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)

1 files changed, 91 insertions, 0 deletions

diff --git a/drivers/hid/hid-vrc2.c b/drivers/hid/hid-vrc2.c
new file mode 100644
index 000000000..7dc41e92f
--- /dev/null
+++ b/drivers/hid/hid-vrc2.c
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * HID driver for VRC-2 2-axis Car controller
+ *
+ * Copyright (C) 2022 Marcus Folkesson <marcus.folkesson@gmail.com>
+ */
+
+#include <linux/device.h>
+#include <linux/hid.h>
+#include <linux/module.h>
+
+/*
+ * VID/PID are probably "borrowed", so keep them locally and
+ * do not populate hid-ids.h with those.
+ */
+#define USB_VENDOR_ID_VRC2	(0x07c0)
+#define USB_DEVICE_ID_VRC2	(0x1125)
+
+static const __u8 vrc2_rdesc_fixed[] = {
+	0x05, 0x01,        // Usage Page (Generic Desktop Ctrls)
+	0x09, 0x04,        // Usage (Joystick)
+	0xA1, 0x01,        // Collection (Application)
+	0x09, 0x01,        //   Usage (Pointer)
+	0xA1, 0x00,        //   Collection (Physical)
+	0x09, 0x30,        //     Usage (X)
+	0x09, 0x31,        //     Usage (Y)
+	0x15, 0x00,        //     Logical Minimum (0)
+	0x26, 0xFF, 0x07,  //     Logical Maximum (2047)
+	0x35, 0x00,        //     Physical Minimum (0)
+	0x46, 0xFF, 0x00,  //     Physical Maximum (255)
+	0x75, 0x10,        //     Report Size (16)
+	0x95, 0x02,        //     Report Count (2)
+	0x81, 0x02,        //     Input (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position)
+	0xC0,              //   End Collection
+	0x75, 0x08,        //   Report Size (8)
+	0x95, 0x03,        //   Report Count (3)
+	0x81, 0x03,        //   Input (Cnst,Var,Abs)
+	0xC0,              // End Collection
+};
+
+static const __u8 *vrc2_report_fixup(struct hid_device *hdev, __u8 *rdesc,
+				     unsigned int *rsize)
+{
+	hid_info(hdev, "fixing up VRC-2 report descriptor\n");
+	*rsize = sizeof(vrc2_rdesc_fixed);
+	return vrc2_rdesc_fixed;
+}
+
+static int vrc2_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	int ret;
+
+	/*
+	 * The device gives us 2 separate USB endpoints.
+	 * One of those (the one with report descriptor size of 23) is just bogus so ignore it
+	 */
+	if (hdev->dev_rsize == 23)
+		return -ENODEV;
+
+	ret = hid_parse(hdev);
+	if (ret) {
+		hid_err(hdev, "parse failed\n");
+		return ret;
+	}
+
+	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+	if (ret) {
+		hid_err(hdev, "hw start failed\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct hid_device_id vrc2_devices[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_VRC2, USB_DEVICE_ID_VRC2) },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(hid, vrc2_devices);
+
+static struct hid_driver vrc2_driver = {
+	.name = "vrc2",
+	.id_table = vrc2_devices,
+	.report_fixup = vrc2_report_fixup,
+	.probe = vrc2_probe,
+};
+module_hid_driver(vrc2_driver);
+
+MODULE_AUTHOR("Marcus Folkesson <marcus.folkesson@gmail.com>");
+MODULE_DESCRIPTION("HID driver for VRC-2 2-axis Car controller");
+MODULE_LICENSE("GPL");