ack-tegra/drivers/gpu/drm/tegra/output.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012 Avionic Design GmbH
 * Copyright (C) 2012 NVIDIA CORPORATION.  All rights reserved.
 */

#include <linux/i2c.h>
#include <linux/of.h>

#include <drm/drm_atomic_helper.h>
#include <drm/drm_edid.h>
#include <drm/drm_of.h>
#include <drm/drm_panel.h>
#include <drm/drm_simple_kms_helper.h>

#include "drm.h"
#include "dc.h"

#include <media/cec-notifier.h>

static ssize_t state_show(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	int ret;
	struct notify_dev *sdev = (struct notify_dev *)
		dev_get_drvdata(dev);

	if (sdev->print_state) {
		ret = sdev->print_state(sdev, buf);
		if (ret >= 0)
			return ret;
	}
	return sprintf(buf, "%d\n", sdev->state);
}

static ssize_t name_show(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	int ret;
	struct notify_dev *sdev = (struct notify_dev *)
		dev_get_drvdata(dev);

	if (sdev->print_name) {
		ret = sdev->print_name(sdev, buf);
		if (ret >= 0)
			return ret;
	}
	return sprintf(buf, "%s\n", sdev->name);
}

static DEVICE_ATTR_RO(state);
static DEVICE_ATTR_RO(name);

static int create_switch_class(struct class **switch_class, atomic_t *switch_count)
{
	if (!*switch_class) {
		*switch_class = class_create("switch");
		if (IS_ERR(*switch_class))
			return PTR_ERR(*switch_class);
		atomic_set(switch_count, 0);
	}

	return 0;
}

static int disp_uevent_dev_register(struct notify_dev *sdev, struct class **switch_class, atomic_t *switch_count)
{
	int ret;

	if (!*switch_class) {
		ret = create_switch_class(switch_class, switch_count);
		if (ret != 0)
			return ret;
	}

	sdev->index = atomic_inc_return(switch_count);
	sdev->dev = device_create(*switch_class, NULL,
			MKDEV(0, sdev->index), NULL, sdev->name);
	if (IS_ERR(sdev->dev))
		return PTR_ERR(sdev->dev);

	ret = device_create_file(sdev->dev, &dev_attr_state);
	if (ret < 0)
		goto err_create_file_1;
	ret = device_create_file(sdev->dev, &dev_attr_name);
	if (ret < 0)
		goto err_create_file_2;

	dev_set_drvdata(sdev->dev, sdev);
	sdev->state = 0;
	return 0;

err_create_file_2:
	device_remove_file(sdev->dev, &dev_attr_state);
err_create_file_1:
	device_destroy(*switch_class, MKDEV(0, sdev->index));
	printk(KERN_ERR "switch: Failed to register driver %s\n", sdev->name);
	return ret;
}

static void disp_uevent_dev_unregister(struct notify_dev *sdev, struct class *switch_class)
{
	device_remove_file(sdev->dev, &dev_attr_name);
	device_remove_file(sdev->dev, &dev_attr_state);
	device_destroy(switch_class, MKDEV(0, sdev->index));
	dev_set_drvdata(sdev->dev, NULL);
}

static int notify_uevent_user(struct notify_dev *sdev, int state)
{
	char *envp[3];
	char name_buf[120];
	char state_buf[120];

	if (sdev == NULL)
		return -1;

	if (sdev->state != state)
		sdev->state = state;

	snprintf(name_buf, sizeof(name_buf), "SWITCH_NAME=%s", sdev->name);
	envp[0] = name_buf;
	snprintf(state_buf, sizeof(state_buf), "SWITCH_STATE=%d", sdev->state);
	envp[1] = state_buf;
	envp[2] = NULL;

	kobject_uevent_env(&sdev->dev->kobj, KOBJ_CHANGE, envp);

	return 0;
}

int tegra_output_connector_get_modes(struct drm_connector *connector)
{
	struct tegra_output *output = connector_to_output(connector);
	const struct drm_edid *drm_edid = NULL;
	int err = 0;

	/*
	 * If the panel provides one or more modes, use them exclusively and
	 * ignore any other means of obtaining a mode.
	 */
	if (output->panel) {
		err = drm_panel_get_modes(output->panel, connector);
		if (err > 0)
			return err;
	}

	if (output->drm_edid)
		drm_edid = drm_edid_dup(output->drm_edid);
	else if (output->ddc)
		drm_edid = drm_edid_read_ddc(connector, output->ddc);

	drm_edid_connector_update(connector, drm_edid);
	cec_notifier_set_phys_addr(output->cec,
				   connector->display_info.source_physical_address);

	err = drm_edid_connector_add_modes(connector);
	drm_edid_free(drm_edid);

	return err;
}

enum drm_connector_status
tegra_output_connector_detect(struct drm_connector *connector, bool force)
{
	struct tegra_output *output = connector_to_output(connector);
	enum drm_connector_status status = connector_status_unknown;

	if (output->hpd_gpio) {
		if (gpiod_get_value(output->hpd_gpio) == 0)
			status = connector_status_disconnected;
		else
			status = connector_status_connected;
	} else {
		if (!output->panel)
			status = connector_status_disconnected;
		else
			status = connector_status_connected;
	}

	if (status != connector_status_connected)
		cec_notifier_phys_addr_invalidate(output->cec);

	return status;
}

void tegra_output_connector_destroy(struct drm_connector *connector)
{
	struct tegra_output *output = connector_to_output(connector);

	if (output->cec)
		cec_notifier_conn_unregister(output->cec);

	drm_connector_unregister(connector);
	drm_connector_cleanup(connector);
}

static irqreturn_t hpd_irq(int irq, void *data)
{
	struct tegra_output *output = data;

	if (output->connector.dev) {
		drm_helper_hpd_irq_event(output->connector.dev);

		if (output->connector.connector_type == DRM_MODE_CONNECTOR_HDMIA ||
		    output->connector.connector_type == DRM_MODE_CONNECTOR_HDMIB)
			notify_uevent_user(&output->notify_data, (output->connector.status == connector_status_connected ? 1 : 0));
	}

	return IRQ_HANDLED;
}

int tegra_output_probe(struct tegra_output *output)
{
	struct device_node *ddc, *panel;
	const void *edid;
	unsigned long flags;
	int err, size;

	if (!output->of_node)
		output->of_node = output->dev->of_node;

	err = drm_of_find_panel_or_bridge(output->of_node, -1, -1,
					  &output->panel, &output->bridge);
	if (err && err != -ENODEV)
		return err;

	panel = of_parse_phandle(output->of_node, "nvidia,panel", 0);
	if (panel) {
		/*
		 * Don't mix nvidia,panel phandle with the graph in a
		 * device-tree.
		 */
		WARN_ON(output->panel || output->bridge);

		output->panel = of_drm_find_panel(panel);
		of_node_put(panel);

		if (IS_ERR(output->panel))
			return PTR_ERR(output->panel);
	}

	ddc = of_parse_phandle(output->of_node, "nvidia,ddc-i2c-bus", 0);
	if (ddc) {
		output->ddc = of_get_i2c_adapter_by_node(ddc);
		of_node_put(ddc);

		if (!output->ddc) {
			err = -EPROBE_DEFER;
			return err;
		}
	}

	edid = of_get_property(output->of_node, "nvidia,edid", &size);
	output->drm_edid = drm_edid_alloc(edid, size);

	output->hpd_gpio = devm_fwnode_gpiod_get(output->dev,
					of_fwnode_handle(output->of_node),
					"nvidia,hpd",
					GPIOD_IN,
					"HDMI hotplug detect");
	if (IS_ERR(output->hpd_gpio)) {
		if (PTR_ERR(output->hpd_gpio) != -ENOENT) {
			err = PTR_ERR(output->hpd_gpio);
			goto put_i2c;
		}

		output->hpd_gpio = NULL;
	}

	if (output->hpd_gpio) {
		err = gpiod_to_irq(output->hpd_gpio);
		if (err < 0) {
			dev_err(output->dev, "gpiod_to_irq(): %d\n", err);
			goto put_i2c;
		}

		output->hpd_irq = err;

		flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
			IRQF_ONESHOT;

		err = request_threaded_irq(output->hpd_irq, NULL, hpd_irq,
					   flags, "hpd", output);
		if (err < 0) {
			dev_err(output->dev, "failed to request IRQ#%u: %d\n",
				output->hpd_irq, err);
			goto put_i2c;
		}

		output->connector.polled = DRM_CONNECTOR_POLL_HPD;

		/*
		 * Disable the interrupt until the connector has been
		 * initialized to avoid a race in the hotplug interrupt
		 * handler.
		 */
		disable_irq(output->hpd_irq);
	}

	return 0;

put_i2c:
	if (output->ddc)
		i2c_put_adapter(output->ddc);

	drm_edid_free(output->drm_edid);

	return err;
}

void tegra_output_remove(struct tegra_output *output)
{
	if (output->hpd_gpio)
		free_irq(output->hpd_irq, output);

	if (output->ddc)
		i2c_put_adapter(output->ddc);

	drm_edid_free(output->drm_edid);
}

int tegra_output_init(struct drm_device *drm, struct tegra_output *output)
{
	int connector_type;
	int err;

	/*
	 * The connector is now registered and ready to receive hotplug events
	 * so the hotplug interrupt can be enabled.
	 */
	if (output->hpd_gpio)
		enable_irq(output->hpd_irq);

	connector_type = output->connector.connector_type;
	/*
	 * Create a CEC notifier for HDMI connector.
	 */
	if (connector_type == DRM_MODE_CONNECTOR_HDMIA ||
	    connector_type == DRM_MODE_CONNECTOR_HDMIB) {
		struct cec_connector_info conn_info;

		cec_fill_conn_info_from_drm(&conn_info, &output->connector);
		output->cec = cec_notifier_conn_register(output->dev, NULL,
							 &conn_info);
		if (!output->cec)
			return -ENOMEM;

		if (output->hpd_gpio) {
			output->notify_data.name = "hdmi";  // now hwc not support DP
			output->notify_data.index = 0;
			output->notify_data.state = 0;
			err = disp_uevent_dev_register(&output->notify_data, &output->switch_class, &output->switch_count);
			if (err < 0) {
				dev_err(output->dev, "switch_dev_register failed: %d\n", err);
				return err;
			}

			if (tegra_output_connector_detect(&output->connector, false) == connector_status_connected)
				notify_uevent_user(&output->notify_data, 1);
		}
	}

	return 0;
}

void tegra_output_exit(struct tegra_output *output)
{
	/*
	 * The connector is going away, so the interrupt must be disabled to
	 * prevent the hotplug interrupt handler from potentially crashing.
	 */
	if (output->hpd_gpio) {
		disable_irq(output->hpd_irq);
		disp_uevent_dev_unregister(&output->notify_data, output->switch_class);
	}
}

void tegra_output_find_possible_crtcs(struct tegra_output *output,
				      struct drm_device *drm)
{
	struct device *dev = output->dev;
	struct drm_crtc *crtc;
	unsigned int mask = 0;

	drm_for_each_crtc(crtc, drm) {
		struct tegra_dc *dc = to_tegra_dc(crtc);

		if (tegra_dc_has_output(dc, dev))
			mask |= drm_crtc_mask(crtc);
	}

	if (mask == 0) {
		dev_warn(dev, "missing output definition for heads in DT\n");
		mask = 0x3;
	}

	output->encoder.possible_crtcs = mask;
}

int tegra_output_suspend(struct tegra_output *output)
{
	if (output->hpd_irq)
		disable_irq(output->hpd_irq);

	return 0;
}

int tegra_output_resume(struct tegra_output *output)
{
	if (output->hpd_irq)
		enable_irq(output->hpd_irq);

	return 0;
}