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, 150 insertions, 0 deletions

diff --git a/drivers/input/mouse/amimouse.c b/drivers/input/mouse/amimouse.c
new file mode 100644
index 000000000..d203c2a6c
--- /dev/null
+++ b/drivers/input/mouse/amimouse.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  Amiga mouse driver for Linux/m68k
+ *
+ *  Copyright (c) 2000-2002 Vojtech Pavlik
+ *
+ *  Based on the work of:
+ *	Michael Rausch		James Banks
+ *	Matther Dillon		David Giller
+ *	Nathan Laredo		Linus Torvalds
+ *	Johan Myreen		Jes Sorensen
+ *	Russell King
+ */
+
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+
+#include <asm/irq.h>
+#include <asm/setup.h>
+#include <linux/uaccess.h>
+#include <asm/amigahw.h>
+#include <asm/amigaints.h>
+
+MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
+MODULE_DESCRIPTION("Amiga mouse driver");
+MODULE_LICENSE("GPL");
+
+static int amimouse_lastx, amimouse_lasty;
+
+static irqreturn_t amimouse_interrupt(int irq, void *data)
+{
+	struct input_dev *dev = data;
+	unsigned short joy0dat, potgor;
+	int nx, ny, dx, dy;
+
+	joy0dat = amiga_custom.joy0dat;
+
+	nx = joy0dat & 0xff;
+	ny = joy0dat >> 8;
+
+	dx = nx - amimouse_lastx;
+	dy = ny - amimouse_lasty;
+
+	if (dx < -127) dx = (256 + nx) - amimouse_lastx;
+	if (dx >  127) dx = (nx - 256) - amimouse_lastx;
+	if (dy < -127) dy = (256 + ny) - amimouse_lasty;
+	if (dy >  127) dy = (ny - 256) - amimouse_lasty;
+
+	amimouse_lastx = nx;
+	amimouse_lasty = ny;
+
+	potgor = amiga_custom.potgor;
+
+	input_report_rel(dev, REL_X, dx);
+	input_report_rel(dev, REL_Y, dy);
+
+	input_report_key(dev, BTN_LEFT,   ciaa.pra & 0x40);
+	input_report_key(dev, BTN_MIDDLE, potgor & 0x0100);
+	input_report_key(dev, BTN_RIGHT,  potgor & 0x0400);
+
+	input_sync(dev);
+
+	return IRQ_HANDLED;
+}
+
+static int amimouse_open(struct input_dev *dev)
+{
+	unsigned short joy0dat;
+	int error;
+
+	joy0dat = amiga_custom.joy0dat;
+
+	amimouse_lastx = joy0dat & 0xff;
+	amimouse_lasty = joy0dat >> 8;
+
+	error = request_irq(IRQ_AMIGA_VERTB, amimouse_interrupt, 0, "amimouse",
+			    dev);
+	if (error)
+		dev_err(&dev->dev, "Can't allocate irq %d\n", IRQ_AMIGA_VERTB);
+
+	return error;
+}
+
+static void amimouse_close(struct input_dev *dev)
+{
+	free_irq(IRQ_AMIGA_VERTB, dev);
+}
+
+static int __init amimouse_probe(struct platform_device *pdev)
+{
+	int err;
+	struct input_dev *dev;
+
+	dev = input_allocate_device();
+	if (!dev)
+		return -ENOMEM;
+
+	dev->name = pdev->name;
+	dev->phys = "amimouse/input0";
+	dev->id.bustype = BUS_AMIGA;
+	dev->id.vendor = 0x0001;
+	dev->id.product = 0x0002;
+	dev->id.version = 0x0100;
+
+	dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
+	dev->relbit[0] = BIT_MASK(REL_X) | BIT_MASK(REL_Y);
+	dev->keybit[BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) |
+		BIT_MASK(BTN_MIDDLE) | BIT_MASK(BTN_RIGHT);
+	dev->open = amimouse_open;
+	dev->close = amimouse_close;
+	dev->dev.parent = &pdev->dev;
+
+	err = input_register_device(dev);
+	if (err) {
+		input_free_device(dev);
+		return err;
+	}
+
+	platform_set_drvdata(pdev, dev);
+
+	return 0;
+}
+
+static void __exit amimouse_remove(struct platform_device *pdev)
+{
+	struct input_dev *dev = platform_get_drvdata(pdev);
+
+	input_unregister_device(dev);
+}
+
+/*
+ * amimouse_remove() lives in .exit.text. For drivers registered via
+ * module_platform_driver_probe() this is ok because they cannot get unbound at
+ * runtime. So mark the driver struct with __refdata to prevent modpost
+ * triggering a section mismatch warning.
+ */
+static struct platform_driver amimouse_driver __refdata = {
+	.remove = __exit_p(amimouse_remove),
+	.driver   = {
+		.name	= "amiga-mouse",
+	},
+};
+
+module_platform_driver_probe(amimouse_driver, amimouse_probe);
+
+MODULE_ALIAS("platform:amiga-mouse");