xref: /openbmc/linux/drivers/input/misc/powermate.c (revision 7587eb18)
1 /*
2  * A driver for the Griffin Technology, Inc. "PowerMate" USB controller dial.
3  *
4  * v1.1, (c)2002 William R Sowerbutts <will@sowerbutts.com>
5  *
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.
11  *
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.
21  *
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.
24  *
25  * Griffin were very happy to provide documentation and free hardware for development.
26  *
27  * Some userspace tools are available on the web: http://sowerbutts.com/powermate/
28  *
29  */
30 
31 #include <linux/kernel.h>
32 #include <linux/slab.h>
33 #include <linux/module.h>
34 #include <linux/spinlock.h>
35 #include <linux/usb/input.h>
36 
37 #define POWERMATE_VENDOR	0x077d	/* Griffin Technology, Inc. */
38 #define POWERMATE_PRODUCT_NEW	0x0410	/* Griffin PowerMate */
39 #define POWERMATE_PRODUCT_OLD	0x04AA	/* Griffin soundKnob */
40 
41 #define CONTOUR_VENDOR		0x05f3	/* Contour Design, Inc. */
42 #define CONTOUR_JOG		0x0240	/* Jog and Shuttle */
43 
44 /* these are the command codes we send to the device */
45 #define SET_STATIC_BRIGHTNESS  0x01
46 #define SET_PULSE_ASLEEP       0x02
47 #define SET_PULSE_AWAKE        0x03
48 #define SET_PULSE_MODE         0x04
49 
50 /* these refer to bits in the powermate_device's requires_update field. */
51 #define UPDATE_STATIC_BRIGHTNESS (1<<0)
52 #define UPDATE_PULSE_ASLEEP      (1<<1)
53 #define UPDATE_PULSE_AWAKE       (1<<2)
54 #define UPDATE_PULSE_MODE        (1<<3)
55 
56 /* at least two versions of the hardware exist, with differing payload
57    sizes. the first three bytes always contain the "interesting" data in
58    the relevant format. */
59 #define POWERMATE_PAYLOAD_SIZE_MAX 6
60 #define POWERMATE_PAYLOAD_SIZE_MIN 3
61 struct powermate_device {
62 	signed char *data;
63 	dma_addr_t data_dma;
64 	struct urb *irq, *config;
65 	struct usb_ctrlrequest *configcr;
66 	struct usb_device *udev;
67 	struct usb_interface *intf;
68 	struct input_dev *input;
69 	spinlock_t lock;
70 	int static_brightness;
71 	int pulse_speed;
72 	int pulse_table;
73 	int pulse_asleep;
74 	int pulse_awake;
75 	int requires_update; // physical settings which are out of sync
76 	char phys[64];
77 };
78 
79 static char pm_name_powermate[] = "Griffin PowerMate";
80 static char pm_name_soundknob[] = "Griffin SoundKnob";
81 
82 static void powermate_config_complete(struct urb *urb);
83 
84 /* Callback for data arriving from the PowerMate over the USB interrupt pipe */
85 static void powermate_irq(struct urb *urb)
86 {
87 	struct powermate_device *pm = urb->context;
88 	struct device *dev = &pm->intf->dev;
89 	int retval;
90 
91 	switch (urb->status) {
92 	case 0:
93 		/* success */
94 		break;
95 	case -ECONNRESET:
96 	case -ENOENT:
97 	case -ESHUTDOWN:
98 		/* this urb is terminated, clean up */
99 		dev_dbg(dev, "%s - urb shutting down with status: %d\n",
100 			__func__, urb->status);
101 		return;
102 	default:
103 		dev_dbg(dev, "%s - nonzero urb status received: %d\n",
104 			__func__, urb->status);
105 		goto exit;
106 	}
107 
108 	/* handle updates to device state */
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);
112 
113 exit:
114 	retval = usb_submit_urb (urb, GFP_ATOMIC);
115 	if (retval)
116 		dev_err(dev, "%s - usb_submit_urb failed with result: %d\n",
117 			__func__, retval);
118 }
119 
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)
122 {
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 */
127 
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){
137 		int op, arg;
138 		/* the powermate takes an operation and an argument for its pulse algorithm.
139 		   the operation can be:
140 		   0: divide the speed
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).
145 
146 		   thus, several states are equivalent and are coalesced into one state.
147 
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).
152 
153 		   Only values of 'arg' quite close to 255 are particularly useful/spectacular.
154 		*/
155 		if (pm->pulse_speed < 255) {
156 			op = 0;                   // divide
157 			arg = 255 - pm->pulse_speed;
158 		} else if (pm->pulse_speed > 255) {
159 			op = 2;                   // multiply
160 			arg = pm->pulse_speed - 255;
161 		} else {
162 			op = 1;                   // normal speed
163 			arg = 0;                  // can be any value
164 		}
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;
172 	} else {
173 		printk(KERN_ERR "powermate: unknown update required");
174 		pm->requires_update = 0; /* fudge the bug */
175 		return;
176 	}
177 
178 /*	printk("powermate: %04x %04x\n", pm->configcr->wValue, pm->configcr->wIndex); */
179 
180 	pm->configcr->bRequestType = 0x41; /* vendor request */
181 	pm->configcr->bRequest = 0x01;
182 	pm->configcr->wLength = 0;
183 
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 
188 	if (usb_submit_urb(pm->config, GFP_ATOMIC))
189 		printk(KERN_ERR "powermate: usb_submit_urb(config) failed");
190 }
191 
192 /* Called when our asynchronous control message completes. We may need to issue another immediately */
193 static void powermate_config_complete(struct urb *urb)
194 {
195 	struct powermate_device *pm = urb->context;
196 	unsigned long flags;
197 
198 	if (urb->status)
199 		printk(KERN_ERR "powermate: config urb returned %d\n", urb->status);
200 
201 	spin_lock_irqsave(&pm->lock, flags);
202 	powermate_sync_state(pm);
203 	spin_unlock_irqrestore(&pm->lock, flags);
204 }
205 
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)
209 {
210 	unsigned long flags;
211 
212 	if (pulse_speed < 0)
213 		pulse_speed = 0;
214 	if (pulse_table < 0)
215 		pulse_table = 0;
216 	if (pulse_speed > 510)
217 		pulse_speed = 510;
218 	if (pulse_table > 2)
219 		pulse_table = 2;
220 
221 	pulse_asleep = !!pulse_asleep;
222 	pulse_awake = !!pulse_awake;
223 
224 
225 	spin_lock_irqsave(&pm->lock, flags);
226 
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;
231 	}
232 	if (pulse_asleep != pm->pulse_asleep) {
233 		pm->pulse_asleep = pulse_asleep;
234 		pm->requires_update |= (UPDATE_PULSE_ASLEEP | UPDATE_STATIC_BRIGHTNESS);
235 	}
236 	if (pulse_awake != pm->pulse_awake) {
237 		pm->pulse_awake = pulse_awake;
238 		pm->requires_update |= (UPDATE_PULSE_AWAKE | UPDATE_STATIC_BRIGHTNESS);
239 	}
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;
244 	}
245 
246 	powermate_sync_state(pm);
247 
248 	spin_unlock_irqrestore(&pm->lock, flags);
249 }
250 
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)
253 {
254 	unsigned int command = (unsigned int)_value;
255 	struct powermate_device *pm = input_get_drvdata(dev);
256 
257 	if (type == EV_MSC && code == MSC_PULSELED){
258 		/*
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?
264 		*/
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
270 
271 		powermate_pulse_led(pm, static_brightness, pulse_speed, pulse_table, pulse_asleep, pulse_awake);
272 	}
273 
274 	return 0;
275 }
276 
277 static int powermate_alloc_buffers(struct usb_device *udev, struct powermate_device *pm)
278 {
279 	pm->data = usb_alloc_coherent(udev, POWERMATE_PAYLOAD_SIZE_MAX,
280 				      GFP_ATOMIC, &pm->data_dma);
281 	if (!pm->data)
282 		return -1;
283 
284 	pm->configcr = kmalloc(sizeof(*(pm->configcr)), GFP_KERNEL);
285 	if (!pm->configcr)
286 		return -ENOMEM;
287 
288 	return 0;
289 }
290 
291 static void powermate_free_buffers(struct usb_device *udev, struct powermate_device *pm)
292 {
293 	usb_free_coherent(udev, POWERMATE_PAYLOAD_SIZE_MAX,
294 			  pm->data, pm->data_dma);
295 	kfree(pm->configcr);
296 }
297 
298 /* Called whenever a USB device matching one in our supported devices table is connected */
299 static int powermate_probe(struct usb_interface *intf, const struct usb_device_id *id)
300 {
301 	struct usb_device *udev = interface_to_usbdev (intf);
302 	struct usb_host_interface *interface;
303 	struct usb_endpoint_descriptor *endpoint;
304 	struct powermate_device *pm;
305 	struct input_dev *input_dev;
306 	int pipe, maxp;
307 	int error = -ENOMEM;
308 
309 	interface = intf->cur_altsetting;
310 	if (interface->desc.bNumEndpoints < 1)
311 		return -EINVAL;
312 
313 	endpoint = &interface->endpoint[0].desc;
314 	if (!usb_endpoint_is_int_in(endpoint))
315 		return -EIO;
316 
317 	usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
318 		0x0a, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
319 		0, interface->desc.bInterfaceNumber, NULL, 0,
320 		USB_CTRL_SET_TIMEOUT);
321 
322 	pm = kzalloc(sizeof(struct powermate_device), GFP_KERNEL);
323 	input_dev = input_allocate_device();
324 	if (!pm || !input_dev)
325 		goto fail1;
326 
327 	if (powermate_alloc_buffers(udev, pm))
328 		goto fail2;
329 
330 	pm->irq = usb_alloc_urb(0, GFP_KERNEL);
331 	if (!pm->irq)
332 		goto fail2;
333 
334 	pm->config = usb_alloc_urb(0, GFP_KERNEL);
335 	if (!pm->config)
336 		goto fail3;
337 
338 	pm->udev = udev;
339 	pm->intf = intf;
340 	pm->input = input_dev;
341 
342 	usb_make_path(udev, pm->phys, sizeof(pm->phys));
343 	strlcat(pm->phys, "/input0", sizeof(pm->phys));
344 
345 	spin_lock_init(&pm->lock);
346 
347 	switch (le16_to_cpu(udev->descriptor.idProduct)) {
348 	case POWERMATE_PRODUCT_NEW:
349 		input_dev->name = pm_name_powermate;
350 		break;
351 	case POWERMATE_PRODUCT_OLD:
352 		input_dev->name = pm_name_soundknob;
353 		break;
354 	default:
355 		input_dev->name = pm_name_soundknob;
356 		printk(KERN_WARNING "powermate: unknown product id %04x\n",
357 		       le16_to_cpu(udev->descriptor.idProduct));
358 	}
359 
360 	input_dev->phys = pm->phys;
361 	usb_to_input_id(udev, &input_dev->id);
362 	input_dev->dev.parent = &intf->dev;
363 
364 	input_set_drvdata(input_dev, pm);
365 
366 	input_dev->event = powermate_input_event;
367 
368 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) |
369 		BIT_MASK(EV_MSC);
370 	input_dev->keybit[BIT_WORD(BTN_0)] = BIT_MASK(BTN_0);
371 	input_dev->relbit[BIT_WORD(REL_DIAL)] = BIT_MASK(REL_DIAL);
372 	input_dev->mscbit[BIT_WORD(MSC_PULSELED)] = BIT_MASK(MSC_PULSELED);
373 
374 	/* get a handle to the interrupt data pipe */
375 	pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
376 	maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
377 
378 	if (maxp < POWERMATE_PAYLOAD_SIZE_MIN || maxp > POWERMATE_PAYLOAD_SIZE_MAX) {
379 		printk(KERN_WARNING "powermate: Expected payload of %d--%d bytes, found %d bytes!\n",
380 			POWERMATE_PAYLOAD_SIZE_MIN, POWERMATE_PAYLOAD_SIZE_MAX, maxp);
381 		maxp = POWERMATE_PAYLOAD_SIZE_MAX;
382 	}
383 
384 	usb_fill_int_urb(pm->irq, udev, pipe, pm->data,
385 			 maxp, powermate_irq,
386 			 pm, endpoint->bInterval);
387 	pm->irq->transfer_dma = pm->data_dma;
388 	pm->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
389 
390 	/* register our interrupt URB with the USB system */
391 	if (usb_submit_urb(pm->irq, GFP_KERNEL)) {
392 		error = -EIO;
393 		goto fail4;
394 	}
395 
396 	error = input_register_device(pm->input);
397 	if (error)
398 		goto fail5;
399 
400 
401 	/* force an update of everything */
402 	pm->requires_update = UPDATE_PULSE_ASLEEP | UPDATE_PULSE_AWAKE | UPDATE_PULSE_MODE | UPDATE_STATIC_BRIGHTNESS;
403 	powermate_pulse_led(pm, 0x80, 255, 0, 1, 0); // set default pulse parameters
404 
405 	usb_set_intfdata(intf, pm);
406 	return 0;
407 
408  fail5:	usb_kill_urb(pm->irq);
409  fail4:	usb_free_urb(pm->config);
410  fail3:	usb_free_urb(pm->irq);
411  fail2:	powermate_free_buffers(udev, pm);
412  fail1:	input_free_device(input_dev);
413 	kfree(pm);
414 	return error;
415 }
416 
417 /* Called when a USB device we've accepted ownership of is removed */
418 static void powermate_disconnect(struct usb_interface *intf)
419 {
420 	struct powermate_device *pm = usb_get_intfdata (intf);
421 
422 	usb_set_intfdata(intf, NULL);
423 	if (pm) {
424 		pm->requires_update = 0;
425 		usb_kill_urb(pm->irq);
426 		input_unregister_device(pm->input);
427 		usb_free_urb(pm->irq);
428 		usb_free_urb(pm->config);
429 		powermate_free_buffers(interface_to_usbdev(intf), pm);
430 
431 		kfree(pm);
432 	}
433 }
434 
435 static struct usb_device_id powermate_devices [] = {
436 	{ USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_NEW) },
437 	{ USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_OLD) },
438 	{ USB_DEVICE(CONTOUR_VENDOR, CONTOUR_JOG) },
439 	{ } /* Terminating entry */
440 };
441 
442 MODULE_DEVICE_TABLE (usb, powermate_devices);
443 
444 static struct usb_driver powermate_driver = {
445         .name =         "powermate",
446         .probe =        powermate_probe,
447         .disconnect =   powermate_disconnect,
448         .id_table =     powermate_devices,
449 };
450 
451 module_usb_driver(powermate_driver);
452 
453 MODULE_AUTHOR( "William R Sowerbutts" );
454 MODULE_DESCRIPTION( "Griffin Technology, Inc PowerMate driver" );
455 MODULE_LICENSE("GPL");
456