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