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, 135 insertions, 0 deletions

diff --git a/drivers/leds/trigger/ledtrig-timer.c b/drivers/leds/trigger/ledtrig-timer.c
new file mode 100644
index 000000000..1d213c999
--- /dev/null
+++ b/drivers/leds/trigger/ledtrig-timer.c
@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * LED Kernel Timer Trigger
+ *
+ * Copyright 2005-2006 Openedhand Ltd.
+ *
+ * Author: Richard Purdie <rpurdie@openedhand.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/ctype.h>
+#include <linux/slab.h>
+#include <linux/leds.h>
+
+static ssize_t led_delay_on_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct led_classdev *led_cdev = led_trigger_get_led(dev);
+
+	return sprintf(buf, "%lu\n", led_cdev->blink_delay_on);
+}
+
+static ssize_t led_delay_on_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t size)
+{
+	struct led_classdev *led_cdev = led_trigger_get_led(dev);
+	unsigned long state;
+	ssize_t ret;
+
+	ret = kstrtoul(buf, 10, &state);
+	if (ret)
+		return ret;
+
+	led_blink_set(led_cdev, &state, &led_cdev->blink_delay_off);
+	led_cdev->blink_delay_on = state;
+
+	return size;
+}
+
+static ssize_t led_delay_off_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct led_classdev *led_cdev = led_trigger_get_led(dev);
+
+	return sprintf(buf, "%lu\n", led_cdev->blink_delay_off);
+}
+
+static ssize_t led_delay_off_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t size)
+{
+	struct led_classdev *led_cdev = led_trigger_get_led(dev);
+	unsigned long state;
+	ssize_t ret;
+
+	ret = kstrtoul(buf, 10, &state);
+	if (ret)
+		return ret;
+
+	led_blink_set(led_cdev, &led_cdev->blink_delay_on, &state);
+	led_cdev->blink_delay_off = state;
+
+	return size;
+}
+
+static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
+static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
+
+static struct attribute *timer_trig_attrs[] = {
+	&dev_attr_delay_on.attr,
+	&dev_attr_delay_off.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(timer_trig);
+
+static void pattern_init(struct led_classdev *led_cdev)
+{
+	u32 *pattern;
+	unsigned int size = 0;
+
+	pattern = led_get_default_pattern(led_cdev, &size);
+	if (!pattern)
+		return;
+
+	if (size != 2) {
+		dev_warn(led_cdev->dev,
+			 "Expected 2 but got %u values for delays pattern\n",
+			 size);
+		goto out;
+	}
+
+	led_cdev->blink_delay_on = pattern[0];
+	led_cdev->blink_delay_off = pattern[1];
+	/* led_blink_set() called by caller */
+
+out:
+	kfree(pattern);
+}
+
+static int timer_trig_activate(struct led_classdev *led_cdev)
+{
+	if (led_cdev->flags & LED_INIT_DEFAULT_TRIGGER) {
+		pattern_init(led_cdev);
+		/*
+		 * Mark as initialized even on pattern_init() error because
+		 * any consecutive call to it would produce the same error.
+		 */
+		led_cdev->flags &= ~LED_INIT_DEFAULT_TRIGGER;
+	}
+
+	led_blink_set(led_cdev, &led_cdev->blink_delay_on,
+		      &led_cdev->blink_delay_off);
+
+	return 0;
+}
+
+static void timer_trig_deactivate(struct led_classdev *led_cdev)
+{
+	/* Stop blinking */
+	led_set_brightness(led_cdev, LED_OFF);
+}
+
+static struct led_trigger timer_led_trigger = {
+	.name     = "timer",
+	.activate = timer_trig_activate,
+	.deactivate = timer_trig_deactivate,
+	.groups = timer_trig_groups,
+};
+module_led_trigger(timer_led_trigger);
+
+MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
+MODULE_DESCRIPTION("Timer LED trigger");
+MODULE_LICENSE("GPL v2");