1
2
3
4
5
6
7
8
9
10
11
12
13
14
15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/slab.h>
18#include <linux/errno.h>
19#include <linux/mutex.h>
20#include <linux/uaccess.h>
21#include <linux/usb.h>
22
23#define DRIVER_VERSION "USBLCD Driver Version 1.05"
24
25#define USBLCD_MINOR 144
26
27#define IOCTL_GET_HARD_VERSION 1
28#define IOCTL_GET_DRV_VERSION 2
29
30
31static DEFINE_MUTEX(lcd_mutex);
32static const struct usb_device_id id_table[] = {
33 { .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },
34 { },
35};
36MODULE_DEVICE_TABLE(usb, id_table);
37
38static DEFINE_MUTEX(open_disc_mutex);
39
40
41struct usb_lcd {
42 struct usb_device *udev;
43 struct usb_interface *interface;
44
45 unsigned char *bulk_in_buffer;
46
47 size_t bulk_in_size;
48
49 __u8 bulk_in_endpointAddr;
50
51 __u8 bulk_out_endpointAddr;
52
53 struct kref kref;
54 struct semaphore limit_sem;
55
56
57 struct usb_anchor submitted;
58
59};
60#define to_lcd_dev(d) container_of(d, struct usb_lcd, kref)
61
62#define USB_LCD_CONCURRENT_WRITES 5
63
64static struct usb_driver lcd_driver;
65
66
67static void lcd_delete(struct kref *kref)
68{
69 struct usb_lcd *dev = to_lcd_dev(kref);
70
71 usb_put_dev(dev->udev);
72 kfree(dev->bulk_in_buffer);
73 kfree(dev);
74}
75
76
77static int lcd_open(struct inode *inode, struct file *file)
78{
79 struct usb_lcd *dev;
80 struct usb_interface *interface;
81 int subminor, r;
82
83 mutex_lock(&lcd_mutex);
84 subminor = iminor(inode);
85
86 interface = usb_find_interface(&lcd_driver, subminor);
87 if (!interface) {
88 mutex_unlock(&lcd_mutex);
89 printk(KERN_ERR "USBLCD: %s - error, can't find device for minor %d\n",
90 __func__, subminor);
91 return -ENODEV;
92 }
93
94 mutex_lock(&open_disc_mutex);
95 dev = usb_get_intfdata(interface);
96 if (!dev) {
97 mutex_unlock(&open_disc_mutex);
98 mutex_unlock(&lcd_mutex);
99 return -ENODEV;
100 }
101
102
103 kref_get(&dev->kref);
104 mutex_unlock(&open_disc_mutex);
105
106
107 r = usb_autopm_get_interface(interface);
108 if (r < 0) {
109 kref_put(&dev->kref, lcd_delete);
110 mutex_unlock(&lcd_mutex);
111 return r;
112 }
113
114
115 file->private_data = dev;
116 mutex_unlock(&lcd_mutex);
117
118 return 0;
119}
120
121static int lcd_release(struct inode *inode, struct file *file)
122{
123 struct usb_lcd *dev;
124
125 dev = file->private_data;
126 if (dev == NULL)
127 return -ENODEV;
128
129
130 usb_autopm_put_interface(dev->interface);
131 kref_put(&dev->kref, lcd_delete);
132 return 0;
133}
134
135static ssize_t lcd_read(struct file *file, char __user * buffer,
136 size_t count, loff_t *ppos)
137{
138 struct usb_lcd *dev;
139 int retval = 0;
140 int bytes_read;
141
142 dev = file->private_data;
143
144
145 retval = usb_bulk_msg(dev->udev,
146 usb_rcvbulkpipe(dev->udev,
147 dev->bulk_in_endpointAddr),
148 dev->bulk_in_buffer,
149 min(dev->bulk_in_size, count),
150 &bytes_read, 10000);
151
152
153 if (!retval) {
154 if (copy_to_user(buffer, dev->bulk_in_buffer, bytes_read))
155 retval = -EFAULT;
156 else
157 retval = bytes_read;
158 }
159
160 return retval;
161}
162
163static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
164{
165 struct usb_lcd *dev;
166 u16 bcdDevice;
167 char buf[30];
168
169 dev = file->private_data;
170 if (dev == NULL)
171 return -ENODEV;
172
173 switch (cmd) {
174 case IOCTL_GET_HARD_VERSION:
175 mutex_lock(&lcd_mutex);
176 bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice);
177 sprintf(buf, "%1d%1d.%1d%1d",
178 (bcdDevice & 0xF000)>>12,
179 (bcdDevice & 0xF00)>>8,
180 (bcdDevice & 0xF0)>>4,
181 (bcdDevice & 0xF));
182 mutex_unlock(&lcd_mutex);
183 if (copy_to_user((void __user *)arg, buf, strlen(buf)) != 0)
184 return -EFAULT;
185 break;
186 case IOCTL_GET_DRV_VERSION:
187 sprintf(buf, DRIVER_VERSION);
188 if (copy_to_user((void __user *)arg, buf, strlen(buf)) != 0)
189 return -EFAULT;
190 break;
191 default:
192 return -ENOTTY;
193 break;
194 }
195
196 return 0;
197}
198
199static void lcd_write_bulk_callback(struct urb *urb)
200{
201 struct usb_lcd *dev;
202 int status = urb->status;
203
204 dev = urb->context;
205
206
207 if (status &&
208 !(status == -ENOENT ||
209 status == -ECONNRESET ||
210 status == -ESHUTDOWN)) {
211 dev_dbg(&dev->interface->dev,
212 "nonzero write bulk status received: %d\n", status);
213 }
214
215
216 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
217 urb->transfer_buffer, urb->transfer_dma);
218 up(&dev->limit_sem);
219}
220
221static ssize_t lcd_write(struct file *file, const char __user * user_buffer,
222 size_t count, loff_t *ppos)
223{
224 struct usb_lcd *dev;
225 int retval = 0, r;
226 struct urb *urb = NULL;
227 char *buf = NULL;
228
229 dev = file->private_data;
230
231
232 if (count == 0)
233 goto exit;
234
235 r = down_interruptible(&dev->limit_sem);
236 if (r < 0)
237 return -EINTR;
238
239
240 urb = usb_alloc_urb(0, GFP_KERNEL);
241 if (!urb) {
242 retval = -ENOMEM;
243 goto err_no_buf;
244 }
245
246 buf = usb_alloc_coherent(dev->udev, count, GFP_KERNEL,
247 &urb->transfer_dma);
248 if (!buf) {
249 retval = -ENOMEM;
250 goto error;
251 }
252
253 if (copy_from_user(buf, user_buffer, count)) {
254 retval = -EFAULT;
255 goto error;
256 }
257
258
259 usb_fill_bulk_urb(urb, dev->udev,
260 usb_sndbulkpipe(dev->udev,
261 dev->bulk_out_endpointAddr),
262 buf, count, lcd_write_bulk_callback, dev);
263 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
264
265 usb_anchor_urb(urb, &dev->submitted);
266
267
268 retval = usb_submit_urb(urb, GFP_KERNEL);
269 if (retval) {
270 dev_err(&dev->udev->dev,
271 "%s - failed submitting write urb, error %d\n",
272 __func__, retval);
273 goto error_unanchor;
274 }
275
276
277
278 usb_free_urb(urb);
279
280exit:
281 return count;
282error_unanchor:
283 usb_unanchor_urb(urb);
284error:
285 usb_free_coherent(dev->udev, count, buf, urb->transfer_dma);
286 usb_free_urb(urb);
287err_no_buf:
288 up(&dev->limit_sem);
289 return retval;
290}
291
292static const struct file_operations lcd_fops = {
293 .owner = THIS_MODULE,
294 .read = lcd_read,
295 .write = lcd_write,
296 .open = lcd_open,
297 .unlocked_ioctl = lcd_ioctl,
298 .release = lcd_release,
299 .llseek = noop_llseek,
300};
301
302
303
304
305
306static struct usb_class_driver lcd_class = {
307 .name = "lcd%d",
308 .fops = &lcd_fops,
309 .minor_base = USBLCD_MINOR,
310};
311
312static int lcd_probe(struct usb_interface *interface,
313 const struct usb_device_id *id)
314{
315 struct usb_lcd *dev = NULL;
316 struct usb_host_interface *iface_desc;
317 struct usb_endpoint_descriptor *endpoint;
318 size_t buffer_size;
319 int i;
320 int retval = -ENOMEM;
321
322
323 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
324 if (dev == NULL) {
325 dev_err(&interface->dev, "Out of memory\n");
326 goto error;
327 }
328 kref_init(&dev->kref);
329 sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES);
330 init_usb_anchor(&dev->submitted);
331
332 dev->udev = usb_get_dev(interface_to_usbdev(interface));
333 dev->interface = interface;
334
335 if (le16_to_cpu(dev->udev->descriptor.idProduct) != 0x0001) {
336 dev_warn(&interface->dev, "USBLCD model not supported.\n");
337 retval = -ENODEV;
338 goto error;
339 }
340
341
342
343 iface_desc = interface->cur_altsetting;
344 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
345 endpoint = &iface_desc->endpoint[i].desc;
346
347 if (!dev->bulk_in_endpointAddr &&
348 usb_endpoint_is_bulk_in(endpoint)) {
349
350 buffer_size = usb_endpoint_maxp(endpoint);
351 dev->bulk_in_size = buffer_size;
352 dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
353 dev->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
354 if (!dev->bulk_in_buffer) {
355 dev_err(&interface->dev,
356 "Could not allocate bulk_in_buffer\n");
357 goto error;
358 }
359 }
360
361 if (!dev->bulk_out_endpointAddr &&
362 usb_endpoint_is_bulk_out(endpoint)) {
363
364 dev->bulk_out_endpointAddr = endpoint->bEndpointAddress;
365 }
366 }
367 if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) {
368 dev_err(&interface->dev,
369 "Could not find both bulk-in and bulk-out endpoints\n");
370 goto error;
371 }
372
373
374 usb_set_intfdata(interface, dev);
375
376
377 retval = usb_register_dev(interface, &lcd_class);
378 if (retval) {
379
380 dev_err(&interface->dev,
381 "Not able to get a minor for this device.\n");
382 usb_set_intfdata(interface, NULL);
383 goto error;
384 }
385
386 i = le16_to_cpu(dev->udev->descriptor.bcdDevice);
387
388 dev_info(&interface->dev, "USBLCD Version %1d%1d.%1d%1d found "
389 "at address %d\n", (i & 0xF000)>>12, (i & 0xF00)>>8,
390 (i & 0xF0)>>4, (i & 0xF), dev->udev->devnum);
391
392
393 dev_info(&interface->dev, "USB LCD device now attached to USBLCD-%d\n",
394 interface->minor);
395 return 0;
396
397error:
398 if (dev)
399 kref_put(&dev->kref, lcd_delete);
400 return retval;
401}
402
403static void lcd_draw_down(struct usb_lcd *dev)
404{
405 int time;
406
407 time = usb_wait_anchor_empty_timeout(&dev->submitted, 1000);
408 if (!time)
409 usb_kill_anchored_urbs(&dev->submitted);
410}
411
412static int lcd_suspend(struct usb_interface *intf, pm_message_t message)
413{
414 struct usb_lcd *dev = usb_get_intfdata(intf);
415
416 if (!dev)
417 return 0;
418 lcd_draw_down(dev);
419 return 0;
420}
421
422static int lcd_resume(struct usb_interface *intf)
423{
424 return 0;
425}
426
427static void lcd_disconnect(struct usb_interface *interface)
428{
429 struct usb_lcd *dev;
430 int minor = interface->minor;
431
432 mutex_lock(&open_disc_mutex);
433 dev = usb_get_intfdata(interface);
434 usb_set_intfdata(interface, NULL);
435 mutex_unlock(&open_disc_mutex);
436
437
438 usb_deregister_dev(interface, &lcd_class);
439
440
441 kref_put(&dev->kref, lcd_delete);
442
443 dev_info(&interface->dev, "USB LCD #%d now disconnected\n", minor);
444}
445
446static struct usb_driver lcd_driver = {
447 .name = "usblcd",
448 .probe = lcd_probe,
449 .disconnect = lcd_disconnect,
450 .suspend = lcd_suspend,
451 .resume = lcd_resume,
452 .id_table = id_table,
453 .supports_autosuspend = 1,
454};
455
456module_usb_driver(lcd_driver);
457
458MODULE_AUTHOR("Georges Toth <g.toth@e-biz.lu>");
459MODULE_DESCRIPTION(DRIVER_VERSION);
460MODULE_LICENSE("GPL");
461
