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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/input/misc/xen-kbdfront.c
Initial import
Diffstat (limited to 'drivers/input/misc/xen-kbdfront.c')
-rw-r--r--drivers/input/misc/xen-kbdfront.c401
1 files changed, 401 insertions, 0 deletions
diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c
new file mode 100644
index 000000000..95599e478
--- /dev/null
+++ b/drivers/input/misc/xen-kbdfront.c
@@ -0,0 +1,401 @@
+/*
+ * 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#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/grant_table.h>
+#include <xen/interface/grant_table.h>
+#include <xen/interface/io/fbif.h>
+#include <xen/interface/io/kbdif.h>
+#include <xen/xenbus.h>
+#include <xen/platform_pci.h>
+
+struct xenkbd_info {
+ struct input_dev *kbd;
+ struct input_dev *ptr;
+ struct xenkbd_page *page;
+ int gref;
+ 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
+ pr_warning("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 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;
+ info->gref = -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 = gnttab_grant_foreign_access(dev->otherend_id,
+ virt_to_mfn(info->page), 0);
+ if (ret < 0)
+ return ret;
+ info->gref = ret;
+
+ ret = xenbus_alloc_evtchn(dev, &evtchn);
+ if (ret)
+ goto error_grant;
+ ret = bind_evtchn_to_irqhandler(evtchn, input_handler,
+ 0, dev->devicetype, info);
+ if (ret < 0) {
+ xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
+ goto error_evtchan;
+ }
+ info->irq = ret;
+
+ again:
+ ret = xenbus_transaction_start(&xbt);
+ if (ret) {
+ xenbus_dev_fatal(dev, ret, "starting transaction");
+ goto error_irqh;
+ }
+ 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, "page-gref", "%u", info->gref);
+ 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");
+ goto error_irqh;
+ }
+
+ xenbus_switch_state(dev, XenbusStateInitialised);
+ return 0;
+
+ error_xenbus:
+ xenbus_transaction_end(xbt, 1);
+ xenbus_dev_fatal(dev, ret, "writing xenstore");
+ error_irqh:
+ unbind_from_irqhandler(info->irq, info);
+ info->irq = -1;
+ error_evtchan:
+ xenbus_free_evtchn(dev, evtchn);
+ error_grant:
+ gnttab_end_foreign_access(info->gref, 0, 0UL);
+ info->gref = -1;
+ return ret;
+}
+
+static void xenkbd_disconnect_backend(struct xenkbd_info *info)
+{
+ if (info->irq >= 0)
+ unbind_from_irqhandler(info->irq, info);
+ info->irq = -1;
+ if (info->gref >= 0)
+ gnttab_end_foreign_access(info->gref, 0, 0UL);
+ info->gref = -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 ret, val;
+
+ switch (backend_state) {
+ case XenbusStateInitialising:
+ case XenbusStateInitialised:
+ case XenbusStateReconfiguring:
+ case XenbusStateReconfigured:
+ case XenbusStateUnknown:
+ break;
+
+ case XenbusStateInitWait:
+InitWait:
+ ret = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
+ "feature-abs-pointer", "%d", &val);
+ if (ret < 0)
+ val = 0;
+ if (val) {
+ ret = xenbus_printf(XBT_NIL, info->xbdev->nodename,
+ "request-abs-pointer", "1");
+ if (ret)
+ pr_warning("xenkbd: can't request abs-pointer");
+ }
+
+ 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 XenbusStateClosed:
+ if (dev->state == XenbusStateClosed)
+ break;
+ /* Missed the backend's CLOSING state -- fallthrough */
+ case XenbusStateClosing:
+ xenbus_frontend_closed(dev);
+ break;
+ }
+}
+
+static const struct xenbus_device_id xenkbd_ids[] = {
+ { "vkbd" },
+ { "" }
+};
+
+static struct xenbus_driver xenkbd_driver = {
+ .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;
+
+ if (!xen_has_pv_devices())
+ 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");