drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c

Source file repositories/reference/linux-study-clean/drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c
Extension
.c
Size
3715 bytes
Lines
141
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0+
/*
 * RZ/G2L Display Unit Encoder
 *
 * Copyright (C) 2023 Renesas Electronics Corporation
 *
 * Based on rcar_du_encoder.c
 */

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

#include <drm/drm_atomic_helper.h>
#include <drm/drm_bridge.h>
#include <drm/drm_bridge_connector.h>
#include <drm/drm_panel.h>

#include "rzg2l_du_drv.h"
#include "rzg2l_du_encoder.h"

/* -----------------------------------------------------------------------------
 * Encoder
 */

static unsigned int rzg2l_du_encoder_count_ports(struct device_node *node)
{
	struct device_node *ports;
	struct device_node *port;
	unsigned int num_ports = 0;

	ports = of_get_child_by_name(node, "ports");
	if (!ports)
		ports = of_node_get(node);

	for_each_child_of_node(ports, port) {
		if (of_node_name_eq(port, "port"))
			num_ports++;
	}

	of_node_put(ports);

	return num_ports;
}

static const struct drm_encoder_funcs rzg2l_du_encoder_funcs = {
};

static enum drm_mode_status
rzg2l_du_encoder_mode_valid(struct drm_encoder *encoder,
			    const struct drm_display_mode *mode)
{
	struct rzg2l_du_encoder *renc = to_rzg2l_encoder(encoder);
	struct rzg2l_du_device *rcdu = to_rzg2l_du_device(renc->base.dev);
	const struct rzg2l_du_device_info *info = rcdu->info;

	if (renc->output != RZG2L_DU_OUTPUT_DPAD0)
		return MODE_OK;

	if (mode->clock < info->mode_clock_min)
		return MODE_CLOCK_LOW;
	if (mode->clock > info->mode_clock_max)
		return MODE_CLOCK_HIGH;

	return MODE_OK;
}

static const struct drm_encoder_helper_funcs rzg2l_du_encoder_helper_funcs = {
	.mode_valid = rzg2l_du_encoder_mode_valid,
};

int rzg2l_du_encoder_init(struct rzg2l_du_device  *rcdu,
			  enum rzg2l_du_output output,
			  struct device_node *enc_node)
{
	struct rzg2l_du_encoder *renc;
	struct drm_connector *connector;
	struct drm_bridge *bridge __free(drm_bridge_put) = NULL;
	int ret;

	/*
	 * Locate the DRM bridge from the DT node. For the DPAD outputs, if the
	 * DT node has a single port, assume that it describes a panel and
	 * create a panel bridge.
	 */
	if (output == RZG2L_DU_OUTPUT_DPAD0 && rzg2l_du_encoder_count_ports(enc_node) == 1) {
		struct drm_panel *panel = of_drm_find_panel(enc_node);

		if (IS_ERR(panel))
			return PTR_ERR(panel);

Annotation

Implementation Notes