Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc
[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
33 #define APPLE_VENDOR_ID         0x05AC
34
35 #define USB_REQ_GET_REPORT      0x01
36 #define USB_REQ_SET_REPORT      0x09
37
38 #define ACD_USB_TIMEOUT         250
39
40 #define ACD_USB_EDID            0x0302
41 #define ACD_USB_BRIGHTNESS      0x0310
42
43 #define ACD_BTN_NONE            0
44 #define ACD_BTN_BRIGHT_UP       3
45 #define ACD_BTN_BRIGHT_DOWN     4
46
47 #define ACD_URB_BUFFER_LEN      2
48 #define ACD_MSG_BUFFER_LEN      2
49
50 #define APPLEDISPLAY_DEVICE(prod)                               \
51         .match_flags = USB_DEVICE_ID_MATCH_DEVICE |             \
52                        USB_DEVICE_ID_MATCH_INT_CLASS |          \
53                        USB_DEVICE_ID_MATCH_INT_PROTOCOL,        \
54         .idVendor = APPLE_VENDOR_ID,                            \
55         .idProduct = (prod),                                    \
56         .bInterfaceClass = USB_CLASS_HID,                       \
57         .bInterfaceProtocol = 0x00
58
59 /* table of devices that work with this driver */
60 static struct usb_device_id appledisplay_table [] = {
61         { APPLEDISPLAY_DEVICE(0x9218) },
62         { APPLEDISPLAY_DEVICE(0x9219) },
63         { APPLEDISPLAY_DEVICE(0x921d) },
64
65         /* Terminating entry */
66         { }
67 };
68 MODULE_DEVICE_TABLE(usb, appledisplay_table);
69
70 /* Structure to hold all of our device specific stuff */
71 struct appledisplay {
72         struct usb_device *udev;        /* usb device */
73         struct urb *urb;                /* usb request block */
74         struct backlight_device *bd;    /* backlight device */
75         char *urbdata;                  /* interrupt URB data buffer */
76         char *msgdata;                  /* control message data buffer */
77
78         struct delayed_work work;
79         int button_pressed;
80         spinlock_t lock;
81 };
82
83 static atomic_t count_displays = ATOMIC_INIT(0);
84 static struct workqueue_struct *wq;
85
86 static void appledisplay_complete(struct urb *urb)
87 {
88         struct appledisplay *pdata = urb->context;
89         unsigned long flags;
90         int status = urb->status;
91         int retval;
92
93         switch (status) {
94         case 0:
95                 /* success */
96                 break;
97         case -EOVERFLOW:
98                 printk(KERN_ERR "appletouch: OVERFLOW with data "
99                         "length %d, actual length is %d\n",
100                         ACD_URB_BUFFER_LEN, pdata->urb->actual_length);
101         case -ECONNRESET:
102         case -ENOENT:
103         case -ESHUTDOWN:
104                 /* This urb is terminated, clean up */
105                 dbg("%s - urb shuttingdown with status: %d",
106                         __func__, status);
107                 return;
108         default:
109                 dbg("%s - nonzero urb status received: %d",
110                         __func__, status);
111                 goto exit;
112         }
113
114         spin_lock_irqsave(&pdata->lock, flags);
115
116         switch(pdata->urbdata[1]) {
117         case ACD_BTN_BRIGHT_UP:
118         case ACD_BTN_BRIGHT_DOWN:
119                 pdata->button_pressed = 1;
120                 queue_delayed_work(wq, &pdata->work, 0);
121                 break;
122         case ACD_BTN_NONE:
123         default:
124                 pdata->button_pressed = 0;
125                 break;
126         }
127
128         spin_unlock_irqrestore(&pdata->lock, flags);
129
130 exit:
131         retval = usb_submit_urb(pdata->urb, GFP_ATOMIC);
132         if (retval) {
133                 err("%s - usb_submit_urb failed with result %d",
134                         __func__, retval);
135         }
136 }
137
138 static int appledisplay_bl_update_status(struct backlight_device *bd)
139 {
140         struct appledisplay *pdata = bl_get_data(bd);
141         int retval;
142
143         pdata->msgdata[0] = 0x10;
144         pdata->msgdata[1] = bd->props.brightness;
145
146         retval = usb_control_msg(
147                 pdata->udev,
148                 usb_sndctrlpipe(pdata->udev, 0),
149                 USB_REQ_SET_REPORT,
150                 USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
151                 ACD_USB_BRIGHTNESS,
152                 0,
153                 pdata->msgdata, 2,
154                 ACD_USB_TIMEOUT);
155
156         return retval;
157 }
158
159 static int appledisplay_bl_get_brightness(struct backlight_device *bd)
160 {
161         struct appledisplay *pdata = bl_get_data(bd);
162         int retval;
163
164         retval = usb_control_msg(
165                 pdata->udev,
166                 usb_rcvctrlpipe(pdata->udev, 0),
167                 USB_REQ_GET_REPORT,
168                 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
169                 ACD_USB_BRIGHTNESS,
170                 0,
171                 pdata->msgdata, 2,
172                 ACD_USB_TIMEOUT);
173
174         if (retval < 0)
175                 return retval;
176         else
177                 return pdata->msgdata[1];
178 }
179
180 static struct backlight_ops appledisplay_bl_data = {
181         .get_brightness = appledisplay_bl_get_brightness,
182         .update_status  = appledisplay_bl_update_status,
183 };
184
185 static void appledisplay_work(struct work_struct *work)
186 {
187         struct appledisplay *pdata =
188                 container_of(work, struct appledisplay, work.work);
189         int retval;
190
191         retval = appledisplay_bl_get_brightness(pdata->bd);
192         if (retval >= 0)
193                 pdata->bd->props.brightness = retval;
194
195         /* Poll again in about 125ms if there's still a button pressed */
196         if (pdata->button_pressed)
197                 schedule_delayed_work(&pdata->work, HZ / 8);
198 }
199
200 static int appledisplay_probe(struct usb_interface *iface,
201         const struct usb_device_id *id)
202 {
203         struct appledisplay *pdata;
204         struct usb_device *udev = interface_to_usbdev(iface);
205         struct usb_host_interface *iface_desc;
206         struct usb_endpoint_descriptor *endpoint;
207         int int_in_endpointAddr = 0;
208         int i, retval = -ENOMEM, brightness;
209         char bl_name[20];
210
211         /* set up the endpoint information */
212         /* use only the first interrupt-in endpoint */
213         iface_desc = iface->cur_altsetting;
214         for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
215                 endpoint = &iface_desc->endpoint[i].desc;
216                 if (!int_in_endpointAddr && usb_endpoint_is_int_in(endpoint)) {
217                         /* we found an interrupt in endpoint */
218                         int_in_endpointAddr = endpoint->bEndpointAddress;
219                         break;
220                 }
221         }
222         if (!int_in_endpointAddr) {
223                 err("Could not find int-in endpoint");
224                 return -EIO;
225         }
226
227         /* allocate memory for our device state and initialize it */
228         pdata = kzalloc(sizeof(struct appledisplay), GFP_KERNEL);
229         if (!pdata) {
230                 retval = -ENOMEM;
231                 err("Out of memory");
232                 goto error;
233         }
234
235         pdata->udev = udev;
236
237         spin_lock_init(&pdata->lock);
238         INIT_DELAYED_WORK(&pdata->work, appledisplay_work);
239
240         /* Allocate buffer for control messages */
241         pdata->msgdata = kmalloc(ACD_MSG_BUFFER_LEN, GFP_KERNEL);
242         if (!pdata->msgdata) {
243                 retval = -ENOMEM;
244                 err("appledisplay: Allocating buffer for control messages "
245                         "failed");
246                 goto error;
247         }
248
249         /* Allocate interrupt URB */
250         pdata->urb = usb_alloc_urb(0, GFP_KERNEL);
251         if (!pdata->urb) {
252                 retval = -ENOMEM;
253                 err("appledisplay: Allocating URB failed");
254                 goto error;
255         }
256
257         /* Allocate buffer for interrupt data */
258         pdata->urbdata = usb_buffer_alloc(pdata->udev, ACD_URB_BUFFER_LEN,
259                 GFP_KERNEL, &pdata->urb->transfer_dma);
260         if (!pdata->urbdata) {
261                 retval = -ENOMEM;
262                 err("appledisplay: Allocating URB buffer failed");
263                 goto error;
264         }
265
266         /* Configure interrupt URB */
267         usb_fill_int_urb(pdata->urb, udev,
268                 usb_rcvintpipe(udev, int_in_endpointAddr),
269                 pdata->urbdata, ACD_URB_BUFFER_LEN, appledisplay_complete,
270                 pdata, 1);
271         if (usb_submit_urb(pdata->urb, GFP_KERNEL)) {
272                 retval = -EIO;
273                 err("appledisplay: Submitting URB failed");
274                 goto error;
275         }
276
277         /* Register backlight device */
278         snprintf(bl_name, sizeof(bl_name), "appledisplay%d",
279                 atomic_inc_return(&count_displays) - 1);
280         pdata->bd = backlight_device_register(bl_name, NULL, pdata,
281                                                 &appledisplay_bl_data);
282         if (IS_ERR(pdata->bd)) {
283                 err("appledisplay: Backlight registration failed");
284                 goto error;
285         }
286
287         pdata->bd->props.max_brightness = 0xff;
288
289         /* Try to get brightness */
290         brightness = appledisplay_bl_get_brightness(pdata->bd);
291
292         if (brightness < 0) {
293                 retval = brightness;
294                 err("appledisplay: Error while getting initial brightness: %d", retval);
295                 goto error;
296         }
297
298         /* Set brightness in backlight device */
299         pdata->bd->props.brightness = brightness;
300
301         /* save our data pointer in the interface device */
302         usb_set_intfdata(iface, pdata);
303
304         printk(KERN_INFO "appledisplay: Apple Cinema Display connected\n");
305
306         return 0;
307
308 error:
309         if (pdata) {
310                 if (pdata->urb) {
311                         usb_kill_urb(pdata->urb);
312                         if (pdata->urbdata)
313                                 usb_buffer_free(pdata->udev, ACD_URB_BUFFER_LEN,
314                                         pdata->urbdata, pdata->urb->transfer_dma);
315                         usb_free_urb(pdata->urb);
316                 }
317                 if (pdata->bd)
318                         backlight_device_unregister(pdata->bd);
319                 kfree(pdata->msgdata);
320         }
321         usb_set_intfdata(iface, NULL);
322         kfree(pdata);
323         return retval;
324 }
325
326 static void appledisplay_disconnect(struct usb_interface *iface)
327 {
328         struct appledisplay *pdata = usb_get_intfdata(iface);
329
330         if (pdata) {
331                 usb_kill_urb(pdata->urb);
332                 cancel_delayed_work(&pdata->work);
333                 backlight_device_unregister(pdata->bd);
334                 usb_buffer_free(pdata->udev, ACD_URB_BUFFER_LEN,
335                         pdata->urbdata, pdata->urb->transfer_dma);
336                 usb_free_urb(pdata->urb);
337                 kfree(pdata->msgdata);
338                 kfree(pdata);
339         }
340
341         printk(KERN_INFO "appledisplay: Apple Cinema Display disconnected\n");
342 }
343
344 static struct usb_driver appledisplay_driver = {
345         .name           = "appledisplay",
346         .probe          = appledisplay_probe,
347         .disconnect     = appledisplay_disconnect,
348         .id_table       = appledisplay_table,
349 };
350
351 static int __init appledisplay_init(void)
352 {
353         wq = create_singlethread_workqueue("appledisplay");
354         if (!wq) {
355                 err("Could not create work queue\n");
356                 return -ENOMEM;
357         }
358
359         return usb_register(&appledisplay_driver);
360 }
361
362 static void __exit appledisplay_exit(void)
363 {
364         flush_workqueue(wq);
365         destroy_workqueue(wq);
366         usb_deregister(&appledisplay_driver);
367 }
368
369 MODULE_AUTHOR("Michael Hanselmann");
370 MODULE_DESCRIPTION("Apple Cinema Display driver");
371 MODULE_LICENSE("GPL");
372
373 module_init(appledisplay_init);
374 module_exit(appledisplay_exit);