evdi_encoder.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012 Red Hat
 * Copyright (c) 2015 - 2020 DisplayLink (UK) Ltd.
 *
 * Based on parts on udlfb.c:
 * Copyright (C) 2009 its respective authors
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License v2. See the file COPYING in the main directory of this archive for
 * more details.
 */

#include <linux/version.h>
#if KERNEL_VERSION(5, 5, 0) <= LINUX_VERSION_CODE || defined(EL8)
#else
#include <drm/drmP.h>
#endif
#include <drm/drm_crtc.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_encoder.h>
#include <drm/drm_modeset_helper_vtables.h>
#include "evdi_drm_drv.h"

/* dummy encoder */
static void evdi_enc_destroy(struct drm_encoder *encoder)
{
	drm_encoder_cleanup(encoder);
	kfree(encoder);
}

static void evdi_encoder_enable(__always_unused struct drm_encoder *encoder)
{
}

static void evdi_encoder_disable(__always_unused struct drm_encoder *encoder)
{
}

static const struct drm_encoder_helper_funcs evdi_enc_helper_funcs = {
	.enable = evdi_encoder_enable,
	.disable = evdi_encoder_disable
};

static const struct drm_encoder_funcs evdi_enc_funcs = {
	.destroy = evdi_enc_destroy,
};

struct drm_encoder *evdi_encoder_init(struct drm_device *dev)
{
	struct drm_encoder *encoder;
	int ret = 0;

	encoder = kzalloc(sizeof(struct drm_encoder), GFP_KERNEL);
	if (!encoder)
		goto err;

	ret = drm_encoder_init(dev, encoder, &evdi_enc_funcs,
			       DRM_MODE_ENCODER_TMDS, "%s", dev_name(dev->dev));
	if (ret) {
		EVDI_ERROR("Failed to initialize encoder: %d\n", ret);
		goto err_encoder;
	}

	drm_encoder_helper_add(encoder, &evdi_enc_helper_funcs);

	encoder->possible_crtcs = 1;
	return encoder;

err_encoder:
	kfree(encoder);
err:
	return NULL;
}