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v4.6
  1/*
  2 * Xen para-virtual input device
  3 *
  4 * Copyright (C) 2005 Anthony Liguori <aliguori@us.ibm.com>
  5 * Copyright (C) 2006-2008 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
  6 *
  7 *  Based on linux/drivers/input/mouse/sermouse.c
  8 *
  9 *  This file is subject to the terms and conditions of the GNU General Public
 10 *  License. See the file COPYING in the main directory of this archive for
 11 *  more details.
 12 */
 13
 14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 15
 16#include <linux/kernel.h>
 17#include <linux/errno.h>
 18#include <linux/module.h>
 19#include <linux/input.h>
 20#include <linux/slab.h>
 21
 22#include <asm/xen/hypervisor.h>
 23
 24#include <xen/xen.h>
 25#include <xen/events.h>
 26#include <xen/page.h>
 27#include <xen/grant_table.h>
 28#include <xen/interface/grant_table.h>
 29#include <xen/interface/io/fbif.h>
 30#include <xen/interface/io/kbdif.h>
 31#include <xen/xenbus.h>
 32#include <xen/platform_pci.h>
 33
 34struct xenkbd_info {
 35	struct input_dev *kbd;
 36	struct input_dev *ptr;
 37	struct xenkbd_page *page;
 38	int gref;
 39	int irq;
 40	struct xenbus_device *xbdev;
 41	char phys[32];
 42};
 43
 44static int xenkbd_remove(struct xenbus_device *);
 45static int xenkbd_connect_backend(struct xenbus_device *, struct xenkbd_info *);
 46static void xenkbd_disconnect_backend(struct xenkbd_info *);
 47
 48/*
 49 * Note: if you need to send out events, see xenfb_do_update() for how
 50 * to do that.
 51 */
 52
 53static irqreturn_t input_handler(int rq, void *dev_id)
 54{
 55	struct xenkbd_info *info = dev_id;
 56	struct xenkbd_page *page = info->page;
 57	__u32 cons, prod;
 58
 59	prod = page->in_prod;
 60	if (prod == page->in_cons)
 61		return IRQ_HANDLED;
 62	rmb();			/* ensure we see ring contents up to prod */
 63	for (cons = page->in_cons; cons != prod; cons++) {
 64		union xenkbd_in_event *event;
 65		struct input_dev *dev;
 66		event = &XENKBD_IN_RING_REF(page, cons);
 67
 68		dev = info->ptr;
 69		switch (event->type) {
 70		case XENKBD_TYPE_MOTION:
 71			input_report_rel(dev, REL_X, event->motion.rel_x);
 72			input_report_rel(dev, REL_Y, event->motion.rel_y);
 73			if (event->motion.rel_z)
 74				input_report_rel(dev, REL_WHEEL,
 75						 -event->motion.rel_z);
 76			break;
 77		case XENKBD_TYPE_KEY:
 78			dev = NULL;
 79			if (test_bit(event->key.keycode, info->kbd->keybit))
 80				dev = info->kbd;
 81			if (test_bit(event->key.keycode, info->ptr->keybit))
 82				dev = info->ptr;
 83			if (dev)
 84				input_report_key(dev, event->key.keycode,
 85						 event->key.pressed);
 86			else
 87				pr_warning("unhandled keycode 0x%x\n",
 88					   event->key.keycode);
 89			break;
 90		case XENKBD_TYPE_POS:
 91			input_report_abs(dev, ABS_X, event->pos.abs_x);
 92			input_report_abs(dev, ABS_Y, event->pos.abs_y);
 93			if (event->pos.rel_z)
 94				input_report_rel(dev, REL_WHEEL,
 95						 -event->pos.rel_z);
 96			break;
 97		}
 98		if (dev)
 99			input_sync(dev);
100	}
101	mb();			/* ensure we got ring contents */
102	page->in_cons = cons;
103	notify_remote_via_irq(info->irq);
104
105	return IRQ_HANDLED;
106}
107
108static int xenkbd_probe(struct xenbus_device *dev,
109				  const struct xenbus_device_id *id)
110{
111	int ret, i, abs;
112	struct xenkbd_info *info;
113	struct input_dev *kbd, *ptr;
114
115	info = kzalloc(sizeof(*info), GFP_KERNEL);
116	if (!info) {
117		xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
118		return -ENOMEM;
119	}
120	dev_set_drvdata(&dev->dev, info);
121	info->xbdev = dev;
122	info->irq = -1;
123	info->gref = -1;
124	snprintf(info->phys, sizeof(info->phys), "xenbus/%s", dev->nodename);
125
126	info->page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
127	if (!info->page)
128		goto error_nomem;
129
130	if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-abs-pointer", "%d", &abs) < 0)
131		abs = 0;
132	if (abs) {
133		ret = xenbus_printf(XBT_NIL, dev->nodename,
134				    "request-abs-pointer", "1");
135		if (ret) {
136			pr_warning("xenkbd: can't request abs-pointer");
137			abs = 0;
138		}
139	}
140
141	/* keyboard */
142	kbd = input_allocate_device();
143	if (!kbd)
144		goto error_nomem;
145	kbd->name = "Xen Virtual Keyboard";
146	kbd->phys = info->phys;
147	kbd->id.bustype = BUS_PCI;
148	kbd->id.vendor = 0x5853;
149	kbd->id.product = 0xffff;
150
151	__set_bit(EV_KEY, kbd->evbit);
152	for (i = KEY_ESC; i < KEY_UNKNOWN; i++)
153		__set_bit(i, kbd->keybit);
154	for (i = KEY_OK; i < KEY_MAX; i++)
155		__set_bit(i, kbd->keybit);
156
157	ret = input_register_device(kbd);
158	if (ret) {
159		input_free_device(kbd);
160		xenbus_dev_fatal(dev, ret, "input_register_device(kbd)");
161		goto error;
162	}
163	info->kbd = kbd;
164
165	/* pointing device */
166	ptr = input_allocate_device();
167	if (!ptr)
168		goto error_nomem;
169	ptr->name = "Xen Virtual Pointer";
170	ptr->phys = info->phys;
171	ptr->id.bustype = BUS_PCI;
172	ptr->id.vendor = 0x5853;
173	ptr->id.product = 0xfffe;
174
175	if (abs) {
176		__set_bit(EV_ABS, ptr->evbit);
177		input_set_abs_params(ptr, ABS_X, 0, XENFB_WIDTH, 0, 0);
178		input_set_abs_params(ptr, ABS_Y, 0, XENFB_HEIGHT, 0, 0);
179	} else {
180		input_set_capability(ptr, EV_REL, REL_X);
181		input_set_capability(ptr, EV_REL, REL_Y);
182	}
183	input_set_capability(ptr, EV_REL, REL_WHEEL);
184
185	__set_bit(EV_KEY, ptr->evbit);
186	for (i = BTN_LEFT; i <= BTN_TASK; i++)
187		__set_bit(i, ptr->keybit);
188
189	ret = input_register_device(ptr);
190	if (ret) {
191		input_free_device(ptr);
192		xenbus_dev_fatal(dev, ret, "input_register_device(ptr)");
193		goto error;
194	}
195	info->ptr = ptr;
196
197	ret = xenkbd_connect_backend(dev, info);
198	if (ret < 0)
199		goto error;
200
201	return 0;
202
203 error_nomem:
204	ret = -ENOMEM;
205	xenbus_dev_fatal(dev, ret, "allocating device memory");
206 error:
207	xenkbd_remove(dev);
208	return ret;
209}
210
211static int xenkbd_resume(struct xenbus_device *dev)
212{
213	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
214
215	xenkbd_disconnect_backend(info);
216	memset(info->page, 0, PAGE_SIZE);
217	return xenkbd_connect_backend(dev, info);
218}
219
220static int xenkbd_remove(struct xenbus_device *dev)
221{
222	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
223
224	xenkbd_disconnect_backend(info);
225	if (info->kbd)
226		input_unregister_device(info->kbd);
227	if (info->ptr)
228		input_unregister_device(info->ptr);
229	free_page((unsigned long)info->page);
230	kfree(info);
231	return 0;
232}
233
234static int xenkbd_connect_backend(struct xenbus_device *dev,
235				  struct xenkbd_info *info)
236{
237	int ret, evtchn;
238	struct xenbus_transaction xbt;
239
240	ret = gnttab_grant_foreign_access(dev->otherend_id,
241	                                  virt_to_gfn(info->page), 0);
242	if (ret < 0)
243		return ret;
244	info->gref = ret;
245
246	ret = xenbus_alloc_evtchn(dev, &evtchn);
247	if (ret)
248		goto error_grant;
249	ret = bind_evtchn_to_irqhandler(evtchn, input_handler,
250					0, dev->devicetype, info);
251	if (ret < 0) {
252		xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
253		goto error_evtchan;
254	}
255	info->irq = ret;
256
257 again:
258	ret = xenbus_transaction_start(&xbt);
259	if (ret) {
260		xenbus_dev_fatal(dev, ret, "starting transaction");
261		goto error_irqh;
262	}
263	ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
264			    virt_to_gfn(info->page));
265	if (ret)
266		goto error_xenbus;
267	ret = xenbus_printf(xbt, dev->nodename, "page-gref", "%u", info->gref);
268	if (ret)
269		goto error_xenbus;
270	ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
271			    evtchn);
272	if (ret)
273		goto error_xenbus;
274	ret = xenbus_transaction_end(xbt, 0);
275	if (ret) {
276		if (ret == -EAGAIN)
277			goto again;
278		xenbus_dev_fatal(dev, ret, "completing transaction");
279		goto error_irqh;
280	}
281
282	xenbus_switch_state(dev, XenbusStateInitialised);
283	return 0;
284
285 error_xenbus:
286	xenbus_transaction_end(xbt, 1);
287	xenbus_dev_fatal(dev, ret, "writing xenstore");
288 error_irqh:
289	unbind_from_irqhandler(info->irq, info);
290	info->irq = -1;
291 error_evtchan:
292	xenbus_free_evtchn(dev, evtchn);
293 error_grant:
294	gnttab_end_foreign_access(info->gref, 0, 0UL);
295	info->gref = -1;
296	return ret;
297}
298
299static void xenkbd_disconnect_backend(struct xenkbd_info *info)
300{
301	if (info->irq >= 0)
302		unbind_from_irqhandler(info->irq, info);
303	info->irq = -1;
304	if (info->gref >= 0)
305		gnttab_end_foreign_access(info->gref, 0, 0UL);
306	info->gref = -1;
307}
308
309static void xenkbd_backend_changed(struct xenbus_device *dev,
310				   enum xenbus_state backend_state)
311{
312	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
313	int ret, val;
314
315	switch (backend_state) {
316	case XenbusStateInitialising:
317	case XenbusStateInitialised:
318	case XenbusStateReconfiguring:
319	case XenbusStateReconfigured:
320	case XenbusStateUnknown:
 
321		break;
322
323	case XenbusStateInitWait:
324InitWait:
325		ret = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
326				   "feature-abs-pointer", "%d", &val);
327		if (ret < 0)
328			val = 0;
329		if (val) {
330			ret = xenbus_printf(XBT_NIL, info->xbdev->nodename,
331					    "request-abs-pointer", "1");
332			if (ret)
333				pr_warning("xenkbd: can't request abs-pointer");
334		}
335
336		xenbus_switch_state(dev, XenbusStateConnected);
337		break;
338
339	case XenbusStateConnected:
340		/*
341		 * Work around xenbus race condition: If backend goes
342		 * through InitWait to Connected fast enough, we can
343		 * get Connected twice here.
344		 */
345		if (dev->state != XenbusStateConnected)
346			goto InitWait; /* no InitWait seen yet, fudge it */
347
348		/* Set input abs params to match backend screen res */
349		if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
350				 "width", "%d", &val) > 0)
351			input_set_abs_params(info->ptr, ABS_X, 0, val, 0, 0);
352
353		if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
354				 "height", "%d", &val) > 0)
355			input_set_abs_params(info->ptr, ABS_Y, 0, val, 0, 0);
356
357		break;
358
359	case XenbusStateClosed:
360		if (dev->state == XenbusStateClosed)
361			break;
362		/* Missed the backend's CLOSING state -- fallthrough */
363	case XenbusStateClosing:
364		xenbus_frontend_closed(dev);
365		break;
366	}
367}
368
369static const struct xenbus_device_id xenkbd_ids[] = {
370	{ "vkbd" },
371	{ "" }
372};
373
374static struct xenbus_driver xenkbd_driver = {
 
 
375	.ids = xenkbd_ids,
376	.probe = xenkbd_probe,
377	.remove = xenkbd_remove,
378	.resume = xenkbd_resume,
379	.otherend_changed = xenkbd_backend_changed,
380};
381
382static int __init xenkbd_init(void)
383{
384	if (!xen_domain())
385		return -ENODEV;
386
387	/* Nothing to do if running in dom0. */
388	if (xen_initial_domain())
389		return -ENODEV;
390
391	if (!xen_has_pv_devices())
392		return -ENODEV;
393
394	return xenbus_register_frontend(&xenkbd_driver);
395}
396
397static void __exit xenkbd_cleanup(void)
398{
399	xenbus_unregister_driver(&xenkbd_driver);
400}
401
402module_init(xenkbd_init);
403module_exit(xenkbd_cleanup);
404
405MODULE_DESCRIPTION("Xen virtual keyboard/pointer device frontend");
406MODULE_LICENSE("GPL");
407MODULE_ALIAS("xen:vkbd");
v3.1
  1/*
  2 * Xen para-virtual input device
  3 *
  4 * Copyright (C) 2005 Anthony Liguori <aliguori@us.ibm.com>
  5 * Copyright (C) 2006-2008 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
  6 *
  7 *  Based on linux/drivers/input/mouse/sermouse.c
  8 *
  9 *  This file is subject to the terms and conditions of the GNU General Public
 10 *  License. See the file COPYING in the main directory of this archive for
 11 *  more details.
 12 */
 13
 14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 15
 16#include <linux/kernel.h>
 17#include <linux/errno.h>
 18#include <linux/module.h>
 19#include <linux/input.h>
 20#include <linux/slab.h>
 21
 22#include <asm/xen/hypervisor.h>
 23
 24#include <xen/xen.h>
 25#include <xen/events.h>
 26#include <xen/page.h>
 27#include <xen/grant_table.h>
 28#include <xen/interface/grant_table.h>
 29#include <xen/interface/io/fbif.h>
 30#include <xen/interface/io/kbdif.h>
 31#include <xen/xenbus.h>
 
 32
 33struct xenkbd_info {
 34	struct input_dev *kbd;
 35	struct input_dev *ptr;
 36	struct xenkbd_page *page;
 37	int gref;
 38	int irq;
 39	struct xenbus_device *xbdev;
 40	char phys[32];
 41};
 42
 43static int xenkbd_remove(struct xenbus_device *);
 44static int xenkbd_connect_backend(struct xenbus_device *, struct xenkbd_info *);
 45static void xenkbd_disconnect_backend(struct xenkbd_info *);
 46
 47/*
 48 * Note: if you need to send out events, see xenfb_do_update() for how
 49 * to do that.
 50 */
 51
 52static irqreturn_t input_handler(int rq, void *dev_id)
 53{
 54	struct xenkbd_info *info = dev_id;
 55	struct xenkbd_page *page = info->page;
 56	__u32 cons, prod;
 57
 58	prod = page->in_prod;
 59	if (prod == page->in_cons)
 60		return IRQ_HANDLED;
 61	rmb();			/* ensure we see ring contents up to prod */
 62	for (cons = page->in_cons; cons != prod; cons++) {
 63		union xenkbd_in_event *event;
 64		struct input_dev *dev;
 65		event = &XENKBD_IN_RING_REF(page, cons);
 66
 67		dev = info->ptr;
 68		switch (event->type) {
 69		case XENKBD_TYPE_MOTION:
 70			input_report_rel(dev, REL_X, event->motion.rel_x);
 71			input_report_rel(dev, REL_Y, event->motion.rel_y);
 72			if (event->motion.rel_z)
 73				input_report_rel(dev, REL_WHEEL,
 74						 -event->motion.rel_z);
 75			break;
 76		case XENKBD_TYPE_KEY:
 77			dev = NULL;
 78			if (test_bit(event->key.keycode, info->kbd->keybit))
 79				dev = info->kbd;
 80			if (test_bit(event->key.keycode, info->ptr->keybit))
 81				dev = info->ptr;
 82			if (dev)
 83				input_report_key(dev, event->key.keycode,
 84						 event->key.pressed);
 85			else
 86				pr_warning("unhandled keycode 0x%x\n",
 87					   event->key.keycode);
 88			break;
 89		case XENKBD_TYPE_POS:
 90			input_report_abs(dev, ABS_X, event->pos.abs_x);
 91			input_report_abs(dev, ABS_Y, event->pos.abs_y);
 92			if (event->pos.rel_z)
 93				input_report_rel(dev, REL_WHEEL,
 94						 -event->pos.rel_z);
 95			break;
 96		}
 97		if (dev)
 98			input_sync(dev);
 99	}
100	mb();			/* ensure we got ring contents */
101	page->in_cons = cons;
102	notify_remote_via_irq(info->irq);
103
104	return IRQ_HANDLED;
105}
106
107static int __devinit xenkbd_probe(struct xenbus_device *dev,
108				  const struct xenbus_device_id *id)
109{
110	int ret, i, abs;
111	struct xenkbd_info *info;
112	struct input_dev *kbd, *ptr;
113
114	info = kzalloc(sizeof(*info), GFP_KERNEL);
115	if (!info) {
116		xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
117		return -ENOMEM;
118	}
119	dev_set_drvdata(&dev->dev, info);
120	info->xbdev = dev;
121	info->irq = -1;
122	info->gref = -1;
123	snprintf(info->phys, sizeof(info->phys), "xenbus/%s", dev->nodename);
124
125	info->page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
126	if (!info->page)
127		goto error_nomem;
128
129	if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-abs-pointer", "%d", &abs) < 0)
130		abs = 0;
131	if (abs)
132		xenbus_printf(XBT_NIL, dev->nodename, "request-abs-pointer", "1");
 
 
 
 
 
 
133
134	/* keyboard */
135	kbd = input_allocate_device();
136	if (!kbd)
137		goto error_nomem;
138	kbd->name = "Xen Virtual Keyboard";
139	kbd->phys = info->phys;
140	kbd->id.bustype = BUS_PCI;
141	kbd->id.vendor = 0x5853;
142	kbd->id.product = 0xffff;
143
144	__set_bit(EV_KEY, kbd->evbit);
145	for (i = KEY_ESC; i < KEY_UNKNOWN; i++)
146		__set_bit(i, kbd->keybit);
147	for (i = KEY_OK; i < KEY_MAX; i++)
148		__set_bit(i, kbd->keybit);
149
150	ret = input_register_device(kbd);
151	if (ret) {
152		input_free_device(kbd);
153		xenbus_dev_fatal(dev, ret, "input_register_device(kbd)");
154		goto error;
155	}
156	info->kbd = kbd;
157
158	/* pointing device */
159	ptr = input_allocate_device();
160	if (!ptr)
161		goto error_nomem;
162	ptr->name = "Xen Virtual Pointer";
163	ptr->phys = info->phys;
164	ptr->id.bustype = BUS_PCI;
165	ptr->id.vendor = 0x5853;
166	ptr->id.product = 0xfffe;
167
168	if (abs) {
169		__set_bit(EV_ABS, ptr->evbit);
170		input_set_abs_params(ptr, ABS_X, 0, XENFB_WIDTH, 0, 0);
171		input_set_abs_params(ptr, ABS_Y, 0, XENFB_HEIGHT, 0, 0);
172	} else {
173		input_set_capability(ptr, EV_REL, REL_X);
174		input_set_capability(ptr, EV_REL, REL_Y);
175	}
176	input_set_capability(ptr, EV_REL, REL_WHEEL);
177
178	__set_bit(EV_KEY, ptr->evbit);
179	for (i = BTN_LEFT; i <= BTN_TASK; i++)
180		__set_bit(i, ptr->keybit);
181
182	ret = input_register_device(ptr);
183	if (ret) {
184		input_free_device(ptr);
185		xenbus_dev_fatal(dev, ret, "input_register_device(ptr)");
186		goto error;
187	}
188	info->ptr = ptr;
189
190	ret = xenkbd_connect_backend(dev, info);
191	if (ret < 0)
192		goto error;
193
194	return 0;
195
196 error_nomem:
197	ret = -ENOMEM;
198	xenbus_dev_fatal(dev, ret, "allocating device memory");
199 error:
200	xenkbd_remove(dev);
201	return ret;
202}
203
204static int xenkbd_resume(struct xenbus_device *dev)
205{
206	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
207
208	xenkbd_disconnect_backend(info);
209	memset(info->page, 0, PAGE_SIZE);
210	return xenkbd_connect_backend(dev, info);
211}
212
213static int xenkbd_remove(struct xenbus_device *dev)
214{
215	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
216
217	xenkbd_disconnect_backend(info);
218	if (info->kbd)
219		input_unregister_device(info->kbd);
220	if (info->ptr)
221		input_unregister_device(info->ptr);
222	free_page((unsigned long)info->page);
223	kfree(info);
224	return 0;
225}
226
227static int xenkbd_connect_backend(struct xenbus_device *dev,
228				  struct xenkbd_info *info)
229{
230	int ret, evtchn;
231	struct xenbus_transaction xbt;
232
233	ret = gnttab_grant_foreign_access(dev->otherend_id,
234	                                  virt_to_mfn(info->page), 0);
235	if (ret < 0)
236		return ret;
237	info->gref = ret;
238
239	ret = xenbus_alloc_evtchn(dev, &evtchn);
240	if (ret)
241		goto error_grant;
242	ret = bind_evtchn_to_irqhandler(evtchn, input_handler,
243					0, dev->devicetype, info);
244	if (ret < 0) {
245		xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
246		goto error_evtchan;
247	}
248	info->irq = ret;
249
250 again:
251	ret = xenbus_transaction_start(&xbt);
252	if (ret) {
253		xenbus_dev_fatal(dev, ret, "starting transaction");
254		goto error_irqh;
255	}
256	ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
257			    virt_to_mfn(info->page));
258	if (ret)
259		goto error_xenbus;
260	ret = xenbus_printf(xbt, dev->nodename, "page-gref", "%u", info->gref);
261	if (ret)
262		goto error_xenbus;
263	ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
264			    evtchn);
265	if (ret)
266		goto error_xenbus;
267	ret = xenbus_transaction_end(xbt, 0);
268	if (ret) {
269		if (ret == -EAGAIN)
270			goto again;
271		xenbus_dev_fatal(dev, ret, "completing transaction");
272		goto error_irqh;
273	}
274
275	xenbus_switch_state(dev, XenbusStateInitialised);
276	return 0;
277
278 error_xenbus:
279	xenbus_transaction_end(xbt, 1);
280	xenbus_dev_fatal(dev, ret, "writing xenstore");
281 error_irqh:
282	unbind_from_irqhandler(info->irq, info);
283	info->irq = -1;
284 error_evtchan:
285	xenbus_free_evtchn(dev, evtchn);
286 error_grant:
287	gnttab_end_foreign_access_ref(info->gref, 0);
288	info->gref = -1;
289	return ret;
290}
291
292static void xenkbd_disconnect_backend(struct xenkbd_info *info)
293{
294	if (info->irq >= 0)
295		unbind_from_irqhandler(info->irq, info);
296	info->irq = -1;
297	if (info->gref >= 0)
298		gnttab_end_foreign_access_ref(info->gref, 0);
299	info->gref = -1;
300}
301
302static void xenkbd_backend_changed(struct xenbus_device *dev,
303				   enum xenbus_state backend_state)
304{
305	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
306	int ret, val;
307
308	switch (backend_state) {
309	case XenbusStateInitialising:
310	case XenbusStateInitialised:
311	case XenbusStateReconfiguring:
312	case XenbusStateReconfigured:
313	case XenbusStateUnknown:
314	case XenbusStateClosed:
315		break;
316
317	case XenbusStateInitWait:
318InitWait:
319		ret = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
320				   "feature-abs-pointer", "%d", &val);
321		if (ret < 0)
322			val = 0;
323		if (val) {
324			ret = xenbus_printf(XBT_NIL, info->xbdev->nodename,
325					    "request-abs-pointer", "1");
326			if (ret)
327				pr_warning("xenkbd: can't request abs-pointer");
328		}
329
330		xenbus_switch_state(dev, XenbusStateConnected);
331		break;
332
333	case XenbusStateConnected:
334		/*
335		 * Work around xenbus race condition: If backend goes
336		 * through InitWait to Connected fast enough, we can
337		 * get Connected twice here.
338		 */
339		if (dev->state != XenbusStateConnected)
340			goto InitWait; /* no InitWait seen yet, fudge it */
341
342		/* Set input abs params to match backend screen res */
343		if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
344				 "width", "%d", &val) > 0)
345			input_set_abs_params(info->ptr, ABS_X, 0, val, 0, 0);
346
347		if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
348				 "height", "%d", &val) > 0)
349			input_set_abs_params(info->ptr, ABS_Y, 0, val, 0, 0);
350
351		break;
352
 
 
 
 
353	case XenbusStateClosing:
354		xenbus_frontend_closed(dev);
355		break;
356	}
357}
358
359static const struct xenbus_device_id xenkbd_ids[] = {
360	{ "vkbd" },
361	{ "" }
362};
363
364static struct xenbus_driver xenkbd_driver = {
365	.name = "vkbd",
366	.owner = THIS_MODULE,
367	.ids = xenkbd_ids,
368	.probe = xenkbd_probe,
369	.remove = xenkbd_remove,
370	.resume = xenkbd_resume,
371	.otherend_changed = xenkbd_backend_changed,
372};
373
374static int __init xenkbd_init(void)
375{
376	if (!xen_domain())
377		return -ENODEV;
378
379	/* Nothing to do if running in dom0. */
380	if (xen_initial_domain())
 
 
 
381		return -ENODEV;
382
383	return xenbus_register_frontend(&xenkbd_driver);
384}
385
386static void __exit xenkbd_cleanup(void)
387{
388	xenbus_unregister_driver(&xenkbd_driver);
389}
390
391module_init(xenkbd_init);
392module_exit(xenkbd_cleanup);
393
394MODULE_DESCRIPTION("Xen virtual keyboard/pointer device frontend");
395MODULE_LICENSE("GPL");
396MODULE_ALIAS("xen:vkbd");