094f91cbc5780b78ab9f3eb67c1d87c1583b9cd8
[linux-2.6.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/kernel.h>
24 #include <linux/errno.h>
25 #include <linux/init.h>
26 #include <linux/module.h>
27 #include <linux/slab.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
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 const struct usb_device_id appledisplay_table[] = {
62         { APPLEDISPLAY_DEVICE(0x9218) },
63         { APPLEDISPLAY_DEVICE(0x9219) },
64         { APPLEDISPLAY_DEVICE(0x921c) },
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         u8 *urbdata;                    /* interrupt URB data buffer */
78         u8 *msgdata;                    /* control message data buffer */
79
80         struct delayed_work 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)
89 {
90         struct appledisplay *pdata = urb->context;
91         unsigned long flags;
92         int status = urb->status;
93         int retval;
94
95         switch (status) {
96         case 0:
97                 /* success */
98                 break;
99         case -EOVERFLOW:
100                 printk(KERN_ERR "appletouch: OVERFLOW with data "
101                         "length %d, actual length is %d\n",
102                         ACD_URB_BUFFER_LEN, pdata->urb->actual_length);
103         case -ECONNRESET:
104         case -ENOENT:
105         case -ESHUTDOWN:
106                 /* This urb is terminated, clean up */
107                 dbg("%s - urb shuttingdown with status: %d",
108                         __func__, status);
109                 return;
110         default:
111                 dbg("%s - nonzero urb status received: %d",
112                         __func__, status);
113                 goto exit;
114         }
115
116         spin_lock_irqsave(&pdata->lock, flags);
117
118         switch(pdata->urbdata[1]) {
119         case ACD_BTN_BRIGHT_UP:
120         case ACD_BTN_BRIGHT_DOWN:
121                 pdata->button_pressed = 1;
122                 queue_delayed_work(wq, &pdata->work, 0);
123                 break;
124         case ACD_BTN_NONE:
125         default:
126                 pdata->button_pressed = 0;
127                 break;
128         }
129
130         spin_unlock_irqrestore(&pdata->lock, flags);
131
132 exit:
133         retval = usb_submit_urb(pdata->urb, GFP_ATOMIC);
134         if (retval) {
135                 dev_err(&pdata->udev->dev,
136                         "%s - usb_submit_urb failed with result %d\n",
137                         __func__, retval);
138         }
139 }
140
141 static int appledisplay_bl_update_status(struct backlight_device *bd)
142 {
143         struct appledisplay *pdata = bl_get_data(bd);
144         int retval;
145
146         pdata->msgdata[0] = 0x10;
147         pdata->msgdata[1] = bd->props.brightness;
148
149         retval = usb_control_msg(
150                 pdata->udev,
151                 usb_sndctrlpipe(pdata->udev, 0),
152                 USB_REQ_SET_REPORT,
153                 USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
154                 ACD_USB_BRIGHTNESS,
155                 0,
156                 pdata->msgdata, 2,
157                 ACD_USB_TIMEOUT);
158
159         return retval;
160 }
161
162 static int appledisplay_bl_get_brightness(struct backlight_device *bd)
163 {
164         struct appledisplay *pdata = bl_get_data(bd);
165         int retval;
166
167         retval = usb_control_msg(
168                 pdata->udev,
169                 usb_rcvctrlpipe(pdata->udev, 0),
170                 USB_REQ_GET_REPORT,
171                 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
172                 ACD_USB_BRIGHTNESS,
173                 0,
174                 pdata->msgdata, 2,
175                 ACD_USB_TIMEOUT);
176
177         if (retval < 0)
178                 return retval;
179         else
180                 return pdata->msgdata[1];
181 }
182
183 static const struct backlight_ops appledisplay_bl_data = {
184         .get_brightness = appledisplay_bl_get_brightness,
185         .update_status  = appledisplay_bl_update_status,
186 };
187
188 static void appledisplay_work(struct work_struct *work)
189 {
190         struct appledisplay *pdata =
191                 container_of(work, struct appledisplay, work.work);
192         int retval;
193
194         retval = appledisplay_bl_get_brightness(pdata->bd);
195         if (retval >= 0)
196                 pdata->bd->props.brightness = retval;
197
198         /* Poll again in about 125ms if there's still a button pressed */
199         if (pdata->button_pressed)
200                 schedule_delayed_work(&pdata->work, HZ / 8);
201 }
202
203 static int appledisplay_probe(struct usb_interface *iface,
204         const struct usb_device_id *id)
205 {
206         struct backlight_properties props;
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 && usb_endpoint_is_int_in(endpoint)) {
221                         /* we found an interrupt in endpoint */
222                         int_in_endpointAddr = endpoint->bEndpointAddress;
223                         break;
224                 }
225         }
226         if (!int_in_endpointAddr) {
227                 dev_err(&iface->dev, "Could not find int-in endpoint\n");
228                 return -EIO;
229         }
230
231         /* allocate memory for our device state and initialize it */
232         pdata = kzalloc(sizeof(struct appledisplay), GFP_KERNEL);
233         if (!pdata) {
234                 retval = -ENOMEM;
235                 dev_err(&iface->dev, "Out of memory\n");
236                 goto error;
237         }
238
239         pdata->udev = udev;
240
241         spin_lock_init(&pdata->lock);
242         INIT_DELAYED_WORK(&pdata->work, appledisplay_work);
243
244         /* Allocate buffer for control messages */
245         pdata->msgdata = kmalloc(ACD_MSG_BUFFER_LEN, GFP_KERNEL);
246         if (!pdata->msgdata) {
247                 retval = -ENOMEM;
248                 dev_err(&iface->dev,
249                         "Allocating buffer for control messages failed\n");
250                 goto error;
251         }
252
253         /* Allocate interrupt URB */
254         pdata->urb = usb_alloc_urb(0, GFP_KERNEL);
255         if (!pdata->urb) {
256                 retval = -ENOMEM;
257                 dev_err(&iface->dev, "Allocating URB failed\n");
258                 goto error;
259         }
260
261         /* Allocate buffer for interrupt data */
262         pdata->urbdata = usb_buffer_alloc(pdata->udev, ACD_URB_BUFFER_LEN,
263                 GFP_KERNEL, &pdata->urb->transfer_dma);
264         if (!pdata->urbdata) {
265                 retval = -ENOMEM;
266                 dev_err(&iface->dev, "Allocating URB buffer failed\n");
267                 goto error;
268         }
269
270         /* Configure interrupt URB */
271         usb_fill_int_urb(pdata->urb, udev,
272                 usb_rcvintpipe(udev, int_in_endpointAddr),
273                 pdata->urbdata, ACD_URB_BUFFER_LEN, appledisplay_complete,
274                 pdata, 1);
275         if (usb_submit_urb(pdata->urb, GFP_KERNEL)) {
276                 retval = -EIO;
277                 dev_err(&iface->dev, "Submitting URB failed\n");
278                 goto error;
279         }
280
281         /* Register backlight device */
282         snprintf(bl_name, sizeof(bl_name), "appledisplay%d",
283                 atomic_inc_return(&count_displays) - 1);
284         memset(&props, 0, sizeof(struct backlight_properties));
285         props.max_brightness = 0xff;
286         pdata->bd = backlight_device_register(bl_name, NULL, pdata,
287                                               &appledisplay_bl_data, &props);
288         if (IS_ERR(pdata->bd)) {
289                 dev_err(&iface->dev, "Backlight registration failed\n");
290                 retval = PTR_ERR(pdata->bd);
291                 goto error;
292         }
293
294         /* Try to get brightness */
295         brightness = appledisplay_bl_get_brightness(pdata->bd);
296
297         if (brightness < 0) {
298                 retval = brightness;
299                 dev_err(&iface->dev,
300                         "Error while getting initial brightness: %d\n", retval);
301                 goto error;
302         }
303
304         /* Set brightness in backlight device */
305         pdata->bd->props.brightness = brightness;
306
307         /* save our data pointer in the interface device */
308         usb_set_intfdata(iface, pdata);
309
310         printk(KERN_INFO "appledisplay: Apple Cinema Display connected\n");
311
312         return 0;
313
314 error:
315         if (pdata) {
316                 if (pdata->urb) {
317                         usb_kill_urb(pdata->urb);
318                         if (pdata->urbdata)
319                                 usb_buffer_free(pdata->udev, ACD_URB_BUFFER_LEN,
320                                         pdata->urbdata, pdata->urb->transfer_dma);
321                         usb_free_urb(pdata->urb);
322                 }
323                 if (pdata->bd && !IS_ERR(pdata->bd))
324                         backlight_device_unregister(pdata->bd);
325                 kfree(pdata->msgdata);
326         }
327         usb_set_intfdata(iface, NULL);
328         kfree(pdata);
329         return retval;
330 }
331
332 static void appledisplay_disconnect(struct usb_interface *iface)
333 {
334         struct appledisplay *pdata = usb_get_intfdata(iface);
335
336         if (pdata) {
337                 usb_kill_urb(pdata->urb);
338                 cancel_delayed_work(&pdata->work);
339                 backlight_device_unregister(pdata->bd);
340                 usb_buffer_free(pdata->udev, ACD_URB_BUFFER_LEN,
341                         pdata->urbdata, pdata->urb->transfer_dma);
342                 usb_free_urb(pdata->urb);
343                 kfree(pdata->msgdata);
344                 kfree(pdata);
345         }
346
347         printk(KERN_INFO "appledisplay: Apple Cinema Display disconnected\n");
348 }
349
350 static struct usb_driver appledisplay_driver = {
351         .name           = "appledisplay",
352         .probe          = appledisplay_probe,
353         .disconnect     = appledisplay_disconnect,
354         .id_table       = appledisplay_table,
355 };
356
357 static int __init appledisplay_init(void)
358 {
359         wq = create_singlethread_workqueue("appledisplay");
360         if (!wq) {
361                 printk(KERN_ERR "appledisplay: Could not create work queue\n");
362                 return -ENOMEM;
363         }
364
365         return usb_register(&appledisplay_driver);
366 }
367
368 static void __exit appledisplay_exit(void)
369 {
370         flush_workqueue(wq);
371         destroy_workqueue(wq);
372         usb_deregister(&appledisplay_driver);
373 }
374
375 MODULE_AUTHOR("Michael Hanselmann");
376 MODULE_DESCRIPTION("Apple Cinema Display driver");
377 MODULE_LICENSE("GPL");
378
379 module_init(appledisplay_init);
380 module_exit(appledisplay_exit);