Pull ec into release branch
[linux-2.6] / 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/kernel.h>
24 #include <linux/errno.h>
25 #include <linux/init.h>
26 #include <linux/module.h>
27 #include <linux/usb.h>
28 #include <linux/backlight.h>
29 #include <linux/timer.h>
30 #include <linux/workqueue.h>
31 #include <asm/atomic.h>
32 #include <asm/semaphore.h>
33
34 #define APPLE_VENDOR_ID         0x05AC
35
36 #define USB_REQ_GET_REPORT      0x01
37 #define USB_REQ_SET_REPORT      0x09
38
39 #define ACD_USB_TIMEOUT         250
40
41 #define ACD_USB_EDID            0x0302
42 #define ACD_USB_BRIGHTNESS      0x0310
43
44 #define ACD_BTN_NONE            0
45 #define ACD_BTN_BRIGHT_UP       3
46 #define ACD_BTN_BRIGHT_DOWN     4
47
48 #define ACD_URB_BUFFER_LEN      2
49 #define ACD_MSG_BUFFER_LEN      2
50
51 #define APPLEDISPLAY_DEVICE(prod)                               \
52         .match_flags = USB_DEVICE_ID_MATCH_DEVICE |             \
53                        USB_DEVICE_ID_MATCH_INT_CLASS |          \
54                        USB_DEVICE_ID_MATCH_INT_PROTOCOL,        \
55         .idVendor = APPLE_VENDOR_ID,                            \
56         .idProduct = (prod),                                    \
57         .bInterfaceClass = USB_CLASS_HID,                       \
58         .bInterfaceProtocol = 0x00
59
60 /* table of devices that work with this driver */
61 static struct usb_device_id appledisplay_table [] = {
62         { APPLEDISPLAY_DEVICE(0x9218) },
63         { APPLEDISPLAY_DEVICE(0x9219) },
64         { APPLEDISPLAY_DEVICE(0x921d) },
65
66         /* Terminating entry */
67         { }
68 };
69 MODULE_DEVICE_TABLE(usb, appledisplay_table);
70
71 /* Structure to hold all of our device specific stuff */
72 struct appledisplay {
73         struct usb_device *udev;        /* usb device */
74         struct urb *urb;                /* usb request block */
75         struct backlight_device *bd;    /* backlight device */
76         char *urbdata;                  /* interrupt URB data buffer */
77         char *msgdata;                  /* control message data buffer */
78
79         struct delayed_work work;
80         int button_pressed;
81         spinlock_t lock;
82 };
83
84 static atomic_t count_displays = ATOMIC_INIT(0);
85 static struct workqueue_struct *wq;
86
87 static void appledisplay_complete(struct urb *urb)
88 {
89         struct appledisplay *pdata = urb->context;
90         unsigned long flags;
91         int status = urb->status;
92         int retval;
93
94         switch (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 shuttingdown with status: %d",
107                         __FUNCTION__, status);
108                 return;
109         default:
110                 dbg("%s - nonzero urb status received: %d",
111                         __FUNCTION__, 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_delayed_work(wq, &pdata->work, 0);
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_ops appledisplay_bl_data = {
182         .get_brightness = appledisplay_bl_get_brightness,
183         .update_status  = appledisplay_bl_update_status,
184 };
185
186 static void appledisplay_work(struct work_struct *work)
187 {
188         struct appledisplay *pdata =
189                 container_of(work, struct appledisplay, work.work);
190         int retval;
191
192         retval = appledisplay_bl_get_brightness(pdata->bd);
193         if (retval >= 0)
194                 pdata->bd->props.brightness = retval;
195
196         /* Poll again in about 125ms if there's still a button pressed */
197         if (pdata->button_pressed)
198                 schedule_delayed_work(&pdata->work, HZ / 8);
199 }
200
201 static int appledisplay_probe(struct usb_interface *iface,
202         const struct usb_device_id *id)
203 {
204         struct appledisplay *pdata;
205         struct usb_device *udev = interface_to_usbdev(iface);
206         struct usb_host_interface *iface_desc;
207         struct usb_endpoint_descriptor *endpoint;
208         int int_in_endpointAddr = 0;
209         int i, retval = -ENOMEM, brightness;
210         char bl_name[20];
211
212         /* set up the endpoint information */
213         /* use only the first interrupt-in endpoint */
214         iface_desc = iface->cur_altsetting;
215         for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
216                 endpoint = &iface_desc->endpoint[i].desc;
217                 if (!int_in_endpointAddr && usb_endpoint_is_int_in(endpoint)) {
218                         /* we found an interrupt in endpoint */
219                         int_in_endpointAddr = endpoint->bEndpointAddress;
220                         break;
221                 }
222         }
223         if (!int_in_endpointAddr) {
224                 err("Could not find int-in endpoint");
225                 return -EIO;
226         }
227
228         /* allocate memory for our device state and initialize it */
229         pdata = kzalloc(sizeof(struct appledisplay), GFP_KERNEL);
230         if (!pdata) {
231                 retval = -ENOMEM;
232                 err("Out of memory");
233                 goto error;
234         }
235
236         pdata->udev = udev;
237
238         spin_lock_init(&pdata->lock);
239         INIT_DELAYED_WORK(&pdata->work, appledisplay_work);
240
241         /* Allocate buffer for control messages */
242         pdata->msgdata = kmalloc(ACD_MSG_BUFFER_LEN, GFP_KERNEL);
243         if (!pdata->msgdata) {
244                 retval = -ENOMEM;
245                 err("appledisplay: Allocating buffer for control messages "
246                         "failed");
247                 goto error;
248         }
249
250         /* Allocate interrupt URB */
251         pdata->urb = usb_alloc_urb(0, GFP_KERNEL);
252         if (!pdata->urb) {
253                 retval = -ENOMEM;
254                 err("appledisplay: Allocating URB failed");
255                 goto error;
256         }
257
258         /* Allocate buffer for interrupt data */
259         pdata->urbdata = usb_buffer_alloc(pdata->udev, ACD_URB_BUFFER_LEN,
260                 GFP_KERNEL, &pdata->urb->transfer_dma);
261         if (!pdata->urbdata) {
262                 retval = -ENOMEM;
263                 err("appledisplay: Allocating URB buffer failed");
264                 goto error;
265         }
266
267         /* Configure interrupt URB */
268         usb_fill_int_urb(pdata->urb, udev,
269                 usb_rcvintpipe(udev, int_in_endpointAddr),
270                 pdata->urbdata, ACD_URB_BUFFER_LEN, appledisplay_complete,
271                 pdata, 1);
272         if (usb_submit_urb(pdata->urb, GFP_KERNEL)) {
273                 retval = -EIO;
274                 err("appledisplay: Submitting URB failed");
275                 goto error;
276         }
277
278         /* Register backlight device */
279         snprintf(bl_name, sizeof(bl_name), "appledisplay%d",
280                 atomic_inc_return(&count_displays) - 1);
281         pdata->bd = backlight_device_register(bl_name, NULL, pdata,
282                                                 &appledisplay_bl_data);
283         if (IS_ERR(pdata->bd)) {
284                 err("appledisplay: Backlight registration failed");
285                 goto error;
286         }
287
288         pdata->bd->props.max_brightness = 0xff;
289
290         /* Try to get brightness */
291         brightness = appledisplay_bl_get_brightness(pdata->bd);
292
293         if (brightness < 0) {
294                 retval = brightness;
295                 err("appledisplay: Error while getting initial brightness: %d", retval);
296                 goto error;
297         }
298
299         /* Set brightness in backlight device */
300         pdata->bd->props.brightness = brightness;
301
302         /* save our data pointer in the interface device */
303         usb_set_intfdata(iface, pdata);
304
305         printk(KERN_INFO "appledisplay: Apple Cinema Display connected\n");
306
307         return 0;
308
309 error:
310         if (pdata) {
311                 if (pdata->urb) {
312                         usb_kill_urb(pdata->urb);
313                         if (pdata->urbdata)
314                                 usb_buffer_free(pdata->udev, ACD_URB_BUFFER_LEN,
315                                         pdata->urbdata, pdata->urb->transfer_dma);
316                         usb_free_urb(pdata->urb);
317                 }
318                 if (pdata->bd)
319                         backlight_device_unregister(pdata->bd);
320                 kfree(pdata->msgdata);
321         }
322         usb_set_intfdata(iface, NULL);
323         kfree(pdata);
324         return retval;
325 }
326
327 static void appledisplay_disconnect(struct usb_interface *iface)
328 {
329         struct appledisplay *pdata = usb_get_intfdata(iface);
330
331         if (pdata) {
332                 usb_kill_urb(pdata->urb);
333                 cancel_delayed_work(&pdata->work);
334                 backlight_device_unregister(pdata->bd);
335                 usb_buffer_free(pdata->udev, ACD_URB_BUFFER_LEN,
336                         pdata->urbdata, pdata->urb->transfer_dma);
337                 usb_free_urb(pdata->urb);
338                 kfree(pdata->msgdata);
339                 kfree(pdata);
340         }
341
342         printk(KERN_INFO "appledisplay: Apple Cinema Display disconnected\n");
343 }
344
345 static struct usb_driver appledisplay_driver = {
346         .name           = "appledisplay",
347         .probe          = appledisplay_probe,
348         .disconnect     = appledisplay_disconnect,
349         .id_table       = appledisplay_table,
350 };
351
352 static int __init appledisplay_init(void)
353 {
354         wq = create_singlethread_workqueue("appledisplay");
355         if (!wq) {
356                 err("Could not create work queue\n");
357                 return -ENOMEM;
358         }
359
360         return usb_register(&appledisplay_driver);
361 }
362
363 static void __exit appledisplay_exit(void)
364 {
365         flush_workqueue(wq);
366         destroy_workqueue(wq);
367         usb_deregister(&appledisplay_driver);
368 }
369
370 MODULE_AUTHOR("Michael Hanselmann");
371 MODULE_DESCRIPTION("Apple Cinema Display driver");
372 MODULE_LICENSE("GPL");
373
374 module_init(appledisplay_init);
375 module_exit(appledisplay_exit);