1 /*****************************************************************************
2 * USBLCD Kernel Driver *
3 * See http://www.usblcd.de for Hardware and Documentation. *
4 * Version 1.03 *
5 * (C) 2002 Adams IT Services <info@usblcd.de> *
6 * *
7 * This file is licensed under the GPL. See COPYING in the package. *
8 * Based on rio500.c by Cesar Miquel (miquel@df.uba.ar) which is based on *
9 * hp_scanner.c by David E. Nelson (dnelson@jump.net) *
10 * *
11 * 23.7.02 RA changed minor device number to the official assigned one *
12 * 18.9.02 RA Vendor ID change, longer timeouts *
13 *****************************************************************************/
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <linux/errno.h>
19 #include <asm/uaccess.h>
20 #include <linux/usb.h>
21
22 #define DRIVER_VERSION "USBLCD Driver Version 1.03"
23
24 #define USBLCD_MINOR 144
25
26 #define IOCTL_GET_HARD_VERSION 1
27 #define IOCTL_GET_DRV_VERSION 2
28
29 /* stall/wait timeout for USBLCD */
30 #define NAK_TIMEOUT (10*HZ)
31
32 #define IBUF_SIZE 0x1000
33 #define OBUF_SIZE 0x10000
34
35 struct lcd_usb_data {
36 struct usb_device *lcd_dev; /* init: probe_lcd */
37 unsigned int ifnum; /* Interface number of the USB device */
38 int isopen; /* nz if open */
39 int present; /* Device is present on the bus */
40 char *obuf, *ibuf; /* transfer buffers */
41 char bulk_in_ep, bulk_out_ep; /* Endpoint assignments */
42 wait_queue_head_t wait_q; /* for timeouts */
43 };
44
45 static struct lcd_usb_data lcd_instance;
46
open_lcd(struct inode * inode,struct file * file)47 static int open_lcd(struct inode *inode, struct file *file)
48 {
49 struct lcd_usb_data *lcd = &lcd_instance;
50
51 if (lcd->isopen || !lcd->present) {
52 return -EBUSY;
53 }
54 lcd->isopen = 1;
55
56 init_waitqueue_head(&lcd->wait_q);
57
58 info("USBLCD opened.");
59
60 return 0;
61 }
62
close_lcd(struct inode * inode,struct file * file)63 static int close_lcd(struct inode *inode, struct file *file)
64 {
65 struct lcd_usb_data *lcd = &lcd_instance;
66
67 lcd->isopen = 0;
68
69 info("USBLCD closed.");
70 return 0;
71 }
72
73 static int
ioctl_lcd(struct inode * inode,struct file * file,unsigned int cmd,unsigned long arg)74 ioctl_lcd(struct inode *inode, struct file *file, unsigned int cmd,
75 unsigned long arg)
76 {
77 struct lcd_usb_data *lcd = &lcd_instance;
78 int i;
79 char buf[30];
80
81 /* Sanity check to make sure lcd is connected, powered, etc */
82 if (lcd == NULL ||
83 lcd->present == 0 ||
84 lcd->lcd_dev == NULL)
85 return -1;
86
87 switch (cmd) {
88 case IOCTL_GET_HARD_VERSION:
89 i = (lcd->lcd_dev)->descriptor.bcdDevice;
90 sprintf(buf,"%1d%1d.%1d%1d",(i & 0xF000)>>12,(i & 0xF00)>>8,
91 (i & 0xF0)>>4,(i & 0xF));
92 if (copy_to_user((void *)arg,buf,strlen(buf))!=0)
93 return -EFAULT;
94 break;
95 case IOCTL_GET_DRV_VERSION:
96 sprintf(buf,DRIVER_VERSION);
97 if (copy_to_user((void *)arg,buf,strlen(buf))!=0)
98 return -EFAULT;
99 break;
100 default:
101 return -ENOIOCTLCMD;
102 break;
103 }
104
105 return 0;
106 }
107
108 static ssize_t
write_lcd(struct file * file,const char * buffer,size_t count,loff_t * ppos)109 write_lcd(struct file *file, const char *buffer,
110 size_t count, loff_t * ppos)
111 {
112 struct lcd_usb_data *lcd = &lcd_instance;
113
114 unsigned long copy_size;
115 unsigned long bytes_written = 0;
116 unsigned int partial;
117
118 int result = 0;
119 int maxretry;
120
121 /* Sanity check to make sure lcd is connected, powered, etc */
122 if (lcd == NULL ||
123 lcd->present == 0 ||
124 lcd->lcd_dev == NULL)
125 return -1;
126
127 do {
128 unsigned long thistime;
129 char *obuf = lcd->obuf;
130
131 thistime = copy_size =
132 (count >= OBUF_SIZE) ? OBUF_SIZE : count;
133 if (copy_from_user(lcd->obuf, buffer, copy_size))
134 return -EFAULT;
135 maxretry = 5;
136 while (thistime) {
137 if (!lcd->lcd_dev)
138 return -ENODEV;
139 if (signal_pending(current)) {
140 return bytes_written ? bytes_written : -EINTR;
141 }
142
143 result = usb_bulk_msg(lcd->lcd_dev,
144 usb_sndbulkpipe(lcd->lcd_dev, 1),
145 obuf, thistime, &partial, 10 * HZ);
146
147 dbg("write stats: result:%d thistime:%lu partial:%u",
148 result, thistime, partial);
149
150 if (result == USB_ST_TIMEOUT) { /* NAK - so hold for a while */
151 if (!maxretry--) {
152 return -ETIME;
153 }
154 interruptible_sleep_on_timeout(&lcd-> wait_q, NAK_TIMEOUT);
155 continue;
156 } else if (!result & partial) {
157 obuf += partial;
158 thistime -= partial;
159 } else
160 break;
161 };
162 if (result) {
163 err("Write Whoops - %x", result);
164 return -EIO;
165 }
166 bytes_written += copy_size;
167 count -= copy_size;
168 buffer += copy_size;
169 } while (count > 0);
170
171 return bytes_written ? bytes_written : -EIO;
172 }
173
174 static ssize_t
read_lcd(struct file * file,char * buffer,size_t count,loff_t * ppos)175 read_lcd(struct file *file, char *buffer, size_t count, loff_t * ppos)
176 {
177 struct lcd_usb_data *lcd = &lcd_instance;
178 ssize_t read_count;
179 unsigned int partial;
180 int this_read;
181 int result;
182 int maxretry = 10;
183 char *ibuf = lcd->ibuf;
184
185 /* Sanity check to make sure lcd is connected, powered, etc */
186 if (lcd == NULL ||
187 lcd->present == 0 ||
188 lcd->lcd_dev == NULL)
189 return -1;
190
191 read_count = 0;
192
193 while (count > 0) {
194 if (signal_pending(current)) {
195 return read_count ? read_count : -EINTR;
196 }
197 if (!lcd->lcd_dev)
198 return -ENODEV;
199 this_read = (count >= IBUF_SIZE) ? IBUF_SIZE : count;
200
201 result = usb_bulk_msg(lcd->lcd_dev,
202 usb_rcvbulkpipe(lcd->lcd_dev, 0),
203 ibuf, this_read, &partial,
204 (int) (HZ * 8));
205
206 dbg(KERN_DEBUG "read stats: result:%d this_read:%u partial:%u",
207 result, this_read, partial);
208
209 if (partial) {
210 count = this_read = partial;
211 } else if (result == USB_ST_TIMEOUT || result == 15) { /* FIXME: 15 ??? */
212 if (!maxretry--) {
213 err("read_lcd: maxretry timeout");
214 return -ETIME;
215 }
216 interruptible_sleep_on_timeout(&lcd->wait_q,
217 NAK_TIMEOUT);
218 continue;
219 } else if (result != USB_ST_DATAUNDERRUN) {
220 err("Read Whoops - result:%u partial:%u this_read:%u",
221 result, partial, this_read);
222 return -EIO;
223 } else {
224 return (0);
225 }
226
227 if (this_read) {
228 if (copy_to_user(buffer, ibuf, this_read))
229 return -EFAULT;
230 count -= this_read;
231 read_count += this_read;
232 buffer += this_read;
233 }
234 }
235 return read_count;
236 }
237
probe_lcd(struct usb_device * dev,unsigned int ifnum)238 static void *probe_lcd(struct usb_device *dev, unsigned int ifnum)
239 {
240 struct lcd_usb_data *lcd = &lcd_instance;
241 int i;
242
243 if (dev->descriptor.idProduct != 0x0001 ) {
244 warn(KERN_INFO "USBLCD model not supported.");
245 return NULL;
246 }
247
248 if (lcd->present == 1) {
249 warn(KERN_INFO "Multiple USBLCDs are not supported!");
250 return NULL;
251 }
252
253 i = dev->descriptor.bcdDevice;
254
255 info("USBLCD Version %1d%1d.%1d%1d found at address %d",
256 (i & 0xF000)>>12,(i & 0xF00)>>8,(i & 0xF0)>>4,(i & 0xF),
257 dev->devnum);
258
259 lcd->present = 1;
260 lcd->lcd_dev = dev;
261
262 if (!(lcd->obuf = (char *) kmalloc(OBUF_SIZE, GFP_KERNEL))) {
263 err("probe_lcd: Not enough memory for the output buffer");
264 return NULL;
265 }
266 dbg("probe_lcd: obuf address:%p", lcd->obuf);
267
268 if (!(lcd->ibuf = (char *) kmalloc(IBUF_SIZE, GFP_KERNEL))) {
269 err("probe_lcd: Not enough memory for the input buffer");
270 kfree(lcd->obuf);
271 return NULL;
272 }
273 dbg("probe_lcd: ibuf address:%p", lcd->ibuf);
274
275 return lcd;
276 }
277
disconnect_lcd(struct usb_device * dev,void * ptr)278 static void disconnect_lcd(struct usb_device *dev, void *ptr)
279 {
280 struct lcd_usb_data *lcd = (struct lcd_usb_data *) ptr;
281
282 if (lcd->isopen) {
283 lcd->isopen = 0;
284 /* better let it finish - the release will do whats needed */
285 lcd->lcd_dev = NULL;
286 return;
287 }
288 kfree(lcd->ibuf);
289 kfree(lcd->obuf);
290
291 info("USBLCD disconnected.");
292
293 lcd->present = 0;
294 }
295
296 static struct usb_device_id id_table [] = {
297 { .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },
298 {},
299 };
300
301 MODULE_DEVICE_TABLE (usb, id_table);
302
303 static struct
304 file_operations usb_lcd_fops = {
305 .owner = THIS_MODULE,
306 .read = read_lcd,
307 .write = write_lcd,
308 .ioctl = ioctl_lcd,
309 .open = open_lcd,
310 .release = close_lcd,
311 };
312
313 static struct
314 usb_driver lcd_driver = {
315 .name = "usblcd",
316 .probe = (void *)probe_lcd,
317 .disconnect = disconnect_lcd,
318 .id_table = id_table,
319 .fops = &usb_lcd_fops,
320 .minor = USBLCD_MINOR,
321 };
322
usb_lcd_init(void)323 int usb_lcd_init(void)
324 {
325 if (usb_register(&lcd_driver) < 0)
326 return -1;
327
328 info("%s (C) Adams IT Services http://www.usblcd.de", DRIVER_VERSION);
329 info("USBLCD support registered.");
330 return 0;
331 }
332
333
usb_lcd_cleanup(void)334 void usb_lcd_cleanup(void)
335 {
336 struct lcd_usb_data *lcd = &lcd_instance;
337
338 lcd->present = 0;
339 usb_deregister(&lcd_driver);
340 }
341
342 module_init(usb_lcd_init);
343 module_exit(usb_lcd_cleanup);
344
345 MODULE_AUTHOR("Adams IT Services <info@usblcd.de>");
346 MODULE_DESCRIPTION(DRIVER_VERSION);
347 MODULE_LICENSE("GPL");
348