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/input.h>
34 #include <linux/module.h>
35 #include <linux/init.h>
36 #include <linux/spinlock.h>
37 #include <linux/usb.h>
38 #include <linux/usb_input.h>
40 #define POWERMATE_VENDOR 0x077d /* Griffin Technology, Inc. */
41 #define POWERMATE_PRODUCT_NEW 0x0410 /* Griffin PowerMate */
42 #define POWERMATE_PRODUCT_OLD 0x04AA /* Griffin soundKnob */
44 #define CONTOUR_VENDOR 0x05f3 /* Contour Design, Inc. */
45 #define CONTOUR_JOG 0x0240 /* Jog and Shuttle */
47 /* these are the command codes we send to the device */
48 #define SET_STATIC_BRIGHTNESS 0x01
49 #define SET_PULSE_ASLEEP 0x02
50 #define SET_PULSE_AWAKE 0x03
51 #define SET_PULSE_MODE 0x04
53 /* these refer to bits in the powermate_device's requires_update field. */
54 #define UPDATE_STATIC_BRIGHTNESS (1<<0)
55 #define UPDATE_PULSE_ASLEEP (1<<1)
56 #define UPDATE_PULSE_AWAKE (1<<2)
57 #define UPDATE_PULSE_MODE (1<<3)
59 /* at least two versions of the hardware exist, with differing payload
60 sizes. the first three bytes always contain the "interesting" data in
61 the relevant format. */
62 #define POWERMATE_PAYLOAD_SIZE_MAX 6
63 #define POWERMATE_PAYLOAD_SIZE_MIN 3
64 struct powermate_device {
67 struct urb *irq, *config;
68 struct usb_ctrlrequest *configcr;
69 dma_addr_t configcr_dma;
70 struct usb_device *udev;
71 struct input_dev input;
73 int static_brightness;
78 int requires_update; // physical settings which are out of sync
82 static char pm_name_powermate[] = "Griffin PowerMate";
83 static char pm_name_soundknob[] = "Griffin SoundKnob";
85 static void powermate_config_complete(struct urb *urb, struct pt_regs *regs);
87 /* Callback for data arriving from the PowerMate over the USB interrupt pipe */
88 static void powermate_irq(struct urb *urb, struct pt_regs *regs)
90 struct powermate_device *pm = urb->context;
93 switch (urb->status) {
100 /* this urb is terminated, clean up */
101 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
104 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
108 /* handle updates to device state */
109 input_regs(&pm->input, regs);
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);
115 retval = usb_submit_urb (urb, GFP_ATOMIC);
117 err ("%s - usb_submit_urb failed with result %d",
118 __FUNCTION__, retval);
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)
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 */
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){
139 /* the powermate takes an operation and an argument for its pulse algorithm.
140 the operation can be:
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).
147 thus, several states are equivalent and are coalesced into one state.
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).
154 Only values of 'arg' quite close to 255 are particularly useful/spectacular.
156 if (pm->pulse_speed < 255){
158 arg = 255 - pm->pulse_speed;
159 } else if (pm->pulse_speed > 255){
161 arg = pm->pulse_speed - 255;
163 op = 1; // normal speed
164 arg = 0; // can be any value
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;
174 printk(KERN_ERR "powermate: unknown update required");
175 pm->requires_update = 0; /* fudge the bug */
179 /* printk("powermate: %04x %04x\n", pm->configcr->wValue, pm->configcr->wIndex); */
181 pm->configcr->bRequestType = 0x41; /* vendor request */
182 pm->configcr->bRequest = 0x01;
183 pm->configcr->wLength = 0;
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 pm->config->setup_dma = pm->configcr_dma;
189 pm->config->transfer_flags |= URB_NO_SETUP_DMA_MAP;
191 if (usb_submit_urb(pm->config, GFP_ATOMIC))
192 printk(KERN_ERR "powermate: usb_submit_urb(config) failed");
195 /* Called when our asynchronous control message completes. We may need to issue another immediately */
196 static void powermate_config_complete(struct urb *urb, struct pt_regs *regs)
198 struct powermate_device *pm = urb->context;
202 printk(KERN_ERR "powermate: config urb returned %d\n", urb->status);
204 spin_lock_irqsave(&pm->lock, flags);
205 powermate_sync_state(pm);
206 spin_unlock_irqrestore(&pm->lock, flags);
209 /* Set the LED up as described and begin the sync with the hardware if required */
210 static void powermate_pulse_led(struct powermate_device *pm, int static_brightness, int pulse_speed,
211 int pulse_table, int pulse_asleep, int pulse_awake)
219 if (pulse_speed > 510)
224 pulse_asleep = !!pulse_asleep;
225 pulse_awake = !!pulse_awake;
228 spin_lock_irqsave(&pm->lock, flags);
230 /* mark state updates which are required */
231 if (static_brightness != pm->static_brightness){
232 pm->static_brightness = static_brightness;
233 pm->requires_update |= UPDATE_STATIC_BRIGHTNESS;
235 if (pulse_asleep != pm->pulse_asleep){
236 pm->pulse_asleep = pulse_asleep;
237 pm->requires_update |= (UPDATE_PULSE_ASLEEP | UPDATE_STATIC_BRIGHTNESS);
239 if (pulse_awake != pm->pulse_awake){
240 pm->pulse_awake = pulse_awake;
241 pm->requires_update |= (UPDATE_PULSE_AWAKE | UPDATE_STATIC_BRIGHTNESS);
243 if (pulse_speed != pm->pulse_speed || pulse_table != pm->pulse_table){
244 pm->pulse_speed = pulse_speed;
245 pm->pulse_table = pulse_table;
246 pm->requires_update |= UPDATE_PULSE_MODE;
249 powermate_sync_state(pm);
251 spin_unlock_irqrestore(&pm->lock, flags);
254 /* Callback from the Input layer when an event arrives from userspace to configure the LED */
255 static int powermate_input_event(struct input_dev *dev, unsigned int type, unsigned int code, int _value)
257 unsigned int command = (unsigned int)_value;
258 struct powermate_device *pm = dev->private;
260 if (type == EV_MSC && code == MSC_PULSELED){
262 bits 0- 7: 8 bits: LED brightness
263 bits 8-16: 9 bits: pulsing speed modifier (0 ... 510); 0-254 = slower, 255 = standard, 256-510 = faster.
264 bits 17-18: 2 bits: pulse table (0, 1, 2 valid)
265 bit 19: 1 bit : pulse whilst asleep?
266 bit 20: 1 bit : pulse constantly?
268 int static_brightness = command & 0xFF; // bits 0-7
269 int pulse_speed = (command >> 8) & 0x1FF; // bits 8-16
270 int pulse_table = (command >> 17) & 0x3; // bits 17-18
271 int pulse_asleep = (command >> 19) & 0x1; // bit 19
272 int pulse_awake = (command >> 20) & 0x1; // bit 20
274 powermate_pulse_led(pm, static_brightness, pulse_speed, pulse_table, pulse_asleep, pulse_awake);
280 static int powermate_alloc_buffers(struct usb_device *udev, struct powermate_device *pm)
282 pm->data = usb_buffer_alloc(udev, POWERMATE_PAYLOAD_SIZE_MAX,
283 SLAB_ATOMIC, &pm->data_dma);
286 pm->configcr = usb_buffer_alloc(udev, sizeof(*(pm->configcr)),
287 SLAB_ATOMIC, &pm->configcr_dma);
294 static void powermate_free_buffers(struct usb_device *udev, struct powermate_device *pm)
297 usb_buffer_free(udev, POWERMATE_PAYLOAD_SIZE_MAX,
298 pm->data, pm->data_dma);
300 usb_buffer_free(udev, sizeof(*(pm->configcr)),
301 pm->configcr, pm->configcr_dma);
304 /* Called whenever a USB device matching one in our supported devices table is connected */
305 static int powermate_probe(struct usb_interface *intf, const struct usb_device_id *id)
307 struct usb_device *udev = interface_to_usbdev (intf);
308 struct usb_host_interface *interface;
309 struct usb_endpoint_descriptor *endpoint;
310 struct powermate_device *pm;
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 if (!(pm = kmalloc(sizeof(struct powermate_device), GFP_KERNEL)))
329 memset(pm, 0, sizeof(struct powermate_device));
332 if (powermate_alloc_buffers(udev, pm)) {
333 powermate_free_buffers(udev, pm);
338 pm->irq = usb_alloc_urb(0, GFP_KERNEL);
340 powermate_free_buffers(udev, pm);
345 pm->config = usb_alloc_urb(0, GFP_KERNEL);
347 usb_free_urb(pm->irq);
348 powermate_free_buffers(udev, pm);
353 spin_lock_init(&pm->lock);
354 init_input_dev(&pm->input);
356 /* get a handle to the interrupt data pipe */
357 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
358 maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
360 if(maxp < POWERMATE_PAYLOAD_SIZE_MIN || maxp > POWERMATE_PAYLOAD_SIZE_MAX){
361 printk("powermate: Expected payload of %d--%d bytes, found %d bytes!\n",
362 POWERMATE_PAYLOAD_SIZE_MIN, POWERMATE_PAYLOAD_SIZE_MAX, maxp);
363 maxp = POWERMATE_PAYLOAD_SIZE_MAX;
366 usb_fill_int_urb(pm->irq, udev, pipe, pm->data,
368 pm, endpoint->bInterval);
369 pm->irq->transfer_dma = pm->data_dma;
370 pm->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
372 /* register our interrupt URB with the USB system */
373 if (usb_submit_urb(pm->irq, GFP_KERNEL)) {
374 powermate_free_buffers(udev, pm);
376 return -EIO; /* failure */
379 switch (le16_to_cpu(udev->descriptor.idProduct)) {
380 case POWERMATE_PRODUCT_NEW: pm->input.name = pm_name_powermate; break;
381 case POWERMATE_PRODUCT_OLD: pm->input.name = pm_name_soundknob; break;
383 pm->input.name = pm_name_soundknob;
384 printk(KERN_WARNING "powermate: unknown product id %04x\n",
385 le16_to_cpu(udev->descriptor.idProduct));
388 pm->input.private = pm;
389 pm->input.evbit[0] = BIT(EV_KEY) | BIT(EV_REL) | BIT(EV_MSC);
390 pm->input.keybit[LONG(BTN_0)] = BIT(BTN_0);
391 pm->input.relbit[LONG(REL_DIAL)] = BIT(REL_DIAL);
392 pm->input.mscbit[LONG(MSC_PULSELED)] = BIT(MSC_PULSELED);
393 usb_to_input_id(udev, &pm->input.id);
394 pm->input.event = powermate_input_event;
395 pm->input.dev = &intf->dev;
396 pm->input.phys = pm->phys;
398 input_register_device(&pm->input);
400 usb_make_path(udev, path, 64);
401 snprintf(pm->phys, 64, "%s/input0", path);
402 printk(KERN_INFO "input: %s on %s\n", pm->input.name, pm->input.phys);
404 /* force an update of everything */
405 pm->requires_update = UPDATE_PULSE_ASLEEP | UPDATE_PULSE_AWAKE | UPDATE_PULSE_MODE | UPDATE_STATIC_BRIGHTNESS;
406 powermate_pulse_led(pm, 0x80, 255, 0, 1, 0); // set default pulse parameters
408 usb_set_intfdata(intf, pm);
412 /* Called when a USB device we've accepted ownership of is removed */
413 static void powermate_disconnect(struct usb_interface *intf)
415 struct powermate_device *pm = usb_get_intfdata (intf);
417 usb_set_intfdata(intf, NULL);
419 pm->requires_update = 0;
420 usb_kill_urb(pm->irq);
421 input_unregister_device(&pm->input);
422 usb_free_urb(pm->irq);
423 usb_free_urb(pm->config);
424 powermate_free_buffers(interface_to_usbdev(intf), pm);
430 static 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 */
437 MODULE_DEVICE_TABLE (usb, powermate_devices);
439 static struct usb_driver powermate_driver = {
440 .owner = THIS_MODULE,
442 .probe = powermate_probe,
443 .disconnect = powermate_disconnect,
444 .id_table = powermate_devices,
447 static int __init powermate_init(void)
449 return usb_register(&powermate_driver);
452 static void __exit powermate_cleanup(void)
454 usb_deregister(&powermate_driver);
457 module_init(powermate_init);
458 module_exit(powermate_cleanup);
460 MODULE_AUTHOR( "William R Sowerbutts" );
461 MODULE_DESCRIPTION( "Griffin Technology, Inc PowerMate driver" );
462 MODULE_LICENSE("GPL");