text: /*
   * Copyright (C) 2015 Free Electrons
   * Copyright (C) 2015 NextThing Co
   *
   * Maxime Ripard <maxime.ripard@free-electrons.com>
   *
   * 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/clk.h>
  
  #include <drm/drmP.h>
  #include <drm/drm_atomic_helper.h>
  #include <drm/drm_crtc_helper.h>
  #include <drm/drm_panel.h>
  
  #include "sun4i_drv.h"
  #include "sun4i_tcon.h"
  #include "sun4i_rgb.h"
  
  struct sun4i_rgb {
  	struct drm_connector	connector;
  	struct drm_encoder	encoder;
  
  	struct sun4i_drv	*drv;
  };
  
  static inline struct sun4i_rgb *
  drm_connector_to_sun4i_rgb(struct drm_connector *connector)
  {
  	return container_of(connector, struct sun4i_rgb,
  			    connector);
  }
  
  static inline struct sun4i_rgb *
  drm_encoder_to_sun4i_rgb(struct drm_encoder *encoder)
  {
  	return container_of(encoder, struct sun4i_rgb,
  			    encoder);
  }
  
  static int sun4i_rgb_get_modes(struct drm_connector *connector)
  {
  	struct sun4i_rgb *rgb =
  		drm_connector_to_sun4i_rgb(connector);
  	struct sun4i_drv *drv = rgb->drv;
  	struct sun4i_tcon *tcon = drv->tcon;
  
  	return drm_panel_get_modes(tcon->panel);
  }
  
  static int sun4i_rgb_mode_valid(struct drm_connector *connector,
  				struct drm_display_mode *mode)
  {
  	struct sun4i_rgb *rgb = drm_connector_to_sun4i_rgb(connector);
  	struct sun4i_drv *drv = rgb->drv;
  	struct sun4i_tcon *tcon = drv->tcon;
  	u32 hsync = mode->hsync_end - mode->hsync_start;
  	u32 vsync = mode->vsync_end - mode->vsync_start;
  	unsigned long rate = mode->clock * 1000;
  	long rounded_rate;
  
  	DRM_DEBUG_DRIVER("Validating modes...\n");
  
  	if (hsync < 1)
  		return MODE_HSYNC_NARROW;
  
  	if (hsync > 0x3ff)
  		return MODE_HSYNC_WIDE;
  
  	if ((mode->hdisplay < 1) || (mode->htotal < 1))
  		return MODE_H_ILLEGAL;
  
  	if ((mode->hdisplay > 0x7ff) || (mode->htotal > 0xfff))
  		return MODE_BAD_HVALUE;
  
  	DRM_DEBUG_DRIVER("Horizontal parameters OK\n");
  
  	if (vsync < 1)
  		return MODE_VSYNC_NARROW;
  
  	if (vsync > 0x3ff)
  		return MODE_VSYNC_WIDE;
  
  	if ((mode->vdisplay < 1) || (mode->vtotal < 1))
  		return MODE_V_ILLEGAL;
  
  	if ((mode->vdisplay > 0x7ff) || (mode->vtotal > 0xfff))
  		return MODE_BAD_VVALUE;
  
  	DRM_DEBUG_DRIVER("Vertical parameters OK\n");
  
  	rounded_rate = clk_round_rate(tcon->dclk, rate);
  	if (rounded_rate < rate)
  		return MODE_CLOCK_LOW;
  
  	if (rounded_rate > rate)
  		return MODE_CLOCK_HIGH;
  
  	DRM_DEBUG_DRIVER("Clock rate OK\n");
  
  	return MODE_OK;
  }
  
  static struct drm_connector_helper_funcs sun4i_rgb_con_helper_funcs = {
  	.get_modes	= sun4i_rgb_get_modes,
  	.mode_valid	= sun4i_rgb_mode_valid,
  };
  
  static enum drm_connector_status
  sun4i_rgb_connector_detect(struct drm_connector *connector, bool force)
  {
  	return connector_status_connected;
  }
  
  static void
  sun4i_rgb_connector_destroy(struct drm_connector *connector)
  {
  	struct sun4i_rgb *rgb = drm_connector_to_sun4i_rgb(connector);
  	struct sun4i_drv *drv = rgb->drv;
  	struct sun4i_tcon *tcon = drv->tcon;
  
  	drm_panel_detach(tcon->panel);
  	drm_connector_cleanup(connector);
  }
  
  static struct drm_connector_funcs sun4i_rgb_con_funcs = {
  	.dpms			= drm_atomic_helper_connector_dpms,
  	.detect			= sun4i_rgb_connector_detect,
  	.fill_modes		= drm_helper_probe_single_connector_modes,
  	.destroy		= sun4i_rgb_connector_destroy,
  	.reset			= drm_atomic_helper_connector_reset,
  	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
  	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
  };
  
  static int sun4i_rgb_atomic_check(struct drm_encoder *encoder,
  				  struct drm_crtc_state *crtc_state,
  				  struct drm_connector_state *conn_state)
  {
  	return 0;
  }
  
  static void sun4i_rgb_encoder_enable(struct drm_encoder *encoder)
  {
  	struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(encoder);
  	struct sun4i_drv *drv = rgb->drv;
  	struct sun4i_tcon *tcon = drv->tcon;
  
  	DRM_DEBUG_DRIVER("Enabling RGB output\n");
  
  	if (!IS_ERR(tcon->panel))
  		drm_panel_prepare(tcon->panel);
  
  	sun4i_tcon_channel_enable(tcon, 0);
  
  	if (!IS_ERR(tcon->panel))
  		drm_panel_enable(tcon->panel);
  }
  
  static void sun4i_rgb_encoder_disable(struct drm_encoder *encoder)
  {
  	struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(encoder);
  	struct sun4i_drv *drv = rgb->drv;
  	struct sun4i_tcon *tcon = drv->tcon;
  
  	DRM_DEBUG_DRIVER("Disabling RGB output\n");
  
  	if (!IS_ERR(tcon->panel))
  		drm_panel_disable(tcon->panel);
  
  	sun4i_tcon_channel_disable(tcon, 0);
  
  	if (!IS_ERR(tcon->panel))
  		drm_panel_unprepare(tcon->panel);
  }
  
  static void sun4i_rgb_encoder_mode_set(struct drm_encoder *encoder,
  				       struct drm_display_mode *mode,
  				       struct drm_display_mode *adjusted_mode)
  {
  	struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(encoder);
  	struct sun4i_drv *drv = rgb->drv;
  	struct sun4i_tcon *tcon = drv->tcon;
  
  	sun4i_tcon0_mode_set(tcon, mode);
  
  	clk_set_rate(tcon->dclk, mode->crtc_clock * 1000);
  
  	/* FIXME: This seems to be board specific */
  	clk_set_phase(tcon->dclk, 120);
  }
  
  static struct drm_encoder_helper_funcs sun4i_rgb_enc_helper_funcs = {
  	.atomic_check	= sun4i_rgb_atomic_check,
  	.mode_set	= sun4i_rgb_encoder_mode_set,
  	.disable	= sun4i_rgb_encoder_disable,
  	.enable		= sun4i_rgb_encoder_enable,
  };
  
  static void sun4i_rgb_enc_destroy(struct drm_encoder *encoder)
  {
  	drm_encoder_cleanup(encoder);
  }
  
  static struct drm_encoder_funcs sun4i_rgb_enc_funcs = {
  	.destroy	= sun4i_rgb_enc_destroy,
  };
  
  int sun4i_rgb_init(struct drm_device *drm)
  {
  	struct sun4i_drv *drv = drm->dev_private;
  	struct sun4i_tcon *tcon = drv->tcon;
  	struct drm_encoder *encoder;
  	struct sun4i_rgb *rgb;
  	int ret;
  
  	rgb = devm_kzalloc(drm->dev, sizeof(*rgb), GFP_KERNEL);
  	if (!rgb)
  		return -ENOMEM;
  	rgb->drv = drv;
  	encoder = &rgb->encoder;
  
  	tcon->panel = sun4i_tcon_find_panel(tcon->dev->of_node);
  	encoder->bridge = sun4i_tcon_find_bridge(tcon->dev->of_node);
  	if (IS_ERR(tcon->panel) && IS_ERR(encoder->bridge)) {
  		dev_info(drm->dev, "No panel or bridge found... RGB output disabled\n");
  		return 0;
  	}
  
  	drm_encoder_helper_add(&rgb->encoder,
  			       &sun4i_rgb_enc_helper_funcs);
  	ret = drm_encoder_init(drm,
  			       &rgb->encoder,
  			       &sun4i_rgb_enc_funcs,
  			       DRM_MODE_ENCODER_NONE,
  			       NULL);
  	if (ret) {
  		dev_err(drm->dev, "Couldn't initialise the rgb encoder\n");
  		goto err_out;
  	}
  
  	/* The RGB encoder can only work with the TCON channel 0 */
  	rgb->encoder.possible_crtcs = BIT(0);
  
  	if (!IS_ERR(tcon->panel)) {
  		drm_connector_helper_add(&rgb->connector,
  					 &sun4i_rgb_con_helper_funcs);
  		ret = drm_connector_init(drm, &rgb->connector,
  					 &sun4i_rgb_con_funcs,
  					 DRM_MODE_CONNECTOR_Unknown);
  		if (ret) {
  			dev_err(drm->dev, "Couldn't initialise the rgb connector\n");
  			goto err_cleanup_connector;
  		}
  
  		drm_mode_connector_attach_encoder(&rgb->connector,
  						  &rgb->encoder);
  
  		ret = drm_panel_attach(tcon->panel, &rgb->connector);
  		if (ret) {
  			dev_err(drm->dev, "Couldn't attach our panel\n");
  			goto err_cleanup_connector;
  		}
  	}
  
  	if (!IS_ERR(encoder->bridge)) {
  		encoder->bridge->encoder = &rgb->encoder;
  
  		ret = drm_bridge_attach(drm, encoder->bridge);
  		if (ret) {
  			dev_err(drm->dev, "Couldn't attach our bridge\n");
  			goto err_cleanup_connector;
  		}
  	} else {
  		encoder->bridge = NULL;
  	}
  
  	return 0;
  
  err_cleanup_connector:
  	drm_encoder_cleanup(&rgb->encoder);
  err_out:
  	return ret;
  }
  EXPORT_SYMBOL(sun4i_rgb_init);
  