Linux Audio

Check our new training course

Loading...
v4.10.11
  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 <linux/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 */
 61static const struct usb_device_id appledisplay_table[] = {
 62	{ APPLEDISPLAY_DEVICE(0x9218) },
 63	{ APPLEDISPLAY_DEVICE(0x9219) },
 64	{ APPLEDISPLAY_DEVICE(0x921c) },
 65	{ APPLEDISPLAY_DEVICE(0x921d) },
 66	{ APPLEDISPLAY_DEVICE(0x9236) },
 67
 68	/* Terminating entry */
 69	{ }
 70};
 71MODULE_DEVICE_TABLE(usb, appledisplay_table);
 72
 73/* Structure to hold all of our device specific stuff */
 74struct appledisplay {
 75	struct usb_device *udev;	/* usb device */
 76	struct urb *urb;		/* usb request block */
 77	struct backlight_device *bd;	/* backlight device */
 78	u8 *urbdata;			/* interrupt URB data buffer */
 79	u8 *msgdata;			/* control message data buffer */
 80
 81	struct delayed_work work;
 82	int button_pressed;
 83	spinlock_t lock;
 84	struct mutex sysfslock;		/* concurrent read and write */
 85};
 86
 87static atomic_t count_displays = ATOMIC_INIT(0);
 
 88
 89static void appledisplay_complete(struct urb *urb)
 90{
 91	struct appledisplay *pdata = urb->context;
 92	struct device *dev = &pdata->udev->dev;
 93	unsigned long flags;
 94	int status = urb->status;
 95	int retval;
 96
 97	switch (status) {
 98	case 0:
 99		/* success */
100		break;
101	case -EOVERFLOW:
102		dev_err(dev,
103			"OVERFLOW with data length %d, actual length is %d\n",
104			ACD_URB_BUFFER_LEN, pdata->urb->actual_length);
105	case -ECONNRESET:
106	case -ENOENT:
107	case -ESHUTDOWN:
108		/* This urb is terminated, clean up */
109		dev_dbg(dev, "%s - urb shuttingdown with status: %d\n",
110			__func__, status);
111		return;
112	default:
113		dev_dbg(dev, "%s - nonzero urb status received: %d\n",
114			__func__, status);
115		goto exit;
116	}
117
118	spin_lock_irqsave(&pdata->lock, flags);
119
120	switch(pdata->urbdata[1]) {
121	case ACD_BTN_BRIGHT_UP:
122	case ACD_BTN_BRIGHT_DOWN:
123		pdata->button_pressed = 1;
124		schedule_delayed_work(&pdata->work, 0);
125		break;
126	case ACD_BTN_NONE:
127	default:
128		pdata->button_pressed = 0;
129		break;
130	}
131
132	spin_unlock_irqrestore(&pdata->lock, flags);
133
134exit:
135	retval = usb_submit_urb(pdata->urb, GFP_ATOMIC);
136	if (retval) {
137		dev_err(dev, "%s - usb_submit_urb failed with result %d\n",
138			__func__, retval);
139	}
140}
141
142static int appledisplay_bl_update_status(struct backlight_device *bd)
143{
144	struct appledisplay *pdata = bl_get_data(bd);
145	int retval;
146
147	mutex_lock(&pdata->sysfslock);
148	pdata->msgdata[0] = 0x10;
149	pdata->msgdata[1] = bd->props.brightness;
150
151	retval = usb_control_msg(
152		pdata->udev,
153		usb_sndctrlpipe(pdata->udev, 0),
154		USB_REQ_SET_REPORT,
155		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
156		ACD_USB_BRIGHTNESS,
157		0,
158		pdata->msgdata, 2,
159		ACD_USB_TIMEOUT);
160	mutex_unlock(&pdata->sysfslock);
161	
162	return retval;
163}
164
165static int appledisplay_bl_get_brightness(struct backlight_device *bd)
166{
167	struct appledisplay *pdata = bl_get_data(bd);
168	int retval, brightness;
169
170	mutex_lock(&pdata->sysfslock);
171	retval = usb_control_msg(
172		pdata->udev,
173		usb_rcvctrlpipe(pdata->udev, 0),
174		USB_REQ_GET_REPORT,
175		USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
176		ACD_USB_BRIGHTNESS,
177		0,
178		pdata->msgdata, 2,
179		ACD_USB_TIMEOUT);
180	brightness = pdata->msgdata[1];
181	mutex_unlock(&pdata->sysfslock);
182
183	if (retval < 0)
184		return retval;
185	else
186		return brightness;
187}
188
189static const struct backlight_ops appledisplay_bl_data = {
190	.get_brightness	= appledisplay_bl_get_brightness,
191	.update_status	= appledisplay_bl_update_status,
192};
193
194static void appledisplay_work(struct work_struct *work)
195{
196	struct appledisplay *pdata =
197		container_of(work, struct appledisplay, work.work);
198	int retval;
199
200	retval = appledisplay_bl_get_brightness(pdata->bd);
201	if (retval >= 0)
202		pdata->bd->props.brightness = retval;
203
204	/* Poll again in about 125ms if there's still a button pressed */
205	if (pdata->button_pressed)
206		schedule_delayed_work(&pdata->work, HZ / 8);
207}
208
209static int appledisplay_probe(struct usb_interface *iface,
210	const struct usb_device_id *id)
211{
212	struct backlight_properties props;
213	struct appledisplay *pdata;
214	struct usb_device *udev = interface_to_usbdev(iface);
215	struct usb_host_interface *iface_desc;
216	struct usb_endpoint_descriptor *endpoint;
217	int int_in_endpointAddr = 0;
218	int i, retval = -ENOMEM, brightness;
219	char bl_name[20];
220
221	/* set up the endpoint information */
222	/* use only the first interrupt-in endpoint */
223	iface_desc = iface->cur_altsetting;
224	for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
225		endpoint = &iface_desc->endpoint[i].desc;
226		if (!int_in_endpointAddr && usb_endpoint_is_int_in(endpoint)) {
227			/* we found an interrupt in endpoint */
228			int_in_endpointAddr = endpoint->bEndpointAddress;
229			break;
230		}
231	}
232	if (!int_in_endpointAddr) {
233		dev_err(&iface->dev, "Could not find int-in endpoint\n");
234		return -EIO;
235	}
236
237	/* allocate memory for our device state and initialize it */
238	pdata = kzalloc(sizeof(struct appledisplay), GFP_KERNEL);
239	if (!pdata) {
240		retval = -ENOMEM;
 
241		goto error;
242	}
243
244	pdata->udev = udev;
245
246	spin_lock_init(&pdata->lock);
247	INIT_DELAYED_WORK(&pdata->work, appledisplay_work);
248	mutex_init(&pdata->sysfslock);
249
250	/* Allocate buffer for control messages */
251	pdata->msgdata = kmalloc(ACD_MSG_BUFFER_LEN, GFP_KERNEL);
252	if (!pdata->msgdata) {
253		retval = -ENOMEM;
 
 
254		goto error;
255	}
256
257	/* Allocate interrupt URB */
258	pdata->urb = usb_alloc_urb(0, GFP_KERNEL);
259	if (!pdata->urb) {
260		retval = -ENOMEM;
 
261		goto error;
262	}
263
264	/* Allocate buffer for interrupt data */
265	pdata->urbdata = usb_alloc_coherent(pdata->udev, ACD_URB_BUFFER_LEN,
266		GFP_KERNEL, &pdata->urb->transfer_dma);
267	if (!pdata->urbdata) {
268		retval = -ENOMEM;
269		dev_err(&iface->dev, "Allocating URB buffer failed\n");
270		goto error;
271	}
272
273	/* Configure interrupt URB */
274	usb_fill_int_urb(pdata->urb, udev,
275		usb_rcvintpipe(udev, int_in_endpointAddr),
276		pdata->urbdata, ACD_URB_BUFFER_LEN, appledisplay_complete,
277		pdata, 1);
278	if (usb_submit_urb(pdata->urb, GFP_KERNEL)) {
279		retval = -EIO;
280		dev_err(&iface->dev, "Submitting URB failed\n");
281		goto error;
282	}
283
284	/* Register backlight device */
285	snprintf(bl_name, sizeof(bl_name), "appledisplay%d",
286		atomic_inc_return(&count_displays) - 1);
287	memset(&props, 0, sizeof(struct backlight_properties));
288	props.type = BACKLIGHT_RAW;
289	props.max_brightness = 0xff;
290	pdata->bd = backlight_device_register(bl_name, NULL, pdata,
291					      &appledisplay_bl_data, &props);
292	if (IS_ERR(pdata->bd)) {
293		dev_err(&iface->dev, "Backlight registration failed\n");
294		retval = PTR_ERR(pdata->bd);
295		goto error;
296	}
297
298	/* Try to get brightness */
299	brightness = appledisplay_bl_get_brightness(pdata->bd);
300
301	if (brightness < 0) {
302		retval = brightness;
303		dev_err(&iface->dev,
304			"Error while getting initial brightness: %d\n", retval);
305		goto error;
306	}
307
308	/* Set brightness in backlight device */
309	pdata->bd->props.brightness = brightness;
310
311	/* save our data pointer in the interface device */
312	usb_set_intfdata(iface, pdata);
313
314	printk(KERN_INFO "appledisplay: Apple Cinema Display connected\n");
315
316	return 0;
317
318error:
319	if (pdata) {
320		if (pdata->urb) {
321			usb_kill_urb(pdata->urb);
322			if (pdata->urbdata)
323				usb_free_coherent(pdata->udev, ACD_URB_BUFFER_LEN,
324					pdata->urbdata, pdata->urb->transfer_dma);
325			usb_free_urb(pdata->urb);
326		}
327		if (!IS_ERR(pdata->bd))
328			backlight_device_unregister(pdata->bd);
329		kfree(pdata->msgdata);
330	}
331	usb_set_intfdata(iface, NULL);
332	kfree(pdata);
333	return retval;
334}
335
336static void appledisplay_disconnect(struct usb_interface *iface)
337{
338	struct appledisplay *pdata = usb_get_intfdata(iface);
339
340	if (pdata) {
341		usb_kill_urb(pdata->urb);
342		cancel_delayed_work_sync(&pdata->work);
343		backlight_device_unregister(pdata->bd);
344		usb_free_coherent(pdata->udev, ACD_URB_BUFFER_LEN,
345			pdata->urbdata, pdata->urb->transfer_dma);
346		usb_free_urb(pdata->urb);
347		kfree(pdata->msgdata);
348		kfree(pdata);
349	}
350
351	printk(KERN_INFO "appledisplay: Apple Cinema Display disconnected\n");
352}
353
354static struct usb_driver appledisplay_driver = {
355	.name		= "appledisplay",
356	.probe		= appledisplay_probe,
357	.disconnect	= appledisplay_disconnect,
358	.id_table	= appledisplay_table,
359};
360
361static int __init appledisplay_init(void)
362{
 
 
 
 
 
 
363	return usb_register(&appledisplay_driver);
364}
365
366static void __exit appledisplay_exit(void)
367{
 
 
368	usb_deregister(&appledisplay_driver);
369}
370
371MODULE_AUTHOR("Michael Hanselmann");
372MODULE_DESCRIPTION("Apple Cinema Display driver");
373MODULE_LICENSE("GPL");
374
375module_init(appledisplay_init);
376module_exit(appledisplay_exit);
v3.15
  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 <linux/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 */
 61static const struct usb_device_id appledisplay_table[] = {
 62	{ APPLEDISPLAY_DEVICE(0x9218) },
 63	{ APPLEDISPLAY_DEVICE(0x9219) },
 64	{ APPLEDISPLAY_DEVICE(0x921c) },
 65	{ APPLEDISPLAY_DEVICE(0x921d) },
 66	{ APPLEDISPLAY_DEVICE(0x9236) },
 67
 68	/* Terminating entry */
 69	{ }
 70};
 71MODULE_DEVICE_TABLE(usb, appledisplay_table);
 72
 73/* Structure to hold all of our device specific stuff */
 74struct appledisplay {
 75	struct usb_device *udev;	/* usb device */
 76	struct urb *urb;		/* usb request block */
 77	struct backlight_device *bd;	/* backlight device */
 78	u8 *urbdata;			/* interrupt URB data buffer */
 79	u8 *msgdata;			/* control message data buffer */
 80
 81	struct delayed_work work;
 82	int button_pressed;
 83	spinlock_t lock;
 
 84};
 85
 86static atomic_t count_displays = ATOMIC_INIT(0);
 87static struct workqueue_struct *wq;
 88
 89static void appledisplay_complete(struct urb *urb)
 90{
 91	struct appledisplay *pdata = urb->context;
 92	struct device *dev = &pdata->udev->dev;
 93	unsigned long flags;
 94	int status = urb->status;
 95	int retval;
 96
 97	switch (status) {
 98	case 0:
 99		/* success */
100		break;
101	case -EOVERFLOW:
102		dev_err(dev,
103			"OVERFLOW with data length %d, actual length is %d\n",
104			ACD_URB_BUFFER_LEN, pdata->urb->actual_length);
105	case -ECONNRESET:
106	case -ENOENT:
107	case -ESHUTDOWN:
108		/* This urb is terminated, clean up */
109		dev_dbg(dev, "%s - urb shuttingdown with status: %d\n",
110			__func__, status);
111		return;
112	default:
113		dev_dbg(dev, "%s - nonzero urb status received: %d/n",
114			__func__, status);
115		goto exit;
116	}
117
118	spin_lock_irqsave(&pdata->lock, flags);
119
120	switch(pdata->urbdata[1]) {
121	case ACD_BTN_BRIGHT_UP:
122	case ACD_BTN_BRIGHT_DOWN:
123		pdata->button_pressed = 1;
124		queue_delayed_work(wq, &pdata->work, 0);
125		break;
126	case ACD_BTN_NONE:
127	default:
128		pdata->button_pressed = 0;
129		break;
130	}
131
132	spin_unlock_irqrestore(&pdata->lock, flags);
133
134exit:
135	retval = usb_submit_urb(pdata->urb, GFP_ATOMIC);
136	if (retval) {
137		dev_err(dev, "%s - usb_submit_urb failed with result %d\n",
138			__func__, retval);
139	}
140}
141
142static int appledisplay_bl_update_status(struct backlight_device *bd)
143{
144	struct appledisplay *pdata = bl_get_data(bd);
145	int retval;
146
 
147	pdata->msgdata[0] = 0x10;
148	pdata->msgdata[1] = bd->props.brightness;
149
150	retval = usb_control_msg(
151		pdata->udev,
152		usb_sndctrlpipe(pdata->udev, 0),
153		USB_REQ_SET_REPORT,
154		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
155		ACD_USB_BRIGHTNESS,
156		0,
157		pdata->msgdata, 2,
158		ACD_USB_TIMEOUT);
159
 
160	return retval;
161}
162
163static int appledisplay_bl_get_brightness(struct backlight_device *bd)
164{
165	struct appledisplay *pdata = bl_get_data(bd);
166	int retval;
167
 
168	retval = usb_control_msg(
169		pdata->udev,
170		usb_rcvctrlpipe(pdata->udev, 0),
171		USB_REQ_GET_REPORT,
172		USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
173		ACD_USB_BRIGHTNESS,
174		0,
175		pdata->msgdata, 2,
176		ACD_USB_TIMEOUT);
 
 
177
178	if (retval < 0)
179		return retval;
180	else
181		return pdata->msgdata[1];
182}
183
184static const struct backlight_ops appledisplay_bl_data = {
185	.get_brightness	= appledisplay_bl_get_brightness,
186	.update_status	= appledisplay_bl_update_status,
187};
188
189static void appledisplay_work(struct work_struct *work)
190{
191	struct appledisplay *pdata =
192		container_of(work, struct appledisplay, work.work);
193	int retval;
194
195	retval = appledisplay_bl_get_brightness(pdata->bd);
196	if (retval >= 0)
197		pdata->bd->props.brightness = retval;
198
199	/* Poll again in about 125ms if there's still a button pressed */
200	if (pdata->button_pressed)
201		schedule_delayed_work(&pdata->work, HZ / 8);
202}
203
204static int appledisplay_probe(struct usb_interface *iface,
205	const struct usb_device_id *id)
206{
207	struct backlight_properties props;
208	struct appledisplay *pdata;
209	struct usb_device *udev = interface_to_usbdev(iface);
210	struct usb_host_interface *iface_desc;
211	struct usb_endpoint_descriptor *endpoint;
212	int int_in_endpointAddr = 0;
213	int i, retval = -ENOMEM, brightness;
214	char bl_name[20];
215
216	/* set up the endpoint information */
217	/* use only the first interrupt-in endpoint */
218	iface_desc = iface->cur_altsetting;
219	for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
220		endpoint = &iface_desc->endpoint[i].desc;
221		if (!int_in_endpointAddr && usb_endpoint_is_int_in(endpoint)) {
222			/* we found an interrupt in endpoint */
223			int_in_endpointAddr = endpoint->bEndpointAddress;
224			break;
225		}
226	}
227	if (!int_in_endpointAddr) {
228		dev_err(&iface->dev, "Could not find int-in endpoint\n");
229		return -EIO;
230	}
231
232	/* allocate memory for our device state and initialize it */
233	pdata = kzalloc(sizeof(struct appledisplay), GFP_KERNEL);
234	if (!pdata) {
235		retval = -ENOMEM;
236		dev_err(&iface->dev, "Out of memory\n");
237		goto error;
238	}
239
240	pdata->udev = udev;
241
242	spin_lock_init(&pdata->lock);
243	INIT_DELAYED_WORK(&pdata->work, appledisplay_work);
 
244
245	/* Allocate buffer for control messages */
246	pdata->msgdata = kmalloc(ACD_MSG_BUFFER_LEN, GFP_KERNEL);
247	if (!pdata->msgdata) {
248		retval = -ENOMEM;
249		dev_err(&iface->dev,
250			"Allocating buffer for control messages failed\n");
251		goto error;
252	}
253
254	/* Allocate interrupt URB */
255	pdata->urb = usb_alloc_urb(0, GFP_KERNEL);
256	if (!pdata->urb) {
257		retval = -ENOMEM;
258		dev_err(&iface->dev, "Allocating URB failed\n");
259		goto error;
260	}
261
262	/* Allocate buffer for interrupt data */
263	pdata->urbdata = usb_alloc_coherent(pdata->udev, ACD_URB_BUFFER_LEN,
264		GFP_KERNEL, &pdata->urb->transfer_dma);
265	if (!pdata->urbdata) {
266		retval = -ENOMEM;
267		dev_err(&iface->dev, "Allocating URB buffer failed\n");
268		goto error;
269	}
270
271	/* Configure interrupt URB */
272	usb_fill_int_urb(pdata->urb, udev,
273		usb_rcvintpipe(udev, int_in_endpointAddr),
274		pdata->urbdata, ACD_URB_BUFFER_LEN, appledisplay_complete,
275		pdata, 1);
276	if (usb_submit_urb(pdata->urb, GFP_KERNEL)) {
277		retval = -EIO;
278		dev_err(&iface->dev, "Submitting URB failed\n");
279		goto error;
280	}
281
282	/* Register backlight device */
283	snprintf(bl_name, sizeof(bl_name), "appledisplay%d",
284		atomic_inc_return(&count_displays) - 1);
285	memset(&props, 0, sizeof(struct backlight_properties));
286	props.type = BACKLIGHT_RAW;
287	props.max_brightness = 0xff;
288	pdata->bd = backlight_device_register(bl_name, NULL, pdata,
289					      &appledisplay_bl_data, &props);
290	if (IS_ERR(pdata->bd)) {
291		dev_err(&iface->dev, "Backlight registration failed\n");
292		retval = PTR_ERR(pdata->bd);
293		goto error;
294	}
295
296	/* Try to get brightness */
297	brightness = appledisplay_bl_get_brightness(pdata->bd);
298
299	if (brightness < 0) {
300		retval = brightness;
301		dev_err(&iface->dev,
302			"Error while getting initial brightness: %d\n", retval);
303		goto error;
304	}
305
306	/* Set brightness in backlight device */
307	pdata->bd->props.brightness = brightness;
308
309	/* save our data pointer in the interface device */
310	usb_set_intfdata(iface, pdata);
311
312	printk(KERN_INFO "appledisplay: Apple Cinema Display connected\n");
313
314	return 0;
315
316error:
317	if (pdata) {
318		if (pdata->urb) {
319			usb_kill_urb(pdata->urb);
320			if (pdata->urbdata)
321				usb_free_coherent(pdata->udev, ACD_URB_BUFFER_LEN,
322					pdata->urbdata, pdata->urb->transfer_dma);
323			usb_free_urb(pdata->urb);
324		}
325		if (pdata->bd && !IS_ERR(pdata->bd))
326			backlight_device_unregister(pdata->bd);
327		kfree(pdata->msgdata);
328	}
329	usb_set_intfdata(iface, NULL);
330	kfree(pdata);
331	return retval;
332}
333
334static void appledisplay_disconnect(struct usb_interface *iface)
335{
336	struct appledisplay *pdata = usb_get_intfdata(iface);
337
338	if (pdata) {
339		usb_kill_urb(pdata->urb);
340		cancel_delayed_work(&pdata->work);
341		backlight_device_unregister(pdata->bd);
342		usb_free_coherent(pdata->udev, ACD_URB_BUFFER_LEN,
343			pdata->urbdata, pdata->urb->transfer_dma);
344		usb_free_urb(pdata->urb);
345		kfree(pdata->msgdata);
346		kfree(pdata);
347	}
348
349	printk(KERN_INFO "appledisplay: Apple Cinema Display disconnected\n");
350}
351
352static struct usb_driver appledisplay_driver = {
353	.name		= "appledisplay",
354	.probe		= appledisplay_probe,
355	.disconnect	= appledisplay_disconnect,
356	.id_table	= appledisplay_table,
357};
358
359static int __init appledisplay_init(void)
360{
361	wq = create_singlethread_workqueue("appledisplay");
362	if (!wq) {
363		printk(KERN_ERR "appledisplay: Could not create work queue\n");
364		return -ENOMEM;
365	}
366
367	return usb_register(&appledisplay_driver);
368}
369
370static void __exit appledisplay_exit(void)
371{
372	flush_workqueue(wq);
373	destroy_workqueue(wq);
374	usb_deregister(&appledisplay_driver);
375}
376
377MODULE_AUTHOR("Michael Hanselmann");
378MODULE_DESCRIPTION("Apple Cinema Display driver");
379MODULE_LICENSE("GPL");
380
381module_init(appledisplay_init);
382module_exit(appledisplay_exit);