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