drivers/input/misc/powermate.c

   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
 198         if (urb->status)
 199                 printk(KERN_ERR "powermate: config urb returned %d\n", urb->status);
 200
 201         guard(spinlock_irqsave)(&pm->lock);
 202         powermate_sync_state(pm);
 203 }
 204
 205 /* Set the LED up as described and begin the sync with the hardware if required */
 206 static void powermate_pulse_led(struct powermate_device *pm, int static_brightness, int pulse_speed,
 207                                 int pulse_table, int pulse_asleep, int pulse_awake)
 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         guard(spinlock_irqsave)(&pm->lock);
 222
 223         /* mark state updates which are required */
 224         if (static_brightness != pm->static_brightness) {
 225                 pm->static_brightness = static_brightness;
 226                 pm->requires_update |= UPDATE_STATIC_BRIGHTNESS;
 227         }
 228         if (pulse_asleep != pm->pulse_asleep) {
 229                 pm->pulse_asleep = pulse_asleep;
 230                 pm->requires_update |= (UPDATE_PULSE_ASLEEP | UPDATE_STATIC_BRIGHTNESS);
 231         }
 232         if (pulse_awake != pm->pulse_awake) {
 233                 pm->pulse_awake = pulse_awake;
 234                 pm->requires_update |= (UPDATE_PULSE_AWAKE | UPDATE_STATIC_BRIGHTNESS);
 235         }
 236         if (pulse_speed != pm->pulse_speed || pulse_table != pm->pulse_table) {
 237                 pm->pulse_speed = pulse_speed;
 238                 pm->pulse_table = pulse_table;
 239                 pm->requires_update |= UPDATE_PULSE_MODE;
 240         }
 241
 242         powermate_sync_state(pm);
 243 }
 244
 245 /* Callback from the Input layer when an event arrives from userspace to configure the LED */
 246 static int powermate_input_event(struct input_dev *dev, unsigned int type, unsigned int code, int _value)
 247 {
 248         unsigned int command = (unsigned int)_value;
 249         struct powermate_device *pm = input_get_drvdata(dev);
 250
 251         if (type == EV_MSC && code == MSC_PULSELED){
 252                 /*
 253                     bits  0- 7: 8 bits: LED brightness
 254                     bits  8-16: 9 bits: pulsing speed modifier (0 ... 510); 0-254 = slower, 255 = standard, 256-510 = faster.
 255                     bits 17-18: 2 bits: pulse table (0, 1, 2 valid)
 256                     bit     19: 1 bit : pulse whilst asleep?
 257                     bit     20: 1 bit : pulse constantly?
 258                 */
 259                 int static_brightness = command & 0xFF;   // bits 0-7
 260                 int pulse_speed = (command >> 8) & 0x1FF; // bits 8-16
 261                 int pulse_table = (command >> 17) & 0x3;  // bits 17-18
 262                 int pulse_asleep = (command >> 19) & 0x1; // bit 19
 263                 int pulse_awake  = (command >> 20) & 0x1; // bit 20
 264
 265                 powermate_pulse_led(pm, static_brightness, pulse_speed, pulse_table, pulse_asleep, pulse_awake);
 266         }
 267
 268         return 0;
 269 }
 270
 271 static int powermate_alloc_buffers(struct usb_device *udev, struct powermate_device *pm)
 272 {
 273         pm->data = usb_alloc_coherent(udev, POWERMATE_PAYLOAD_SIZE_MAX,
 274                                       GFP_KERNEL, &pm->data_dma);
 275         if (!pm->data)
 276                 return -1;
 277
 278         pm->configcr = kmalloc(sizeof(*(pm->configcr)), GFP_KERNEL);
 279         if (!pm->configcr)
 280                 return -ENOMEM;
 281
 282         return 0;
 283 }
 284
 285 static void powermate_free_buffers(struct usb_device *udev, struct powermate_device *pm)
 286 {
 287         usb_free_coherent(udev, POWERMATE_PAYLOAD_SIZE_MAX,
 288                           pm->data, pm->data_dma);
 289         kfree(pm->configcr);
 290 }
 291
 292 /* Called whenever a USB device matching one in our supported devices table is connected */
 293 static int powermate_probe(struct usb_interface *intf, const struct usb_device_id *id)
 294 {
 295         struct usb_device *udev = interface_to_usbdev (intf);
 296         struct usb_host_interface *interface;
 297         struct usb_endpoint_descriptor *endpoint;
 298         struct powermate_device *pm;
 299         struct input_dev *input_dev;
 300         int pipe, maxp;
 301         int error = -ENOMEM;
 302
 303         interface = intf->cur_altsetting;
 304         if (interface->desc.bNumEndpoints < 1)
 305                 return -EINVAL;
 306
 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(*pm), 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->intf = intf;
 334         pm->input = input_dev;
 335
 336         usb_make_path(udev, pm->phys, sizeof(pm->phys));
 337         strlcat(pm->phys, "/input0", sizeof(pm->phys));
 338
 339         spin_lock_init(&pm->lock);
 340
 341         switch (le16_to_cpu(udev->descriptor.idProduct)) {
 342         case POWERMATE_PRODUCT_NEW:
 343                 input_dev->name = pm_name_powermate;
 344                 break;
 345         case POWERMATE_PRODUCT_OLD:
 346                 input_dev->name = pm_name_soundknob;
 347                 break;
 348         default:
 349                 input_dev->name = pm_name_soundknob;
 350                 printk(KERN_WARNING "powermate: unknown product id %04x\n",
 351                        le16_to_cpu(udev->descriptor.idProduct));
 352         }
 353
 354         input_dev->phys = pm->phys;
 355         usb_to_input_id(udev, &input_dev->id);
 356         input_dev->dev.parent = &intf->dev;
 357
 358         input_set_drvdata(input_dev, pm);
 359
 360         input_dev->event = powermate_input_event;
 361
 362         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) |
 363                 BIT_MASK(EV_MSC);
 364         input_dev->keybit[BIT_WORD(BTN_0)] = BIT_MASK(BTN_0);
 365         input_dev->relbit[BIT_WORD(REL_DIAL)] = BIT_MASK(REL_DIAL);
 366         input_dev->mscbit[BIT_WORD(MSC_PULSELED)] = BIT_MASK(MSC_PULSELED);
 367
 368         /* get a handle to the interrupt data pipe */
 369         pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
 370         maxp = usb_maxpacket(udev, pipe);
 371
 372         if (maxp < POWERMATE_PAYLOAD_SIZE_MIN || maxp > POWERMATE_PAYLOAD_SIZE_MAX) {
 373                 printk(KERN_WARNING "powermate: Expected payload of %d--%d bytes, found %d bytes!\n",
 374                         POWERMATE_PAYLOAD_SIZE_MIN, POWERMATE_PAYLOAD_SIZE_MAX, maxp);
 375                 maxp = POWERMATE_PAYLOAD_SIZE_MAX;
 376         }
 377
 378         usb_fill_int_urb(pm->irq, udev, pipe, pm->data,
 379                          maxp, powermate_irq,
 380                          pm, endpoint->bInterval);
 381         pm->irq->transfer_dma = pm->data_dma;
 382         pm->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 383
 384         /* register our interrupt URB with the USB system */
 385         if (usb_submit_urb(pm->irq, GFP_KERNEL)) {
 386                 error = -EIO;
 387                 goto fail4;
 388         }
 389
 390         error = input_register_device(pm->input);
 391         if (error)
 392                 goto fail5;
 393
 394
 395         /* force an update of everything */
 396         pm->requires_update = UPDATE_PULSE_ASLEEP | UPDATE_PULSE_AWAKE | UPDATE_PULSE_MODE | UPDATE_STATIC_BRIGHTNESS;
 397         powermate_pulse_led(pm, 0x80, 255, 0, 1, 0); // set default pulse parameters
 398
 399         usb_set_intfdata(intf, pm);
 400         return 0;
 401
 402  fail5: usb_kill_urb(pm->irq);
 403  fail4: usb_free_urb(pm->config);
 404  fail3: usb_free_urb(pm->irq);
 405  fail2: powermate_free_buffers(udev, pm);
 406  fail1: input_free_device(input_dev);
 407         kfree(pm);
 408         return error;
 409 }
 410
 411 /* Called when a USB device we've accepted ownership of is removed */
 412 static void powermate_disconnect(struct usb_interface *intf)
 413 {
 414         struct powermate_device *pm = usb_get_intfdata (intf);
 415
 416         usb_set_intfdata(intf, NULL);
 417         if (pm) {
 418                 pm->requires_update = 0;
 419                 usb_kill_urb(pm->irq);
 420                 input_unregister_device(pm->input);
 421                 usb_kill_urb(pm->config);
 422                 usb_free_urb(pm->irq);
 423                 usb_free_urb(pm->config);
 424                 powermate_free_buffers(interface_to_usbdev(intf), pm);
 425
 426                 kfree(pm);
 427         }
 428 }
 429
 430 static const struct usb_device_id powermate_devices[] = {
 431         { USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_NEW) },
 432         { USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_OLD) },
 433         { USB_DEVICE(CONTOUR_VENDOR, CONTOUR_JOG) },
 434         { } /* Terminating entry */
 435 };
 436
 437 MODULE_DEVICE_TABLE (usb, powermate_devices);
 438
 439 static struct usb_driver powermate_driver = {
 440         .name =         "powermate",
 441         .probe =        powermate_probe,
 442         .disconnect =   powermate_disconnect,
 443         .id_table =     powermate_devices,
 444 };
 445
 446 module_usb_driver(powermate_driver);
 447
 448 MODULE_AUTHOR( "William R Sowerbutts" );
 449 MODULE_DESCRIPTION( "Griffin Technology, Inc PowerMate driver" );
 450 MODULE_LICENSE("GPL");