xref: /linux/drivers/usb/serial/cyberjack.c (revision d2912cb15bdda8ba4a5dd73396ad62641af2f520)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  REINER SCT cyberJack pinpad/e-com USB Chipcard Reader Driver
4  *
5  *  Copyright (C) 2001  REINER SCT
6  *  Author: Matthias Bruestle
7  *
8  *  Contact: support@reiner-sct.com (see MAINTAINERS)
9  *
10  *  This program is largely derived from work by the linux-usb group
11  *  and associated source files.  Please see the usb/serial files for
12  *  individual credits and copyrights.
13  *
14  *  Thanks to Greg Kroah-Hartman (greg@kroah.com) for his help and
15  *  patience.
16  *
17  *  In case of problems, please write to the contact e-mail address
18  *  mentioned above.
19  *
20  *  Please note that later models of the cyberjack reader family are
21  *  supported by a libusb-based userspace device driver.
22  *
23  *  Homepage: http://www.reiner-sct.de/support/treiber_cyberjack.php#linux
24  */
25 
26 
27 #include <linux/kernel.h>
28 #include <linux/errno.h>
29 #include <linux/slab.h>
30 #include <linux/tty.h>
31 #include <linux/tty_driver.h>
32 #include <linux/tty_flip.h>
33 #include <linux/module.h>
34 #include <linux/spinlock.h>
35 #include <linux/uaccess.h>
36 #include <linux/usb.h>
37 #include <linux/usb/serial.h>
38 
39 #define CYBERJACK_LOCAL_BUF_SIZE 32
40 
41 #define DRIVER_AUTHOR "Matthias Bruestle"
42 #define DRIVER_DESC "REINER SCT cyberJack pinpad/e-com USB Chipcard Reader Driver"
43 
44 
45 #define CYBERJACK_VENDOR_ID	0x0C4B
46 #define CYBERJACK_PRODUCT_ID	0x0100
47 
48 /* Function prototypes */
49 static int cyberjack_port_probe(struct usb_serial_port *port);
50 static int cyberjack_port_remove(struct usb_serial_port *port);
51 static int  cyberjack_open(struct tty_struct *tty,
52 	struct usb_serial_port *port);
53 static void cyberjack_close(struct usb_serial_port *port);
54 static int cyberjack_write(struct tty_struct *tty,
55 	struct usb_serial_port *port, const unsigned char *buf, int count);
56 static int cyberjack_write_room(struct tty_struct *tty);
57 static void cyberjack_read_int_callback(struct urb *urb);
58 static void cyberjack_read_bulk_callback(struct urb *urb);
59 static void cyberjack_write_bulk_callback(struct urb *urb);
60 
61 static const struct usb_device_id id_table[] = {
62 	{ USB_DEVICE(CYBERJACK_VENDOR_ID, CYBERJACK_PRODUCT_ID) },
63 	{ }			/* Terminating entry */
64 };
65 
66 MODULE_DEVICE_TABLE(usb, id_table);
67 
68 static struct usb_serial_driver cyberjack_device = {
69 	.driver = {
70 		.owner =	THIS_MODULE,
71 		.name =		"cyberjack",
72 	},
73 	.description =		"Reiner SCT Cyberjack USB card reader",
74 	.id_table =		id_table,
75 	.num_ports =		1,
76 	.num_bulk_out =		1,
77 	.port_probe =		cyberjack_port_probe,
78 	.port_remove =		cyberjack_port_remove,
79 	.open =			cyberjack_open,
80 	.close =		cyberjack_close,
81 	.write =		cyberjack_write,
82 	.write_room =		cyberjack_write_room,
83 	.read_int_callback =	cyberjack_read_int_callback,
84 	.read_bulk_callback =	cyberjack_read_bulk_callback,
85 	.write_bulk_callback =	cyberjack_write_bulk_callback,
86 };
87 
88 static struct usb_serial_driver * const serial_drivers[] = {
89 	&cyberjack_device, NULL
90 };
91 
92 struct cyberjack_private {
93 	spinlock_t	lock;		/* Lock for SMP */
94 	short		rdtodo;		/* Bytes still to read */
95 	unsigned char	wrbuf[5*64];	/* Buffer for collecting data to write */
96 	short		wrfilled;	/* Overall data size we already got */
97 	short		wrsent;		/* Data already sent */
98 };
99 
100 static int cyberjack_port_probe(struct usb_serial_port *port)
101 {
102 	struct cyberjack_private *priv;
103 	int result;
104 
105 	priv = kmalloc(sizeof(struct cyberjack_private), GFP_KERNEL);
106 	if (!priv)
107 		return -ENOMEM;
108 
109 	spin_lock_init(&priv->lock);
110 	priv->rdtodo = 0;
111 	priv->wrfilled = 0;
112 	priv->wrsent = 0;
113 
114 	usb_set_serial_port_data(port, priv);
115 
116 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
117 	if (result)
118 		dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
119 
120 	return 0;
121 }
122 
123 static int cyberjack_port_remove(struct usb_serial_port *port)
124 {
125 	struct cyberjack_private *priv;
126 
127 	usb_kill_urb(port->interrupt_in_urb);
128 
129 	priv = usb_get_serial_port_data(port);
130 	kfree(priv);
131 
132 	return 0;
133 }
134 
135 static int  cyberjack_open(struct tty_struct *tty,
136 					struct usb_serial_port *port)
137 {
138 	struct cyberjack_private *priv;
139 	unsigned long flags;
140 
141 	dev_dbg(&port->dev, "%s - usb_clear_halt\n", __func__);
142 	usb_clear_halt(port->serial->dev, port->write_urb->pipe);
143 
144 	priv = usb_get_serial_port_data(port);
145 	spin_lock_irqsave(&priv->lock, flags);
146 	priv->rdtodo = 0;
147 	priv->wrfilled = 0;
148 	priv->wrsent = 0;
149 	spin_unlock_irqrestore(&priv->lock, flags);
150 
151 	return 0;
152 }
153 
154 static void cyberjack_close(struct usb_serial_port *port)
155 {
156 	usb_kill_urb(port->write_urb);
157 	usb_kill_urb(port->read_urb);
158 }
159 
160 static int cyberjack_write(struct tty_struct *tty,
161 	struct usb_serial_port *port, const unsigned char *buf, int count)
162 {
163 	struct device *dev = &port->dev;
164 	struct cyberjack_private *priv = usb_get_serial_port_data(port);
165 	unsigned long flags;
166 	int result;
167 	int wrexpected;
168 
169 	if (count == 0) {
170 		dev_dbg(dev, "%s - write request of 0 bytes\n", __func__);
171 		return 0;
172 	}
173 
174 	if (!test_and_clear_bit(0, &port->write_urbs_free)) {
175 		dev_dbg(dev, "%s - already writing\n", __func__);
176 		return 0;
177 	}
178 
179 	spin_lock_irqsave(&priv->lock, flags);
180 
181 	if (count+priv->wrfilled > sizeof(priv->wrbuf)) {
182 		/* To much data for buffer. Reset buffer. */
183 		priv->wrfilled = 0;
184 		spin_unlock_irqrestore(&priv->lock, flags);
185 		set_bit(0, &port->write_urbs_free);
186 		return 0;
187 	}
188 
189 	/* Copy data */
190 	memcpy(priv->wrbuf + priv->wrfilled, buf, count);
191 
192 	usb_serial_debug_data(dev, __func__, count, priv->wrbuf + priv->wrfilled);
193 	priv->wrfilled += count;
194 
195 	if (priv->wrfilled >= 3) {
196 		wrexpected = ((int)priv->wrbuf[2]<<8)+priv->wrbuf[1]+3;
197 		dev_dbg(dev, "%s - expected data: %d\n", __func__, wrexpected);
198 	} else
199 		wrexpected = sizeof(priv->wrbuf);
200 
201 	if (priv->wrfilled >= wrexpected) {
202 		/* We have enough data to begin transmission */
203 		int length;
204 
205 		dev_dbg(dev, "%s - transmitting data (frame 1)\n", __func__);
206 		length = (wrexpected > port->bulk_out_size) ?
207 					port->bulk_out_size : wrexpected;
208 
209 		memcpy(port->write_urb->transfer_buffer, priv->wrbuf, length);
210 		priv->wrsent = length;
211 
212 		/* set up our urb */
213 		port->write_urb->transfer_buffer_length = length;
214 
215 		/* send the data out the bulk port */
216 		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
217 		if (result) {
218 			dev_err(&port->dev,
219 				"%s - failed submitting write urb, error %d\n",
220 				__func__, result);
221 			/* Throw away data. No better idea what to do with it. */
222 			priv->wrfilled = 0;
223 			priv->wrsent = 0;
224 			spin_unlock_irqrestore(&priv->lock, flags);
225 			set_bit(0, &port->write_urbs_free);
226 			return 0;
227 		}
228 
229 		dev_dbg(dev, "%s - priv->wrsent=%d\n", __func__, priv->wrsent);
230 		dev_dbg(dev, "%s - priv->wrfilled=%d\n", __func__, priv->wrfilled);
231 
232 		if (priv->wrsent >= priv->wrfilled) {
233 			dev_dbg(dev, "%s - buffer cleaned\n", __func__);
234 			memset(priv->wrbuf, 0, sizeof(priv->wrbuf));
235 			priv->wrfilled = 0;
236 			priv->wrsent = 0;
237 		}
238 	}
239 
240 	spin_unlock_irqrestore(&priv->lock, flags);
241 
242 	return count;
243 }
244 
245 static int cyberjack_write_room(struct tty_struct *tty)
246 {
247 	/* FIXME: .... */
248 	return CYBERJACK_LOCAL_BUF_SIZE;
249 }
250 
251 static void cyberjack_read_int_callback(struct urb *urb)
252 {
253 	struct usb_serial_port *port = urb->context;
254 	struct cyberjack_private *priv = usb_get_serial_port_data(port);
255 	struct device *dev = &port->dev;
256 	unsigned char *data = urb->transfer_buffer;
257 	int status = urb->status;
258 	unsigned long flags;
259 	int result;
260 
261 	/* the urb might have been killed. */
262 	if (status)
263 		return;
264 
265 	usb_serial_debug_data(dev, __func__, urb->actual_length, data);
266 
267 	/* React only to interrupts signaling a bulk_in transfer */
268 	if (urb->actual_length == 4 && data[0] == 0x01) {
269 		short old_rdtodo;
270 
271 		/* This is a announcement of coming bulk_ins. */
272 		unsigned short size = ((unsigned short)data[3]<<8)+data[2]+3;
273 
274 		spin_lock_irqsave(&priv->lock, flags);
275 
276 		old_rdtodo = priv->rdtodo;
277 
278 		if (old_rdtodo > SHRT_MAX - size) {
279 			dev_dbg(dev, "To many bulk_in urbs to do.\n");
280 			spin_unlock_irqrestore(&priv->lock, flags);
281 			goto resubmit;
282 		}
283 
284 		/* "+=" is probably more fault tolerant than "=" */
285 		priv->rdtodo += size;
286 
287 		dev_dbg(dev, "%s - rdtodo: %d\n", __func__, priv->rdtodo);
288 
289 		spin_unlock_irqrestore(&priv->lock, flags);
290 
291 		if (!old_rdtodo) {
292 			result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
293 			if (result)
294 				dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
295 					__func__, result);
296 			dev_dbg(dev, "%s - usb_submit_urb(read urb)\n", __func__);
297 		}
298 	}
299 
300 resubmit:
301 	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
302 	if (result)
303 		dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
304 	dev_dbg(dev, "%s - usb_submit_urb(int urb)\n", __func__);
305 }
306 
307 static void cyberjack_read_bulk_callback(struct urb *urb)
308 {
309 	struct usb_serial_port *port = urb->context;
310 	struct cyberjack_private *priv = usb_get_serial_port_data(port);
311 	struct device *dev = &port->dev;
312 	unsigned char *data = urb->transfer_buffer;
313 	unsigned long flags;
314 	short todo;
315 	int result;
316 	int status = urb->status;
317 
318 	usb_serial_debug_data(dev, __func__, urb->actual_length, data);
319 	if (status) {
320 		dev_dbg(dev, "%s - nonzero read bulk status received: %d\n",
321 			__func__, status);
322 		return;
323 	}
324 
325 	if (urb->actual_length) {
326 		tty_insert_flip_string(&port->port, data, urb->actual_length);
327 		tty_flip_buffer_push(&port->port);
328 	}
329 
330 	spin_lock_irqsave(&priv->lock, flags);
331 
332 	/* Reduce urbs to do by one. */
333 	priv->rdtodo -= urb->actual_length;
334 	/* Just to be sure */
335 	if (priv->rdtodo < 0)
336 		priv->rdtodo = 0;
337 	todo = priv->rdtodo;
338 
339 	spin_unlock_irqrestore(&priv->lock, flags);
340 
341 	dev_dbg(dev, "%s - rdtodo: %d\n", __func__, todo);
342 
343 	/* Continue to read if we have still urbs to do. */
344 	if (todo /* || (urb->actual_length==port->bulk_in_endpointAddress)*/) {
345 		result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
346 		if (result)
347 			dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
348 				__func__, result);
349 		dev_dbg(dev, "%s - usb_submit_urb(read urb)\n", __func__);
350 	}
351 }
352 
353 static void cyberjack_write_bulk_callback(struct urb *urb)
354 {
355 	struct usb_serial_port *port = urb->context;
356 	struct cyberjack_private *priv = usb_get_serial_port_data(port);
357 	struct device *dev = &port->dev;
358 	int status = urb->status;
359 	unsigned long flags;
360 
361 	set_bit(0, &port->write_urbs_free);
362 	if (status) {
363 		dev_dbg(dev, "%s - nonzero write bulk status received: %d\n",
364 			__func__, status);
365 		return;
366 	}
367 
368 	spin_lock_irqsave(&priv->lock, flags);
369 
370 	/* only do something if we have more data to send */
371 	if (priv->wrfilled) {
372 		int length, blksize, result;
373 
374 		dev_dbg(dev, "%s - transmitting data (frame n)\n", __func__);
375 
376 		length = ((priv->wrfilled - priv->wrsent) > port->bulk_out_size) ?
377 			port->bulk_out_size : (priv->wrfilled - priv->wrsent);
378 
379 		memcpy(port->write_urb->transfer_buffer,
380 					priv->wrbuf + priv->wrsent, length);
381 		priv->wrsent += length;
382 
383 		/* set up our urb */
384 		port->write_urb->transfer_buffer_length = length;
385 
386 		/* send the data out the bulk port */
387 		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
388 		if (result) {
389 			dev_err(dev, "%s - failed submitting write urb, error %d\n",
390 				__func__, result);
391 			/* Throw away data. No better idea what to do with it. */
392 			priv->wrfilled = 0;
393 			priv->wrsent = 0;
394 			goto exit;
395 		}
396 
397 		dev_dbg(dev, "%s - priv->wrsent=%d\n", __func__, priv->wrsent);
398 		dev_dbg(dev, "%s - priv->wrfilled=%d\n", __func__, priv->wrfilled);
399 
400 		blksize = ((int)priv->wrbuf[2]<<8)+priv->wrbuf[1]+3;
401 
402 		if (priv->wrsent >= priv->wrfilled ||
403 					priv->wrsent >= blksize) {
404 			dev_dbg(dev, "%s - buffer cleaned\n", __func__);
405 			memset(priv->wrbuf, 0, sizeof(priv->wrbuf));
406 			priv->wrfilled = 0;
407 			priv->wrsent = 0;
408 		}
409 	}
410 
411 exit:
412 	spin_unlock_irqrestore(&priv->lock, flags);
413 	usb_serial_port_softint(port);
414 }
415 
416 module_usb_serial_driver(serial_drivers, id_table);
417 
418 MODULE_AUTHOR(DRIVER_AUTHOR);
419 MODULE_DESCRIPTION(DRIVER_DESC);
420 MODULE_LICENSE("GPL");
421