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>
33 #define APPLE_VENDOR_ID 0x05AC
35 #define USB_REQ_GET_REPORT 0x01
36 #define USB_REQ_SET_REPORT 0x09
38 #define ACD_USB_TIMEOUT 250
40 #define ACD_USB_EDID 0x0302
41 #define ACD_USB_BRIGHTNESS 0x0310
43 #define ACD_BTN_NONE 0
44 #define ACD_BTN_BRIGHT_UP 3
45 #define ACD_BTN_BRIGHT_DOWN 4
47 #define ACD_URB_BUFFER_LEN 2
48 #define ACD_MSG_BUFFER_LEN 2
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
59 /* table of devices that work with this driver */
60 static const struct usb_device_id appledisplay_table
[] = {
61 { APPLEDISPLAY_DEVICE(0x9218) },
62 { APPLEDISPLAY_DEVICE(0x9219) },
63 { APPLEDISPLAY_DEVICE(0x921c) },
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 u8
*urbdata
; /* interrupt URB data buffer */
77 u8
*msgdata
; /* control message data buffer */
79 struct delayed_work 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
;
91 int status
= urb
->status
;
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
);
105 /* This urb is terminated, clean up */
106 dbg("%s - urb shuttingdown with status: %d",
110 dbg("%s - nonzero urb status received: %d",
115 spin_lock_irqsave(&pdata
->lock
, flags
);
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);
125 pdata
->button_pressed
= 0;
129 spin_unlock_irqrestore(&pdata
->lock
, flags
);
132 retval
= usb_submit_urb(pdata
->urb
, GFP_ATOMIC
);
134 dev_err(&pdata
->udev
->dev
,
135 "%s - usb_submit_urb failed with result %d\n",
140 static int appledisplay_bl_update_status(struct backlight_device
*bd
)
142 struct appledisplay
*pdata
= bl_get_data(bd
);
145 pdata
->msgdata
[0] = 0x10;
146 pdata
->msgdata
[1] = bd
->props
.brightness
;
148 retval
= usb_control_msg(
150 usb_sndctrlpipe(pdata
->udev
, 0),
152 USB_DIR_OUT
| USB_TYPE_CLASS
| USB_RECIP_INTERFACE
,
161 static int appledisplay_bl_get_brightness(struct backlight_device
*bd
)
163 struct appledisplay
*pdata
= bl_get_data(bd
);
166 retval
= usb_control_msg(
168 usb_rcvctrlpipe(pdata
->udev
, 0),
170 USB_DIR_IN
| USB_TYPE_CLASS
| USB_RECIP_INTERFACE
,
179 return pdata
->msgdata
[1];
182 static const struct backlight_ops appledisplay_bl_data
= {
183 .get_brightness
= appledisplay_bl_get_brightness
,
184 .update_status
= appledisplay_bl_update_status
,
187 static void appledisplay_work(struct work_struct
*work
)
189 struct appledisplay
*pdata
=
190 container_of(work
, struct appledisplay
, work
.work
);
193 retval
= appledisplay_bl_get_brightness(pdata
->bd
);
195 pdata
->bd
->props
.brightness
= retval
;
197 /* Poll again in about 125ms if there's still a button pressed */
198 if (pdata
->button_pressed
)
199 schedule_delayed_work(&pdata
->work
, HZ
/ 8);
202 static int appledisplay_probe(struct usb_interface
*iface
,
203 const struct usb_device_id
*id
)
205 struct backlight_properties props
;
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
&& usb_endpoint_is_int_in(endpoint
)) {
220 /* we found an interrupt in endpoint */
221 int_in_endpointAddr
= endpoint
->bEndpointAddress
;
225 if (!int_in_endpointAddr
) {
226 dev_err(&iface
->dev
, "Could not find int-in endpoint\n");
230 /* allocate memory for our device state and initialize it */
231 pdata
= kzalloc(sizeof(struct appledisplay
), GFP_KERNEL
);
234 dev_err(&iface
->dev
, "Out of memory\n");
240 spin_lock_init(&pdata
->lock
);
241 INIT_DELAYED_WORK(&pdata
->work
, appledisplay_work
);
243 /* Allocate buffer for control messages */
244 pdata
->msgdata
= kmalloc(ACD_MSG_BUFFER_LEN
, GFP_KERNEL
);
245 if (!pdata
->msgdata
) {
248 "Allocating buffer for control messages failed\n");
252 /* Allocate interrupt URB */
253 pdata
->urb
= usb_alloc_urb(0, GFP_KERNEL
);
256 dev_err(&iface
->dev
, "Allocating URB failed\n");
260 /* Allocate buffer for interrupt data */
261 pdata
->urbdata
= usb_buffer_alloc(pdata
->udev
, ACD_URB_BUFFER_LEN
,
262 GFP_KERNEL
, &pdata
->urb
->transfer_dma
);
263 if (!pdata
->urbdata
) {
265 dev_err(&iface
->dev
, "Allocating URB buffer failed\n");
269 /* Configure interrupt URB */
270 usb_fill_int_urb(pdata
->urb
, udev
,
271 usb_rcvintpipe(udev
, int_in_endpointAddr
),
272 pdata
->urbdata
, ACD_URB_BUFFER_LEN
, appledisplay_complete
,
274 if (usb_submit_urb(pdata
->urb
, GFP_KERNEL
)) {
276 dev_err(&iface
->dev
, "Submitting URB failed\n");
280 /* Register backlight device */
281 snprintf(bl_name
, sizeof(bl_name
), "appledisplay%d",
282 atomic_inc_return(&count_displays
) - 1);
283 memset(&props
, 0, sizeof(struct backlight_properties
));
284 props
.max_brightness
= 0xff;
285 pdata
->bd
= backlight_device_register(bl_name
, NULL
, pdata
,
286 &appledisplay_bl_data
, &props
);
287 if (IS_ERR(pdata
->bd
)) {
288 dev_err(&iface
->dev
, "Backlight registration failed\n");
289 retval
= PTR_ERR(pdata
->bd
);
293 /* Try to get brightness */
294 brightness
= appledisplay_bl_get_brightness(pdata
->bd
);
296 if (brightness
< 0) {
299 "Error while getting initial brightness: %d\n", retval
);
303 /* Set brightness in backlight device */
304 pdata
->bd
->props
.brightness
= brightness
;
306 /* save our data pointer in the interface device */
307 usb_set_intfdata(iface
, pdata
);
309 printk(KERN_INFO
"appledisplay: Apple Cinema Display connected\n");
316 usb_kill_urb(pdata
->urb
);
318 usb_buffer_free(pdata
->udev
, ACD_URB_BUFFER_LEN
,
319 pdata
->urbdata
, pdata
->urb
->transfer_dma
);
320 usb_free_urb(pdata
->urb
);
322 if (pdata
->bd
&& !IS_ERR(pdata
->bd
))
323 backlight_device_unregister(pdata
->bd
);
324 kfree(pdata
->msgdata
);
326 usb_set_intfdata(iface
, NULL
);
331 static void appledisplay_disconnect(struct usb_interface
*iface
)
333 struct appledisplay
*pdata
= usb_get_intfdata(iface
);
336 usb_kill_urb(pdata
->urb
);
337 cancel_delayed_work(&pdata
->work
);
338 backlight_device_unregister(pdata
->bd
);
339 usb_buffer_free(pdata
->udev
, ACD_URB_BUFFER_LEN
,
340 pdata
->urbdata
, pdata
->urb
->transfer_dma
);
341 usb_free_urb(pdata
->urb
);
342 kfree(pdata
->msgdata
);
346 printk(KERN_INFO
"appledisplay: Apple Cinema Display disconnected\n");
349 static struct usb_driver appledisplay_driver
= {
350 .name
= "appledisplay",
351 .probe
= appledisplay_probe
,
352 .disconnect
= appledisplay_disconnect
,
353 .id_table
= appledisplay_table
,
356 static int __init
appledisplay_init(void)
358 wq
= create_singlethread_workqueue("appledisplay");
360 printk(KERN_ERR
"appledisplay: Could not create work queue\n");
364 return usb_register(&appledisplay_driver
);
367 static void __exit
appledisplay_exit(void)
370 destroy_workqueue(wq
);
371 usb_deregister(&appledisplay_driver
);
374 MODULE_AUTHOR("Michael Hanselmann");
375 MODULE_DESCRIPTION("Apple Cinema Display driver");
376 MODULE_LICENSE("GPL");
378 module_init(appledisplay_init
);
379 module_exit(appledisplay_exit
);