1 /* 2 * A driver for the Griffin Technology, Inc. "PowerMate" USB controller dial. 3 * 4 * v1.1, (c)2002 William R Sowerbutts <will@sowerbutts.com> 5 * 6 * This device is a anodised aluminium knob which connects over USB. It can measure 7 * clockwise and anticlockwise rotation. The dial also acts as a pushbutton with 8 * a spring for automatic release. The base contains a pair of LEDs which illuminate 9 * the translucent base. It rotates without limit and reports its relative rotation 10 * back to the host when polled by the USB controller. 11 * 12 * Testing with the knob I have has shown that it measures approximately 94 "clicks" 13 * for one full rotation. Testing with my High Speed Rotation Actuator (ok, it was 14 * a variable speed cordless electric drill) has shown that the device can measure 15 * speeds of up to 7 clicks either clockwise or anticlockwise between pollings from 16 * the host. If it counts more than 7 clicks before it is polled, it will wrap back 17 * to zero and start counting again. This was at quite high speed, however, almost 18 * certainly faster than the human hand could turn it. Griffin say that it loses a 19 * pulse or two on a direction change; the granularity is so fine that I never 20 * noticed this in practice. 21 * 22 * The device's microcontroller can be programmed to set the LED to either a constant 23 * intensity, or to a rhythmic pulsing. Several patterns and speeds are available. 24 * 25 * Griffin were very happy to provide documentation and free hardware for development. 26 * 27 * Some userspace tools are available on the web: http://sowerbutts.com/powermate/ 28 * 29 */ 30 31 #include <linux/kernel.h> 32 #include <linux/slab.h> 33 #include <linux/module.h> 34 #include <linux/init.h> 35 #include <linux/spinlock.h> 36 #include <linux/usb/input.h> 37 38 #define POWERMATE_VENDOR 0x077d /* Griffin Technology, Inc. */ 39 #define POWERMATE_PRODUCT_NEW 0x0410 /* Griffin PowerMate */ 40 #define POWERMATE_PRODUCT_OLD 0x04AA /* Griffin soundKnob */ 41 42 #define CONTOUR_VENDOR 0x05f3 /* Contour Design, Inc. */ 43 #define CONTOUR_JOG 0x0240 /* Jog and Shuttle */ 44 45 /* these are the command codes we send to the device */ 46 #define SET_STATIC_BRIGHTNESS 0x01 47 #define SET_PULSE_ASLEEP 0x02 48 #define SET_PULSE_AWAKE 0x03 49 #define SET_PULSE_MODE 0x04 50 51 /* these refer to bits in the powermate_device's requires_update field. */ 52 #define UPDATE_STATIC_BRIGHTNESS (1<<0) 53 #define UPDATE_PULSE_ASLEEP (1<<1) 54 #define UPDATE_PULSE_AWAKE (1<<2) 55 #define UPDATE_PULSE_MODE (1<<3) 56 57 /* at least two versions of the hardware exist, with differing payload 58 sizes. the first three bytes always contain the "interesting" data in 59 the relevant format. */ 60 #define POWERMATE_PAYLOAD_SIZE_MAX 6 61 #define POWERMATE_PAYLOAD_SIZE_MIN 3 62 struct powermate_device { 63 signed char *data; 64 dma_addr_t data_dma; 65 struct urb *irq, *config; 66 struct usb_ctrlrequest *configcr; 67 struct usb_device *udev; 68 struct input_dev *input; 69 spinlock_t lock; 70 int static_brightness; 71 int pulse_speed; 72 int pulse_table; 73 int pulse_asleep; 74 int pulse_awake; 75 int requires_update; // physical settings which are out of sync 76 char phys[64]; 77 }; 78 79 static char pm_name_powermate[] = "Griffin PowerMate"; 80 static char pm_name_soundknob[] = "Griffin SoundKnob"; 81 82 static void powermate_config_complete(struct urb *urb); 83 84 /* Callback for data arriving from the PowerMate over the USB interrupt pipe */ 85 static void powermate_irq(struct urb *urb) 86 { 87 struct powermate_device *pm = urb->context; 88 int retval; 89 90 switch (urb->status) { 91 case 0: 92 /* success */ 93 break; 94 case -ECONNRESET: 95 case -ENOENT: 96 case -ESHUTDOWN: 97 /* this urb is terminated, clean up */ 98 dbg("%s - urb shutting down with status: %d", __func__, urb->status); 99 return; 100 default: 101 dbg("%s - nonzero urb status received: %d", __func__, urb->status); 102 goto exit; 103 } 104 105 /* handle updates to device state */ 106 input_report_key(pm->input, BTN_0, pm->data[0] & 0x01); 107 input_report_rel(pm->input, REL_DIAL, pm->data[1]); 108 input_sync(pm->input); 109 110 exit: 111 retval = usb_submit_urb (urb, GFP_ATOMIC); 112 if (retval) 113 err ("%s - usb_submit_urb failed with result %d", 114 __func__, retval); 115 } 116 117 /* Decide if we need to issue a control message and do so. Must be called with pm->lock taken */ 118 static void powermate_sync_state(struct powermate_device *pm) 119 { 120 if (pm->requires_update == 0) 121 return; /* no updates are required */ 122 if (pm->config->status == -EINPROGRESS) 123 return; /* an update is already in progress; it'll issue this update when it completes */ 124 125 if (pm->requires_update & UPDATE_PULSE_ASLEEP){ 126 pm->configcr->wValue = cpu_to_le16( SET_PULSE_ASLEEP ); 127 pm->configcr->wIndex = cpu_to_le16( pm->pulse_asleep ? 1 : 0 ); 128 pm->requires_update &= ~UPDATE_PULSE_ASLEEP; 129 }else if (pm->requires_update & UPDATE_PULSE_AWAKE){ 130 pm->configcr->wValue = cpu_to_le16( SET_PULSE_AWAKE ); 131 pm->configcr->wIndex = cpu_to_le16( pm->pulse_awake ? 1 : 0 ); 132 pm->requires_update &= ~UPDATE_PULSE_AWAKE; 133 }else if (pm->requires_update & UPDATE_PULSE_MODE){ 134 int op, arg; 135 /* the powermate takes an operation and an argument for its pulse algorithm. 136 the operation can be: 137 0: divide the speed 138 1: pulse at normal speed 139 2: multiply the speed 140 the argument only has an effect for operations 0 and 2, and ranges between 141 1 (least effect) to 255 (maximum effect). 142 143 thus, several states are equivalent and are coalesced into one state. 144 145 we map this onto a range from 0 to 510, with: 146 0 -- 254 -- use divide (0 = slowest) 147 255 -- use normal speed 148 256 -- 510 -- use multiple (510 = fastest). 149 150 Only values of 'arg' quite close to 255 are particularly useful/spectacular. 151 */ 152 if (pm->pulse_speed < 255) { 153 op = 0; // divide 154 arg = 255 - pm->pulse_speed; 155 } else if (pm->pulse_speed > 255) { 156 op = 2; // multiply 157 arg = pm->pulse_speed - 255; 158 } else { 159 op = 1; // normal speed 160 arg = 0; // can be any value 161 } 162 pm->configcr->wValue = cpu_to_le16( (pm->pulse_table << 8) | SET_PULSE_MODE ); 163 pm->configcr->wIndex = cpu_to_le16( (arg << 8) | op ); 164 pm->requires_update &= ~UPDATE_PULSE_MODE; 165 } else if (pm->requires_update & UPDATE_STATIC_BRIGHTNESS) { 166 pm->configcr->wValue = cpu_to_le16( SET_STATIC_BRIGHTNESS ); 167 pm->configcr->wIndex = cpu_to_le16( pm->static_brightness ); 168 pm->requires_update &= ~UPDATE_STATIC_BRIGHTNESS; 169 } else { 170 printk(KERN_ERR "powermate: unknown update required"); 171 pm->requires_update = 0; /* fudge the bug */ 172 return; 173 } 174 175 /* printk("powermate: %04x %04x\n", pm->configcr->wValue, pm->configcr->wIndex); */ 176 177 pm->configcr->bRequestType = 0x41; /* vendor request */ 178 pm->configcr->bRequest = 0x01; 179 pm->configcr->wLength = 0; 180 181 usb_fill_control_urb(pm->config, pm->udev, usb_sndctrlpipe(pm->udev, 0), 182 (void *) pm->configcr, NULL, 0, 183 powermate_config_complete, pm); 184 185 if (usb_submit_urb(pm->config, GFP_ATOMIC)) 186 printk(KERN_ERR "powermate: usb_submit_urb(config) failed"); 187 } 188 189 /* Called when our asynchronous control message completes. We may need to issue another immediately */ 190 static void powermate_config_complete(struct urb *urb) 191 { 192 struct powermate_device *pm = urb->context; 193 unsigned long flags; 194 195 if (urb->status) 196 printk(KERN_ERR "powermate: config urb returned %d\n", urb->status); 197 198 spin_lock_irqsave(&pm->lock, flags); 199 powermate_sync_state(pm); 200 spin_unlock_irqrestore(&pm->lock, flags); 201 } 202 203 /* Set the LED up as described and begin the sync with the hardware if required */ 204 static void powermate_pulse_led(struct powermate_device *pm, int static_brightness, int pulse_speed, 205 int pulse_table, int pulse_asleep, int pulse_awake) 206 { 207 unsigned long flags; 208 209 if (pulse_speed < 0) 210 pulse_speed = 0; 211 if (pulse_table < 0) 212 pulse_table = 0; 213 if (pulse_speed > 510) 214 pulse_speed = 510; 215 if (pulse_table > 2) 216 pulse_table = 2; 217 218 pulse_asleep = !!pulse_asleep; 219 pulse_awake = !!pulse_awake; 220 221 222 spin_lock_irqsave(&pm->lock, flags); 223 224 /* mark state updates which are required */ 225 if (static_brightness != pm->static_brightness) { 226 pm->static_brightness = static_brightness; 227 pm->requires_update |= UPDATE_STATIC_BRIGHTNESS; 228 } 229 if (pulse_asleep != pm->pulse_asleep) { 230 pm->pulse_asleep = pulse_asleep; 231 pm->requires_update |= (UPDATE_PULSE_ASLEEP | UPDATE_STATIC_BRIGHTNESS); 232 } 233 if (pulse_awake != pm->pulse_awake) { 234 pm->pulse_awake = pulse_awake; 235 pm->requires_update |= (UPDATE_PULSE_AWAKE | UPDATE_STATIC_BRIGHTNESS); 236 } 237 if (pulse_speed != pm->pulse_speed || pulse_table != pm->pulse_table) { 238 pm->pulse_speed = pulse_speed; 239 pm->pulse_table = pulse_table; 240 pm->requires_update |= UPDATE_PULSE_MODE; 241 } 242 243 powermate_sync_state(pm); 244 245 spin_unlock_irqrestore(&pm->lock, flags); 246 } 247 248 /* Callback from the Input layer when an event arrives from userspace to configure the LED */ 249 static int powermate_input_event(struct input_dev *dev, unsigned int type, unsigned int code, int _value) 250 { 251 unsigned int command = (unsigned int)_value; 252 struct powermate_device *pm = input_get_drvdata(dev); 253 254 if (type == EV_MSC && code == MSC_PULSELED){ 255 /* 256 bits 0- 7: 8 bits: LED brightness 257 bits 8-16: 9 bits: pulsing speed modifier (0 ... 510); 0-254 = slower, 255 = standard, 256-510 = faster. 258 bits 17-18: 2 bits: pulse table (0, 1, 2 valid) 259 bit 19: 1 bit : pulse whilst asleep? 260 bit 20: 1 bit : pulse constantly? 261 */ 262 int static_brightness = command & 0xFF; // bits 0-7 263 int pulse_speed = (command >> 8) & 0x1FF; // bits 8-16 264 int pulse_table = (command >> 17) & 0x3; // bits 17-18 265 int pulse_asleep = (command >> 19) & 0x1; // bit 19 266 int pulse_awake = (command >> 20) & 0x1; // bit 20 267 268 powermate_pulse_led(pm, static_brightness, pulse_speed, pulse_table, pulse_asleep, pulse_awake); 269 } 270 271 return 0; 272 } 273 274 static int powermate_alloc_buffers(struct usb_device *udev, struct powermate_device *pm) 275 { 276 pm->data = usb_alloc_coherent(udev, POWERMATE_PAYLOAD_SIZE_MAX, 277 GFP_ATOMIC, &pm->data_dma); 278 if (!pm->data) 279 return -1; 280 281 pm->configcr = kmalloc(sizeof(*(pm->configcr)), GFP_KERNEL); 282 if (!pm->configcr) 283 return -ENOMEM; 284 285 return 0; 286 } 287 288 static void powermate_free_buffers(struct usb_device *udev, struct powermate_device *pm) 289 { 290 usb_free_coherent(udev, POWERMATE_PAYLOAD_SIZE_MAX, 291 pm->data, pm->data_dma); 292 kfree(pm->configcr); 293 } 294 295 /* Called whenever a USB device matching one in our supported devices table is connected */ 296 static int powermate_probe(struct usb_interface *intf, const struct usb_device_id *id) 297 { 298 struct usb_device *udev = interface_to_usbdev (intf); 299 struct usb_host_interface *interface; 300 struct usb_endpoint_descriptor *endpoint; 301 struct powermate_device *pm; 302 struct input_dev *input_dev; 303 int pipe, maxp; 304 int error = -ENOMEM; 305 306 interface = intf->cur_altsetting; 307 endpoint = &interface->endpoint[0].desc; 308 if (!usb_endpoint_is_int_in(endpoint)) 309 return -EIO; 310 311 usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 312 0x0a, USB_TYPE_CLASS | USB_RECIP_INTERFACE, 313 0, interface->desc.bInterfaceNumber, NULL, 0, 314 USB_CTRL_SET_TIMEOUT); 315 316 pm = kzalloc(sizeof(struct powermate_device), GFP_KERNEL); 317 input_dev = input_allocate_device(); 318 if (!pm || !input_dev) 319 goto fail1; 320 321 if (powermate_alloc_buffers(udev, pm)) 322 goto fail2; 323 324 pm->irq = usb_alloc_urb(0, GFP_KERNEL); 325 if (!pm->irq) 326 goto fail2; 327 328 pm->config = usb_alloc_urb(0, GFP_KERNEL); 329 if (!pm->config) 330 goto fail3; 331 332 pm->udev = udev; 333 pm->input = input_dev; 334 335 usb_make_path(udev, pm->phys, sizeof(pm->phys)); 336 strlcat(pm->phys, "/input0", sizeof(pm->phys)); 337 338 spin_lock_init(&pm->lock); 339 340 switch (le16_to_cpu(udev->descriptor.idProduct)) { 341 case POWERMATE_PRODUCT_NEW: 342 input_dev->name = pm_name_powermate; 343 break; 344 case POWERMATE_PRODUCT_OLD: 345 input_dev->name = pm_name_soundknob; 346 break; 347 default: 348 input_dev->name = pm_name_soundknob; 349 printk(KERN_WARNING "powermate: unknown product id %04x\n", 350 le16_to_cpu(udev->descriptor.idProduct)); 351 } 352 353 input_dev->phys = pm->phys; 354 usb_to_input_id(udev, &input_dev->id); 355 input_dev->dev.parent = &intf->dev; 356 357 input_set_drvdata(input_dev, pm); 358 359 input_dev->event = powermate_input_event; 360 361 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) | 362 BIT_MASK(EV_MSC); 363 input_dev->keybit[BIT_WORD(BTN_0)] = BIT_MASK(BTN_0); 364 input_dev->relbit[BIT_WORD(REL_DIAL)] = BIT_MASK(REL_DIAL); 365 input_dev->mscbit[BIT_WORD(MSC_PULSELED)] = BIT_MASK(MSC_PULSELED); 366 367 /* get a handle to the interrupt data pipe */ 368 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress); 369 maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe)); 370 371 if (maxp < POWERMATE_PAYLOAD_SIZE_MIN || maxp > POWERMATE_PAYLOAD_SIZE_MAX) { 372 printk(KERN_WARNING "powermate: Expected payload of %d--%d bytes, found %d bytes!\n", 373 POWERMATE_PAYLOAD_SIZE_MIN, POWERMATE_PAYLOAD_SIZE_MAX, maxp); 374 maxp = POWERMATE_PAYLOAD_SIZE_MAX; 375 } 376 377 usb_fill_int_urb(pm->irq, udev, pipe, pm->data, 378 maxp, powermate_irq, 379 pm, endpoint->bInterval); 380 pm->irq->transfer_dma = pm->data_dma; 381 pm->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 382 383 /* register our interrupt URB with the USB system */ 384 if (usb_submit_urb(pm->irq, GFP_KERNEL)) { 385 error = -EIO; 386 goto fail4; 387 } 388 389 error = input_register_device(pm->input); 390 if (error) 391 goto fail5; 392 393 394 /* force an update of everything */ 395 pm->requires_update = UPDATE_PULSE_ASLEEP | UPDATE_PULSE_AWAKE | UPDATE_PULSE_MODE | UPDATE_STATIC_BRIGHTNESS; 396 powermate_pulse_led(pm, 0x80, 255, 0, 1, 0); // set default pulse parameters 397 398 usb_set_intfdata(intf, pm); 399 return 0; 400 401 fail5: usb_kill_urb(pm->irq); 402 fail4: usb_free_urb(pm->config); 403 fail3: usb_free_urb(pm->irq); 404 fail2: powermate_free_buffers(udev, pm); 405 fail1: input_free_device(input_dev); 406 kfree(pm); 407 return error; 408 } 409 410 /* Called when a USB device we've accepted ownership of is removed */ 411 static void powermate_disconnect(struct usb_interface *intf) 412 { 413 struct powermate_device *pm = usb_get_intfdata (intf); 414 415 usb_set_intfdata(intf, NULL); 416 if (pm) { 417 pm->requires_update = 0; 418 usb_kill_urb(pm->irq); 419 input_unregister_device(pm->input); 420 usb_free_urb(pm->irq); 421 usb_free_urb(pm->config); 422 powermate_free_buffers(interface_to_usbdev(intf), pm); 423 424 kfree(pm); 425 } 426 } 427 428 static struct usb_device_id powermate_devices [] = { 429 { USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_NEW) }, 430 { USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_OLD) }, 431 { USB_DEVICE(CONTOUR_VENDOR, CONTOUR_JOG) }, 432 { } /* Terminating entry */ 433 }; 434 435 MODULE_DEVICE_TABLE (usb, powermate_devices); 436 437 static struct usb_driver powermate_driver = { 438 .name = "powermate", 439 .probe = powermate_probe, 440 .disconnect = powermate_disconnect, 441 .id_table = powermate_devices, 442 }; 443 444 static int __init powermate_init(void) 445 { 446 return usb_register(&powermate_driver); 447 } 448 449 static void __exit powermate_cleanup(void) 450 { 451 usb_deregister(&powermate_driver); 452 } 453 454 module_init(powermate_init); 455 module_exit(powermate_cleanup); 456 457 MODULE_AUTHOR( "William R Sowerbutts" ); 458 MODULE_DESCRIPTION( "Griffin Technology, Inc PowerMate driver" ); 459 MODULE_LICENSE("GPL"); 460