drivers/input/xen-kbdfront.c - kernel/skids - Git at Google

 /*
  * Xen para-virtual input device
  *
  * Copyright (C) 2005 Anthony Liguori <aliguori@us.ibm.com>
  * Copyright (C) 2006-2008 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
  *
  *  Based on linux/drivers/input/mouse/sermouse.c
  *
  *  This file is subject to the terms and conditions of the GNU General Public
  *  License. See the file COPYING in the main directory of this archive for
  *  more details.
  */

 /*
  * TODO:
  *
  * Switch to grant tables together with xen-fbfront.c.
  */

 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/module.h>
 #include <linux/input.h>
 #include <linux/slab.h>

 #include <asm/xen/hypervisor.h>

 #include <xen/xen.h>
 #include <xen/events.h>
 #include <xen/page.h>
 #include <xen/interface/io/fbif.h>
 #include <xen/interface/io/kbdif.h>
 #include <xen/xenbus.h>

 struct xenkbd_info {
 	struct input_dev *kbd;
 	struct input_dev *ptr;
 	struct xenkbd_page *page;
 	int irq;
 	struct xenbus_device *xbdev;
 	char phys[32];
 };

 static int xenkbd_remove(struct xenbus_device *);
 static int xenkbd_connect_backend(struct xenbus_device *, struct xenkbd_info *);
 static void xenkbd_disconnect_backend(struct xenkbd_info *);

 /*
  * Note: if you need to send out events, see xenfb_do_update() for how
  * to do that.
  */

 static irqreturn_t input_handler(int rq, void *dev_id)
 {
 	struct xenkbd_info *info = dev_id;
 	struct xenkbd_page *page = info->page;
 	__u32 cons, prod;

 	prod = page->in_prod;
 	if (prod == page->in_cons)
 		return IRQ_HANDLED;
 	rmb();			/* ensure we see ring contents up to prod */
 	for (cons = page->in_cons; cons != prod; cons++) {
 		union xenkbd_in_event *event;
 		struct input_dev *dev;
 		event = &XENKBD_IN_RING_REF(page, cons);

 		dev = info->ptr;
 		switch (event->type) {
 		case XENKBD_TYPE_MOTION:
 			input_report_rel(dev, REL_X, event->motion.rel_x);
 			input_report_rel(dev, REL_Y, event->motion.rel_y);
 			if (event->motion.rel_z)
 				input_report_rel(dev, REL_WHEEL,
 						 -event->motion.rel_z);
 			break;
 		case XENKBD_TYPE_KEY:
 			dev = NULL;
 			if (test_bit(event->key.keycode, info->kbd->keybit))
 				dev = info->kbd;
 			if (test_bit(event->key.keycode, info->ptr->keybit))
 				dev = info->ptr;
 			if (dev)
 				input_report_key(dev, event->key.keycode,
 						 event->key.pressed);
 			else
 				printk(KERN_WARNING
 				       "xenkbd: unhandled keycode 0x%x\n",
 				       event->key.keycode);
 			break;
 		case XENKBD_TYPE_POS:
 			input_report_abs(dev, ABS_X, event->pos.abs_x);
 			input_report_abs(dev, ABS_Y, event->pos.abs_y);
 			if (event->pos.rel_z)
 				input_report_rel(dev, REL_WHEEL,
 						 -event->pos.rel_z);
 			break;
 		}
 		if (dev)
 			input_sync(dev);
 	}
 	mb();			/* ensure we got ring contents */
 	page->in_cons = cons;
 	notify_remote_via_irq(info->irq);

 	return IRQ_HANDLED;
 }

 static int __devinit xenkbd_probe(struct xenbus_device *dev,
 				  const struct xenbus_device_id *id)
 {
 	int ret, i, abs;
 	struct xenkbd_info *info;
 	struct input_dev *kbd, *ptr;

 	info = kzalloc(sizeof(*info), GFP_KERNEL);
 	if (!info) {
 		xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
 		return -ENOMEM;
 	}
 	dev_set_drvdata(&dev->dev, info);
 	info->xbdev = dev;
 	info->irq = -1;
 	snprintf(info->phys, sizeof(info->phys), "xenbus/%s", dev->nodename);

 	info->page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
 	if (!info->page)
 		goto error_nomem;

 	if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-abs-pointer", "%d", &abs) < 0)
 		abs = 0;
 	if (abs)
 		xenbus_printf(XBT_NIL, dev->nodename, "request-abs-pointer", "1");

 	/* keyboard */
 	kbd = input_allocate_device();
 	if (!kbd)
 		goto error_nomem;
 	kbd->name = "Xen Virtual Keyboard";
 	kbd->phys = info->phys;
 	kbd->id.bustype = BUS_PCI;
 	kbd->id.vendor = 0x5853;
 	kbd->id.product = 0xffff;

 	__set_bit(EV_KEY, kbd->evbit);
 	for (i = KEY_ESC; i < KEY_UNKNOWN; i++)
 		__set_bit(i, kbd->keybit);
 	for (i = KEY_OK; i < KEY_MAX; i++)
 		__set_bit(i, kbd->keybit);

 	ret = input_register_device(kbd);
 	if (ret) {
 		input_free_device(kbd);
 		xenbus_dev_fatal(dev, ret, "input_register_device(kbd)");
 		goto error;
 	}
 	info->kbd = kbd;

 	/* pointing device */
 	ptr = input_allocate_device();
 	if (!ptr)
 		goto error_nomem;
 	ptr->name = "Xen Virtual Pointer";
 	ptr->phys = info->phys;
 	ptr->id.bustype = BUS_PCI;
 	ptr->id.vendor = 0x5853;
 	ptr->id.product = 0xfffe;

 	if (abs) {
 		__set_bit(EV_ABS, ptr->evbit);
 		input_set_abs_params(ptr, ABS_X, 0, XENFB_WIDTH, 0, 0);
 		input_set_abs_params(ptr, ABS_Y, 0, XENFB_HEIGHT, 0, 0);
 	} else {
 		input_set_capability(ptr, EV_REL, REL_X);
 		input_set_capability(ptr, EV_REL, REL_Y);
 	}
 	input_set_capability(ptr, EV_REL, REL_WHEEL);

 	__set_bit(EV_KEY, ptr->evbit);
 	for (i = BTN_LEFT; i <= BTN_TASK; i++)
 		__set_bit(i, ptr->keybit);

 	ret = input_register_device(ptr);
 	if (ret) {
 		input_free_device(ptr);
 		xenbus_dev_fatal(dev, ret, "input_register_device(ptr)");
 		goto error;
 	}
 	info->ptr = ptr;

 	ret = xenkbd_connect_backend(dev, info);
 	if (ret < 0)
 		goto error;

 	return 0;

  error_nomem:
 	ret = -ENOMEM;
 	xenbus_dev_fatal(dev, ret, "allocating device memory");
  error:
 	xenkbd_remove(dev);
 	return ret;
 }

 static int xenkbd_resume(struct xenbus_device *dev)
 {
 	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);

 	xenkbd_disconnect_backend(info);
 	memset(info->page, 0, PAGE_SIZE);
 	return xenkbd_connect_backend(dev, info);
 }

 static int xenkbd_remove(struct xenbus_device *dev)
 {
 	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);

 	xenkbd_disconnect_backend(info);
 	if (info->kbd)
 		input_unregister_device(info->kbd);
 	if (info->ptr)
 		input_unregister_device(info->ptr);
 	free_page((unsigned long)info->page);
 	kfree(info);
 	return 0;
 }

 static int xenkbd_connect_backend(struct xenbus_device *dev,
 				  struct xenkbd_info *info)
 {
 	int ret, evtchn;
 	struct xenbus_transaction xbt;

 	ret = xenbus_alloc_evtchn(dev, &evtchn);
 	if (ret)
 		return ret;
 	ret = bind_evtchn_to_irqhandler(evtchn, input_handler,
 					0, dev->devicetype, info);
 	if (ret < 0) {
 		xenbus_free_evtchn(dev, evtchn);
 		xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
 		return ret;
 	}
 	info->irq = ret;

  again:
 	ret = xenbus_transaction_start(&xbt);
 	if (ret) {
 		xenbus_dev_fatal(dev, ret, "starting transaction");
 		return ret;
 	}
 	ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
 			    virt_to_mfn(info->page));
 	if (ret)
 		goto error_xenbus;
 	ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
 			    evtchn);
 	if (ret)
 		goto error_xenbus;
 	ret = xenbus_transaction_end(xbt, 0);
 	if (ret) {
 		if (ret == -EAGAIN)
 			goto again;
 		xenbus_dev_fatal(dev, ret, "completing transaction");
 		return ret;
 	}

 	xenbus_switch_state(dev, XenbusStateInitialised);
 	return 0;

  error_xenbus:
 	xenbus_transaction_end(xbt, 1);
 	xenbus_dev_fatal(dev, ret, "writing xenstore");
 	return ret;
 }

 static void xenkbd_disconnect_backend(struct xenkbd_info *info)
 {
 	if (info->irq >= 0)
 		unbind_from_irqhandler(info->irq, info);
 	info->irq = -1;
 }

 static void xenkbd_backend_changed(struct xenbus_device *dev,
 				   enum xenbus_state backend_state)
 {
 	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
 	int val;

 	switch (backend_state) {
 	case XenbusStateInitialising:
 	case XenbusStateInitialised:
 	case XenbusStateUnknown:
 	case XenbusStateClosed:
 		break;

 	case XenbusStateInitWait:
 InitWait:
 		xenbus_switch_state(dev, XenbusStateConnected);
 		break;

 	case XenbusStateConnected:
 		/*
 		 * Work around xenbus race condition: If backend goes
 		 * through InitWait to Connected fast enough, we can
 		 * get Connected twice here.
 		 */
 		if (dev->state != XenbusStateConnected)
 			goto InitWait; /* no InitWait seen yet, fudge it */

 		/* Set input abs params to match backend screen res */
 		if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
 				 "width", "%d", &val) > 0)
 			input_set_abs_params(info->ptr, ABS_X, 0, val, 0, 0);

 		if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
 				 "height", "%d", &val) > 0)
 			input_set_abs_params(info->ptr, ABS_Y, 0, val, 0, 0);

 		break;

 	case XenbusStateClosing:
 		xenbus_frontend_closed(dev);
 		break;
 	}
 }

 static const struct xenbus_device_id xenkbd_ids[] = {
 	{ "vkbd" },
 	{ "" }
 };

 static struct xenbus_driver xenkbd_driver = {
 	.name = "vkbd",
 	.owner = THIS_MODULE,
 	.ids = xenkbd_ids,
 	.probe = xenkbd_probe,
 	.remove = xenkbd_remove,
 	.resume = xenkbd_resume,
 	.otherend_changed = xenkbd_backend_changed,
 };

 static int __init xenkbd_init(void)
 {
 	if (!xen_domain())
 		return -ENODEV;

 	/* Nothing to do if running in dom0. */
 	if (xen_initial_domain())
 		return -ENODEV;

 	return xenbus_register_frontend(&xenkbd_driver);
 }

 static void __exit xenkbd_cleanup(void)
 {
 	xenbus_unregister_driver(&xenkbd_driver);
 }

 module_init(xenkbd_init);
 module_exit(xenkbd_cleanup);

 MODULE_DESCRIPTION("Xen virtual keyboard/pointer device frontend");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("xen:vkbd");
	/*
	* Xen para-virtual input device
	*
	* Copyright (C) 2005 Anthony Liguori <aliguori@us.ibm.com>
	* Copyright (C) 2006-2008 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
	*
	* Based on linux/drivers/input/mouse/sermouse.c
	*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file COPYING in the main directory of this archive for
	* more details.
	*/

	/*
	* TODO:
	*
	* Switch to grant tables together with xen-fbfront.c.
	*/

	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/module.h>
	#include <linux/input.h>
	#include <linux/slab.h>

	#include <asm/xen/hypervisor.h>

	#include <xen/xen.h>
	#include <xen/events.h>
	#include <xen/page.h>
	#include <xen/interface/io/fbif.h>
	#include <xen/interface/io/kbdif.h>
	#include <xen/xenbus.h>

	struct xenkbd_info {
	struct input_dev *kbd;
	struct input_dev *ptr;
	struct xenkbd_page *page;
	int irq;
	struct xenbus_device *xbdev;
	char phys[32];
	};

	static int xenkbd_remove(struct xenbus_device *);
	static int xenkbd_connect_backend(struct xenbus_device , struct xenkbd_info );
	static void xenkbd_disconnect_backend(struct xenkbd_info *);

	/*
	* Note: if you need to send out events, see xenfb_do_update() for how
	* to do that.
	*/

	static irqreturn_t input_handler(int rq, void *dev_id)
	{
	struct xenkbd_info *info = dev_id;
	struct xenkbd_page *page = info->page;
	__u32 cons, prod;

	prod = page->in_prod;
	if (prod == page->in_cons)
	return IRQ_HANDLED;
	rmb(); /* ensure we see ring contents up to prod */
	for (cons = page->in_cons; cons != prod; cons++) {
	union xenkbd_in_event *event;
	struct input_dev *dev;
	event = &XENKBD_IN_RING_REF(page, cons);

	dev = info->ptr;
	switch (event->type) {
	case XENKBD_TYPE_MOTION:
	input_report_rel(dev, REL_X, event->motion.rel_x);
	input_report_rel(dev, REL_Y, event->motion.rel_y);
	if (event->motion.rel_z)
	input_report_rel(dev, REL_WHEEL,
	-event->motion.rel_z);
	break;
	case XENKBD_TYPE_KEY:
	dev = NULL;
	if (test_bit(event->key.keycode, info->kbd->keybit))
	dev = info->kbd;
	if (test_bit(event->key.keycode, info->ptr->keybit))
	dev = info->ptr;
	if (dev)
	input_report_key(dev, event->key.keycode,
	event->key.pressed);
	else
	printk(KERN_WARNING
	"xenkbd: unhandled keycode 0x%x\n",
	event->key.keycode);
	break;
	case XENKBD_TYPE_POS:
	input_report_abs(dev, ABS_X, event->pos.abs_x);
	input_report_abs(dev, ABS_Y, event->pos.abs_y);
	if (event->pos.rel_z)
	input_report_rel(dev, REL_WHEEL,
	-event->pos.rel_z);
	break;
	}
	if (dev)
	input_sync(dev);
	}
	mb(); /* ensure we got ring contents */
	page->in_cons = cons;
	notify_remote_via_irq(info->irq);

	return IRQ_HANDLED;
	}

	static int __devinit xenkbd_probe(struct xenbus_device *dev,
	const struct xenbus_device_id *id)
	{
	int ret, i, abs;
	struct xenkbd_info *info;
	struct input_dev kbd, ptr;

	info = kzalloc(sizeof(*info), GFP_KERNEL);
	if (!info) {
	xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
	return -ENOMEM;
	}
	dev_set_drvdata(&dev->dev, info);
	info->xbdev = dev;
	info->irq = -1;
	snprintf(info->phys, sizeof(info->phys), "xenbus/%s", dev->nodename);

	info->page = (void *)__get_free_page(GFP_KERNEL \| __GFP_ZERO);
	if (!info->page)
	goto error_nomem;

	if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-abs-pointer", "%d", &abs) < 0)
	abs = 0;
	if (abs)
	xenbus_printf(XBT_NIL, dev->nodename, "request-abs-pointer", "1");

	/* keyboard */
	kbd = input_allocate_device();
	if (!kbd)
	goto error_nomem;
	kbd->name = "Xen Virtual Keyboard";
	kbd->phys = info->phys;
	kbd->id.bustype = BUS_PCI;
	kbd->id.vendor = 0x5853;
	kbd->id.product = 0xffff;

	__set_bit(EV_KEY, kbd->evbit);
	for (i = KEY_ESC; i < KEY_UNKNOWN; i++)
	__set_bit(i, kbd->keybit);
	for (i = KEY_OK; i < KEY_MAX; i++)
	__set_bit(i, kbd->keybit);

	ret = input_register_device(kbd);
	if (ret) {
	input_free_device(kbd);
	xenbus_dev_fatal(dev, ret, "input_register_device(kbd)");
	goto error;
	}
	info->kbd = kbd;

	/* pointing device */
	ptr = input_allocate_device();
	if (!ptr)
	goto error_nomem;
	ptr->name = "Xen Virtual Pointer";
	ptr->phys = info->phys;
	ptr->id.bustype = BUS_PCI;
	ptr->id.vendor = 0x5853;
	ptr->id.product = 0xfffe;

	if (abs) {
	__set_bit(EV_ABS, ptr->evbit);
	input_set_abs_params(ptr, ABS_X, 0, XENFB_WIDTH, 0, 0);
	input_set_abs_params(ptr, ABS_Y, 0, XENFB_HEIGHT, 0, 0);
	} else {
	input_set_capability(ptr, EV_REL, REL_X);
	input_set_capability(ptr, EV_REL, REL_Y);
	}
	input_set_capability(ptr, EV_REL, REL_WHEEL);

	__set_bit(EV_KEY, ptr->evbit);
	for (i = BTN_LEFT; i <= BTN_TASK; i++)
	__set_bit(i, ptr->keybit);

	ret = input_register_device(ptr);
	if (ret) {
	input_free_device(ptr);
	xenbus_dev_fatal(dev, ret, "input_register_device(ptr)");
	goto error;
	}
	info->ptr = ptr;

	ret = xenkbd_connect_backend(dev, info);
	if (ret < 0)
	goto error;

	return 0;

	error_nomem:
	ret = -ENOMEM;
	xenbus_dev_fatal(dev, ret, "allocating device memory");
	error:
	xenkbd_remove(dev);
	return ret;
	}

	static int xenkbd_resume(struct xenbus_device *dev)
	{
	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);

	xenkbd_disconnect_backend(info);
	memset(info->page, 0, PAGE_SIZE);
	return xenkbd_connect_backend(dev, info);
	}

	static int xenkbd_remove(struct xenbus_device *dev)
	{
	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);

	xenkbd_disconnect_backend(info);
	if (info->kbd)
	input_unregister_device(info->kbd);
	if (info->ptr)
	input_unregister_device(info->ptr);
	free_page((unsigned long)info->page);
	kfree(info);
	return 0;
	}

	static int xenkbd_connect_backend(struct xenbus_device *dev,
	struct xenkbd_info *info)
	{
	int ret, evtchn;
	struct xenbus_transaction xbt;

	ret = xenbus_alloc_evtchn(dev, &evtchn);
	if (ret)
	return ret;
	ret = bind_evtchn_to_irqhandler(evtchn, input_handler,
	0, dev->devicetype, info);
	if (ret < 0) {
	xenbus_free_evtchn(dev, evtchn);
	xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
	return ret;
	}
	info->irq = ret;

	again:
	ret = xenbus_transaction_start(&xbt);
	if (ret) {
	xenbus_dev_fatal(dev, ret, "starting transaction");
	return ret;
	}
	ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
	virt_to_mfn(info->page));
	if (ret)
	goto error_xenbus;
	ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
	evtchn);
	if (ret)
	goto error_xenbus;
	ret = xenbus_transaction_end(xbt, 0);
	if (ret) {
	if (ret == -EAGAIN)
	goto again;
	xenbus_dev_fatal(dev, ret, "completing transaction");
	return ret;
	}

	xenbus_switch_state(dev, XenbusStateInitialised);
	return 0;

	error_xenbus:
	xenbus_transaction_end(xbt, 1);
	xenbus_dev_fatal(dev, ret, "writing xenstore");
	return ret;
	}

	static void xenkbd_disconnect_backend(struct xenkbd_info *info)
	{
	if (info->irq >= 0)
	unbind_from_irqhandler(info->irq, info);
	info->irq = -1;
	}

	static void xenkbd_backend_changed(struct xenbus_device *dev,
	enum xenbus_state backend_state)
	{
	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
	int val;

	switch (backend_state) {
	case XenbusStateInitialising:
	case XenbusStateInitialised:
	case XenbusStateUnknown:
	case XenbusStateClosed:
	break;

	case XenbusStateInitWait:
	InitWait:
	xenbus_switch_state(dev, XenbusStateConnected);
	break;

	case XenbusStateConnected:
	/*
	* Work around xenbus race condition: If backend goes
	* through InitWait to Connected fast enough, we can
	* get Connected twice here.
	*/
	if (dev->state != XenbusStateConnected)
	goto InitWait; /* no InitWait seen yet, fudge it */

	/* Set input abs params to match backend screen res */
	if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
	"width", "%d", &val) > 0)
	input_set_abs_params(info->ptr, ABS_X, 0, val, 0, 0);

	if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
	"height", "%d", &val) > 0)
	input_set_abs_params(info->ptr, ABS_Y, 0, val, 0, 0);

	break;

	case XenbusStateClosing:
	xenbus_frontend_closed(dev);
	break;
	}
	}

	static const struct xenbus_device_id xenkbd_ids[] = {
	{ "vkbd" },
	{ "" }
	};

	static struct xenbus_driver xenkbd_driver = {
	.name = "vkbd",
	.owner = THIS_MODULE,
	.ids = xenkbd_ids,
	.probe = xenkbd_probe,
	.remove = xenkbd_remove,
	.resume = xenkbd_resume,
	.otherend_changed = xenkbd_backend_changed,
	};

	static int __init xenkbd_init(void)
	{
	if (!xen_domain())
	return -ENODEV;

	/* Nothing to do if running in dom0. */
	if (xen_initial_domain())
	return -ENODEV;

	return xenbus_register_frontend(&xenkbd_driver);
	}

	static void __exit xenkbd_cleanup(void)
	{
	xenbus_unregister_driver(&xenkbd_driver);
	}

	module_init(xenkbd_init);
	module_exit(xenkbd_cleanup);

	MODULE_DESCRIPTION("Xen virtual keyboard/pointer device frontend");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("xen:vkbd");