alistair23-linux/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c

/*
 * Copyright 2015 Freescale Semiconductor, Inc.
 *
 * Freescale DCU drm device driver
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/backlight.h>

#include <drm/drmP.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_panel.h>

#include "fsl_dcu_drm_drv.h"
#include "fsl_tcon.h"

static int
fsl_dcu_drm_encoder_atomic_check(struct drm_encoder *encoder,
				 struct drm_crtc_state *crtc_state,
				 struct drm_connector_state *conn_state)
{
	return 0;
}

static void fsl_dcu_drm_encoder_disable(struct drm_encoder *encoder)
{
	struct drm_device *dev = encoder->dev;
	struct fsl_dcu_drm_device *fsl_dev = dev->dev_private;

	if (fsl_dev->tcon)
		fsl_tcon_bypass_disable(fsl_dev->tcon);
}

static void fsl_dcu_drm_encoder_enable(struct drm_encoder *encoder)
{
	struct drm_device *dev = encoder->dev;
	struct fsl_dcu_drm_device *fsl_dev = dev->dev_private;

	if (fsl_dev->tcon)
		fsl_tcon_bypass_enable(fsl_dev->tcon);
}

static const struct drm_encoder_helper_funcs encoder_helper_funcs = {
	.atomic_check = fsl_dcu_drm_encoder_atomic_check,
	.disable = fsl_dcu_drm_encoder_disable,
	.enable = fsl_dcu_drm_encoder_enable,
};

static void fsl_dcu_drm_encoder_destroy(struct drm_encoder *encoder)
{
	drm_encoder_cleanup(encoder);
}

static const struct drm_encoder_funcs encoder_funcs = {
	.destroy = fsl_dcu_drm_encoder_destroy,
};

int fsl_dcu_drm_encoder_create(struct fsl_dcu_drm_device *fsl_dev,
			       struct drm_crtc *crtc)
{
	struct drm_encoder *encoder = &fsl_dev->encoder;
	int ret;

	encoder->possible_crtcs = 1;
	ret = drm_encoder_init(fsl_dev->drm, encoder, &encoder_funcs,
			       DRM_MODE_ENCODER_LVDS, NULL);
	if (ret < 0)
		return ret;

	drm_encoder_helper_add(encoder, &encoder_helper_funcs);

	return 0;
}

static void fsl_dcu_drm_connector_destroy(struct drm_connector *connector)
{
	struct fsl_dcu_drm_connector *fsl_con = to_fsl_dcu_connector(connector);

	drm_connector_unregister(connector);
	drm_panel_detach(fsl_con->panel);
	drm_connector_cleanup(connector);
}

static enum drm_connector_status
fsl_dcu_drm_connector_detect(struct drm_connector *connector, bool force)
{
	return connector_status_connected;
}

static const struct drm_connector_funcs fsl_dcu_drm_connector_funcs = {
	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
	.destroy = fsl_dcu_drm_connector_destroy,
	.detect = fsl_dcu_drm_connector_detect,
	.dpms = drm_atomic_helper_connector_dpms,
	.fill_modes = drm_helper_probe_single_connector_modes,
	.reset = drm_atomic_helper_connector_reset,
};

static struct drm_encoder *
fsl_dcu_drm_connector_best_encoder(struct drm_connector *connector)
{
	struct fsl_dcu_drm_connector *fsl_con = to_fsl_dcu_connector(connector);

	return fsl_con->encoder;
}

static int fsl_dcu_drm_connector_get_modes(struct drm_connector *connector)
{
	struct fsl_dcu_drm_connector *fsl_connector;
	int (*get_modes)(struct drm_panel *panel);
	int num_modes = 0;

	fsl_connector = to_fsl_dcu_connector(connector);
	if (fsl_connector->panel && fsl_connector->panel->funcs &&
	    fsl_connector->panel->funcs->get_modes) {
		get_modes = fsl_connector->panel->funcs->get_modes;
		num_modes = get_modes(fsl_connector->panel);
	}

	return num_modes;
}

static int fsl_dcu_drm_connector_mode_valid(struct drm_connector *connector,
					    struct drm_display_mode *mode)
{
	if (mode->hdisplay & 0xf)
		return MODE_ERROR;

	return MODE_OK;
}

static const struct drm_connector_helper_funcs connector_helper_funcs = {
	.best_encoder = fsl_dcu_drm_connector_best_encoder,
	.get_modes = fsl_dcu_drm_connector_get_modes,
	.mode_valid = fsl_dcu_drm_connector_mode_valid,
};

int fsl_dcu_drm_connector_create(struct fsl_dcu_drm_device *fsl_dev,
				 struct drm_encoder *encoder)
{
	struct drm_connector *connector = &fsl_dev->connector.base;
	struct drm_mode_config *mode_config = &fsl_dev->drm->mode_config;
	struct device_node *panel_node;
	int ret;

	fsl_dev->connector.encoder = encoder;

	ret = drm_connector_init(fsl_dev->drm, connector,
				 &fsl_dcu_drm_connector_funcs,
				 DRM_MODE_CONNECTOR_LVDS);
	if (ret < 0)
		return ret;

	drm_connector_helper_add(connector, &connector_helper_funcs);
	ret = drm_connector_register(connector);
	if (ret < 0)
		goto err_cleanup;

	ret = drm_mode_connector_attach_encoder(connector, encoder);
	if (ret < 0)
		goto err_sysfs;

	drm_object_property_set_value(&connector->base,
				      mode_config->dpms_property,
				      DRM_MODE_DPMS_OFF);

	panel_node = of_parse_phandle(fsl_dev->np, "fsl,panel", 0);
	if (!panel_node) {
		dev_err(fsl_dev->dev, "fsl,panel property not found\n");
		ret = -ENODEV;
		goto err_sysfs;
	}

	fsl_dev->connector.panel = of_drm_find_panel(panel_node);
	if (!fsl_dev->connector.panel) {
		ret = -EPROBE_DEFER;
		goto err_panel;
	}
	of_node_put(panel_node);

	ret = drm_panel_attach(fsl_dev->connector.panel, connector);
	if (ret) {
		dev_err(fsl_dev->dev, "failed to attach panel\n");
		goto err_sysfs;
	}

	return 0;

err_panel:
	of_node_put(panel_node);
err_sysfs:
	drm_connector_unregister(connector);
err_cleanup:
	drm_connector_cleanup(connector);
	return ret;
}