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/regulator/event.c | 91 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 drivers/regulator/event.c (limited to 'drivers/regulator/event.c') diff --git a/drivers/regulator/event.c b/drivers/regulator/event.c new file mode 100644 index 000000000..ea3bd4954 --- /dev/null +++ b/drivers/regulator/event.c @@ -0,0 +1,91 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Regulator event over netlink + * + * Author: Naresh Solanki + */ + +#include +#include +#include +#include + +#include "regnl.h" + +static atomic_t reg_event_seqnum = ATOMIC_INIT(0); + +static const struct genl_multicast_group reg_event_mcgrps[] = { + { .name = REG_GENL_MCAST_GROUP_NAME, }, +}; + +static struct genl_family reg_event_genl_family __ro_after_init = { + .module = THIS_MODULE, + .name = REG_GENL_FAMILY_NAME, + .version = REG_GENL_VERSION, + .maxattr = REG_GENL_ATTR_MAX, + .mcgrps = reg_event_mcgrps, + .n_mcgrps = ARRAY_SIZE(reg_event_mcgrps), +}; + +int reg_generate_netlink_event(const char *reg_name, u64 event) +{ + struct sk_buff *skb; + struct nlattr *attr; + struct reg_genl_event *edata; + void *msg_header; + int size; + + /* allocate memory */ + size = nla_total_size(sizeof(struct reg_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, atomic_inc_return(®_event_seqnum), + ®_event_genl_family, 0, REG_GENL_CMD_EVENT); + if (!msg_header) { + nlmsg_free(skb); + return -ENOMEM; + } + + /* fill the data */ + attr = nla_reserve(skb, REG_GENL_ATTR_EVENT, sizeof(struct reg_genl_event)); + if (!attr) { + nlmsg_free(skb); + return -EINVAL; + } + + edata = nla_data(attr); + memset(edata, 0, sizeof(struct reg_genl_event)); + + strscpy(edata->reg_name, reg_name, sizeof(edata->reg_name)); + edata->event = event; + + /* send multicast genetlink message */ + genlmsg_end(skb, msg_header); + size = genlmsg_multicast(®_event_genl_family, skb, 0, 0, GFP_ATOMIC); + + return size; +} + +static int __init reg_event_genetlink_init(void) +{ + return genl_register_family(®_event_genl_family); +} + +static int __init reg_event_init(void) +{ + int error; + + /* create genetlink for acpi event */ + error = reg_event_genetlink_init(); + if (error) + pr_warn("Failed to create genetlink family for reg event\n"); + + return 0; +} + +fs_initcall(reg_event_init); -- cgit v1.3.1