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