2 * A driver for the Griffin Technology, Inc. "PowerMate" USB controller dial.
4 * v1.1, (c)2002 William R Sowerbutts <will@sowerbutts.com>
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.
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.
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.
25 * Griffin were very happy to provide documentation and free hardware for development.
27 * Some userspace tools are available on the web: http://sowerbutts.com/powermate/
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>
38 #define POWERMATE_VENDOR 0x077d /* Griffin Technology, Inc. */
39 #define POWERMATE_PRODUCT_NEW 0x0410 /* Griffin PowerMate */
40 #define POWERMATE_PRODUCT_OLD 0x04AA /* Griffin soundKnob */
42 #define CONTOUR_VENDOR 0x05f3 /* Contour Design, Inc. */
43 #define CONTOUR_JOG 0x0240 /* Jog and Shuttle */
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
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)
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 {
65 struct urb *irq, *config;
66 struct usb_ctrlrequest *configcr;
67 dma_addr_t configcr_dma;
68 struct usb_device *udev;
69 struct input_dev *input;
71 int static_brightness;
76 int requires_update; // physical settings which are out of sync
80 static char pm_name_powermate[] = "Griffin PowerMate";
81 static char pm_name_soundknob[] = "Griffin SoundKnob";
83 static void powermate_config_complete(struct urb *urb);
85 /* Callback for data arriving from the PowerMate over the USB interrupt pipe */
86 static void powermate_irq(struct urb *urb)
88 struct powermate_device *pm = urb->context;
91 switch (urb->status) {
98 /* this urb is terminated, clean up */
99 dbg("%s - urb shutting down with status: %d", __func__, urb->status);
102 dbg("%s - nonzero urb status received: %d", __func__, urb->status);
106 /* handle updates to device state */
107 input_report_key(pm->input, BTN_0, pm->data[0] & 0x01);
108 input_report_rel(pm->input, REL_DIAL, pm->data[1]);
109 input_sync(pm->input);
112 retval = usb_submit_urb (urb, GFP_ATOMIC);
114 err ("%s - usb_submit_urb failed with result %d",
118 /* Decide if we need to issue a control message and do so. Must be called with pm->lock taken */
119 static void powermate_sync_state(struct powermate_device *pm)
121 if (pm->requires_update == 0)
122 return; /* no updates are required */
123 if (pm->config->status == -EINPROGRESS)
124 return; /* an update is already in progress; it'll issue this update when it completes */
126 if (pm->requires_update & UPDATE_PULSE_ASLEEP){
127 pm->configcr->wValue = cpu_to_le16( SET_PULSE_ASLEEP );
128 pm->configcr->wIndex = cpu_to_le16( pm->pulse_asleep ? 1 : 0 );
129 pm->requires_update &= ~UPDATE_PULSE_ASLEEP;
130 }else if (pm->requires_update & UPDATE_PULSE_AWAKE){
131 pm->configcr->wValue = cpu_to_le16( SET_PULSE_AWAKE );
132 pm->configcr->wIndex = cpu_to_le16( pm->pulse_awake ? 1 : 0 );
133 pm->requires_update &= ~UPDATE_PULSE_AWAKE;
134 }else if (pm->requires_update & UPDATE_PULSE_MODE){
136 /* the powermate takes an operation and an argument for its pulse algorithm.
137 the operation can be:
139 1: pulse at normal speed
140 2: multiply the speed
141 the argument only has an effect for operations 0 and 2, and ranges between
142 1 (least effect) to 255 (maximum effect).
144 thus, several states are equivalent and are coalesced into one state.
146 we map this onto a range from 0 to 510, with:
147 0 -- 254 -- use divide (0 = slowest)
148 255 -- use normal speed
149 256 -- 510 -- use multiple (510 = fastest).
151 Only values of 'arg' quite close to 255 are particularly useful/spectacular.
153 if (pm->pulse_speed < 255) {
155 arg = 255 - pm->pulse_speed;
156 } else if (pm->pulse_speed > 255) {
158 arg = pm->pulse_speed - 255;
160 op = 1; // normal speed
161 arg = 0; // can be any value
163 pm->configcr->wValue = cpu_to_le16( (pm->pulse_table << 8) | SET_PULSE_MODE );
164 pm->configcr->wIndex = cpu_to_le16( (arg << 8) | op );
165 pm->requires_update &= ~UPDATE_PULSE_MODE;
166 } else if (pm->requires_update & UPDATE_STATIC_BRIGHTNESS) {
167 pm->configcr->wValue = cpu_to_le16( SET_STATIC_BRIGHTNESS );
168 pm->configcr->wIndex = cpu_to_le16( pm->static_brightness );
169 pm->requires_update &= ~UPDATE_STATIC_BRIGHTNESS;
171 printk(KERN_ERR "powermate: unknown update required");
172 pm->requires_update = 0; /* fudge the bug */
176 /* printk("powermate: %04x %04x\n", pm->configcr->wValue, pm->configcr->wIndex); */
178 pm->configcr->bRequestType = 0x41; /* vendor request */
179 pm->configcr->bRequest = 0x01;
180 pm->configcr->wLength = 0;
182 usb_fill_control_urb(pm->config, pm->udev, usb_sndctrlpipe(pm->udev, 0),
183 (void *) pm->configcr, NULL, 0,
184 powermate_config_complete, pm);
185 pm->config->setup_dma = pm->configcr_dma;
186 pm->config->transfer_flags |= URB_NO_SETUP_DMA_MAP;
188 if (usb_submit_urb(pm->config, GFP_ATOMIC))
189 printk(KERN_ERR "powermate: usb_submit_urb(config) failed");
192 /* Called when our asynchronous control message completes. We may need to issue another immediately */
193 static void powermate_config_complete(struct urb *urb)
195 struct powermate_device *pm = urb->context;
199 printk(KERN_ERR "powermate: config urb returned %d\n", urb->status);
201 spin_lock_irqsave(&pm->lock, flags);
202 powermate_sync_state(pm);
203 spin_unlock_irqrestore(&pm->lock, flags);
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)
216 if (pulse_speed > 510)
221 pulse_asleep = !!pulse_asleep;
222 pulse_awake = !!pulse_awake;
225 spin_lock_irqsave(&pm->lock, flags);
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;
232 if (pulse_asleep != pm->pulse_asleep) {
233 pm->pulse_asleep = pulse_asleep;
234 pm->requires_update |= (UPDATE_PULSE_ASLEEP | UPDATE_STATIC_BRIGHTNESS);
236 if (pulse_awake != pm->pulse_awake) {
237 pm->pulse_awake = pulse_awake;
238 pm->requires_update |= (UPDATE_PULSE_AWAKE | UPDATE_STATIC_BRIGHTNESS);
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;
246 powermate_sync_state(pm);
248 spin_unlock_irqrestore(&pm->lock, flags);
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)
254 unsigned int command = (unsigned int)_value;
255 struct powermate_device *pm = input_get_drvdata(dev);
257 if (type == EV_MSC && code == MSC_PULSELED){
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?
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
271 powermate_pulse_led(pm, static_brightness, pulse_speed, pulse_table, pulse_asleep, pulse_awake);
277 static int powermate_alloc_buffers(struct usb_device *udev, struct powermate_device *pm)
279 pm->data = usb_buffer_alloc(udev, POWERMATE_PAYLOAD_SIZE_MAX,
280 GFP_ATOMIC, &pm->data_dma);
284 pm->configcr = usb_buffer_alloc(udev, sizeof(*(pm->configcr)),
285 GFP_ATOMIC, &pm->configcr_dma);
292 static void powermate_free_buffers(struct usb_device *udev, struct powermate_device *pm)
294 usb_buffer_free(udev, POWERMATE_PAYLOAD_SIZE_MAX,
295 pm->data, pm->data_dma);
296 usb_buffer_free(udev, sizeof(*(pm->configcr)),
297 pm->configcr, pm->configcr_dma);
300 /* Called whenever a USB device matching one in our supported devices table is connected */
301 static int powermate_probe(struct usb_interface *intf, const struct usb_device_id *id)
303 struct usb_device *udev = interface_to_usbdev (intf);
304 struct usb_host_interface *interface;
305 struct usb_endpoint_descriptor *endpoint;
306 struct powermate_device *pm;
307 struct input_dev *input_dev;
311 interface = intf->cur_altsetting;
312 endpoint = &interface->endpoint[0].desc;
313 if (!usb_endpoint_is_int_in(endpoint))
316 usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
317 0x0a, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
318 0, interface->desc.bInterfaceNumber, NULL, 0,
319 USB_CTRL_SET_TIMEOUT);
321 pm = kzalloc(sizeof(struct powermate_device), GFP_KERNEL);
322 input_dev = input_allocate_device();
323 if (!pm || !input_dev)
326 if (powermate_alloc_buffers(udev, pm))
329 pm->irq = usb_alloc_urb(0, GFP_KERNEL);
333 pm->config = usb_alloc_urb(0, GFP_KERNEL);
338 pm->input = input_dev;
340 usb_make_path(udev, pm->phys, sizeof(pm->phys));
341 strlcpy(pm->phys, "/input0", sizeof(pm->phys));
343 spin_lock_init(&pm->lock);
345 switch (le16_to_cpu(udev->descriptor.idProduct)) {
346 case POWERMATE_PRODUCT_NEW:
347 input_dev->name = pm_name_powermate;
349 case POWERMATE_PRODUCT_OLD:
350 input_dev->name = pm_name_soundknob;
353 input_dev->name = pm_name_soundknob;
354 printk(KERN_WARNING "powermate: unknown product id %04x\n",
355 le16_to_cpu(udev->descriptor.idProduct));
358 input_dev->phys = pm->phys;
359 usb_to_input_id(udev, &input_dev->id);
360 input_dev->dev.parent = &intf->dev;
362 input_set_drvdata(input_dev, pm);
364 input_dev->event = powermate_input_event;
366 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) |
368 input_dev->keybit[BIT_WORD(BTN_0)] = BIT_MASK(BTN_0);
369 input_dev->relbit[BIT_WORD(REL_DIAL)] = BIT_MASK(REL_DIAL);
370 input_dev->mscbit[BIT_WORD(MSC_PULSELED)] = BIT_MASK(MSC_PULSELED);
372 /* get a handle to the interrupt data pipe */
373 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
374 maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
376 if (maxp < POWERMATE_PAYLOAD_SIZE_MIN || maxp > POWERMATE_PAYLOAD_SIZE_MAX) {
377 printk(KERN_WARNING "powermate: Expected payload of %d--%d bytes, found %d bytes!\n",
378 POWERMATE_PAYLOAD_SIZE_MIN, POWERMATE_PAYLOAD_SIZE_MAX, maxp);
379 maxp = POWERMATE_PAYLOAD_SIZE_MAX;
382 usb_fill_int_urb(pm->irq, udev, pipe, pm->data,
384 pm, endpoint->bInterval);
385 pm->irq->transfer_dma = pm->data_dma;
386 pm->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
388 /* register our interrupt URB with the USB system */
389 if (usb_submit_urb(pm->irq, GFP_KERNEL)) {
394 error = input_register_device(pm->input);
399 /* force an update of everything */
400 pm->requires_update = UPDATE_PULSE_ASLEEP | UPDATE_PULSE_AWAKE | UPDATE_PULSE_MODE | UPDATE_STATIC_BRIGHTNESS;
401 powermate_pulse_led(pm, 0x80, 255, 0, 1, 0); // set default pulse parameters
403 usb_set_intfdata(intf, pm);
406 fail5: usb_kill_urb(pm->irq);
407 fail4: usb_free_urb(pm->config);
408 fail3: usb_free_urb(pm->irq);
409 fail2: powermate_free_buffers(udev, pm);
410 fail1: input_free_device(input_dev);
415 /* Called when a USB device we've accepted ownership of is removed */
416 static void powermate_disconnect(struct usb_interface *intf)
418 struct powermate_device *pm = usb_get_intfdata (intf);
420 usb_set_intfdata(intf, NULL);
422 pm->requires_update = 0;
423 usb_kill_urb(pm->irq);
424 input_unregister_device(pm->input);
425 usb_free_urb(pm->irq);
426 usb_free_urb(pm->config);
427 powermate_free_buffers(interface_to_usbdev(intf), pm);
433 static struct usb_device_id powermate_devices [] = {
434 { USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_NEW) },
435 { USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_OLD) },
436 { USB_DEVICE(CONTOUR_VENDOR, CONTOUR_JOG) },
437 { } /* Terminating entry */
440 MODULE_DEVICE_TABLE (usb, powermate_devices);
442 static struct usb_driver powermate_driver = {
444 .probe = powermate_probe,
445 .disconnect = powermate_disconnect,
446 .id_table = powermate_devices,
449 static int __init powermate_init(void)
451 return usb_register(&powermate_driver);
454 static void __exit powermate_cleanup(void)
456 usb_deregister(&powermate_driver);
459 module_init(powermate_init);
460 module_exit(powermate_cleanup);
462 MODULE_AUTHOR( "William R Sowerbutts" );
463 MODULE_DESCRIPTION( "Griffin Technology, Inc PowerMate driver" );
464 MODULE_LICENSE("GPL");