Quelle  ast_vga.c   Sprache: C

// SPDX-License-Identifier: MIT

#include <drm/drm_atomic_state_helper.h>
#include <drm/drm_edid.h>
#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>

#include "ast_ddc.h"
#include "ast_drv.h"

/*
 * Encoder
 */

static const struct drm_encoder_funcs ast_vga_encoder_funcs = {
 .destroy = drm_encoder_cleanup,
};

/*
 * Connector
 */

static int ast_vga_connector_helper_get_modes(struct drm_connector *connector)
{
 struct ast_connector *ast_connector = to_ast_connector(connector);
 int count;

 if (ast_connector->physical_status == connector_status_connected) {
  count = drm_connector_helper_get_modes(connector);
 } else {
  drm_edid_connector_update(connector, NULL);

  /*
 * There's no EDID data without a connected monitor. Set BMC-
 * compatible modes in this case. The XGA default resolution
 * should work well for all BMCs.
 */
  count = drm_add_modes_noedid(connector, 4096, 4096);
  if (count)
   drm_set_preferred_mode(connector, 1024, 768);
 }

 return count;
}

static int ast_vga_connector_helper_detect_ctx(struct drm_connector *connector,
            struct drm_modeset_acquire_ctx *ctx,
            bool force)
{
 struct ast_connector *ast_connector = to_ast_connector(connector);
 enum drm_connector_status status;

 status = drm_connector_helper_detect_from_ddc(connector, ctx, force);

 if (status != ast_connector->physical_status)
  ++connector->epoch_counter;
 ast_connector->physical_status = status;

 return connector_status_connected;
}

static const struct drm_connector_helper_funcs ast_vga_connector_helper_funcs = {
 .get_modes = ast_vga_connector_helper_get_modes,
 .detect_ctx = ast_vga_connector_helper_detect_ctx,
};

static const struct drm_connector_funcs ast_vga_connector_funcs = {
 .reset = drm_atomic_helper_connector_reset,
 .fill_modes = drm_helper_probe_single_connector_modes,
 .destroy = drm_connector_cleanup,
 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
};

/*
 * Output
 */

int ast_vga_output_init(struct ast_device *ast)
{
 struct drm_device *dev = &ast->base;
 struct drm_crtc *crtc = &ast->crtc;
 struct i2c_adapter *ddc;
 struct drm_encoder *encoder;
 struct ast_connector *ast_connector;
 struct drm_connector *connector;
 int ret;

 /* DDC */

 ddc = ast_ddc_create(ast);
 if (IS_ERR(ddc))
  return PTR_ERR(ddc);

 /* encoder */

 encoder = &ast->output.vga.encoder;
 ret = drm_encoder_init(dev, encoder, &ast_vga_encoder_funcs,
          DRM_MODE_ENCODER_DAC, NULL);
 if (ret)
  return ret;
 encoder->possible_crtcs = drm_crtc_mask(crtc);

 /* connector */

 ast_connector = &ast->output.vga.connector;
 connector = &ast_connector->base;
 ret = drm_connector_init_with_ddc(dev, connector, &ast_vga_connector_funcs,
       DRM_MODE_CONNECTOR_VGA, ddc);
 if (ret)
  return ret;
 drm_connector_helper_add(connector, &ast_vga_connector_helper_funcs);

 connector->interlace_allowed = 0;
 connector->doublescan_allowed = 0;
 connector->polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;

 ast_connector->physical_status = connector->status;

 ret = drm_connector_attach_encoder(connector, encoder);
 if (ret)
  return ret;

 return 0;
}