xref: /openbmc/linux/drivers/usb/serial/cyberjack.c (revision 249592bf)
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 void 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 void 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 
133 static int  cyberjack_open(struct tty_struct *tty,
134 					struct usb_serial_port *port)
135 {
136 	struct cyberjack_private *priv;
137 	unsigned long flags;
138 
139 	dev_dbg(&port->dev, "%s - usb_clear_halt\n", __func__);
140 	usb_clear_halt(port->serial->dev, port->write_urb->pipe);
141 
142 	priv = usb_get_serial_port_data(port);
143 	spin_lock_irqsave(&priv->lock, flags);
144 	priv->rdtodo = 0;
145 	priv->wrfilled = 0;
146 	priv->wrsent = 0;
147 	spin_unlock_irqrestore(&priv->lock, flags);
148 
149 	return 0;
150 }
151 
152 static void cyberjack_close(struct usb_serial_port *port)
153 {
154 	usb_kill_urb(port->write_urb);
155 	usb_kill_urb(port->read_urb);
156 }
157 
158 static int cyberjack_write(struct tty_struct *tty,
159 	struct usb_serial_port *port, const unsigned char *buf, int count)
160 {
161 	struct device *dev = &port->dev;
162 	struct cyberjack_private *priv = usb_get_serial_port_data(port);
163 	unsigned long flags;
164 	int result;
165 	int wrexpected;
166 
167 	if (count == 0) {
168 		dev_dbg(dev, "%s - write request of 0 bytes\n", __func__);
169 		return 0;
170 	}
171 
172 	if (!test_and_clear_bit(0, &port->write_urbs_free)) {
173 		dev_dbg(dev, "%s - already writing\n", __func__);
174 		return 0;
175 	}
176 
177 	spin_lock_irqsave(&priv->lock, flags);
178 
179 	if (count+priv->wrfilled > sizeof(priv->wrbuf)) {
180 		/* To much data for buffer. Reset buffer. */
181 		priv->wrfilled = 0;
182 		spin_unlock_irqrestore(&priv->lock, flags);
183 		set_bit(0, &port->write_urbs_free);
184 		return 0;
185 	}
186 
187 	/* Copy data */
188 	memcpy(priv->wrbuf + priv->wrfilled, buf, count);
189 
190 	usb_serial_debug_data(dev, __func__, count, priv->wrbuf + priv->wrfilled);
191 	priv->wrfilled += count;
192 
193 	if (priv->wrfilled >= 3) {
194 		wrexpected = ((int)priv->wrbuf[2]<<8)+priv->wrbuf[1]+3;
195 		dev_dbg(dev, "%s - expected data: %d\n", __func__, wrexpected);
196 	} else
197 		wrexpected = sizeof(priv->wrbuf);
198 
199 	if (priv->wrfilled >= wrexpected) {
200 		/* We have enough data to begin transmission */
201 		int length;
202 
203 		dev_dbg(dev, "%s - transmitting data (frame 1)\n", __func__);
204 		length = (wrexpected > port->bulk_out_size) ?
205 					port->bulk_out_size : wrexpected;
206 
207 		memcpy(port->write_urb->transfer_buffer, priv->wrbuf, length);
208 		priv->wrsent = length;
209 
210 		/* set up our urb */
211 		port->write_urb->transfer_buffer_length = length;
212 
213 		/* send the data out the bulk port */
214 		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
215 		if (result) {
216 			dev_err(&port->dev,
217 				"%s - failed submitting write urb, error %d\n",
218 				__func__, result);
219 			/* Throw away data. No better idea what to do with it. */
220 			priv->wrfilled = 0;
221 			priv->wrsent = 0;
222 			spin_unlock_irqrestore(&priv->lock, flags);
223 			set_bit(0, &port->write_urbs_free);
224 			return 0;
225 		}
226 
227 		dev_dbg(dev, "%s - priv->wrsent=%d\n", __func__, priv->wrsent);
228 		dev_dbg(dev, "%s - priv->wrfilled=%d\n", __func__, priv->wrfilled);
229 
230 		if (priv->wrsent >= priv->wrfilled) {
231 			dev_dbg(dev, "%s - buffer cleaned\n", __func__);
232 			memset(priv->wrbuf, 0, sizeof(priv->wrbuf));
233 			priv->wrfilled = 0;
234 			priv->wrsent = 0;
235 		}
236 	}
237 
238 	spin_unlock_irqrestore(&priv->lock, flags);
239 
240 	return count;
241 }
242 
243 static int cyberjack_write_room(struct tty_struct *tty)
244 {
245 	/* FIXME: .... */
246 	return CYBERJACK_LOCAL_BUF_SIZE;
247 }
248 
249 static void cyberjack_read_int_callback(struct urb *urb)
250 {
251 	struct usb_serial_port *port = urb->context;
252 	struct cyberjack_private *priv = usb_get_serial_port_data(port);
253 	struct device *dev = &port->dev;
254 	unsigned char *data = urb->transfer_buffer;
255 	int status = urb->status;
256 	unsigned long flags;
257 	int result;
258 
259 	/* the urb might have been killed. */
260 	if (status)
261 		return;
262 
263 	usb_serial_debug_data(dev, __func__, urb->actual_length, data);
264 
265 	/* React only to interrupts signaling a bulk_in transfer */
266 	if (urb->actual_length == 4 && data[0] == 0x01) {
267 		short old_rdtodo;
268 
269 		/* This is a announcement of coming bulk_ins. */
270 		unsigned short size = ((unsigned short)data[3]<<8)+data[2]+3;
271 
272 		spin_lock_irqsave(&priv->lock, flags);
273 
274 		old_rdtodo = priv->rdtodo;
275 
276 		if (old_rdtodo > SHRT_MAX - size) {
277 			dev_dbg(dev, "Too many bulk_in urbs to do.\n");
278 			spin_unlock_irqrestore(&priv->lock, flags);
279 			goto resubmit;
280 		}
281 
282 		/* "+=" is probably more fault tolerant than "=" */
283 		priv->rdtodo += size;
284 
285 		dev_dbg(dev, "%s - rdtodo: %d\n", __func__, priv->rdtodo);
286 
287 		spin_unlock_irqrestore(&priv->lock, flags);
288 
289 		if (!old_rdtodo) {
290 			result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
291 			if (result)
292 				dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
293 					__func__, result);
294 			dev_dbg(dev, "%s - usb_submit_urb(read urb)\n", __func__);
295 		}
296 	}
297 
298 resubmit:
299 	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
300 	if (result)
301 		dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
302 	dev_dbg(dev, "%s - usb_submit_urb(int urb)\n", __func__);
303 }
304 
305 static void cyberjack_read_bulk_callback(struct urb *urb)
306 {
307 	struct usb_serial_port *port = urb->context;
308 	struct cyberjack_private *priv = usb_get_serial_port_data(port);
309 	struct device *dev = &port->dev;
310 	unsigned char *data = urb->transfer_buffer;
311 	unsigned long flags;
312 	short todo;
313 	int result;
314 	int status = urb->status;
315 
316 	usb_serial_debug_data(dev, __func__, urb->actual_length, data);
317 	if (status) {
318 		dev_dbg(dev, "%s - nonzero read bulk status received: %d\n",
319 			__func__, status);
320 		return;
321 	}
322 
323 	if (urb->actual_length) {
324 		tty_insert_flip_string(&port->port, data, urb->actual_length);
325 		tty_flip_buffer_push(&port->port);
326 	}
327 
328 	spin_lock_irqsave(&priv->lock, flags);
329 
330 	/* Reduce urbs to do by one. */
331 	priv->rdtodo -= urb->actual_length;
332 	/* Just to be sure */
333 	if (priv->rdtodo < 0)
334 		priv->rdtodo = 0;
335 	todo = priv->rdtodo;
336 
337 	spin_unlock_irqrestore(&priv->lock, flags);
338 
339 	dev_dbg(dev, "%s - rdtodo: %d\n", __func__, todo);
340 
341 	/* Continue to read if we have still urbs to do. */
342 	if (todo /* || (urb->actual_length==port->bulk_in_endpointAddress)*/) {
343 		result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
344 		if (result)
345 			dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
346 				__func__, result);
347 		dev_dbg(dev, "%s - usb_submit_urb(read urb)\n", __func__);
348 	}
349 }
350 
351 static void cyberjack_write_bulk_callback(struct urb *urb)
352 {
353 	struct usb_serial_port *port = urb->context;
354 	struct cyberjack_private *priv = usb_get_serial_port_data(port);
355 	struct device *dev = &port->dev;
356 	int status = urb->status;
357 	unsigned long flags;
358 	bool resubmitted = false;
359 
360 	if (status) {
361 		dev_dbg(dev, "%s - nonzero write bulk status received: %d\n",
362 			__func__, status);
363 		set_bit(0, &port->write_urbs_free);
364 		return;
365 	}
366 
367 	spin_lock_irqsave(&priv->lock, flags);
368 
369 	/* only do something if we have more data to send */
370 	if (priv->wrfilled) {
371 		int length, blksize, result;
372 
373 		dev_dbg(dev, "%s - transmitting data (frame n)\n", __func__);
374 
375 		length = ((priv->wrfilled - priv->wrsent) > port->bulk_out_size) ?
376 			port->bulk_out_size : (priv->wrfilled - priv->wrsent);
377 
378 		memcpy(port->write_urb->transfer_buffer,
379 					priv->wrbuf + priv->wrsent, length);
380 		priv->wrsent += length;
381 
382 		/* set up our urb */
383 		port->write_urb->transfer_buffer_length = length;
384 
385 		/* send the data out the bulk port */
386 		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
387 		if (result) {
388 			dev_err(dev, "%s - failed submitting write urb, error %d\n",
389 				__func__, result);
390 			/* Throw away data. No better idea what to do with it. */
391 			priv->wrfilled = 0;
392 			priv->wrsent = 0;
393 			goto exit;
394 		}
395 
396 		resubmitted = true;
397 
398 		dev_dbg(dev, "%s - priv->wrsent=%d\n", __func__, priv->wrsent);
399 		dev_dbg(dev, "%s - priv->wrfilled=%d\n", __func__, priv->wrfilled);
400 
401 		blksize = ((int)priv->wrbuf[2]<<8)+priv->wrbuf[1]+3;
402 
403 		if (priv->wrsent >= priv->wrfilled ||
404 					priv->wrsent >= blksize) {
405 			dev_dbg(dev, "%s - buffer cleaned\n", __func__);
406 			memset(priv->wrbuf, 0, sizeof(priv->wrbuf));
407 			priv->wrfilled = 0;
408 			priv->wrsent = 0;
409 		}
410 	}
411 
412 exit:
413 	spin_unlock_irqrestore(&priv->lock, flags);
414 	if (!resubmitted)
415 		set_bit(0, &port->write_urbs_free);
416 	usb_serial_port_softint(port);
417 }
418 
419 module_usb_serial_driver(serial_drivers, id_table);
420 
421 MODULE_AUTHOR(DRIVER_AUTHOR);
422 MODULE_DESCRIPTION(DRIVER_DESC);
423 MODULE_LICENSE("GPL");
424