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>
39 #define POWERMATE_VENDOR 0x077d /* Griffin Technology, Inc. */
40 #define POWERMATE_PRODUCT_NEW 0x0410 /* Griffin PowerMate */
41 #define POWERMATE_PRODUCT_OLD 0x04AA /* Griffin soundKnob */
43 #define CONTOUR_VENDOR 0x05f3 /* Contour Design, Inc. */
44 #define CONTOUR_JOG 0x0240 /* Jog and Shuttle */
46 /* these are the command codes we send to the device */
47 #define SET_STATIC_BRIGHTNESS 0x01
48 #define SET_PULSE_ASLEEP 0x02
49 #define SET_PULSE_AWAKE 0x03
50 #define SET_PULSE_MODE 0x04
52 /* these refer to bits in the powermate_device's requires_update field. */
53 #define UPDATE_STATIC_BRIGHTNESS (1<<0)
54 #define UPDATE_PULSE_ASLEEP (1<<1)
55 #define UPDATE_PULSE_AWAKE (1<<2)
56 #define UPDATE_PULSE_MODE (1<<3)
58 /* at least two versions of the hardware exist, with differing payload
59 sizes. the first three bytes always contain the "interesting" data in
60 the relevant format. */
61 #define POWERMATE_PAYLOAD_SIZE_MAX 6
62 #define POWERMATE_PAYLOAD_SIZE_MIN 3
63 struct powermate_device {
66 struct urb *irq, *config;
67 struct usb_ctrlrequest *configcr;
68 dma_addr_t configcr_dma;
69 struct usb_device *udev;
70 struct input_dev input;
72 int static_brightness;
77 int requires_update; // physical settings which are out of sync
81 static char pm_name_powermate[] = "Griffin PowerMate";
82 static char pm_name_soundknob[] = "Griffin SoundKnob";
84 static void powermate_config_complete(struct urb *urb, struct pt_regs *regs);
86 /* Callback for data arriving from the PowerMate over the USB interrupt pipe */
87 static void powermate_irq(struct urb *urb, struct pt_regs *regs)
89 struct powermate_device *pm = urb->context;
92 switch (urb->status) {
99 /* this urb is terminated, clean up */
100 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
103 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
107 /* handle updates to device state */
108 input_regs(&pm->input, regs);
109 input_report_key(&pm->input, BTN_0, pm->data[0] & 0x01);
110 input_report_rel(&pm->input, REL_DIAL, pm->data[1]);
111 input_sync(&pm->input);
114 retval = usb_submit_urb (urb, GFP_ATOMIC);
116 err ("%s - usb_submit_urb failed with result %d",
117 __FUNCTION__, retval);
120 /* Decide if we need to issue a control message and do so. Must be called with pm->lock taken */
121 static void powermate_sync_state(struct powermate_device *pm)
123 if (pm->requires_update == 0)
124 return; /* no updates are required */
125 if (pm->config->status == -EINPROGRESS)
126 return; /* an update is already in progress; it'll issue this update when it completes */
128 if (pm->requires_update & UPDATE_PULSE_ASLEEP){
129 pm->configcr->wValue = cpu_to_le16( SET_PULSE_ASLEEP );
130 pm->configcr->wIndex = cpu_to_le16( pm->pulse_asleep ? 1 : 0 );
131 pm->requires_update &= ~UPDATE_PULSE_ASLEEP;
132 }else if (pm->requires_update & UPDATE_PULSE_AWAKE){
133 pm->configcr->wValue = cpu_to_le16( SET_PULSE_AWAKE );
134 pm->configcr->wIndex = cpu_to_le16( pm->pulse_awake ? 1 : 0 );
135 pm->requires_update &= ~UPDATE_PULSE_AWAKE;
136 }else if (pm->requires_update & UPDATE_PULSE_MODE){
138 /* the powermate takes an operation and an argument for its pulse algorithm.
139 the operation can be:
141 1: pulse at normal speed
142 2: multiply the speed
143 the argument only has an effect for operations 0 and 2, and ranges between
144 1 (least effect) to 255 (maximum effect).
146 thus, several states are equivalent and are coalesced into one state.
148 we map this onto a range from 0 to 510, with:
149 0 -- 254 -- use divide (0 = slowest)
150 255 -- use normal speed
151 256 -- 510 -- use multiple (510 = fastest).
153 Only values of 'arg' quite close to 255 are particularly useful/spectacular.
155 if (pm->pulse_speed < 255){
157 arg = 255 - pm->pulse_speed;
158 } else if (pm->pulse_speed > 255){
160 arg = pm->pulse_speed - 255;
162 op = 1; // normal speed
163 arg = 0; // can be any value
165 pm->configcr->wValue = cpu_to_le16( (pm->pulse_table << 8) | SET_PULSE_MODE );
166 pm->configcr->wIndex = cpu_to_le16( (arg << 8) | op );
167 pm->requires_update &= ~UPDATE_PULSE_MODE;
168 }else if (pm->requires_update & UPDATE_STATIC_BRIGHTNESS){
169 pm->configcr->wValue = cpu_to_le16( SET_STATIC_BRIGHTNESS );
170 pm->configcr->wIndex = cpu_to_le16( pm->static_brightness );
171 pm->requires_update &= ~UPDATE_STATIC_BRIGHTNESS;
173 printk(KERN_ERR "powermate: unknown update required");
174 pm->requires_update = 0; /* fudge the bug */
178 /* printk("powermate: %04x %04x\n", pm->configcr->wValue, pm->configcr->wIndex); */
180 pm->configcr->bRequestType = 0x41; /* vendor request */
181 pm->configcr->bRequest = 0x01;
182 pm->configcr->wLength = 0;
184 usb_fill_control_urb(pm->config, pm->udev, usb_sndctrlpipe(pm->udev, 0),
185 (void *) pm->configcr, NULL, 0,
186 powermate_config_complete, pm);
187 pm->config->setup_dma = pm->configcr_dma;
188 pm->config->transfer_flags |= URB_NO_SETUP_DMA_MAP;
190 if (usb_submit_urb(pm->config, GFP_ATOMIC))
191 printk(KERN_ERR "powermate: usb_submit_urb(config) failed");
194 /* Called when our asynchronous control message completes. We may need to issue another immediately */
195 static void powermate_config_complete(struct urb *urb, struct pt_regs *regs)
197 struct powermate_device *pm = urb->context;
201 printk(KERN_ERR "powermate: config urb returned %d\n", urb->status);
203 spin_lock_irqsave(&pm->lock, flags);
204 powermate_sync_state(pm);
205 spin_unlock_irqrestore(&pm->lock, flags);
208 /* Set the LED up as described and begin the sync with the hardware if required */
209 static void powermate_pulse_led(struct powermate_device *pm, int static_brightness, int pulse_speed,
210 int pulse_table, int pulse_asleep, int pulse_awake)
218 if (pulse_speed > 510)
223 pulse_asleep = !!pulse_asleep;
224 pulse_awake = !!pulse_awake;
227 spin_lock_irqsave(&pm->lock, flags);
229 /* mark state updates which are required */
230 if (static_brightness != pm->static_brightness){
231 pm->static_brightness = static_brightness;
232 pm->requires_update |= UPDATE_STATIC_BRIGHTNESS;
234 if (pulse_asleep != pm->pulse_asleep){
235 pm->pulse_asleep = pulse_asleep;
236 pm->requires_update |= (UPDATE_PULSE_ASLEEP | UPDATE_STATIC_BRIGHTNESS);
238 if (pulse_awake != pm->pulse_awake){
239 pm->pulse_awake = pulse_awake;
240 pm->requires_update |= (UPDATE_PULSE_AWAKE | UPDATE_STATIC_BRIGHTNESS);
242 if (pulse_speed != pm->pulse_speed || pulse_table != pm->pulse_table){
243 pm->pulse_speed = pulse_speed;
244 pm->pulse_table = pulse_table;
245 pm->requires_update |= UPDATE_PULSE_MODE;
248 powermate_sync_state(pm);
250 spin_unlock_irqrestore(&pm->lock, flags);
253 /* Callback from the Input layer when an event arrives from userspace to configure the LED */
254 static int powermate_input_event(struct input_dev *dev, unsigned int type, unsigned int code, int _value)
256 unsigned int command = (unsigned int)_value;
257 struct powermate_device *pm = dev->private;
259 if (type == EV_MSC && code == MSC_PULSELED){
261 bits 0- 7: 8 bits: LED brightness
262 bits 8-16: 9 bits: pulsing speed modifier (0 ... 510); 0-254 = slower, 255 = standard, 256-510 = faster.
263 bits 17-18: 2 bits: pulse table (0, 1, 2 valid)
264 bit 19: 1 bit : pulse whilst asleep?
265 bit 20: 1 bit : pulse constantly?
267 int static_brightness = command & 0xFF; // bits 0-7
268 int pulse_speed = (command >> 8) & 0x1FF; // bits 8-16
269 int pulse_table = (command >> 17) & 0x3; // bits 17-18
270 int pulse_asleep = (command >> 19) & 0x1; // bit 19
271 int pulse_awake = (command >> 20) & 0x1; // bit 20
273 powermate_pulse_led(pm, static_brightness, pulse_speed, pulse_table, pulse_asleep, pulse_awake);
279 static int powermate_alloc_buffers(struct usb_device *udev, struct powermate_device *pm)
281 pm->data = usb_buffer_alloc(udev, POWERMATE_PAYLOAD_SIZE_MAX,
282 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;
313 interface = intf->cur_altsetting;
314 endpoint = &interface->endpoint[0].desc;
315 if (!(endpoint->bEndpointAddress & 0x80))
317 if ((endpoint->bmAttributes & 3) != 3)
320 usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
321 0x0a, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
322 0, interface->desc.bInterfaceNumber, NULL, 0,
323 USB_CTRL_SET_TIMEOUT);
325 if (!(pm = kmalloc(sizeof(struct powermate_device), GFP_KERNEL)))
328 memset(pm, 0, sizeof(struct powermate_device));
331 if (powermate_alloc_buffers(udev, pm)) {
332 powermate_free_buffers(udev, pm);
337 pm->irq = usb_alloc_urb(0, GFP_KERNEL);
339 powermate_free_buffers(udev, pm);
344 pm->config = usb_alloc_urb(0, GFP_KERNEL);
346 usb_free_urb(pm->irq);
347 powermate_free_buffers(udev, pm);
352 spin_lock_init(&pm->lock);
353 init_input_dev(&pm->input);
355 /* get a handle to the interrupt data pipe */
356 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
357 maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
359 if(maxp < POWERMATE_PAYLOAD_SIZE_MIN || maxp > POWERMATE_PAYLOAD_SIZE_MAX){
360 printk("powermate: Expected payload of %d--%d bytes, found %d bytes!\n",
361 POWERMATE_PAYLOAD_SIZE_MIN, POWERMATE_PAYLOAD_SIZE_MAX, maxp);
362 maxp = POWERMATE_PAYLOAD_SIZE_MAX;
365 usb_fill_int_urb(pm->irq, udev, pipe, pm->data,
367 pm, endpoint->bInterval);
368 pm->irq->transfer_dma = pm->data_dma;
369 pm->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
371 /* register our interrupt URB with the USB system */
372 if (usb_submit_urb(pm->irq, GFP_KERNEL)) {
373 powermate_free_buffers(udev, pm);
375 return -EIO; /* failure */
378 switch (le16_to_cpu(udev->descriptor.idProduct)) {
379 case POWERMATE_PRODUCT_NEW: pm->input.name = pm_name_powermate; break;
380 case POWERMATE_PRODUCT_OLD: pm->input.name = pm_name_soundknob; break;
382 pm->input.name = pm_name_soundknob;
383 printk(KERN_WARNING "powermate: unknown product id %04x\n",
384 le16_to_cpu(udev->descriptor.idProduct));
387 pm->input.private = pm;
388 pm->input.evbit[0] = BIT(EV_KEY) | BIT(EV_REL) | BIT(EV_MSC);
389 pm->input.keybit[LONG(BTN_0)] = BIT(BTN_0);
390 pm->input.relbit[LONG(REL_DIAL)] = BIT(REL_DIAL);
391 pm->input.mscbit[LONG(MSC_PULSELED)] = BIT(MSC_PULSELED);
392 pm->input.id.bustype = BUS_USB;
393 pm->input.id.vendor = le16_to_cpu(udev->descriptor.idVendor);
394 pm->input.id.product = le16_to_cpu(udev->descriptor.idProduct);
395 pm->input.id.version = le16_to_cpu(udev->descriptor.bcdDevice);
396 pm->input.event = powermate_input_event;
397 pm->input.dev = &intf->dev;
398 pm->input.phys = pm->phys;
400 input_register_device(&pm->input);
402 usb_make_path(udev, path, 64);
403 snprintf(pm->phys, 64, "%s/input0", path);
404 printk(KERN_INFO "input: %s on %s\n", pm->input.name, pm->input.phys);
406 /* force an update of everything */
407 pm->requires_update = UPDATE_PULSE_ASLEEP | UPDATE_PULSE_AWAKE | UPDATE_PULSE_MODE | UPDATE_STATIC_BRIGHTNESS;
408 powermate_pulse_led(pm, 0x80, 255, 0, 1, 0); // set default pulse parameters
410 usb_set_intfdata(intf, pm);
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 = {
442 .owner = THIS_MODULE,
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");