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, struct pt_regs *regs);
85 /* Callback for data arriving from the PowerMate over the USB interrupt pipe */
86 static void powermate_irq(struct urb *urb, struct pt_regs *regs)
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", __FUNCTION__, urb->status);
102 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
106 /* handle updates to device state */
107 input_regs(pm->input, regs);
108 input_report_key(pm->input, BTN_0, pm->data[0] & 0x01);
109 input_report_rel(pm->input, REL_DIAL, pm->data[1]);
110 input_sync(pm->input);
113 retval = usb_submit_urb (urb, GFP_ATOMIC);
115 err ("%s - usb_submit_urb failed with result %d",
116 __FUNCTION__, retval);
119 /* Decide if we need to issue a control message and do so. Must be called with pm->lock taken */
120 static void powermate_sync_state(struct powermate_device *pm)
122 if (pm->requires_update == 0)
123 return; /* no updates are required */
124 if (pm->config->status == -EINPROGRESS)
125 return; /* an update is already in progress; it'll issue this update when it completes */
127 if (pm->requires_update & UPDATE_PULSE_ASLEEP){
128 pm->configcr->wValue = cpu_to_le16( SET_PULSE_ASLEEP );
129 pm->configcr->wIndex = cpu_to_le16( pm->pulse_asleep ? 1 : 0 );
130 pm->requires_update &= ~UPDATE_PULSE_ASLEEP;
131 }else if (pm->requires_update & UPDATE_PULSE_AWAKE){
132 pm->configcr->wValue = cpu_to_le16( SET_PULSE_AWAKE );
133 pm->configcr->wIndex = cpu_to_le16( pm->pulse_awake ? 1 : 0 );
134 pm->requires_update &= ~UPDATE_PULSE_AWAKE;
135 }else if (pm->requires_update & UPDATE_PULSE_MODE){
137 /* the powermate takes an operation and an argument for its pulse algorithm.
138 the operation can be:
140 1: pulse at normal speed
141 2: multiply the speed
142 the argument only has an effect for operations 0 and 2, and ranges between
143 1 (least effect) to 255 (maximum effect).
145 thus, several states are equivalent and are coalesced into one state.
147 we map this onto a range from 0 to 510, with:
148 0 -- 254 -- use divide (0 = slowest)
149 255 -- use normal speed
150 256 -- 510 -- use multiple (510 = fastest).
152 Only values of 'arg' quite close to 255 are particularly useful/spectacular.
154 if (pm->pulse_speed < 255) {
156 arg = 255 - pm->pulse_speed;
157 } else if (pm->pulse_speed > 255) {
159 arg = pm->pulse_speed - 255;
161 op = 1; // normal speed
162 arg = 0; // can be any value
164 pm->configcr->wValue = cpu_to_le16( (pm->pulse_table << 8) | SET_PULSE_MODE );
165 pm->configcr->wIndex = cpu_to_le16( (arg << 8) | op );
166 pm->requires_update &= ~UPDATE_PULSE_MODE;
167 } else if (pm->requires_update & UPDATE_STATIC_BRIGHTNESS) {
168 pm->configcr->wValue = cpu_to_le16( SET_STATIC_BRIGHTNESS );
169 pm->configcr->wIndex = cpu_to_le16( pm->static_brightness );
170 pm->requires_update &= ~UPDATE_STATIC_BRIGHTNESS;
172 printk(KERN_ERR "powermate: unknown update required");
173 pm->requires_update = 0; /* fudge the bug */
177 /* printk("powermate: %04x %04x\n", pm->configcr->wValue, pm->configcr->wIndex); */
179 pm->configcr->bRequestType = 0x41; /* vendor request */
180 pm->configcr->bRequest = 0x01;
181 pm->configcr->wLength = 0;
183 usb_fill_control_urb(pm->config, pm->udev, usb_sndctrlpipe(pm->udev, 0),
184 (void *) pm->configcr, NULL, 0,
185 powermate_config_complete, pm);
186 pm->config->setup_dma = pm->configcr_dma;
187 pm->config->transfer_flags |= URB_NO_SETUP_DMA_MAP;
189 if (usb_submit_urb(pm->config, GFP_ATOMIC))
190 printk(KERN_ERR "powermate: usb_submit_urb(config) failed");
193 /* Called when our asynchronous control message completes. We may need to issue another immediately */
194 static void powermate_config_complete(struct urb *urb, struct pt_regs *regs)
196 struct powermate_device *pm = urb->context;
200 printk(KERN_ERR "powermate: config urb returned %d\n", urb->status);
202 spin_lock_irqsave(&pm->lock, flags);
203 powermate_sync_state(pm);
204 spin_unlock_irqrestore(&pm->lock, flags);
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)
217 if (pulse_speed > 510)
222 pulse_asleep = !!pulse_asleep;
223 pulse_awake = !!pulse_awake;
226 spin_lock_irqsave(&pm->lock, flags);
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;
233 if (pulse_asleep != pm->pulse_asleep) {
234 pm->pulse_asleep = pulse_asleep;
235 pm->requires_update |= (UPDATE_PULSE_ASLEEP | UPDATE_STATIC_BRIGHTNESS);
237 if (pulse_awake != pm->pulse_awake) {
238 pm->pulse_awake = pulse_awake;
239 pm->requires_update |= (UPDATE_PULSE_AWAKE | UPDATE_STATIC_BRIGHTNESS);
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;
247 powermate_sync_state(pm);
249 spin_unlock_irqrestore(&pm->lock, flags);
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)
255 unsigned int command = (unsigned int)_value;
256 struct powermate_device *pm = dev->private;
258 if (type == EV_MSC && code == MSC_PULSELED){
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?
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
272 powermate_pulse_led(pm, static_brightness, pulse_speed, pulse_table, pulse_asleep, pulse_awake);
278 static int powermate_alloc_buffers(struct usb_device *udev, struct powermate_device *pm)
280 pm->data = usb_buffer_alloc(udev, POWERMATE_PAYLOAD_SIZE_MAX,
281 SLAB_ATOMIC, &pm->data_dma);
285 pm->configcr = usb_buffer_alloc(udev, sizeof(*(pm->configcr)),
286 SLAB_ATOMIC, &pm->configcr_dma);
293 static void powermate_free_buffers(struct usb_device *udev, struct powermate_device *pm)
296 usb_buffer_free(udev, POWERMATE_PAYLOAD_SIZE_MAX,
297 pm->data, pm->data_dma);
299 usb_buffer_free(udev, sizeof(*(pm->configcr)),
300 pm->configcr, pm->configcr_dma);
303 /* Called whenever a USB device matching one in our supported devices table is connected */
304 static int powermate_probe(struct usb_interface *intf, const struct usb_device_id *id)
306 struct usb_device *udev = interface_to_usbdev (intf);
307 struct usb_host_interface *interface;
308 struct usb_endpoint_descriptor *endpoint;
309 struct powermate_device *pm;
310 struct input_dev *input_dev;
314 interface = intf->cur_altsetting;
315 endpoint = &interface->endpoint[0].desc;
316 if (!(endpoint->bEndpointAddress & 0x80))
318 if ((endpoint->bmAttributes & 3) != 3)
321 usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
322 0x0a, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
323 0, interface->desc.bInterfaceNumber, NULL, 0,
324 USB_CTRL_SET_TIMEOUT);
326 pm = kzalloc(sizeof(struct powermate_device), GFP_KERNEL);
327 input_dev = input_allocate_device();
328 if (!pm || !input_dev)
331 if (powermate_alloc_buffers(udev, pm))
334 pm->irq = usb_alloc_urb(0, GFP_KERNEL);
338 pm->config = usb_alloc_urb(0, GFP_KERNEL);
343 pm->input = input_dev;
345 usb_make_path(udev, pm->phys, sizeof(pm->phys));
346 strlcpy(pm->phys, "/input0", sizeof(pm->phys));
348 spin_lock_init(&pm->lock);
350 switch (le16_to_cpu(udev->descriptor.idProduct)) {
351 case POWERMATE_PRODUCT_NEW:
352 input_dev->name = pm_name_powermate;
354 case POWERMATE_PRODUCT_OLD:
355 input_dev->name = pm_name_soundknob;
358 input_dev->name = pm_name_soundknob;
359 printk(KERN_WARNING "powermate: unknown product id %04x\n",
360 le16_to_cpu(udev->descriptor.idProduct));
363 input_dev->phys = pm->phys;
364 usb_to_input_id(udev, &input_dev->id);
365 input_dev->cdev.dev = &intf->dev;
366 input_dev->private = pm;
368 input_dev->event = powermate_input_event;
370 input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_REL) | BIT(EV_MSC);
371 input_dev->keybit[LONG(BTN_0)] = BIT(BTN_0);
372 input_dev->relbit[LONG(REL_DIAL)] = BIT(REL_DIAL);
373 input_dev->mscbit[LONG(MSC_PULSELED)] = BIT(MSC_PULSELED);
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));
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;
385 usb_fill_int_urb(pm->irq, udev, pipe, pm->data,
387 pm, endpoint->bInterval);
388 pm->irq->transfer_dma = pm->data_dma;
389 pm->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
391 /* register our interrupt URB with the USB system */
392 if (usb_submit_urb(pm->irq, GFP_KERNEL)) {
397 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 fail4: usb_free_urb(pm->config);
407 fail3: usb_free_urb(pm->irq);
408 fail2: powermate_free_buffers(udev, pm);
409 fail1: input_free_device(input_dev);
414 /* Called when a USB device we've accepted ownership of is removed */
415 static void powermate_disconnect(struct usb_interface *intf)
417 struct powermate_device *pm = usb_get_intfdata (intf);
419 usb_set_intfdata(intf, NULL);
421 pm->requires_update = 0;
422 usb_kill_urb(pm->irq);
423 input_unregister_device(pm->input);
424 usb_free_urb(pm->irq);
425 usb_free_urb(pm->config);
426 powermate_free_buffers(interface_to_usbdev(intf), pm);
432 static struct usb_device_id powermate_devices [] = {
433 { USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_NEW) },
434 { USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_OLD) },
435 { USB_DEVICE(CONTOUR_VENDOR, CONTOUR_JOG) },
436 { } /* Terminating entry */
439 MODULE_DEVICE_TABLE (usb, powermate_devices);
441 static struct usb_driver powermate_driver = {
443 .probe = powermate_probe,
444 .disconnect = powermate_disconnect,
445 .id_table = powermate_devices,
448 static int __init powermate_init(void)
450 return usb_register(&powermate_driver);
453 static void __exit powermate_cleanup(void)
455 usb_deregister(&powermate_driver);
458 module_init(powermate_init);
459 module_exit(powermate_cleanup);
461 MODULE_AUTHOR( "William R Sowerbutts" );
462 MODULE_DESCRIPTION( "Griffin Technology, Inc PowerMate driver" );
463 MODULE_LICENSE("GPL");