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/usb/misc/ehset.c | 190 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 190 insertions(+) create mode 100644 drivers/usb/misc/ehset.c (limited to 'drivers/usb/misc/ehset.c') diff --git a/drivers/usb/misc/ehset.c b/drivers/usb/misc/ehset.c new file mode 100644 index 000000000..36b6e9fa7 --- /dev/null +++ b/drivers/usb/misc/ehset.c @@ -0,0 +1,190 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2010-2013, The Linux Foundation. All rights reserved. + */ + +#include +#include +#include +#include +#include +#include + +#define TEST_SE0_NAK_PID 0x0101 +#define TEST_J_PID 0x0102 +#define TEST_K_PID 0x0103 +#define TEST_PACKET_PID 0x0104 +#define TEST_HS_HOST_PORT_SUSPEND_RESUME 0x0106 +#define TEST_SINGLE_STEP_GET_DEV_DESC 0x0107 +#define TEST_SINGLE_STEP_SET_FEATURE 0x0108 + +extern const struct usb_device_id *usb_device_match_id(struct usb_device *udev, + const struct usb_device_id *id); + +/* + * A list of USB hubs which requires to disable the power + * to the port before starting the testing procedures. + */ +static const struct usb_device_id ehset_hub_list[] = { + { USB_DEVICE(0x0424, 0x4502) }, + { USB_DEVICE(0x0424, 0x4913) }, + { USB_DEVICE(0x0451, 0x8027) }, + { } +}; + +static int ehset_prepare_port_for_testing(struct usb_device *hub_udev, u16 portnum) +{ + int ret = 0; + + /* + * The USB2.0 spec chapter 11.24.2.13 says that the USB port which is + * going under test needs to be put in suspend before sending the + * test command. Most hubs don't enforce this precondition, but there + * are some hubs which needs to disable the power to the port before + * starting the test. + */ + if (usb_device_match_id(hub_udev, ehset_hub_list)) { + ret = usb_control_msg_send(hub_udev, 0, USB_REQ_CLEAR_FEATURE, + USB_RT_PORT, USB_PORT_FEAT_ENABLE, + portnum, NULL, 0, 1000, GFP_KERNEL); + /* + * Wait for the port to be disabled. It's an arbitrary value + * which worked every time. + */ + msleep(100); + } else { + /* + * For the hubs which are compliant with the spec, + * put the port in SUSPEND. + */ + ret = usb_control_msg_send(hub_udev, 0, USB_REQ_SET_FEATURE, + USB_RT_PORT, USB_PORT_FEAT_SUSPEND, + portnum, NULL, 0, 1000, GFP_KERNEL); + } + return ret; +} + +static int ehset_probe(struct usb_interface *intf, + const struct usb_device_id *id) +{ + int ret = -EINVAL; + struct usb_device *dev = interface_to_usbdev(intf); + struct usb_device *hub_udev = dev->parent; + struct usb_device_descriptor buf; + u8 portnum = dev->portnum; + u16 test_pid = le16_to_cpu(dev->descriptor.idProduct); + + switch (test_pid) { + case TEST_SE0_NAK_PID: + ret = ehset_prepare_port_for_testing(hub_udev, portnum); + if (ret < 0) + break; + ret = usb_control_msg_send(hub_udev, 0, USB_REQ_SET_FEATURE, + USB_RT_PORT, USB_PORT_FEAT_TEST, + (USB_TEST_SE0_NAK << 8) | portnum, + NULL, 0, 1000, GFP_KERNEL); + break; + case TEST_J_PID: + ret = ehset_prepare_port_for_testing(hub_udev, portnum); + if (ret < 0) + break; + ret = usb_control_msg_send(hub_udev, 0, USB_REQ_SET_FEATURE, + USB_RT_PORT, USB_PORT_FEAT_TEST, + (USB_TEST_J << 8) | portnum, NULL, 0, + 1000, GFP_KERNEL); + break; + case TEST_K_PID: + ret = ehset_prepare_port_for_testing(hub_udev, portnum); + if (ret < 0) + break; + ret = usb_control_msg_send(hub_udev, 0, USB_REQ_SET_FEATURE, + USB_RT_PORT, USB_PORT_FEAT_TEST, + (USB_TEST_K << 8) | portnum, NULL, 0, + 1000, GFP_KERNEL); + break; + case TEST_PACKET_PID: + ret = ehset_prepare_port_for_testing(hub_udev, portnum); + if (ret < 0) + break; + ret = usb_control_msg_send(hub_udev, 0, USB_REQ_SET_FEATURE, + USB_RT_PORT, USB_PORT_FEAT_TEST, + (USB_TEST_PACKET << 8) | portnum, + NULL, 0, 1000, GFP_KERNEL); + break; + case TEST_HS_HOST_PORT_SUSPEND_RESUME: + /* Test: wait for 15secs -> suspend -> 15secs delay -> resume */ + msleep(15 * 1000); + ret = usb_control_msg_send(hub_udev, 0, USB_REQ_SET_FEATURE, + USB_RT_PORT, USB_PORT_FEAT_SUSPEND, + portnum, NULL, 0, 1000, GFP_KERNEL); + if (ret < 0) + break; + + msleep(15 * 1000); + ret = usb_control_msg_send(hub_udev, 0, USB_REQ_CLEAR_FEATURE, + USB_RT_PORT, USB_PORT_FEAT_SUSPEND, + portnum, NULL, 0, 1000, GFP_KERNEL); + break; + case TEST_SINGLE_STEP_GET_DEV_DESC: + /* Test: wait for 15secs -> GetDescriptor request */ + msleep(15 * 1000); + + ret = usb_control_msg_recv(dev, 0, USB_REQ_GET_DESCRIPTOR, + USB_DIR_IN, USB_DT_DEVICE << 8, 0, + &buf, USB_DT_DEVICE_SIZE, + USB_CTRL_GET_TIMEOUT, GFP_KERNEL); + break; + case TEST_SINGLE_STEP_SET_FEATURE: + /* + * GetDescriptor SETUP request -> 15secs delay -> IN & STATUS + * + * Note, this test is only supported on root hubs since the + * SetPortFeature handling can only be done inside the HCD's + * hub_control callback function. + */ + if (hub_udev != dev->bus->root_hub) { + dev_err(&intf->dev, "SINGLE_STEP_SET_FEATURE test only supported on root hub\n"); + break; + } + + ret = usb_control_msg_send(hub_udev, 0, USB_REQ_SET_FEATURE, + USB_RT_PORT, USB_PORT_FEAT_TEST, + (6 << 8) | portnum, NULL, 0, + 60 * 1000, GFP_KERNEL); + + break; + default: + dev_err(&intf->dev, "%s: unsupported PID: 0x%x\n", + __func__, test_pid); + } + + return ret; +} + +static void ehset_disconnect(struct usb_interface *intf) +{ +} + +static const struct usb_device_id ehset_id_table[] = { + { USB_DEVICE(0x1a0a, TEST_SE0_NAK_PID) }, + { USB_DEVICE(0x1a0a, TEST_J_PID) }, + { USB_DEVICE(0x1a0a, TEST_K_PID) }, + { USB_DEVICE(0x1a0a, TEST_PACKET_PID) }, + { USB_DEVICE(0x1a0a, TEST_HS_HOST_PORT_SUSPEND_RESUME) }, + { USB_DEVICE(0x1a0a, TEST_SINGLE_STEP_GET_DEV_DESC) }, + { USB_DEVICE(0x1a0a, TEST_SINGLE_STEP_SET_FEATURE) }, + { } /* Terminating entry */ +}; +MODULE_DEVICE_TABLE(usb, ehset_id_table); + +static struct usb_driver ehset_driver = { + .name = "usb_ehset_test", + .probe = ehset_probe, + .disconnect = ehset_disconnect, + .id_table = ehset_id_table, +}; + +module_usb_driver(ehset_driver); + +MODULE_DESCRIPTION("USB Driver for EHSET Test Fixture"); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1