Quelle  tilcdc_external.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2015 Texas Instruments
 * Author: Jyri Sarha <jsarha@ti.com>
 */

#include <linux/component.h>
#include <linux/of_graph.h>

#include <drm/drm_atomic_helper.h>
#include <drm/drm_bridge.h>
#include <drm/drm_of.h>
#include <drm/drm_simple_kms_helper.h>

#include "tilcdc_drv.h"
#include "tilcdc_external.h"

static const struct tilcdc_panel_info panel_info_tda998x = {
  .ac_bias                = 255,
  .ac_bias_intrpt         = 0,
  .dma_burst_sz           = 16,
  .bpp                    = 16,
  .fdd                    = 0x80,
  .tft_alt_mode           = 0,
  .invert_pxl_clk  = 1,
  .sync_edge              = 1,
  .sync_ctrl              = 1,
  .raster_order           = 0,
};

static const struct tilcdc_panel_info panel_info_default = {
  .ac_bias                = 255,
  .ac_bias_intrpt         = 0,
  .dma_burst_sz           = 16,
  .bpp                    = 16,
  .fdd                    = 0x80,
  .tft_alt_mode           = 0,
  .sync_edge              = 0,
  .sync_ctrl              = 1,
  .raster_order           = 0,
};

static
struct drm_connector *tilcdc_encoder_find_connector(struct drm_device *ddev,
          struct drm_encoder *encoder)
{
 struct drm_connector *connector;

 list_for_each_entry(connector, &ddev->mode_config.connector_list, head) {
  if (drm_connector_has_possible_encoder(connector, encoder))
   return connector;
 }

 dev_err(ddev->dev, "No connector found for %s encoder (id %d)\n",
  encoder->name, encoder->base.id);

 return NULL;
}

int tilcdc_add_component_encoder(struct drm_device *ddev)
{
 struct tilcdc_drm_private *priv = ddev->dev_private;
 struct drm_encoder *encoder = NULL, *iter;

 list_for_each_entry(iter, &ddev->mode_config.encoder_list, head)
  if (iter->possible_crtcs & (1 << priv->crtc->index)) {
   encoder = iter;
   break;
  }

 if (!encoder) {
  dev_err(ddev->dev, "%s: No suitable encoder found\n", __func__);
  return -ENODEV;
 }

 priv->external_connector =
  tilcdc_encoder_find_connector(ddev, encoder);

 if (!priv->external_connector)
  return -ENODEV;

 /* Only tda998x is supported at the moment. */
 tilcdc_crtc_set_simulate_vesa_sync(priv->crtc, true);
 tilcdc_crtc_set_panel_info(priv->crtc, &panel_info_tda998x);

 return 0;
}

static
int tilcdc_attach_bridge(struct drm_device *ddev, struct drm_bridge *bridge)
{
 struct tilcdc_drm_private *priv = ddev->dev_private;
 int ret;

 priv->external_encoder->possible_crtcs = BIT(0);

 ret = drm_bridge_attach(priv->external_encoder, bridge, NULL, 0);
 if (ret)
  return ret;

 tilcdc_crtc_set_panel_info(priv->crtc, &panel_info_default);

 priv->external_connector =
  tilcdc_encoder_find_connector(ddev, priv->external_encoder);
 if (!priv->external_connector)
  return -ENODEV;

 return 0;
}

int tilcdc_attach_external_device(struct drm_device *ddev)
{
 struct tilcdc_drm_private *priv = ddev->dev_private;
 struct drm_bridge *bridge;
 struct drm_panel *panel;
 int ret;

 ret = drm_of_find_panel_or_bridge(ddev->dev->of_node, 0, 0,
       &panel, &bridge);
 if (ret == -ENODEV)
  return 0;
 else if (ret)
  return ret;

 priv->external_encoder = devm_kzalloc(ddev->dev,
           sizeof(*priv->external_encoder),
           GFP_KERNEL);
 if (!priv->external_encoder)
  return -ENOMEM;

 ret = drm_simple_encoder_init(ddev, priv->external_encoder,
          DRM_MODE_ENCODER_NONE);
 if (ret) {
  dev_err(ddev->dev, "drm_encoder_init() failed %d\n", ret);
  return ret;
 }

 if (panel) {
  bridge = devm_drm_panel_bridge_add_typed(ddev->dev, panel,
        DRM_MODE_CONNECTOR_DPI);
  if (IS_ERR(bridge)) {
   ret = PTR_ERR(bridge);
   goto err_encoder_cleanup;
  }
 }

 ret = tilcdc_attach_bridge(ddev, bridge);
 if (ret)
  goto err_encoder_cleanup;

 return 0;

err_encoder_cleanup:
 drm_encoder_cleanup(priv->external_encoder);
 return ret;
}

static int dev_match_of(struct device *dev, void *data)
{
 return dev->of_node == data;
}

int tilcdc_get_external_components(struct device *dev,
       struct component_match **match)
{
 struct device_node *node;

 node = of_graph_get_remote_node(dev->of_node, 0, 0);

 if (!of_device_is_compatible(node, "nxp,tda998x")) {
  of_node_put(node);
  return 0;
 }

 if (match)
  drm_of_component_match_add(dev, match, dev_match_of, node);
 of_node_put(node);
 return 1;
}