty, port, tty_get_baud_rate(tty),
 906			data_bits, stop_bits,
 907			parity_enable, parity_type,
 908			0, CYPRESS_SET_CONFIG);
 909
 910	/* we perform a CYPRESS_GET_CONFIG so that the current settings are
 911	 * filled into the private structure this should confirm that all is
 912	 * working if it returns what we just set */
 913	cypress_serial_control(tty, port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
 914
 915	/* Here we can define custom tty settings for devices; the main tty
 916	 * termios flag base comes from empeg.c */
 917
 918	spin_lock_irqsave(&priv->lock, flags);
 919	if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
 920		dev_dbg(dev, "Using custom termios settings for a baud rate of 4800bps.\n");
 921		/* define custom termios settings for NMEA protocol */
 922
 923		tty->termios.c_iflag /* input modes - */
 924			&= ~(IGNBRK  /* disable ignore break */
 925			| BRKINT     /* disable break causes interrupt */
 926			| PARMRK     /* disable mark parity errors */
 927			| ISTRIP     /* disable clear high bit of input char */
 928			| INLCR      /* disable translate NL to CR */
 929			| IGNCR      /* disable ignore CR */
 930			| ICRNL      /* disable translate CR to NL */
 931			| IXON);     /* disable enable XON/XOFF flow control */
 932
 933		tty->termios.c_oflag /* output modes */
 934			&= ~OPOST;    /* disable postprocess output char */
 935
 936		tty->termios.c_lflag /* line discipline modes */
 937			&= ~(ECHO     /* disable echo input characters */
 938			| ECHONL      /* disable echo new line */
 939			| ICANON      /* disable erase, kill, werase, and rprnt
 940					 special characters */
 941			| ISIG        /* disable interrupt, quit, and suspend
 942					 special characters */
 943			| IEXTEN);    /* disable non-POSIX special characters */
 944	} /* CT_CYPHIDCOM: Application should handle this for device */
 945
 946	linechange = (priv->line_control != oldlines);
 947	spin_unlock_irqrestore(&priv->lock, flags);
 948
 949	/* if necessary, set lines */
 950	if (linechange) {
 951		priv->cmd_ctrl = 1;
 952		cypress_write(tty, port, NULL, 0);
 953	}
 954} /* cypress_set_termios */
 955
 956
 957/* returns amount of data still left in soft buffer */
 958static unsigned int cypress_chars_in_buffer(struct tty_struct *tty)
 959{
 960	struct usb_serial_port *port = tty->driver_data;
 961	struct cypress_private *priv = usb_get_serial_port_data(port);
 962	unsigned int chars;
 963	unsigned long flags;
 964
 965	spin_lock_irqsave(&priv->lock, flags);
 966	chars = kfifo_len(&priv->write_fifo);
 967	spin_unlock_irqrestore(&priv->lock, flags);
 968
 969	dev_dbg(&port->dev, "%s - returns %u\n", __func__, chars);
 970	return chars;
 971}
 972
 973
 974static void cypress_throttle(struct tty_struct *tty)
 975{
 976	struct usb_serial_port *port = tty->driver_data;
 977	struct cypress_private *priv = usb_get_serial_port_data(port);
 978
 979	spin_lock_irq(&priv->lock);
 980	priv->rx_flags = THROTTLED;
 981	spin_unlock_irq(&priv->lock);
 982}
 983
 984
 985static void cypress_unthrottle(struct tty_struct *tty)
 986{
 987	struct usb_serial_port *port = tty->driver_data;
 988	struct cypress_private *priv = usb_get_serial_port_data(port);
 989	int actually_throttled, result;
 990
 991	spin_lock_irq(&priv->lock);
 992	actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
 993	priv->rx_flags = 0;
 994	spin_unlock_irq(&priv->lock);
 995
 996	if (!priv->comm_is_ok)
 997		return;
 998
 999	if (actually_throttled) {
1000		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
1001		if (result) {
1002			dev_err(&port->dev, "%s - failed submitting read urb, "
1003					"error %d\n", __func__, result);
1004			cypress_set_dead(port);
1005		}
1006	}
1007}
1008
1009
1010static void cypress_read_int_callback(struct urb *urb)
1011{
1012	struct usb_serial_port *port = urb->context;
1013	struct cypress_private *priv = usb_get_serial_port_data(port);
1014	struct device *dev = &urb->dev->dev;
1015	struct tty_struct *tty;
1016	unsigned char *data = urb->transfer_buffer;
1017	unsigned long flags;
1018	char tty_flag = TTY_NORMAL;
1019	int bytes = 0;
1020	int result;
1021	int i = 0;
1022	int status = urb->status;
1023
1024	switch (status) {
1025	case 0: /* success */
1026		break;
1027	case -ECONNRESET:
1028	case -ENOENT:
1029	case -ESHUTDOWN:
1030		/* precursor to disconnect so just go away */
1031		return;
1032	case -EPIPE:
1033		/* Can't call usb_clear_halt while in_interrupt */
1034		fallthrough;
1035	default:
1036		/* something ugly is going on... */
1037		dev_err(dev, "%s - unexpected nonzero read status received: %d\n",
1038			__func__, status);
1039		cypress_set_dead(port);
1040		return;
1041	}
1042
1043	spin_lock_irqsave(&priv->lock, flags);
1044	if (priv->rx_flags & THROTTLED) {
1045		dev_dbg(dev, "%s - now throttling\n", __func__);
1046		priv->rx_flags |= ACTUALLY_THROTTLED;
1047		spin_unlock_irqrestore(&priv->lock, flags);
1048		return;
1049	}
1050	spin_unlock_irqrestore(&priv->lock, flags);
1051
1052	tty = tty_port_tty_get(&port->port);
1053	if (!tty) {
1054		dev_dbg(dev, "%s - bad tty pointer - exiting\n", __func__);
1055		return;
1056	}
1057
1058	spin_lock_irqsave(&priv->lock, flags);
1059	result = urb->actual_length;
1060	switch (priv->pkt_fmt) {
1061	default:
1062	case packet_format_1:
1063		/* This is for the CY7C64013... */
1064		priv->current_status = data[0] & 0xF8;
1065		bytes = data[1] + 2;
1066		i = 2;
1067		break;
1068	case packet_format_2:
1069		/* This is for the CY7C63743... */
1070		priv->current_status = data[0] & 0xF8;
1071		bytes = (data[0] & 0x07) + 1;
1072		i = 1;
1073		break;
1074	}
1075	spin_unlock_irqrestore(&priv->lock, flags);
1076	if (result < bytes) {
1077		dev_dbg(dev,
1078			"%s - wrong packet size - received %d bytes but packet said %d bytes\n",
1079			__func__, result, bytes);
1080		goto continue_read;
1081	}
1082
1083	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
1084
1085	spin_lock_irqsave(&priv->lock, flags);
1086	/* check to see if status has changed */
1087	if (priv->current_status != priv->prev_status) {
1088		u8 delta = priv->current_status ^ priv->prev_status;
1089
1090		if (delta & UART_MSR_MASK) {
1091			if (delta & UART_CTS)
1092				port->icount.cts++;
1093			if (delta & UART_DSR)
1094				port->icount.dsr++;
1095			if (delta & UART_RI)
1096				port->icount.rng++;
1097			if (delta & UART_CD)
1098				port->icount.dcd++;
1099
1100			wake_up_interruptible(&port->port.delta_msr_wait);
1101		}
1102
1103		priv->prev_status = priv->current_status;
1104	}
1105	spin_unlock_irqrestore(&priv->lock, flags);
1106
1107	/* hangup, as defined in acm.c... this might be a bad place for it
1108	 * though */
1109	if (tty && !C_CLOCAL(tty) && !(priv->current_status & UART_CD)) {
1110		dev_dbg(dev, "%s - calling hangup\n", __func__);
1111		tty_hangup(tty);
1112		goto continue_read;
1113	}
1114
1115	/* There is one error bit... I'm assuming it is a parity error
1116	 * indicator as the generic firmware will set this bit to 1 if a
1117	 * parity error occurs.
1118	 * I can not find reference to any other error events. */
1119	spin_lock_irqsave(&priv->lock, flags);
1120	if (priv->current_status & CYP_ERROR) {
1121		spin_unlock_irqrestore(&priv->lock, flags);
1122		tty_flag = TTY_PARITY;
1123		dev_dbg(dev, "%s - Parity Error detected\n", __func__);
1124	} else
1125		spin_unlock_irqrestore(&priv->lock, flags);
1126
1127	/* process read if there is data other than line status */
1128	if (bytes > i) {
1129		tty_insert_flip_string_fixed_flag(&port->port, data + i,
1130				tty_flag, bytes - i);
1131		tty_flip_buffer_push(&port->port);
1132	}
1133
1134	spin_lock_irqsave(&priv->lock, flags);
1135	/* control and status byte(s) are also counted */
1136	priv->bytes_in += bytes;
1137	spin_unlock_irqrestore(&priv->lock, flags);
1138
1139continue_read:
1140	tty_kref_put(tty);
1141
1142	/* Continue trying to always read */
1143
1144	if (priv->comm_is_ok) {
1145		usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1146				usb_rcvintpipe(port->serial->dev,
1147					port->interrupt_in_endpointAddress),
1148				port->interrupt_in_urb->transfer_buffer,
1149				port->interrupt_in_urb->transfer_buffer_length,
1150				cypress_read_int_callback, port,
1151				priv->read_urb_interval);
1152		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1153		if (result && result != -EPERM) {
1154			dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
1155				__func__, result);
1156			cypress_set_dead(port);
1157		}
1158	}
1159} /* cypress_read_int_callback */
1160
1161
1162static void cypress_write_int_callback(struct urb *urb)
1163{
1164	struct usb_serial_port *port = urb->context;
1165	struct cypress_private *priv = usb_get_serial_port_data(port);
1166	struct device *dev = &urb->dev->dev;
1167	int status = urb->status;
1168
1169	switch (status) {
1170	case 0:
1171		/* success */
1172		break;
1173	case -ECONNRESET:
1174	case -ENOENT:
1175	case -ESHUTDOWN:
1176		/* this urb is terminated, clean up */
1177		dev_dbg(dev, "%s - urb shutting down with status: %d\n",
1178			__func__, status);
1179		priv->write_urb_in_use = 0;
1180		return;
1181	case -EPIPE:
1182		/* Cannot call usb_clear_halt while in_interrupt */
1183		fallthrough;
1184	default:
1185		dev_err(dev, "%s - unexpected nonzero write status received: %d\n",
1186			__func__, status);
1187		cypress_set_dead(port);
1188		break;
1189	}
1190	priv->write_urb_in_use = 0;
1191
1192	/* send any buffered data */
1193	cypress_send(port);
1194}
1195
1196module_usb_serial_driver(serial_drivers, id_table_combined);
1197
1198MODULE_AUTHOR(DRIVER_AUTHOR);
1199MODULE_DESCRIPTION(DRIVER_DESC);
1200MODULE_LICENSE("GPL");
1201
1202module_param(stats, bool, S_IRUGO | S_IWUSR);
1203MODULE_PARM_DESC(stats, "Enable statistics or not");
1204module_param(interval, int, S_IRUGO | S_IWUSR);
1205MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1206module_param(unstable_bauds, bool, S_IRUGO | S_IWUSR);
1207MODULE_PARM_DESC(unstable_bauds, "Allow unstable baud rates");