diff options
Diffstat (limited to 'drivers/input/misc/xen-kbdfront.c')
| -rw-r--r-- | drivers/input/misc/xen-kbdfront.c | 396 |
1 files changed, 396 insertions, 0 deletions
diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c new file mode 100644 index 00000000000..62bae99424e --- /dev/null +++ b/drivers/input/misc/xen-kbdfront.c @@ -0,0 +1,396 @@ +/* + * 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> + +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 __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; + 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_ref(info->gref, 0); + 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_ref(info->gref, 0); + 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: + case XenbusStateClosed: + 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 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_pv_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"); |