2 * Apple Cinema Display driver
4 * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
6 * Thanks to Caskey L. Dickson for his work with acdctl.
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.
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.
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.
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>
34 #define APPLE_VENDOR_ID 0x05AC
36 #define USB_REQ_GET_REPORT 0x01
37 #define USB_REQ_SET_REPORT 0x09
39 #define ACD_USB_TIMEOUT 250
41 #define ACD_USB_EDID 0x0302
42 #define ACD_USB_BRIGHTNESS 0x0310
44 #define ACD_BTN_NONE 0
45 #define ACD_BTN_BRIGHT_UP 3
46 #define ACD_BTN_BRIGHT_DOWN 4
48 #define ACD_URB_BUFFER_LEN 2
49 #define ACD_MSG_BUFFER_LEN 2
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
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) },
66 /* Terminating entry */
69 MODULE_DEVICE_TABLE(usb
, appledisplay_table
);
71 /* Structure to hold all of our device specific stuff */
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 */
79 struct work_struct work
;
84 static atomic_t count_displays
= ATOMIC_INIT(0);
85 static struct workqueue_struct
*wq
;
87 static void appledisplay_complete(struct urb
*urb
)
89 struct appledisplay
*pdata
= urb
->context
;
93 switch (urb
->status
) {
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
);
104 /* This urb is terminated, clean up */
105 dbg("%s - urb shutting down with status: %d",
106 __FUNCTION__
, urb
->status
);
109 dbg("%s - nonzero urb status received: %d",
110 __FUNCTION__
, urb
->status
);
114 spin_lock_irqsave(&pdata
->lock
, flags
);
116 switch(pdata
->urbdata
[1]) {
117 case ACD_BTN_BRIGHT_UP
:
118 case ACD_BTN_BRIGHT_DOWN
:
119 pdata
->button_pressed
= 1;
120 queue_work(wq
, &pdata
->work
);
124 pdata
->button_pressed
= 0;
128 spin_unlock_irqrestore(&pdata
->lock
, flags
);
131 retval
= usb_submit_urb(pdata
->urb
, GFP_ATOMIC
);
133 err("%s - usb_submit_urb failed with result %d",
134 __FUNCTION__
, retval
);
138 static int appledisplay_bl_update_status(struct backlight_device
*bd
)
140 struct appledisplay
*pdata
= class_get_devdata(&bd
->class_dev
);
143 pdata
->msgdata
[0] = 0x10;
144 pdata
->msgdata
[1] = bd
->props
->brightness
;
146 retval
= usb_control_msg(
148 usb_sndctrlpipe(pdata
->udev
, 0),
150 USB_DIR_OUT
| USB_TYPE_CLASS
| USB_RECIP_INTERFACE
,
159 static int appledisplay_bl_get_brightness(struct backlight_device
*bd
)
161 struct appledisplay
*pdata
= class_get_devdata(&bd
->class_dev
);
164 retval
= usb_control_msg(
166 usb_rcvctrlpipe(pdata
->udev
, 0),
168 USB_DIR_IN
| USB_TYPE_CLASS
| USB_RECIP_INTERFACE
,
177 return pdata
->msgdata
[1];
180 static struct backlight_properties appledisplay_bl_data
= {
181 .owner
= THIS_MODULE
,
182 .get_brightness
= appledisplay_bl_get_brightness
,
183 .update_status
= appledisplay_bl_update_status
,
184 .max_brightness
= 0xFF
187 static void appledisplay_work(void *private)
189 struct appledisplay
*pdata
= private;
193 retval
= appledisplay_bl_get_brightness(pdata
->bd
);
195 pdata
->bd
->props
->brightness
= retval
;
196 down(&pdata
->bd
->sem
);
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);
203 static int appledisplay_probe(struct usb_interface
*iface
,
204 const struct usb_device_id
*id
)
206 struct appledisplay
*pdata
;
207 struct usb_device
*udev
= interface_to_usbdev(iface
);
208 struct usb_host_interface
*iface_desc
;
209 struct usb_endpoint_descriptor
*endpoint
;
210 int int_in_endpointAddr
= 0;
211 int i
, retval
= -ENOMEM
, brightness
;
214 /* set up the endpoint information */
215 /* use only the first interrupt-in endpoint */
216 iface_desc
= iface
->cur_altsetting
;
217 for (i
= 0; i
< iface_desc
->desc
.bNumEndpoints
; i
++) {
218 endpoint
= &iface_desc
->endpoint
[i
].desc
;
219 if (!int_in_endpointAddr
&&
220 (endpoint
->bEndpointAddress
& USB_DIR_IN
) &&
221 ((endpoint
->bmAttributes
& USB_ENDPOINT_XFERTYPE_MASK
) ==
222 USB_ENDPOINT_XFER_INT
)) {
223 /* we found an interrupt in endpoint */
224 int_in_endpointAddr
= endpoint
->bEndpointAddress
;
228 if (!int_in_endpointAddr
) {
229 err("Could not find int-in endpoint");
233 /* allocate memory for our device state and initialize it */
234 pdata
= kzalloc(sizeof(struct appledisplay
), GFP_KERNEL
);
237 err("Out of memory");
243 spin_lock_init(&pdata
->lock
);
244 INIT_WORK(&pdata
->work
, appledisplay_work
, pdata
);
246 /* Allocate buffer for control messages */
247 pdata
->msgdata
= kmalloc(ACD_MSG_BUFFER_LEN
, GFP_KERNEL
);
248 if (!pdata
->msgdata
) {
250 err("appledisplay: Allocating buffer for control messages "
255 /* Allocate interrupt URB */
256 pdata
->urb
= usb_alloc_urb(0, GFP_KERNEL
);
259 err("appledisplay: Allocating URB failed");
263 /* Allocate buffer for interrupt data */
264 pdata
->urbdata
= usb_buffer_alloc(pdata
->udev
, ACD_URB_BUFFER_LEN
,
265 GFP_KERNEL
, &pdata
->urb
->transfer_dma
);
266 if (!pdata
->urbdata
) {
268 err("appledisplay: Allocating URB buffer failed");
272 /* Configure interrupt URB */
273 usb_fill_int_urb(pdata
->urb
, udev
,
274 usb_rcvintpipe(udev
, int_in_endpointAddr
),
275 pdata
->urbdata
, ACD_URB_BUFFER_LEN
, appledisplay_complete
,
277 if (usb_submit_urb(pdata
->urb
, GFP_KERNEL
)) {
279 err("appledisplay: Submitting URB failed");
283 /* Register backlight device */
284 snprintf(bl_name
, sizeof(bl_name
), "appledisplay%d",
285 atomic_inc_return(&count_displays
) - 1);
286 pdata
->bd
= backlight_device_register(bl_name
, pdata
,
287 &appledisplay_bl_data
);
288 if (IS_ERR(pdata
->bd
)) {
289 err("appledisplay: Backlight registration failed");
293 /* Try to get brightness */
295 brightness
= appledisplay_bl_get_brightness(pdata
->bd
);
296 down(&pdata
->bd
->sem
);
298 if (brightness
< 0) {
300 err("appledisplay: Error while getting initial brightness: %d", retval
);
304 /* Set brightness in backlight device */
306 pdata
->bd
->props
->brightness
= brightness
;
307 down(&pdata
->bd
->sem
);
309 /* save our data pointer in the interface device */
310 usb_set_intfdata(iface
, pdata
);
312 printk(KERN_INFO
"appledisplay: Apple Cinema Display connected\n");
319 usb_kill_urb(pdata
->urb
);
321 usb_buffer_free(pdata
->udev
, ACD_URB_BUFFER_LEN
,
322 pdata
->urbdata
, pdata
->urb
->transfer_dma
);
323 usb_free_urb(pdata
->urb
);
326 backlight_device_unregister(pdata
->bd
);
327 kfree(pdata
->msgdata
);
329 usb_set_intfdata(iface
, NULL
);
334 static void appledisplay_disconnect(struct usb_interface
*iface
)
336 struct appledisplay
*pdata
= usb_get_intfdata(iface
);
339 usb_kill_urb(pdata
->urb
);
340 cancel_delayed_work(&pdata
->work
);
341 backlight_device_unregister(pdata
->bd
);
342 usb_buffer_free(pdata
->udev
, ACD_URB_BUFFER_LEN
,
343 pdata
->urbdata
, pdata
->urb
->transfer_dma
);
344 usb_free_urb(pdata
->urb
);
345 kfree(pdata
->msgdata
);
349 printk(KERN_INFO
"appledisplay: Apple Cinema Display disconnected\n");
352 static struct usb_driver appledisplay_driver
= {
353 .name
= "appledisplay",
354 .probe
= appledisplay_probe
,
355 .disconnect
= appledisplay_disconnect
,
356 .id_table
= appledisplay_table
,
359 static int __init
appledisplay_init(void)
361 wq
= create_singlethread_workqueue("appledisplay");
363 err("Could not create work queue\n");
367 return usb_register(&appledisplay_driver
);
370 static void __exit
appledisplay_exit(void)
373 destroy_workqueue(wq
);
374 usb_deregister(&appledisplay_driver
);
377 MODULE_AUTHOR("Michael Hanselmann");
378 MODULE_DESCRIPTION("Apple Cinema Display driver");
379 MODULE_LICENSE("GPL");
381 module_init(appledisplay_init
);
382 module_exit(appledisplay_exit
);