From 106b4a2a78b2a2f14885604891957b84bba502db Mon Sep 17 00:00:00 2001 From: Adrian Betschart Date: Fri, 11 Sep 2026 17:13:14 +0200 Subject: drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validation 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 Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart Reviewed-by: Fangzhi Zuo Tested-by: Adolfo Rodrigues Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7) --- drivers/acpi/event.c | 184 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 184 insertions(+) create mode 100644 drivers/acpi/event.c (limited to 'drivers/acpi/event.c') diff --git a/drivers/acpi/event.c b/drivers/acpi/event.c new file mode 100644 index 000000000..4d840d2e7 --- /dev/null +++ b/drivers/acpi/event.c @@ -0,0 +1,184 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * event.c - exporting ACPI events via procfs + * + * Copyright (C) 2001, 2002 Andy Grover + * Copyright (C) 2001, 2002 Paul Diefenbaugh + * + */ + +#define pr_fmt(fmt) "ACPI: " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "internal.h" + +/* ACPI notifier chain */ +static BLOCKING_NOTIFIER_HEAD(acpi_chain_head); + +int acpi_notifier_call_chain(const char *device_class, + const char *bus_id, u32 type, u32 data) +{ + struct acpi_bus_event event; + + strscpy(event.device_class, device_class); + strscpy(event.bus_id, bus_id); + event.type = type; + event.data = data; + return (blocking_notifier_call_chain(&acpi_chain_head, 0, (void *)&event) + == NOTIFY_BAD) ? -EINVAL : 0; +} +EXPORT_SYMBOL(acpi_notifier_call_chain); + +int register_acpi_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_register(&acpi_chain_head, nb); +} +EXPORT_SYMBOL(register_acpi_notifier); + +int unregister_acpi_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_unregister(&acpi_chain_head, nb); +} +EXPORT_SYMBOL(unregister_acpi_notifier); + +#ifdef CONFIG_NET +static unsigned int acpi_event_seqnum; +struct acpi_genl_event { + acpi_device_class device_class; + char bus_id[15]; + u32 type; + u32 data; +}; + +/* attributes of acpi_genl_family */ +enum { + ACPI_GENL_ATTR_UNSPEC, + ACPI_GENL_ATTR_EVENT, /* ACPI event info needed by user space */ + __ACPI_GENL_ATTR_MAX, +}; +#define ACPI_GENL_ATTR_MAX (__ACPI_GENL_ATTR_MAX - 1) + +/* commands supported by the acpi_genl_family */ +enum { + ACPI_GENL_CMD_UNSPEC, + ACPI_GENL_CMD_EVENT, /* kernel->user notifications for ACPI events */ + __ACPI_GENL_CMD_MAX, +}; +#define ACPI_GENL_CMD_MAX (__ACPI_GENL_CMD_MAX - 1) + +#define ACPI_GENL_FAMILY_NAME "acpi_event" +#define ACPI_GENL_VERSION 0x01 +#define ACPI_GENL_MCAST_GROUP_NAME "acpi_mc_group" + +static const struct genl_multicast_group acpi_event_mcgrps[] = { + { .name = ACPI_GENL_MCAST_GROUP_NAME, }, +}; + +static struct genl_family acpi_event_genl_family __ro_after_init = { + .module = THIS_MODULE, + .name = ACPI_GENL_FAMILY_NAME, + .version = ACPI_GENL_VERSION, + .maxattr = ACPI_GENL_ATTR_MAX, + .mcgrps = acpi_event_mcgrps, + .n_mcgrps = ARRAY_SIZE(acpi_event_mcgrps), +}; + +int acpi_bus_generate_netlink_event(const char *device_class, + const char *bus_id, + u8 type, int data) +{ + struct sk_buff *skb; + struct nlattr *attr; + struct acpi_genl_event *event; + void *msg_header; + int size; + + /* allocate memory */ + size = nla_total_size(sizeof(struct acpi_genl_event)) + + nla_total_size(0); + + skb = genlmsg_new(size, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + /* add the genetlink message header */ + msg_header = genlmsg_put(skb, 0, acpi_event_seqnum++, + &acpi_event_genl_family, 0, + ACPI_GENL_CMD_EVENT); + if (!msg_header) { + nlmsg_free(skb); + return -ENOMEM; + } + + /* fill the data */ + attr = + nla_reserve(skb, ACPI_GENL_ATTR_EVENT, + sizeof(struct acpi_genl_event)); + if (!attr) { + nlmsg_free(skb); + return -EINVAL; + } + + event = nla_data(attr); + memset(event, 0, sizeof(struct acpi_genl_event)); + + strscpy(event->device_class, device_class, sizeof(event->device_class)); + strscpy(event->bus_id, bus_id, sizeof(event->bus_id)); + event->type = type; + event->data = data; + + /* send multicast genetlink message */ + genlmsg_end(skb, msg_header); + + genlmsg_multicast(&acpi_event_genl_family, skb, 0, 0, GFP_ATOMIC); + return 0; +} + +EXPORT_SYMBOL(acpi_bus_generate_netlink_event); + +static int __init acpi_event_genetlink_init(void) +{ + return genl_register_family(&acpi_event_genl_family); +} + +#else +int acpi_bus_generate_netlink_event(const char *device_class, + const char *bus_id, + u8 type, int data) +{ + return 0; +} + +EXPORT_SYMBOL(acpi_bus_generate_netlink_event); + +static int acpi_event_genetlink_init(void) +{ + return -ENODEV; +} +#endif + +static int __init acpi_event_init(void) +{ + int error; + + if (acpi_disabled) + return 0; + + /* create genetlink for acpi event */ + error = acpi_event_genetlink_init(); + if (error) + pr_warn("Failed to create genetlink family for ACPI event\n"); + + return 0; +} + +fs_initcall(acpi_event_init); -- cgit v1.3.1