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authorAdrian Betschart <adrian.betschart@cinemaone.ch>2026-09-11 17:13:14 +0200
committerAlex Deucher <alexander.deucher@amd.com>2026-10-01 17:18:05 -0400
commit106b4a2a78b2a2f14885604891957b84bba502db (patch)
tree5d40eef2428fb1a4791ab46a4b19091a5910eac2 /drivers/input/misc/xen-kbdfront.c
downloadlinux-stable-106b4a2a78b2a2f14885604891957b84bba502db.tar.gz
linux-stable-106b4a2a78b2a2f14885604891957b84bba502db.zip
drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validationgrafted
amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and uses the first encoding that validates. YCbCr 4:4:4 is listed before RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the "color format" property is left at AUTO, even though RGB fits the same link. That contradicts the documented AUTO behaviour for HDMI in enum drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when the bandwidth is not available or the mode is 4:2:0-only), which the amdgpu implementation of the property also describes. It also leaves the "Broadcast RGB" property without effect on such sinks, since the quantization range it selects only applies to RGB output. Try RGB first. The mask still holds every encoding the sink supports, so a mode that cannot carry RGB falls back exactly as before. For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI sink that advertised it. Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation") Suggested-by: Adolfo Rodrigues <adolfotregosa@gmail.com> Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart <adrian.betschart@cinemaone.ch> Reviewed-by: Fangzhi Zuo <jerry.zuo@amd.com> Tested-by: Adolfo Rodrigues <adolfotregosa@gmail.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7)
Diffstat (limited to 'drivers/input/misc/xen-kbdfront.c')
-rw-r--r--drivers/input/misc/xen-kbdfront.c572
1 files changed, 572 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..6471d836f
--- /dev/null
+++ b/drivers/input/misc/xen-kbdfront.c
@@ -0,0 +1,572 @@
+/*
+ * 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/input/mt.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 input_dev *mtouch;
+ struct xenkbd_page *page;
+ int gref;
+ int irq;
+ struct xenbus_device *xbdev;
+ char phys[32];
+ /* current MT slot/contact ID we are injecting events in */
+ int mtouch_cur_contact_id;
+};
+
+enum { KPARAM_X, KPARAM_Y, KPARAM_CNT };
+static int ptr_size[KPARAM_CNT] = { XENFB_WIDTH, XENFB_HEIGHT };
+module_param_array(ptr_size, int, NULL, 0444);
+MODULE_PARM_DESC(ptr_size,
+ "Pointing device width, height in pixels (default 800,600)");
+
+static void 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 void xenkbd_handle_motion_event(struct xenkbd_info *info,
+ struct xenkbd_motion *motion)
+{
+ if (unlikely(!info->ptr))
+ return;
+
+ input_report_rel(info->ptr, REL_X, motion->rel_x);
+ input_report_rel(info->ptr, REL_Y, motion->rel_y);
+ if (motion->rel_z)
+ input_report_rel(info->ptr, REL_WHEEL, -motion->rel_z);
+ input_sync(info->ptr);
+}
+
+static void xenkbd_handle_position_event(struct xenkbd_info *info,
+ struct xenkbd_position *pos)
+{
+ if (unlikely(!info->ptr))
+ return;
+
+ input_report_abs(info->ptr, ABS_X, pos->abs_x);
+ input_report_abs(info->ptr, ABS_Y, pos->abs_y);
+ if (pos->rel_z)
+ input_report_rel(info->ptr, REL_WHEEL, -pos->rel_z);
+ input_sync(info->ptr);
+}
+
+static void xenkbd_handle_key_event(struct xenkbd_info *info,
+ struct xenkbd_key *key)
+{
+ struct input_dev *dev;
+ int value = key->pressed;
+
+ if (test_bit(key->keycode, info->ptr->keybit)) {
+ dev = info->ptr;
+ } else if (test_bit(key->keycode, info->kbd->keybit)) {
+ dev = info->kbd;
+ if (key->pressed && test_bit(key->keycode, info->kbd->key))
+ value = 2; /* Mark as autorepeat */
+ } else {
+ pr_warn("unhandled keycode 0x%x\n", key->keycode);
+ return;
+ }
+
+ if (unlikely(!dev))
+ return;
+
+ input_event(dev, EV_KEY, key->keycode, value);
+ input_sync(dev);
+}
+
+static void xenkbd_handle_mt_event(struct xenkbd_info *info,
+ struct xenkbd_mtouch *mtouch)
+{
+ if (unlikely(!info->mtouch))
+ return;
+
+ if (mtouch->contact_id != info->mtouch_cur_contact_id) {
+ info->mtouch_cur_contact_id = mtouch->contact_id;
+ input_mt_slot(info->mtouch, mtouch->contact_id);
+ }
+
+ switch (mtouch->event_type) {
+ case XENKBD_MT_EV_DOWN:
+ input_mt_report_slot_state(info->mtouch, MT_TOOL_FINGER, true);
+ fallthrough;
+
+ case XENKBD_MT_EV_MOTION:
+ input_report_abs(info->mtouch, ABS_MT_POSITION_X,
+ mtouch->u.pos.abs_x);
+ input_report_abs(info->mtouch, ABS_MT_POSITION_Y,
+ mtouch->u.pos.abs_y);
+ break;
+
+ case XENKBD_MT_EV_SHAPE:
+ input_report_abs(info->mtouch, ABS_MT_TOUCH_MAJOR,
+ mtouch->u.shape.major);
+ input_report_abs(info->mtouch, ABS_MT_TOUCH_MINOR,
+ mtouch->u.shape.minor);
+ break;
+
+ case XENKBD_MT_EV_ORIENT:
+ input_report_abs(info->mtouch, ABS_MT_ORIENTATION,
+ mtouch->u.orientation);
+ break;
+
+ case XENKBD_MT_EV_UP:
+ input_mt_report_slot_inactive(info->mtouch);
+ break;
+
+ case XENKBD_MT_EV_SYN:
+ input_mt_sync_frame(info->mtouch);
+ input_sync(info->mtouch);
+ break;
+ }
+}
+
+static void xenkbd_handle_event(struct xenkbd_info *info,
+ union xenkbd_in_event *event)
+{
+ switch (event->type) {
+ case XENKBD_TYPE_MOTION:
+ xenkbd_handle_motion_event(info, &event->motion);
+ break;
+
+ case XENKBD_TYPE_KEY:
+ xenkbd_handle_key_event(info, &event->key);
+ break;
+
+ case XENKBD_TYPE_POS:
+ xenkbd_handle_position_event(info, &event->pos);
+ break;
+
+ case XENKBD_TYPE_MTOUCH:
+ xenkbd_handle_mt_event(info, &event->mtouch);
+ break;
+ }
+}
+
+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++)
+ xenkbd_handle_event(info, &XENKBD_IN_RING_REF(page, cons));
+ 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;
+ bool with_mtouch, with_kbd, with_ptr;
+ struct xenkbd_info *info;
+ struct input_dev *kbd, *ptr, *mtouch;
+
+ info = kzalloc_obj(*info);
+ 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;
+
+ /*
+ * The below are reverse logic, e.g. if the feature is set, then
+ * do not expose the corresponding virtual device.
+ */
+ with_kbd = !xenbus_read_unsigned(dev->otherend,
+ XENKBD_FIELD_FEAT_DSBL_KEYBRD, 0);
+
+ with_ptr = !xenbus_read_unsigned(dev->otherend,
+ XENKBD_FIELD_FEAT_DSBL_POINTER, 0);
+
+ /* Direct logic: if set, then create multi-touch device. */
+ with_mtouch = xenbus_read_unsigned(dev->otherend,
+ XENKBD_FIELD_FEAT_MTOUCH, 0);
+ if (with_mtouch) {
+ ret = xenbus_write(XBT_NIL, dev->nodename,
+ XENKBD_FIELD_REQ_MTOUCH, "1");
+ if (ret) {
+ pr_warn("xenkbd: can't request multi-touch");
+ with_mtouch = 0;
+ }
+ }
+
+ /* keyboard */
+ if (with_kbd) {
+ 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 */
+ if (with_ptr) {
+ unsigned int abs;
+
+ /* Set input abs params to match backend screen res */
+ abs = xenbus_read_unsigned(dev->otherend,
+ XENKBD_FIELD_FEAT_ABS_POINTER, 0);
+ ptr_size[KPARAM_X] = xenbus_read_unsigned(dev->otherend,
+ XENKBD_FIELD_WIDTH,
+ ptr_size[KPARAM_X]);
+ ptr_size[KPARAM_Y] = xenbus_read_unsigned(dev->otherend,
+ XENKBD_FIELD_HEIGHT,
+ ptr_size[KPARAM_Y]);
+ if (abs) {
+ ret = xenbus_write(XBT_NIL, dev->nodename,
+ XENKBD_FIELD_REQ_ABS_POINTER, "1");
+ if (ret) {
+ pr_warn("xenkbd: can't request abs-pointer\n");
+ abs = 0;
+ }
+ }
+
+ 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,
+ ptr_size[KPARAM_X], 0, 0);
+ input_set_abs_params(ptr, ABS_Y, 0,
+ ptr_size[KPARAM_Y], 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;
+ }
+
+ /* multi-touch device */
+ if (with_mtouch) {
+ int num_cont, width, height;
+
+ mtouch = input_allocate_device();
+ if (!mtouch)
+ goto error_nomem;
+
+ num_cont = xenbus_read_unsigned(info->xbdev->otherend,
+ XENKBD_FIELD_MT_NUM_CONTACTS,
+ 1);
+ width = xenbus_read_unsigned(info->xbdev->otherend,
+ XENKBD_FIELD_MT_WIDTH,
+ XENFB_WIDTH);
+ height = xenbus_read_unsigned(info->xbdev->otherend,
+ XENKBD_FIELD_MT_HEIGHT,
+ XENFB_HEIGHT);
+
+ mtouch->name = "Xen Virtual Multi-touch";
+ mtouch->phys = info->phys;
+ mtouch->id.bustype = BUS_PCI;
+ mtouch->id.vendor = 0x5853;
+ mtouch->id.product = 0xfffd;
+
+ input_set_abs_params(mtouch, ABS_MT_TOUCH_MAJOR,
+ 0, 255, 0, 0);
+ input_set_abs_params(mtouch, ABS_MT_POSITION_X,
+ 0, width, 0, 0);
+ input_set_abs_params(mtouch, ABS_MT_POSITION_Y,
+ 0, height, 0, 0);
+
+ ret = input_mt_init_slots(mtouch, num_cont, INPUT_MT_DIRECT);
+ if (ret) {
+ input_free_device(mtouch);
+ xenbus_dev_fatal(info->xbdev, ret,
+ "input_mt_init_slots");
+ goto error;
+ }
+
+ ret = input_register_device(mtouch);
+ if (ret) {
+ input_free_device(mtouch);
+ xenbus_dev_fatal(info->xbdev, ret,
+ "input_register_device(mtouch)");
+ goto error;
+ }
+ info->mtouch_cur_contact_id = -1;
+ info->mtouch = mtouch;
+ }
+
+ if (!(with_kbd || with_ptr || with_mtouch)) {
+ ret = -ENXIO;
+ goto error;
+ }
+
+ 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 void 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);
+ if (info->mtouch)
+ input_unregister_device(info->mtouch);
+ free_page((unsigned long)info->page);
+ kfree(info);
+}
+
+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_gfn(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, XENKBD_FIELD_RING_REF, "%lu",
+ virt_to_gfn(info->page));
+ if (ret)
+ goto error_xenbus;
+ ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_RING_GREF,
+ "%u", info->gref);
+ if (ret)
+ goto error_xenbus;
+ ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_EVT_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, NULL);
+ 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, NULL);
+ info->gref = -1;
+}
+
+static void xenkbd_backend_changed(struct xenbus_device *dev,
+ enum xenbus_state backend_state)
+{
+ switch (backend_state) {
+ case XenbusStateInitialising:
+ case XenbusStateInitialised:
+ case XenbusStateReconfiguring:
+ case XenbusStateReconfigured:
+ case XenbusStateUnknown:
+ break;
+
+ case XenbusStateInitWait:
+ 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)
+ xenbus_switch_state(dev, XenbusStateConnected);
+ break;
+
+ case XenbusStateClosed:
+ if (dev->state == XenbusStateClosed)
+ break;
+ fallthrough; /* Missed the backend's CLOSING state */
+ case XenbusStateClosing:
+ xenbus_frontend_closed(dev);
+ break;
+ }
+}
+
+static const struct xenbus_device_id xenkbd_ids[] = {
+ { XENKBD_DRIVER_NAME },
+ { "" }
+};
+
+static struct xenbus_driver xenkbd_driver = {
+ .ids = xenkbd_ids,
+ .probe = xenkbd_probe,
+ .remove = xenkbd_remove,
+ .resume = xenkbd_resume,
+ .otherend_changed = xenkbd_backend_changed,
+ .not_essential = true,
+};
+
+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:" XENKBD_DRIVER_NAME);