xref: /linux/drivers/input/misc/powermate.c (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * A driver for the Griffin Technology, Inc. "PowerMate" USB controller dial.
4  *
5  * v1.1, (c)2002 William R Sowerbutts <will@sowerbutts.com>
6  *
7  * This device is a anodised aluminium knob which connects over USB. It can measure
8  * clockwise and anticlockwise rotation. The dial also acts as a pushbutton with
9  * a spring for automatic release. The base contains a pair of LEDs which illuminate
10  * the translucent base. It rotates without limit and reports its relative rotation
11  * back to the host when polled by the USB controller.
12  *
13  * Testing with the knob I have has shown that it measures approximately 94 "clicks"
14  * for one full rotation. Testing with my High Speed Rotation Actuator (ok, it was
15  * a variable speed cordless electric drill) has shown that the device can measure
16  * speeds of up to 7 clicks either clockwise or anticlockwise between pollings from
17  * the host. If it counts more than 7 clicks before it is polled, it will wrap back
18  * to zero and start counting again. This was at quite high speed, however, almost
19  * certainly faster than the human hand could turn it. Griffin say that it loses a
20  * pulse or two on a direction change; the granularity is so fine that I never
21  * noticed this in practice.
22  *
23  * The device's microcontroller can be programmed to set the LED to either a constant
24  * intensity, or to a rhythmic pulsing. Several patterns and speeds are available.
25  *
26  * Griffin were very happy to provide documentation and free hardware for development.
27  *
28  * Some userspace tools are available on the web: http://sowerbutts.com/powermate/
29  *
30  */
31 
32 #include <linux/kernel.h>
33 #include <linux/slab.h>
34 #include <linux/module.h>
35 #include <linux/spinlock.h>
36 #include <linux/usb/input.h>
37 
38 #define POWERMATE_VENDOR	0x077d	/* Griffin Technology, Inc. */
39 #define POWERMATE_PRODUCT_NEW	0x0410	/* Griffin PowerMate */
40 #define POWERMATE_PRODUCT_OLD	0x04AA	/* Griffin soundKnob */
41 
42 #define CONTOUR_VENDOR		0x05f3	/* Contour Design, Inc. */
43 #define CONTOUR_JOG		0x0240	/* Jog and Shuttle */
44 
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
50 
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)
56 
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 {
63 	signed char *data;
64 	dma_addr_t data_dma;
65 	struct urb *irq, *config;
66 	struct usb_ctrlrequest *configcr;
67 	struct usb_device *udev;
68 	struct usb_interface *intf;
69 	struct input_dev *input;
70 	spinlock_t lock;
71 	int static_brightness;
72 	int pulse_speed;
73 	int pulse_table;
74 	int pulse_asleep;
75 	int pulse_awake;
76 	int requires_update; // physical settings which are out of sync
77 	char phys[64];
78 };
79 
80 static char pm_name_powermate[] = "Griffin PowerMate";
81 static char pm_name_soundknob[] = "Griffin SoundKnob";
82 
83 static void powermate_config_complete(struct urb *urb);
84 
85 /* Callback for data arriving from the PowerMate over the USB interrupt pipe */
powermate_irq(struct urb * urb)86 static void powermate_irq(struct urb *urb)
87 {
88 	struct powermate_device *pm = urb->context;
89 	struct device *dev = &pm->intf->dev;
90 	int retval;
91 
92 	switch (urb->status) {
93 	case 0:
94 		/* success */
95 		break;
96 	case -ECONNRESET:
97 	case -ENOENT:
98 	case -ESHUTDOWN:
99 		/* this urb is terminated, clean up */
100 		dev_dbg(dev, "%s - urb shutting down with status: %d\n",
101 			__func__, urb->status);
102 		return;
103 	default:
104 		dev_dbg(dev, "%s - nonzero urb status received: %d\n",
105 			__func__, urb->status);
106 		goto exit;
107 	}
108 
109 	/* handle updates to device state */
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);
113 
114 exit:
115 	retval = usb_submit_urb (urb, GFP_ATOMIC);
116 	if (retval)
117 		dev_err(dev, "%s - usb_submit_urb failed with result: %d\n",
118 			__func__, retval);
119 }
120 
121 /* Decide if we need to issue a control message and do so. Must be called with pm->lock taken */
powermate_sync_state(struct powermate_device * pm)122 static void powermate_sync_state(struct powermate_device *pm)
123 {
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 */
128 
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){
138 		int op, arg;
139 		/* the powermate takes an operation and an argument for its pulse algorithm.
140 		   the operation can be:
141 		   0: divide the speed
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).
146 
147 		   thus, several states are equivalent and are coalesced into one state.
148 
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).
153 
154 		   Only values of 'arg' quite close to 255 are particularly useful/spectacular.
155 		*/
156 		if (pm->pulse_speed < 255) {
157 			op = 0;                   // divide
158 			arg = 255 - pm->pulse_speed;
159 		} else if (pm->pulse_speed > 255) {
160 			op = 2;                   // multiply
161 			arg = pm->pulse_speed - 255;
162 		} else {
163 			op = 1;                   // normal speed
164 			arg = 0;                  // can be any value
165 		}
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;
173 	} else {
174 		printk(KERN_ERR "powermate: unknown update required");
175 		pm->requires_update = 0; /* fudge the bug */
176 		return;
177 	}
178 
179 /*	printk("powermate: %04x %04x\n", pm->configcr->wValue, pm->configcr->wIndex); */
180 
181 	pm->configcr->bRequestType = 0x41; /* vendor request */
182 	pm->configcr->bRequest = 0x01;
183 	pm->configcr->wLength = 0;
184 
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 
189 	if (usb_submit_urb(pm->config, GFP_ATOMIC))
190 		printk(KERN_ERR "powermate: usb_submit_urb(config) failed");
191 }
192 
193 /* Called when our asynchronous control message completes. We may need to issue another immediately */
powermate_config_complete(struct urb * urb)194 static void powermate_config_complete(struct urb *urb)
195 {
196 	struct powermate_device *pm = urb->context;
197 	unsigned long flags;
198 
199 	if (urb->status)
200 		printk(KERN_ERR "powermate: config urb returned %d\n", urb->status);
201 
202 	spin_lock_irqsave(&pm->lock, flags);
203 	powermate_sync_state(pm);
204 	spin_unlock_irqrestore(&pm->lock, flags);
205 }
206 
207 /* Set the LED up as described and begin the sync with the hardware if required */
powermate_pulse_led(struct powermate_device * pm,int static_brightness,int pulse_speed,int pulse_table,int pulse_asleep,int pulse_awake)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)
210 {
211 	unsigned long flags;
212 
213 	if (pulse_speed < 0)
214 		pulse_speed = 0;
215 	if (pulse_table < 0)
216 		pulse_table = 0;
217 	if (pulse_speed > 510)
218 		pulse_speed = 510;
219 	if (pulse_table > 2)
220 		pulse_table = 2;
221 
222 	pulse_asleep = !!pulse_asleep;
223 	pulse_awake = !!pulse_awake;
224 
225 
226 	spin_lock_irqsave(&pm->lock, flags);
227 
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;
232 	}
233 	if (pulse_asleep != pm->pulse_asleep) {
234 		pm->pulse_asleep = pulse_asleep;
235 		pm->requires_update |= (UPDATE_PULSE_ASLEEP | UPDATE_STATIC_BRIGHTNESS);
236 	}
237 	if (pulse_awake != pm->pulse_awake) {
238 		pm->pulse_awake = pulse_awake;
239 		pm->requires_update |= (UPDATE_PULSE_AWAKE | UPDATE_STATIC_BRIGHTNESS);
240 	}
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;
245 	}
246 
247 	powermate_sync_state(pm);
248 
249 	spin_unlock_irqrestore(&pm->lock, flags);
250 }
251 
252 /* Callback from the Input layer when an event arrives from userspace to configure the LED */
powermate_input_event(struct input_dev * dev,unsigned int type,unsigned int code,int _value)253 static int powermate_input_event(struct input_dev *dev, unsigned int type, unsigned int code, int _value)
254 {
255 	unsigned int command = (unsigned int)_value;
256 	struct powermate_device *pm = input_get_drvdata(dev);
257 
258 	if (type == EV_MSC && code == MSC_PULSELED){
259 		/*
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?
265 		*/
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
271 
272 		powermate_pulse_led(pm, static_brightness, pulse_speed, pulse_table, pulse_asleep, pulse_awake);
273 	}
274 
275 	return 0;
276 }
277 
powermate_alloc_buffers(struct usb_device * udev,struct powermate_device * pm)278 static int powermate_alloc_buffers(struct usb_device *udev, struct powermate_device *pm)
279 {
280 	pm->data = usb_alloc_coherent(udev, POWERMATE_PAYLOAD_SIZE_MAX,
281 				      GFP_KERNEL, &pm->data_dma);
282 	if (!pm->data)
283 		return -1;
284 
285 	pm->configcr = kmalloc(sizeof(*(pm->configcr)), GFP_KERNEL);
286 	if (!pm->configcr)
287 		return -ENOMEM;
288 
289 	return 0;
290 }
291 
powermate_free_buffers(struct usb_device * udev,struct powermate_device * pm)292 static void powermate_free_buffers(struct usb_device *udev, struct powermate_device *pm)
293 {
294 	usb_free_coherent(udev, POWERMATE_PAYLOAD_SIZE_MAX,
295 			  pm->data, pm->data_dma);
296 	kfree(pm->configcr);
297 }
298 
299 /* Called whenever a USB device matching one in our supported devices table is connected */
powermate_probe(struct usb_interface * intf,const struct usb_device_id * id)300 static int powermate_probe(struct usb_interface *intf, const struct usb_device_id *id)
301 {
302 	struct usb_device *udev = interface_to_usbdev (intf);
303 	struct usb_host_interface *interface;
304 	struct usb_endpoint_descriptor *endpoint;
305 	struct powermate_device *pm;
306 	struct input_dev *input_dev;
307 	int pipe, maxp;
308 	int error = -ENOMEM;
309 
310 	interface = intf->cur_altsetting;
311 	if (interface->desc.bNumEndpoints < 1)
312 		return -EINVAL;
313 
314 	endpoint = &interface->endpoint[0].desc;
315 	if (!usb_endpoint_is_int_in(endpoint))
316 		return -EIO;
317 
318 	usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
319 		0x0a, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
320 		0, interface->desc.bInterfaceNumber, NULL, 0,
321 		USB_CTRL_SET_TIMEOUT);
322 
323 	pm = kzalloc(sizeof(*pm), GFP_KERNEL);
324 	input_dev = input_allocate_device();
325 	if (!pm || !input_dev)
326 		goto fail1;
327 
328 	if (powermate_alloc_buffers(udev, pm))
329 		goto fail2;
330 
331 	pm->irq = usb_alloc_urb(0, GFP_KERNEL);
332 	if (!pm->irq)
333 		goto fail2;
334 
335 	pm->config = usb_alloc_urb(0, GFP_KERNEL);
336 	if (!pm->config)
337 		goto fail3;
338 
339 	pm->udev = udev;
340 	pm->intf = intf;
341 	pm->input = input_dev;
342 
343 	usb_make_path(udev, pm->phys, sizeof(pm->phys));
344 	strlcat(pm->phys, "/input0", sizeof(pm->phys));
345 
346 	spin_lock_init(&pm->lock);
347 
348 	switch (le16_to_cpu(udev->descriptor.idProduct)) {
349 	case POWERMATE_PRODUCT_NEW:
350 		input_dev->name = pm_name_powermate;
351 		break;
352 	case POWERMATE_PRODUCT_OLD:
353 		input_dev->name = pm_name_soundknob;
354 		break;
355 	default:
356 		input_dev->name = pm_name_soundknob;
357 		printk(KERN_WARNING "powermate: unknown product id %04x\n",
358 		       le16_to_cpu(udev->descriptor.idProduct));
359 	}
360 
361 	input_dev->phys = pm->phys;
362 	usb_to_input_id(udev, &input_dev->id);
363 	input_dev->dev.parent = &intf->dev;
364 
365 	input_set_drvdata(input_dev, pm);
366 
367 	input_dev->event = powermate_input_event;
368 
369 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) |
370 		BIT_MASK(EV_MSC);
371 	input_dev->keybit[BIT_WORD(BTN_0)] = BIT_MASK(BTN_0);
372 	input_dev->relbit[BIT_WORD(REL_DIAL)] = BIT_MASK(REL_DIAL);
373 	input_dev->mscbit[BIT_WORD(MSC_PULSELED)] = BIT_MASK(MSC_PULSELED);
374 
375 	/* get a handle to the interrupt data pipe */
376 	pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
377 	maxp = usb_maxpacket(udev, pipe);
378 
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;
383 	}
384 
385 	usb_fill_int_urb(pm->irq, udev, pipe, pm->data,
386 			 maxp, powermate_irq,
387 			 pm, endpoint->bInterval);
388 	pm->irq->transfer_dma = pm->data_dma;
389 	pm->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
390 
391 	/* register our interrupt URB with the USB system */
392 	if (usb_submit_urb(pm->irq, GFP_KERNEL)) {
393 		error = -EIO;
394 		goto fail4;
395 	}
396 
397 	error = input_register_device(pm->input);
398 	if (error)
399 		goto fail5;
400 
401 
402 	/* force an update of everything */
403 	pm->requires_update = UPDATE_PULSE_ASLEEP | UPDATE_PULSE_AWAKE | UPDATE_PULSE_MODE | UPDATE_STATIC_BRIGHTNESS;
404 	powermate_pulse_led(pm, 0x80, 255, 0, 1, 0); // set default pulse parameters
405 
406 	usb_set_intfdata(intf, pm);
407 	return 0;
408 
409  fail5:	usb_kill_urb(pm->irq);
410  fail4:	usb_free_urb(pm->config);
411  fail3:	usb_free_urb(pm->irq);
412  fail2:	powermate_free_buffers(udev, pm);
413  fail1:	input_free_device(input_dev);
414 	kfree(pm);
415 	return error;
416 }
417 
418 /* Called when a USB device we've accepted ownership of is removed */
powermate_disconnect(struct usb_interface * intf)419 static void powermate_disconnect(struct usb_interface *intf)
420 {
421 	struct powermate_device *pm = usb_get_intfdata (intf);
422 
423 	usb_set_intfdata(intf, NULL);
424 	if (pm) {
425 		pm->requires_update = 0;
426 		usb_kill_urb(pm->irq);
427 		input_unregister_device(pm->input);
428 		usb_kill_urb(pm->config);
429 		usb_free_urb(pm->irq);
430 		usb_free_urb(pm->config);
431 		powermate_free_buffers(interface_to_usbdev(intf), pm);
432 
433 		kfree(pm);
434 	}
435 }
436 
437 static const struct usb_device_id powermate_devices[] = {
438 	{ USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_NEW) },
439 	{ USB_DEVICE(POWERMATE_VENDOR, POWERMATE_PRODUCT_OLD) },
440 	{ USB_DEVICE(CONTOUR_VENDOR, CONTOUR_JOG) },
441 	{ } /* Terminating entry */
442 };
443 
444 MODULE_DEVICE_TABLE (usb, powermate_devices);
445 
446 static struct usb_driver powermate_driver = {
447         .name =         "powermate",
448         .probe =        powermate_probe,
449         .disconnect =   powermate_disconnect,
450         .id_table =     powermate_devices,
451 };
452 
453 module_usb_driver(powermate_driver);
454 
455 MODULE_AUTHOR( "William R Sowerbutts" );
456 MODULE_DESCRIPTION( "Griffin Technology, Inc PowerMate driver" );
457 MODULE_LICENSE("GPL");
458