1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * A driver for the Griffin Technology, Inc. "PowerMate" USB controller dial. 4 * 5 * v1.1, (c)2002 William R Sowerbutts <will@sowerbutts.com> 6 * 7 * This device is a anodised aluminium knob which connects over USB. It can measure 8 * clockwise and anticlockwise rotation. The dial also acts as a pushbutton with 9 * a spring for automatic release. The base contains a pair of LEDs which illuminate 10 * the translucent base. It rotates without limit and reports its relative rotation 11 * back to the host when polled by the USB controller. 12 * 13 * Testing with the knob I have has shown that it measures approximately 94 "clicks" 14 * for one full rotation. Testing with my High Speed Rotation Actuator (ok, it was 15 * a variable speed cordless electric drill) has shown that the device can measure 16 * speeds of up to 7 clicks either clockwise or anticlockwise between pollings from 17 * the host. If it counts more than 7 clicks before it is polled, it will wrap back 18 * to zero and start counting again. This was at quite high speed, however, almost 19 * certainly faster than the human hand could turn it. Griffin say that it loses a 20 * pulse or two on a direction change; the granularity is so fine that I never 21 * noticed this in practice. 22 * 23 * The device's microcontroller can be programmed to set the LED to either a constant 24 * intensity, or to a rhythmic pulsing. Several patterns and speeds are available. 25 * 26 * Griffin were very happy to provide documentation and free hardware for development. 27 * 28 * Some userspace tools are available on the web: http://sowerbutts.com/powermate/ 29 * 30 */ 31 32 #include <linux/kernel.h> 33 #include <linux/slab.h> 34 #include <linux/module.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 usb_interface *intf; 69 struct input_dev *input; 70 spinlock_t lock; 71 int static_brightness; 72 int pulse_speed; 73 int pulse_table; 74 int pulse_asleep; 75 int pulse_awake; 76 int requires_update; // physical settings which are out of sync 77 char phys[64]; 78 }; 79 80 static char pm_name_powermate[] = "Griffin PowerMate"; 81 static char pm_name_soundknob[] = "Griffin SoundKnob"; 82 83 static void powermate_config_complete(struct urb *urb); 84 85 /* Callback for data arriving from the PowerMate over the USB interrupt pipe */ 86 static void powermate_irq(struct urb *urb) 87 { 88 struct powermate_device *pm = urb->context; 89 struct device *dev = &pm->intf->dev; 90 int retval; 91 92 switch (urb->status) { 93 case 0: 94 /* success */ 95 break; 96 case -ECONNRESET: 97 case -ENOENT: 98 case -ESHUTDOWN: 99 /* this urb is terminated, clean up */ 100 dev_dbg(dev, "%s - urb shutting down with status: %d\n", 101 __func__, urb->status); 102 return; 103 default: 104 dev_dbg(dev, "%s - nonzero urb status received: %d\n", 105 __func__, urb->status); 106 goto exit; 107 } 108 109 /* handle updates to device state */ 110 input_report_key(pm->input, BTN_0, pm->data[0] & 0x01); 111 input_report_rel(pm->input, REL_DIAL, pm->data[1]); 112 input_sync(pm->input); 113 114 exit: 115 retval = usb_submit_urb (urb, GFP_ATOMIC); 116 if (retval) 117 dev_err(dev, "%s - usb_submit_urb failed with result: %d\n", 118 __func__, retval); 119 } 120 121 /* Decide if we need to issue a control message and do so. Must be called with pm->lock taken */ 122 static void powermate_sync_state(struct powermate_device *pm) 123 { 124 if (pm->requires_update == 0) 125 return; /* no updates are required */ 126 if (pm->config->status == -EINPROGRESS) 127 return; /* an update is already in progress; it'll issue this update when it completes */ 128 129 if (pm->requires_update & UPDATE_PULSE_ASLEEP){ 130 pm->configcr->wValue = cpu_to_le16( SET_PULSE_ASLEEP ); 131 pm->configcr->wIndex = cpu_to_le16( pm->pulse_asleep ? 1 : 0 ); 132 pm->requires_update &= ~UPDATE_PULSE_ASLEEP; 133 }else if (pm->requires_update & UPDATE_PULSE_AWAKE){ 134 pm->configcr->wValue = cpu_to_le16( SET_PULSE_AWAKE ); 135 pm->configcr->wIndex = cpu_to_le16( pm->pulse_awake ? 1 : 0 ); 136 pm->requires_update &= ~UPDATE_PULSE_AWAKE; 137 }else if (pm->requires_update & UPDATE_PULSE_MODE){ 138 int op, arg; 139 /* the powermate takes an operation and an argument for its pulse algorithm. 140 the operation can be: 141 0: divide the speed 142 1: pulse at normal speed 143 2: multiply the speed 144 the argument only has an effect for operations 0 and 2, and ranges between 145 1 (least effect) to 255 (maximum effect). 146 147 thus, several states are equivalent and are coalesced into one state. 148 149 we map this onto a range from 0 to 510, with: 150 0 -- 254 -- use divide (0 = slowest) 151 255 -- use normal speed 152 256 -- 510 -- use multiple (510 = fastest). 153 154 Only values of 'arg' quite close to 255 are particularly useful/spectacular. 155 */ 156 if (pm->pulse_speed < 255) { 157 op = 0; // divide 158 arg = 255 - pm->pulse_speed; 159 } else if (pm->pulse_speed > 255) { 160 op = 2; // multiply 161 arg = pm->pulse_speed - 255; 162 } else { 163 op = 1; // normal speed 164 arg = 0; // can be any value 165 } 166 pm->configcr->wValue = cpu_to_le16( (pm->pulse_table << 8) | SET_PULSE_MODE ); 167 pm->configcr->wIndex = cpu_to_le16( (arg << 8) | op ); 168 pm->requires_update &= ~UPDATE_PULSE_MODE; 169 } else if (pm->requires_update & UPDATE_STATIC_BRIGHTNESS) { 170 pm->configcr->wValue = cpu_to_le16( SET_STATIC_BRIGHTNESS ); 171 pm->configcr->wIndex = cpu_to_le16( pm->static_brightness ); 172 pm->requires_update &= ~UPDATE_STATIC_BRIGHTNESS; 173 } else { 174 printk(KERN_ERR "powermate: unknown update required"); 175 pm->requires_update = 0; /* fudge the bug */ 176 return; 177 } 178 179 /* printk("powermate: %04x %04x\n", pm->configcr->wValue, pm->configcr->wIndex); */ 180 181 pm->configcr->bRequestType = 0x41; /* vendor request */ 182 pm->configcr->bRequest = 0x01; 183 pm->configcr->wLength = 0; 184 185 usb_fill_control_urb(pm->config, pm->udev, usb_sndctrlpipe(pm->udev, 0), 186 (void *) pm->configcr, NULL, 0, 187 powermate_config_complete, pm); 188 189 if (usb_submit_urb(pm->config, GFP_ATOMIC)) 190 printk(KERN_ERR "powermate: usb_submit_urb(config) failed"); 191 } 192 193 /* Called when our asynchronous control message completes. We may need to issue another immediately */ 194 static void powermate_config_complete(struct urb *urb) 195 { 196 struct powermate_device *pm = urb->context; 197 unsigned long flags; 198 199 if (urb->status) 200 printk(KERN_ERR "powermate: config urb returned %d\n", urb->status); 201 202 spin_lock_irqsave(&pm->lock, flags); 203 powermate_sync_state(pm); 204 spin_unlock_irqrestore(&pm->lock, flags); 205 } 206 207 /* Set the LED up as described and begin the sync with the hardware if required */ 208 static void powermate_pulse_led(struct powermate_device *pm, int static_brightness, int pulse_speed, 209 int pulse_table, int pulse_asleep, int pulse_awake) 210 { 211 unsigned long flags; 212 213 if (pulse_speed < 0) 214 pulse_speed = 0; 215 if (pulse_table < 0) 216 pulse_table = 0; 217 if (pulse_speed > 510) 218 pulse_speed = 510; 219 if (pulse_table > 2) 220 pulse_table = 2; 221 222 pulse_asleep = !!pulse_asleep; 223 pulse_awake = !!pulse_awake; 224 225 226 spin_lock_irqsave(&pm->lock, flags); 227 228 /* mark state updates which are required */ 229 if (static_brightness != pm->static_brightness) { 230 pm->static_brightness = static_brightness; 231 pm->requires_update |= UPDATE_STATIC_BRIGHTNESS; 232 } 233 if (pulse_asleep != pm->pulse_asleep) { 234 pm->pulse_asleep = pulse_asleep; 235 pm->requires_update |= (UPDATE_PULSE_ASLEEP | UPDATE_STATIC_BRIGHTNESS); 236 } 237 if (pulse_awake != pm->pulse_awake) { 238 pm->pulse_awake = pulse_awake; 239 pm->requires_update |= (UPDATE_PULSE_AWAKE | UPDATE_STATIC_BRIGHTNESS); 240 } 241 if (pulse_speed != pm->pulse_speed || pulse_table != pm->pulse_table) { 242 pm->pulse_speed = pulse_speed; 243 pm->pulse_table = pulse_table; 244 pm->requires_update |= UPDATE_PULSE_MODE; 245 } 246 247 powermate_sync_state(pm); 248 249 spin_unlock_irqrestore(&pm->lock, flags); 250 } 251 252 /* Callback from the Input layer when an event arrives from userspace to configure the LED */ 253 static int powermate_input_event(struct input_dev *dev, unsigned int type, unsigned int code, int _value) 254 { 255 unsigned int command = (unsigned int)_value; 256 struct powermate_device *pm = input_get_drvdata(dev); 257 258 if (type == EV_MSC && code == MSC_PULSELED){ 259 /* 260 bits 0- 7: 8 bits: LED brightness 261 bits 8-16: 9 bits: pulsing speed modifier (0 ... 510); 0-254 = slower, 255 = standard, 256-510 = faster. 262 bits 17-18: 2 bits: pulse table (0, 1, 2 valid) 263 bit 19: 1 bit : pulse whilst asleep? 264 bit 20: 1 bit : pulse constantly? 265 */ 266 int static_brightness = command & 0xFF; // bits 0-7 267 int pulse_speed = (command >> 8) & 0x1FF; // bits 8-16 268 int pulse_table = (command >> 17) & 0x3; // bits 17-18 269 int pulse_asleep = (command >> 19) & 0x1; // bit 19 270 int pulse_awake = (command >> 20) & 0x1; // bit 20 271 272 powermate_pulse_led(pm, static_brightness, pulse_speed, pulse_table, pulse_asleep, pulse_awake); 273 } 274 275 return 0; 276 } 277 278 static int powermate_alloc_buffers(struct usb_device *udev, struct powermate_device *pm) 279 { 280 pm->data = usb_alloc_coherent(udev, POWERMATE_PAYLOAD_SIZE_MAX, 281 GFP_KERNEL, &pm->data_dma); 282 if (!pm->data) 283 return -1; 284 285 pm->configcr = kmalloc(sizeof(*(pm->configcr)), GFP_KERNEL); 286 if (!pm->configcr) 287 return -ENOMEM; 288 289 return 0; 290 } 291 292 static void powermate_free_buffers(struct usb_device *udev, struct powermate_device *pm) 293 { 294 usb_free_coherent(udev, POWERMATE_PAYLOAD_SIZE_MAX, 295 pm->data, pm->data_dma); 296 kfree(pm->configcr); 297 } 298 299 /* Called whenever a USB device matching one in our supported devices table is connected */ 300 static int powermate_probe(struct usb_interface *intf, const struct usb_device_id *id) 301 { 302 struct usb_device *udev = interface_to_usbdev (intf); 303 struct usb_host_interface *interface; 304 struct usb_endpoint_descriptor *endpoint; 305 struct powermate_device *pm; 306 struct input_dev *input_dev; 307 int pipe, maxp; 308 int error = -ENOMEM; 309 310 interface = intf->cur_altsetting; 311 if (interface->desc.bNumEndpoints < 1) 312 return -EINVAL; 313 314 endpoint = &interface->endpoint[0].desc; 315 if (!usb_endpoint_is_int_in(endpoint)) 316 return -EIO; 317 318 usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 319 0x0a, USB_TYPE_CLASS | USB_RECIP_INTERFACE, 320 0, interface->desc.bInterfaceNumber, NULL, 0, 321 USB_CTRL_SET_TIMEOUT); 322 323 pm = kzalloc(sizeof(struct powermate_device), GFP_KERNEL); 324 input_dev = input_allocate_device(); 325 if (!pm || !input_dev) 326 goto fail1; 327 328 if (powermate_alloc_buffers(udev, pm)) 329 goto fail2; 330 331 pm->irq = usb_alloc_urb(0, GFP_KERNEL); 332 if (!pm->irq) 333 goto fail2; 334 335 pm->config = usb_alloc_urb(0, GFP_KERNEL); 336 if (!pm->config) 337 goto fail3; 338 339 pm->udev = udev; 340 pm->intf = intf; 341 pm->input = input_dev; 342 343 usb_make_path(udev, pm->phys, sizeof(pm->phys)); 344 strlcat(pm->phys, "/input0", sizeof(pm->phys)); 345 346 spin_lock_init(&pm->lock); 347 348 switch (le16_to_cpu(udev->descriptor.idProduct)) { 349 case POWERMATE_PRODUCT_NEW: 350 input_dev->name = pm_name_powermate; 351 break; 352 case POWERMATE_PRODUCT_OLD: 353 input_dev->name = pm_name_soundknob; 354 break; 355 default: 356 input_dev->name = pm_name_soundknob; 357 printk(KERN_WARNING "powermate: unknown product id %04x\n", 358 le16_to_cpu(udev->descriptor.idProduct)); 359 } 360 361 input_dev->phys = pm->phys; 362 usb_to_input_id(udev, &input_dev->id); 363 input_dev->dev.parent = &intf->dev; 364 365 input_set_drvdata(input_dev, pm); 366 367 input_dev->event = powermate_input_event; 368 369 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) | 370 BIT_MASK(EV_MSC); 371 input_dev->keybit[BIT_WORD(BTN_0)] = BIT_MASK(BTN_0); 372 input_dev->relbit[BIT_WORD(REL_DIAL)] = BIT_MASK(REL_DIAL); 373 input_dev->mscbit[BIT_WORD(MSC_PULSELED)] = BIT_MASK(MSC_PULSELED); 374 375 /* get a handle to the interrupt data pipe */ 376 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress); 377 maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe)); 378 379 if (maxp < POWERMATE_PAYLOAD_SIZE_MIN || maxp > POWERMATE_PAYLOAD_SIZE_MAX) { 380 printk(KERN_WARNING "powermate: Expected payload of %d--%d bytes, found %d bytes!\n", 381 POWERMATE_PAYLOAD_SIZE_MIN, POWERMATE_PAYLOAD_SIZE_MAX, maxp); 382 maxp = POWERMATE_PAYLOAD_SIZE_MAX; 383 } 384 385 usb_fill_int_urb(pm->irq, udev, pipe, pm->data, 386 maxp, powermate_irq, 387 pm, endpoint->bInterval); 388 pm->irq->transfer_dma = pm->data_dma; 389 pm->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 390 391 /* register our interrupt URB with the USB system */ 392 if (usb_submit_urb(pm->irq, GFP_KERNEL)) { 393 error = -EIO; 394 goto fail4; 395 } 396 397 error = input_register_device(pm->input); 398 if (error) 399 goto fail5; 400 401 402 /* force an update of everything */ 403 pm->requires_update = UPDATE_PULSE_ASLEEP | UPDATE_PULSE_AWAKE | UPDATE_PULSE_MODE | UPDATE_STATIC_BRIGHTNESS; 404 powermate_pulse_led(pm, 0x80, 255, 0, 1, 0); // set default pulse parameters 405 406 usb_set_intfdata(intf, pm); 407 return 0; 408 409 fail5: usb_kill_urb(pm->irq); 410 fail4: usb_free_urb(pm->config); 411 fail3: usb_free_urb(pm->irq); 412 fail2: powermate_free_buffers(udev, pm); 413 fail1: input_free_device(input_dev); 414 kfree(pm); 415 return error; 416 } 417 418 /* Called when a USB device we've accepted ownership of is removed */ 419 static void powermate_disconnect(struct usb_interface *intf) 420 { 421 struct powermate_device *pm = usb_get_intfdata (intf); 422 423 usb_set_intfdata(intf, NULL); 424 if (pm) { 425 pm->requires_update = 0; 426 usb_kill_urb(pm->irq); 427 input_unregister_device(pm->input); 428 usb_free_urb(pm->irq); 429 usb_free_urb(pm->config); 430 powermate_free_buffers(interface_to_usbdev(intf), pm); 431 432 kfree(pm); 433 } 434 } 435 436 static const struct usb_device_id powermate_devices[] = { 437 { USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_NEW) }, 438 { USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_OLD) }, 439 { USB_DEVICE(CONTOUR_VENDOR, CONTOUR_JOG) }, 440 { } /* Terminating entry */ 441 }; 442 443 MODULE_DEVICE_TABLE (usb, powermate_devices); 444 445 static struct usb_driver powermate_driver = { 446 .name = "powermate", 447 .probe = powermate_probe, 448 .disconnect = powermate_disconnect, 449 .id_table = powermate_devices, 450 }; 451 452 module_usb_driver(powermate_driver); 453 454 MODULE_AUTHOR( "William R Sowerbutts" ); 455 MODULE_DESCRIPTION( "Griffin Technology, Inc PowerMate driver" ); 456 MODULE_LICENSE("GPL"); 457