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, 165 insertions, 0 deletions

diff --git a/drivers/extcon/extcon-gpio.c b/drivers/extcon/extcon-gpio.c
new file mode 100644
index 000000000..4105df74f
--- /dev/null
+++ b/drivers/extcon/extcon-gpio.c
@@ -0,0 +1,165 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * extcon_gpio.c - Single-state GPIO extcon driver based on extcon class
+ *
+ * Copyright (C) 2008 Google, Inc.
+ * Author: Mike Lockwood <lockwood@android.com>
+ *
+ * Modified by MyungJoo Ham <myungjoo.ham@samsung.com> to support extcon
+ * (originally switch class is supported)
+ */
+
+#include <linux/devm-helpers.h>
+#include <linux/extcon-provider.h>
+#include <linux/gpio/consumer.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+/**
+ * struct gpio_extcon_data - A simple GPIO-controlled extcon device state container.
+ * @edev:		Extcon device.
+ * @work:		Work fired by the interrupt.
+ * @debounce_jiffies:	Number of jiffies to wait for the GPIO to stabilize, from the debounce
+ *			value.
+ * @gpiod:		GPIO descriptor for this external connector.
+ * @extcon_id:		The unique id of specific external connector.
+ * @debounce:		Debounce time for GPIO IRQ in ms.
+ * @check_on_resume:	Boolean describing whether to check the state of gpio
+ *			while resuming from sleep.
+ */
+struct gpio_extcon_data {
+	struct extcon_dev *edev;
+	struct delayed_work work;
+	unsigned long debounce_jiffies;
+	struct gpio_desc *gpiod;
+	unsigned int extcon_id;
+	unsigned long debounce;
+	bool check_on_resume;
+};
+
+static void gpio_extcon_work(struct work_struct *work)
+{
+	int state;
+	struct gpio_extcon_data	*data =
+		container_of(to_delayed_work(work), struct gpio_extcon_data,
+			     work);
+
+	state = gpiod_get_value_cansleep(data->gpiod);
+	extcon_set_state_sync(data->edev, data->extcon_id, state);
+}
+
+static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
+{
+	struct gpio_extcon_data *data = dev_id;
+
+	queue_delayed_work(system_power_efficient_wq, &data->work,
+			      data->debounce_jiffies);
+	return IRQ_HANDLED;
+}
+
+static int gpio_extcon_probe(struct platform_device *pdev)
+{
+	struct gpio_extcon_data *data;
+	struct device *dev = &pdev->dev;
+	unsigned long irq_flags;
+	int irq;
+	int ret;
+
+	data = devm_kzalloc(dev, sizeof(struct gpio_extcon_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	/*
+	 * FIXME: extcon_id represents the unique identifier of external
+	 * connectors such as EXTCON_USB, EXTCON_DISP_HDMI and so on. extcon_id
+	 * is necessary to register the extcon device. But, it's not yet
+	 * developed to get the extcon id from device-tree or others.
+	 * On later, it have to be solved.
+	 */
+	if (data->extcon_id > EXTCON_NONE)
+		return -EINVAL;
+
+	data->gpiod = devm_gpiod_get(dev, "extcon", GPIOD_IN);
+	if (IS_ERR(data->gpiod))
+		return PTR_ERR(data->gpiod);
+	irq = gpiod_to_irq(data->gpiod);
+	if (irq <= 0)
+		return irq;
+
+	/*
+	 * It is unlikely that this is an acknowledged interrupt that goes
+	 * away after handling, what we are looking for are falling edges
+	 * if the signal is active low, and rising edges if the signal is
+	 * active high.
+	 */
+	if (gpiod_is_active_low(data->gpiod))
+		irq_flags = IRQF_TRIGGER_FALLING;
+	else
+		irq_flags = IRQF_TRIGGER_RISING;
+
+	/* Allocate the memory of extcon devie and register extcon device */
+	data->edev = devm_extcon_dev_allocate(dev, &data->extcon_id);
+	if (IS_ERR(data->edev)) {
+		dev_err(dev, "failed to allocate extcon device\n");
+		return -ENOMEM;
+	}
+
+	ret = devm_extcon_dev_register(dev, data->edev);
+	if (ret < 0)
+		return ret;
+
+	ret = devm_delayed_work_autocancel(dev, &data->work, gpio_extcon_work);
+	if (ret)
+		return ret;
+
+	/*
+	 * Request the interrupt of gpio to detect whether external connector
+	 * is attached or detached.
+	 */
+	ret = devm_request_any_context_irq(dev, irq,
+					gpio_irq_handler, irq_flags,
+					pdev->name, data);
+	if (ret < 0)
+		return ret;
+
+	platform_set_drvdata(pdev, data);
+	/* Perform initial detection */
+	gpio_extcon_work(&data->work.work);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int gpio_extcon_resume(struct device *dev)
+{
+	struct gpio_extcon_data *data;
+
+	data = dev_get_drvdata(dev);
+	if (data->check_on_resume)
+		queue_delayed_work(system_power_efficient_wq,
+			&data->work, data->debounce_jiffies);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(gpio_extcon_pm_ops, NULL, gpio_extcon_resume);
+
+static struct platform_driver gpio_extcon_driver = {
+	.probe		= gpio_extcon_probe,
+	.driver		= {
+		.name	= "extcon-gpio",
+		.pm	= &gpio_extcon_pm_ops,
+	},
+};
+
+module_platform_driver(gpio_extcon_driver);
+
+MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
+MODULE_DESCRIPTION("GPIO extcon driver");
+MODULE_LICENSE("GPL");