USB: rename usb_buffer_alloc() and usb_buffer_free() users
[linux-2.6.git] / drivers / usb / misc / usblcd.c
1 /*****************************************************************************
2  *                          USBLCD Kernel Driver                             *
3  *                            Version 1.05                                   *
4  *             (C) 2005 Georges Toth <g.toth@e-biz.lu>                       *
5  *                                                                           *
6  *     This file is licensed under the GPL. See COPYING in the package.      *
7  * Based on usb-skeleton.c 2.0 by Greg Kroah-Hartman (greg@kroah.com)        *
8  *                                                                           *
9  *                                                                           *
10  * 28.02.05 Complete rewrite of the original usblcd.c driver,                *
11  *          based on usb_skeleton.c.                                         *
12  *          This new driver allows more than one USB-LCD to be connected     *
13  *          and controlled, at once                                          *
14  *****************************************************************************/
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
33 static const struct usb_device_id id_table[] = {
34         { .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },
35         { },
36 };
37 MODULE_DEVICE_TABLE (usb, id_table);
38
39 static DEFINE_MUTEX(open_disc_mutex);
40
41
42 struct usb_lcd {
43         struct usb_device *     udev;                   /* init: probe_lcd */
44         struct usb_interface *  interface;              /* the interface for this device */
45         unsigned char *         bulk_in_buffer;         /* the buffer to receive data */
46         size_t                  bulk_in_size;           /* the size of the receive buffer */
47         __u8                    bulk_in_endpointAddr;   /* the address of the bulk in endpoint */
48         __u8                    bulk_out_endpointAddr;  /* the address of the bulk out endpoint */
49         struct kref             kref;
50         struct semaphore        limit_sem;              /* to stop writes at full throttle from
51                                                          * using up all RAM */
52         struct usb_anchor       submitted;              /* URBs to wait for before suspend */
53 };
54 #define to_lcd_dev(d) container_of(d, struct usb_lcd, kref)
55
56 #define USB_LCD_CONCURRENT_WRITES       5
57
58 static struct usb_driver lcd_driver;
59
60
61 static 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
71 static 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         lock_kernel();
78         subminor = iminor(inode);
79
80         interface = usb_find_interface(&lcd_driver, subminor);
81         if (!interface) {
82                 unlock_kernel();
83                 err ("USBLCD: %s - error, can't find device for minor %d",
84                      __func__, subminor);
85                 return -ENODEV;
86         }
87
88         mutex_lock(&open_disc_mutex);
89         dev = usb_get_intfdata(interface);
90         if (!dev) {
91                 mutex_unlock(&open_disc_mutex);
92                 unlock_kernel();
93                 return -ENODEV;
94         }
95
96         /* increment our usage count for the device */
97         kref_get(&dev->kref);
98         mutex_unlock(&open_disc_mutex);
99
100         /* grab a power reference */
101         r = usb_autopm_get_interface(interface);
102         if (r < 0) {
103                 kref_put(&dev->kref, lcd_delete);
104                 unlock_kernel();
105                 return r;
106         }
107
108         /* save our object in the file's private structure */
109         file->private_data = dev;
110         unlock_kernel();
111
112         return 0;
113 }
114
115 static int lcd_release(struct inode *inode, struct file *file)
116 {
117         struct usb_lcd *dev;
118
119         dev = (struct usb_lcd *)file->private_data;
120         if (dev == NULL)
121                 return -ENODEV;
122
123         /* decrement the count on our device */
124         usb_autopm_put_interface(dev->interface);
125         kref_put(&dev->kref, lcd_delete);
126         return 0;
127 }
128
129 static ssize_t lcd_read(struct file *file, char __user * buffer, size_t count, loff_t *ppos)
130 {
131         struct usb_lcd *dev;
132         int retval = 0;
133         int bytes_read;
134
135         dev = (struct usb_lcd *)file->private_data;
136
137         /* do a blocking bulk read to get data from the device */
138         retval = usb_bulk_msg(dev->udev, 
139                               usb_rcvbulkpipe(dev->udev, dev->bulk_in_endpointAddr),
140                               dev->bulk_in_buffer,
141                               min(dev->bulk_in_size, count),
142                               &bytes_read, 10000);
143
144         /* if the read was successful, copy the data to userspace */
145         if (!retval) {
146                 if (copy_to_user(buffer, dev->bulk_in_buffer, bytes_read))
147                         retval = -EFAULT;
148                 else
149                         retval = bytes_read;
150         }
151
152         return retval;
153 }
154
155 static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
156 {
157         struct usb_lcd *dev;
158         u16 bcdDevice;
159         char buf[30];
160
161         dev = (struct usb_lcd *)file->private_data;
162         if (dev == NULL)
163                 return -ENODEV;
164         
165         switch (cmd) {
166         case IOCTL_GET_HARD_VERSION:
167                 lock_kernel();
168                 bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice);
169                 sprintf(buf,"%1d%1d.%1d%1d",
170                         (bcdDevice & 0xF000)>>12,
171                         (bcdDevice & 0xF00)>>8,
172                         (bcdDevice & 0xF0)>>4,
173                         (bcdDevice & 0xF));
174                 unlock_kernel();
175                 if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
176                         return -EFAULT;
177                 break;
178         case IOCTL_GET_DRV_VERSION:
179                 sprintf(buf,DRIVER_VERSION);
180                 if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
181                         return -EFAULT;
182                 break;
183         default:
184                 return -ENOTTY;
185                 break;
186         }
187
188         return 0;
189 }
190
191 static void lcd_write_bulk_callback(struct urb *urb)
192 {
193         struct usb_lcd *dev;
194         int status = urb->status;
195
196         dev = urb->context;
197
198         /* sync/async unlink faults aren't errors */
199         if (status &&
200             !(status == -ENOENT ||
201               status == -ECONNRESET ||
202               status == -ESHUTDOWN)) {
203                 dbg("USBLCD: %s - nonzero write bulk status received: %d",
204                     __func__, status);
205         }
206
207         /* free up our allocated buffer */
208         usb_free_coherent(urb->dev, urb->transfer_buffer_length,
209                           urb->transfer_buffer, urb->transfer_dma);
210         up(&dev->limit_sem);
211 }
212
213 static ssize_t lcd_write(struct file *file, const char __user * user_buffer, size_t count, loff_t *ppos)
214 {
215         struct usb_lcd *dev;
216         int retval = 0, r;
217         struct urb *urb = NULL;
218         char *buf = NULL;
219         
220         dev = (struct usb_lcd *)file->private_data;
221         
222         /* verify that we actually have some data to write */
223         if (count == 0)
224                 goto exit;
225
226         r = down_interruptible(&dev->limit_sem);
227         if (r < 0)
228                 return -EINTR;
229
230         /* create a urb, and a buffer for it, and copy the data to the urb */
231         urb = usb_alloc_urb(0, GFP_KERNEL);
232         if (!urb) {
233                 retval = -ENOMEM;
234                 goto err_no_buf;
235         }
236         
237         buf = usb_alloc_coherent(dev->udev, count, GFP_KERNEL, &urb->transfer_dma);
238         if (!buf) {
239                 retval = -ENOMEM;
240                 goto error;
241         }
242         
243         if (copy_from_user(buf, user_buffer, count)) {
244                 retval = -EFAULT;
245                 goto error;
246         }
247         
248         /* initialize the urb properly */
249         usb_fill_bulk_urb(urb, dev->udev,
250                           usb_sndbulkpipe(dev->udev, dev->bulk_out_endpointAddr),
251                           buf, count, lcd_write_bulk_callback, dev);
252         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
253
254         usb_anchor_urb(urb, &dev->submitted);
255         
256         /* send the data out the bulk port */
257         retval = usb_submit_urb(urb, GFP_KERNEL);
258         if (retval) {
259                 err("USBLCD: %s - failed submitting write urb, error %d", __func__, retval);
260                 goto error_unanchor;
261         }
262         
263         /* release our reference to this urb, the USB core will eventually free it entirely */
264         usb_free_urb(urb);
265
266 exit:
267         return count;
268 error_unanchor:
269         usb_unanchor_urb(urb);
270 error:
271         usb_free_coherent(dev->udev, count, buf, urb->transfer_dma);
272         usb_free_urb(urb);
273 err_no_buf:
274         up(&dev->limit_sem);
275         return retval;
276 }
277
278 static const struct file_operations lcd_fops = {
279         .owner =        THIS_MODULE,
280         .read =         lcd_read,
281         .write =        lcd_write,
282         .open =         lcd_open,
283         .unlocked_ioctl = lcd_ioctl,
284         .release =      lcd_release,
285 };
286
287 /*
288  * usb class driver info in order to get a minor number from the usb core,
289  * and to have the device registered with the driver core
290  */
291 static struct usb_class_driver lcd_class = {
292         .name =         "lcd%d",
293         .fops =         &lcd_fops,
294         .minor_base =   USBLCD_MINOR,
295 };
296
297 static int lcd_probe(struct usb_interface *interface, const struct usb_device_id *id)
298 {
299         struct usb_lcd *dev = NULL;
300         struct usb_host_interface *iface_desc;
301         struct usb_endpoint_descriptor *endpoint;
302         size_t buffer_size;
303         int i;
304         int retval = -ENOMEM;
305
306         /* allocate memory for our device state and initialize it */
307         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
308         if (dev == NULL) {
309                 err("Out of memory");
310                 goto error;
311         }
312         kref_init(&dev->kref);
313         sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES);
314         init_usb_anchor(&dev->submitted);
315
316         dev->udev = usb_get_dev(interface_to_usbdev(interface));
317         dev->interface = interface;
318
319         if (le16_to_cpu(dev->udev->descriptor.idProduct) != 0x0001) {
320                 dev_warn(&interface->dev, "USBLCD model not supported.\n");
321                 retval = -ENODEV;
322                 goto error;
323         }
324         
325         /* set up the endpoint information */
326         /* use only the first bulk-in and bulk-out endpoints */
327         iface_desc = interface->cur_altsetting;
328         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
329                 endpoint = &iface_desc->endpoint[i].desc;
330
331                 if (!dev->bulk_in_endpointAddr &&
332                     usb_endpoint_is_bulk_in(endpoint)) {
333                         /* we found a bulk in endpoint */
334                         buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
335                         dev->bulk_in_size = buffer_size;
336                         dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
337                         dev->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
338                         if (!dev->bulk_in_buffer) {
339                                 err("Could not allocate bulk_in_buffer");
340                                 goto error;
341                         }
342                 }
343
344                 if (!dev->bulk_out_endpointAddr &&
345                     usb_endpoint_is_bulk_out(endpoint)) {
346                         /* we found a bulk out endpoint */
347                         dev->bulk_out_endpointAddr = endpoint->bEndpointAddress;
348                 }
349         }
350         if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) {
351                 err("Could not find both bulk-in and bulk-out endpoints");
352                 goto error;
353         }
354
355         /* save our data pointer in this interface device */
356         usb_set_intfdata(interface, dev);
357
358         /* we can register the device now, as it is ready */
359         retval = usb_register_dev(interface, &lcd_class);
360         if (retval) {
361                 /* something prevented us from registering this driver */
362                 err("Not able to get a minor for this device.");
363                 usb_set_intfdata(interface, NULL);
364                 goto error;
365         }
366
367         i = le16_to_cpu(dev->udev->descriptor.bcdDevice);
368
369         dev_info(&interface->dev, "USBLCD Version %1d%1d.%1d%1d found "
370                  "at address %d\n", (i & 0xF000)>>12, (i & 0xF00)>>8,
371                  (i & 0xF0)>>4,(i & 0xF), dev->udev->devnum);
372
373         /* let the user know what node this device is now attached to */
374         dev_info(&interface->dev, "USB LCD device now attached to USBLCD-%d\n",
375                  interface->minor);
376         return 0;
377
378 error:
379         if (dev)
380                 kref_put(&dev->kref, lcd_delete);
381         return retval;
382 }
383
384 static void lcd_draw_down(struct usb_lcd *dev)
385 {
386         int time;
387
388         time = usb_wait_anchor_empty_timeout(&dev->submitted, 1000);
389         if (!time)
390                 usb_kill_anchored_urbs(&dev->submitted);
391 }
392
393 static int lcd_suspend(struct usb_interface *intf, pm_message_t message)
394 {
395         struct usb_lcd *dev = usb_get_intfdata(intf);
396
397         if (!dev)
398                 return 0;
399         lcd_draw_down(dev);
400         return 0;
401 }
402
403 static int lcd_resume (struct usb_interface *intf)
404 {
405         return 0;
406 }
407
408 static void lcd_disconnect(struct usb_interface *interface)
409 {
410         struct usb_lcd *dev;
411         int minor = interface->minor;
412
413         mutex_lock(&open_disc_mutex);
414         dev = usb_get_intfdata(interface);
415         usb_set_intfdata(interface, NULL);
416         mutex_unlock(&open_disc_mutex);
417
418         /* give back our minor */
419         usb_deregister_dev(interface, &lcd_class);
420  
421         /* decrement our usage count */
422         kref_put(&dev->kref, lcd_delete);
423
424         dev_info(&interface->dev, "USB LCD #%d now disconnected\n", minor);
425 }
426
427 static struct usb_driver lcd_driver = {
428         .name =         "usblcd",
429         .probe =        lcd_probe,
430         .disconnect =   lcd_disconnect,
431         .suspend =      lcd_suspend,
432         .resume =       lcd_resume,
433         .id_table =     id_table,
434         .supports_autosuspend = 1,
435 };
436
437 static int __init usb_lcd_init(void)
438 {
439         int result;
440         
441         result = usb_register(&lcd_driver);
442         if (result)
443                 err("usb_register failed. Error number %d", result);
444
445         return result;
446 }
447
448
449 static void __exit usb_lcd_exit(void)
450 {
451         usb_deregister(&lcd_driver);
452 }
453
454 module_init(usb_lcd_init);
455 module_exit(usb_lcd_exit);
456
457 MODULE_AUTHOR("Georges Toth <g.toth@e-biz.lu>");
458 MODULE_DESCRIPTION(DRIVER_VERSION);
459 MODULE_LICENSE("GPL");