bfde82f5d180a9b0e1f9fd460efed96940f5f195
[linux-3.10.git] / drivers / usb / misc / appledisplay.c
1 /*
2  * Apple Cinema Display driver
3  *
4  * Copyright (C) 2006  Michael Hanselmann (linux-kernel@hansmi.ch)
5  *
6  * Thanks to Caskey L. Dickson for his work with acdctl.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21  */
22
23 #include <linux/config.h>
24 #include <linux/kernel.h>
25 #include <linux/errno.h>
26 #include <linux/init.h>
27 #include <linux/module.h>
28 #include <linux/usb.h>
29 #include <linux/backlight.h>
30 #include <linux/timer.h>
31 #include <linux/workqueue.h>
32 #include <asm/atomic.h>
33 #include <asm/semaphore.h>
34
35 #define APPLE_VENDOR_ID         0x05AC
36
37 #define USB_REQ_GET_REPORT      0x01
38 #define USB_REQ_SET_REPORT      0x09
39
40 #define ACD_USB_TIMEOUT         250
41
42 #define ACD_USB_EDID            0x0302
43 #define ACD_USB_BRIGHTNESS      0x0310
44
45 #define ACD_BTN_NONE            0
46 #define ACD_BTN_BRIGHT_UP       3
47 #define ACD_BTN_BRIGHT_DOWN     4
48
49 #define ACD_URB_BUFFER_LEN      2
50 #define ACD_MSG_BUFFER_LEN      2
51
52 #define APPLEDISPLAY_DEVICE(prod)                               \
53         .match_flags = USB_DEVICE_ID_MATCH_DEVICE |             \
54                        USB_DEVICE_ID_MATCH_INT_CLASS |          \
55                        USB_DEVICE_ID_MATCH_INT_PROTOCOL,        \
56         .idVendor = APPLE_VENDOR_ID,                            \
57         .idProduct = (prod),                                    \
58         .bInterfaceClass = USB_CLASS_HID,                       \
59         .bInterfaceProtocol = 0x00
60
61 /* table of devices that work with this driver */
62 static struct usb_device_id appledisplay_table [] = {
63         { APPLEDISPLAY_DEVICE(0x9218) },
64         { APPLEDISPLAY_DEVICE(0x9219) },
65         { APPLEDISPLAY_DEVICE(0x921d) },
66
67         /* Terminating entry */
68         { }
69 };
70 MODULE_DEVICE_TABLE(usb, appledisplay_table);
71
72 /* Structure to hold all of our device specific stuff */
73 struct appledisplay {
74         struct usb_device *udev;        /* usb device */
75         struct urb *urb;                /* usb request block */
76         struct backlight_device *bd;    /* backlight device */
77         char *urbdata;                  /* interrupt URB data buffer */
78         char *msgdata;                  /* control message data buffer */
79
80         struct work_struct work;
81         int button_pressed;
82         spinlock_t lock;
83 };
84
85 static atomic_t count_displays = ATOMIC_INIT(0);
86 static struct workqueue_struct *wq;
87
88 static void appledisplay_complete(struct urb *urb, struct pt_regs *regs)
89 {
90         struct appledisplay *pdata = urb->context;
91         unsigned long flags;
92         int retval;
93
94         switch (urb->status) {
95         case 0:
96                 /* success */
97                 break;
98         case -EOVERFLOW:
99                 printk(KERN_ERR "appletouch: OVERFLOW with data "
100                         "length %d, actual length is %d\n",
101                         ACD_URB_BUFFER_LEN, pdata->urb->actual_length);
102         case -ECONNRESET:
103         case -ENOENT:
104         case -ESHUTDOWN:
105                 /* This urb is terminated, clean up */
106                 dbg("%s - urb shutting down with status: %d",
107                         __FUNCTION__, urb->status);
108                 return;
109         default:
110                 dbg("%s - nonzero urb status received: %d",
111                         __FUNCTION__, urb->status);
112                 goto exit;
113         }
114
115         spin_lock_irqsave(&pdata->lock, flags);
116
117         switch(pdata->urbdata[1]) {
118         case ACD_BTN_BRIGHT_UP:
119         case ACD_BTN_BRIGHT_DOWN:
120                 pdata->button_pressed = 1;
121                 queue_work(wq, &pdata->work);
122                 break;
123         case ACD_BTN_NONE:
124         default:
125                 pdata->button_pressed = 0;
126                 break;
127         }
128
129         spin_unlock_irqrestore(&pdata->lock, flags);
130
131 exit:
132         retval = usb_submit_urb(pdata->urb, GFP_ATOMIC);
133         if (retval) {
134                 err("%s - usb_submit_urb failed with result %d",
135                         __FUNCTION__, retval);
136         }
137 }
138
139 static int appledisplay_bl_update_status(struct backlight_device *bd)
140 {
141         struct appledisplay *pdata = class_get_devdata(&bd->class_dev);
142         int retval;
143
144         pdata->msgdata[0] = 0x10;
145         pdata->msgdata[1] = bd->props->brightness;
146
147         retval = usb_control_msg(
148                 pdata->udev,
149                 usb_sndctrlpipe(pdata->udev, 0),
150                 USB_REQ_SET_REPORT,
151                 USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
152                 ACD_USB_BRIGHTNESS,
153                 0,
154                 pdata->msgdata, 2,
155                 ACD_USB_TIMEOUT);
156
157         return retval;
158 }
159
160 static int appledisplay_bl_get_brightness(struct backlight_device *bd)
161 {
162         struct appledisplay *pdata = class_get_devdata(&bd->class_dev);
163         int retval;
164
165         retval = usb_control_msg(
166                 pdata->udev,
167                 usb_rcvctrlpipe(pdata->udev, 0),
168                 USB_REQ_GET_REPORT,
169                 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
170                 ACD_USB_BRIGHTNESS,
171                 0,
172                 pdata->msgdata, 2,
173                 ACD_USB_TIMEOUT);
174
175         if (retval < 0)
176                 return retval;
177         else
178                 return pdata->msgdata[1];
179 }
180
181 static struct backlight_properties appledisplay_bl_data = {
182         .owner          = THIS_MODULE,
183         .get_brightness = appledisplay_bl_get_brightness,
184         .update_status  = appledisplay_bl_update_status,
185         .max_brightness = 0xFF
186 };
187
188 static void appledisplay_work(void *private)
189 {
190         struct appledisplay *pdata = private;
191         int retval;
192
193         up(&pdata->bd->sem);
194         retval = appledisplay_bl_get_brightness(pdata->bd);
195         if (retval >= 0)
196                 pdata->bd->props->brightness = retval;
197         down(&pdata->bd->sem);
198
199         /* Poll again in about 125ms if there's still a button pressed */
200         if (pdata->button_pressed)
201                 schedule_delayed_work(&pdata->work, HZ / 8);
202 }
203
204 static int appledisplay_probe(struct usb_interface *iface,
205         const struct usb_device_id *id)
206 {
207         struct appledisplay *pdata;
208         struct usb_device *udev = interface_to_usbdev(iface);
209         struct usb_host_interface *iface_desc;
210         struct usb_endpoint_descriptor *endpoint;
211         int int_in_endpointAddr = 0;
212         int i, retval = -ENOMEM, brightness;
213         char bl_name[20];
214
215         /* set up the endpoint information */
216         /* use only the first interrupt-in endpoint */
217         iface_desc = iface->cur_altsetting;
218         for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
219                 endpoint = &iface_desc->endpoint[i].desc;
220                 if (!int_in_endpointAddr &&
221                     (endpoint->bEndpointAddress & USB_DIR_IN) &&
222                     ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
223                      USB_ENDPOINT_XFER_INT)) {
224                         /* we found an interrupt in endpoint */
225                         int_in_endpointAddr = endpoint->bEndpointAddress;
226                         break;
227                 }
228         }
229         if (!int_in_endpointAddr) {
230                 err("Could not find int-in endpoint");
231                 return -EIO;
232         }
233
234         /* allocate memory for our device state and initialize it */
235         pdata = kzalloc(sizeof(struct appledisplay), GFP_KERNEL);
236         if (!pdata) {
237                 retval = -ENOMEM;
238                 err("Out of memory");
239                 goto error;
240         }
241
242         pdata->udev = udev;
243
244         spin_lock_init(&pdata->lock);
245         INIT_WORK(&pdata->work, appledisplay_work, pdata);
246
247         /* Allocate buffer for control messages */
248         pdata->msgdata = kmalloc(ACD_MSG_BUFFER_LEN, GFP_KERNEL);
249         if (!pdata->msgdata) {
250                 retval = -ENOMEM;
251                 err("appledisplay: Allocating buffer for control messages "
252                         "failed");
253                 goto error;
254         }
255
256         /* Allocate interrupt URB */
257         pdata->urb = usb_alloc_urb(0, GFP_KERNEL);
258         if (!pdata->urb) {
259                 retval = -ENOMEM;
260                 err("appledisplay: Allocating URB failed");
261                 goto error;
262         }
263
264         /* Allocate buffer for interrupt data */
265         pdata->urbdata = usb_buffer_alloc(pdata->udev, ACD_URB_BUFFER_LEN,
266                 GFP_KERNEL, &pdata->urb->transfer_dma);
267         if (!pdata->urbdata) {
268                 retval = -ENOMEM;
269                 err("appledisplay: Allocating URB buffer failed");
270                 goto error;
271         }
272
273         /* Configure interrupt URB */
274         usb_fill_int_urb(pdata->urb, udev,
275                 usb_rcvintpipe(udev, int_in_endpointAddr),
276                 pdata->urbdata, ACD_URB_BUFFER_LEN, appledisplay_complete,
277                 pdata, 1);
278         if (usb_submit_urb(pdata->urb, GFP_KERNEL)) {
279                 retval = -EIO;
280                 err("appledisplay: Submitting URB failed");
281                 goto error;
282         }
283
284         /* Register backlight device */
285         snprintf(bl_name, sizeof(bl_name), "appledisplay%d",
286                 atomic_inc_return(&count_displays) - 1);
287         pdata->bd = backlight_device_register(bl_name, pdata,
288                                                 &appledisplay_bl_data);
289         if (IS_ERR(pdata->bd)) {
290                 err("appledisplay: Backlight registration failed");
291                 goto error;
292         }
293
294         /* Try to get brightness */
295         up(&pdata->bd->sem);
296         brightness = appledisplay_bl_get_brightness(pdata->bd);
297         down(&pdata->bd->sem);
298
299         if (brightness < 0) {
300                 retval = brightness;
301                 err("appledisplay: Error while getting initial brightness: %d", retval);
302                 goto error;
303         }
304
305         /* Set brightness in backlight device */
306         up(&pdata->bd->sem);
307         pdata->bd->props->brightness = brightness;
308         down(&pdata->bd->sem);
309
310         /* save our data pointer in the interface device */
311         usb_set_intfdata(iface, pdata);
312
313         printk(KERN_INFO "appledisplay: Apple Cinema Display connected\n");
314
315         return 0;
316
317 error:
318         if (pdata) {
319                 if (pdata->urb) {
320                         usb_kill_urb(pdata->urb);
321                         if (pdata->urbdata)
322                                 usb_buffer_free(pdata->udev, ACD_URB_BUFFER_LEN,
323                                         pdata->urbdata, pdata->urb->transfer_dma);
324                         usb_free_urb(pdata->urb);
325                 }
326                 if (pdata->bd)
327                         backlight_device_unregister(pdata->bd);
328                 kfree(pdata->msgdata);
329         }
330         usb_set_intfdata(iface, NULL);
331         kfree(pdata);
332         return retval;
333 }
334
335 static void appledisplay_disconnect(struct usb_interface *iface)
336 {
337         struct appledisplay *pdata = usb_get_intfdata(iface);
338
339         if (pdata) {
340                 usb_kill_urb(pdata->urb);
341                 cancel_delayed_work(&pdata->work);
342                 backlight_device_unregister(pdata->bd);
343                 usb_buffer_free(pdata->udev, ACD_URB_BUFFER_LEN,
344                         pdata->urbdata, pdata->urb->transfer_dma);
345                 usb_free_urb(pdata->urb);
346                 kfree(pdata->msgdata);
347                 kfree(pdata);
348         }
349
350         printk(KERN_INFO "appledisplay: Apple Cinema Display disconnected\n");
351 }
352
353 static struct usb_driver appledisplay_driver = {
354         .name           = "appledisplay",
355         .probe          = appledisplay_probe,
356         .disconnect     = appledisplay_disconnect,
357         .id_table       = appledisplay_table,
358 };
359
360 static int __init appledisplay_init(void)
361 {
362         wq = create_singlethread_workqueue("appledisplay");
363         if (!wq) {
364                 err("Could not create work queue\n");
365                 return -ENOMEM;
366         }
367
368         return usb_register(&appledisplay_driver);
369 }
370
371 static void __exit appledisplay_exit(void)
372 {
373         flush_workqueue(wq);
374         destroy_workqueue(wq);
375         usb_deregister(&appledisplay_driver);
376 }
377
378 MODULE_AUTHOR("Michael Hanselmann");
379 MODULE_DESCRIPTION("Apple Cinema Display driver");
380 MODULE_LICENSE("GPL");
381
382 module_init(appledisplay_init);
383 module_exit(appledisplay_exit);