LXR linux/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
  62struct 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
  80static char pm_name_powermate[] = "Griffin PowerMate";
  81static char pm_name_soundknob[] = "Griffin SoundKnob";
  82
  83static void powermate_config_complete(struct urb *urb);
  84
  85/* Callback for data arriving from the PowerMate over the USB interrupt pipe */
  86static 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
 114exit:
 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 */
 122static 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 */
 194static 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 */
 208static 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 */
 253static 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
 278static 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
 292static 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 */
 300static 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);
 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 */
 419static 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
 436static 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
 443MODULE_DEVICE_TABLE (usb, powermate_devices);
 444
 445static struct usb_driver powermate_driver = {
 446        .name =         "powermate",
 447        .probe =        powermate_probe,
 448        .disconnect =   powermate_disconnect,
 449        .id_table =     powermate_devices,
 450};
 451
 452module_usb_driver(powermate_driver);
 453
 454MODULE_AUTHOR( "William R Sowerbutts" );
 455MODULE_DESCRIPTION( "Griffin Technology, Inc PowerMate driver" );
 456MODULE_LICENSE("GPL");
 457