drivers/gpu/drm/tilcdc/tilcdc_external.c

   1 /*
   2  * Copyright (C) 2015 Texas Instruments
   3  * Author: Jyri Sarha <jsarha@ti.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  *
   9  */
  10
  11 #include <linux/component.h>
  12 #include <linux/of_graph.h>
  13 #include <drm/drm_atomic_helper.h>
  14 #include <drm/drm_of.h>
  15
  16 #include "tilcdc_drv.h"
  17 #include "tilcdc_external.h"
  18
  19 static const struct tilcdc_panel_info panel_info_tda998x = {
  20                 .ac_bias                = 255,
  21                 .ac_bias_intrpt         = 0,
  22                 .dma_burst_sz           = 16,
  23                 .bpp                    = 16,
  24                 .fdd                    = 0x80,
  25                 .tft_alt_mode           = 0,
  26                 .invert_pxl_clk         = 1,
  27                 .sync_edge              = 1,
  28                 .sync_ctrl              = 1,
  29                 .raster_order           = 0,
  30 };
  31
  32 static const struct tilcdc_panel_info panel_info_default = {
  33                 .ac_bias                = 255,
  34                 .ac_bias_intrpt         = 0,
  35                 .dma_burst_sz           = 16,
  36                 .bpp                    = 16,
  37                 .fdd                    = 0x80,
  38                 .tft_alt_mode           = 0,
  39                 .sync_edge              = 0,
  40                 .sync_ctrl              = 1,
  41                 .raster_order           = 0,
  42 };
  43
  44 static int tilcdc_external_mode_valid(struct drm_connector *connector,
  45                                       struct drm_display_mode *mode)
  46 {
  47         struct tilcdc_drm_private *priv = connector->dev->dev_private;
  48         int ret;
  49
  50         ret = tilcdc_crtc_mode_valid(priv->crtc, mode);
  51         if (ret != MODE_OK)
  52                 return ret;
  53
  54         BUG_ON(priv->external_connector != connector);
  55         BUG_ON(!priv->connector_funcs);
  56
  57         /* If the connector has its own mode_valid call it. */
  58         if (!IS_ERR(priv->connector_funcs) &&
  59             priv->connector_funcs->mode_valid)
  60                 return priv->connector_funcs->mode_valid(connector, mode);
  61
  62         return MODE_OK;
  63 }
  64
  65 static int tilcdc_add_external_connector(struct drm_device *dev,
  66                                          struct drm_connector *connector)
  67 {
  68         struct tilcdc_drm_private *priv = dev->dev_private;
  69         struct drm_connector_helper_funcs *connector_funcs;
  70
  71         /* There should never be more than one connector */
  72         if (WARN_ON(priv->external_connector))
  73                 return -EINVAL;
  74
  75         priv->external_connector = connector;
  76         connector_funcs = devm_kzalloc(dev->dev, sizeof(*connector_funcs),
  77                                        GFP_KERNEL);
  78         if (!connector_funcs)
  79                 return -ENOMEM;
  80
  81         /* connector->helper_private contains always struct
  82          * connector_helper_funcs pointer. For tilcdc crtc to have a
  83          * say if a specific mode is Ok, we need to install our own
  84          * helper functions. In our helper functions we copy
  85          * everything else but use our own mode_valid() (above).
  86          */
  87         if (connector->helper_private) {
  88                 priv->connector_funcs = connector->helper_private;
  89                 *connector_funcs = *priv->connector_funcs;
  90         } else {
  91                 priv->connector_funcs = ERR_PTR(-ENOENT);
  92         }
  93         connector_funcs->mode_valid = tilcdc_external_mode_valid;
  94         drm_connector_helper_add(connector, connector_funcs);
  95
  96         dev_dbg(dev->dev, "External connector '%s' connected\n",
  97                 connector->name);
  98
  99         return 0;
 100 }
 101
 102 static
 103 struct drm_connector *tilcdc_encoder_find_connector(struct drm_device *ddev,
 104                                                     struct drm_encoder *encoder)
 105 {
 106         struct drm_connector *connector;
 107
 108         list_for_each_entry(connector, &ddev->mode_config.connector_list, head) {
 109                 if (drm_connector_has_possible_encoder(connector, encoder))
 110                         return connector;
 111         }
 112
 113         dev_err(ddev->dev, "No connector found for %s encoder (id %d)\n",
 114                 encoder->name, encoder->base.id);
 115
 116         return NULL;
 117 }
 118
 119 int tilcdc_add_component_encoder(struct drm_device *ddev)
 120 {
 121         struct tilcdc_drm_private *priv = ddev->dev_private;
 122         struct drm_connector *connector;
 123         struct drm_encoder *encoder;
 124
 125         list_for_each_entry(encoder, &ddev->mode_config.encoder_list, head)
 126                 if (encoder->possible_crtcs & (1 << priv->crtc->index))
 127                         break;
 128
 129         if (!encoder) {
 130                 dev_err(ddev->dev, "%s: No suitable encoder found\n", __func__);
 131                 return -ENODEV;
 132         }
 133
 134         connector = tilcdc_encoder_find_connector(ddev, encoder);
 135
 136         if (!connector)
 137                 return -ENODEV;
 138
 139         /* Only tda998x is supported at the moment. */
 140         tilcdc_crtc_set_simulate_vesa_sync(priv->crtc, true);
 141         tilcdc_crtc_set_panel_info(priv->crtc, &panel_info_tda998x);
 142
 143         return tilcdc_add_external_connector(ddev, connector);
 144 }
 145
 146 void tilcdc_remove_external_device(struct drm_device *dev)
 147 {
 148         struct tilcdc_drm_private *priv = dev->dev_private;
 149
 150         /* Restore the original helper functions, if any. */
 151         if (IS_ERR(priv->connector_funcs))
 152                 drm_connector_helper_add(priv->external_connector, NULL);
 153         else if (priv->connector_funcs)
 154                 drm_connector_helper_add(priv->external_connector,
 155                                          priv->connector_funcs);
 156 }
 157
 158 static const struct drm_encoder_funcs tilcdc_external_encoder_funcs = {
 159         .destroy        = drm_encoder_cleanup,
 160 };
 161
 162 static
 163 int tilcdc_attach_bridge(struct drm_device *ddev, struct drm_bridge *bridge)
 164 {
 165         struct tilcdc_drm_private *priv = ddev->dev_private;
 166         struct drm_connector *connector;
 167         int ret;
 168
 169         priv->external_encoder->possible_crtcs = BIT(0);
 170
 171         ret = drm_bridge_attach(priv->external_encoder, bridge, NULL);
 172         if (ret) {
 173                 dev_err(ddev->dev, "drm_bridge_attach() failed %d\n", ret);
 174                 return ret;
 175         }
 176
 177         tilcdc_crtc_set_panel_info(priv->crtc, &panel_info_default);
 178
 179         connector = tilcdc_encoder_find_connector(ddev, priv->external_encoder);
 180         if (!connector)
 181                 return -ENODEV;
 182
 183         ret = tilcdc_add_external_connector(ddev, connector);
 184
 185         return ret;
 186 }
 187
 188 int tilcdc_attach_external_device(struct drm_device *ddev)
 189 {
 190         struct tilcdc_drm_private *priv = ddev->dev_private;
 191         struct drm_bridge *bridge;
 192         struct drm_panel *panel;
 193         int ret;
 194
 195         ret = drm_of_find_panel_or_bridge(ddev->dev->of_node, 0, 0,
 196                                           &panel, &bridge);
 197         if (ret == -ENODEV)
 198                 return 0;
 199         else if (ret)
 200                 return ret;
 201
 202         priv->external_encoder = devm_kzalloc(ddev->dev,
 203                                               sizeof(*priv->external_encoder),
 204                                               GFP_KERNEL);
 205         if (!priv->external_encoder)
 206                 return -ENOMEM;
 207
 208         ret = drm_encoder_init(ddev, priv->external_encoder,
 209                                &tilcdc_external_encoder_funcs,
 210                                DRM_MODE_ENCODER_NONE, NULL);
 211         if (ret) {
 212                 dev_err(ddev->dev, "drm_encoder_init() failed %d\n", ret);
 213                 return ret;
 214         }
 215
 216         if (panel) {
 217                 bridge = devm_drm_panel_bridge_add(ddev->dev, panel,
 218                                                    DRM_MODE_CONNECTOR_DPI);
 219                 if (IS_ERR(bridge)) {
 220                         ret = PTR_ERR(bridge);
 221                         goto err_encoder_cleanup;
 222                 }
 223         }
 224
 225         ret = tilcdc_attach_bridge(ddev, bridge);
 226         if (ret)
 227                 goto err_encoder_cleanup;
 228
 229         return 0;
 230
 231 err_encoder_cleanup:
 232         drm_encoder_cleanup(priv->external_encoder);
 233         return ret;
 234 }
 235
 236 static int dev_match_of(struct device *dev, void *data)
 237 {
 238         return dev->of_node == data;
 239 }
 240
 241 int tilcdc_get_external_components(struct device *dev,
 242                                    struct component_match **match)
 243 {
 244         struct device_node *node;
 245
 246         node = of_graph_get_remote_node(dev->of_node, 0, 0);
 247
 248         if (!of_device_is_compatible(node, "nxp,tda998x")) {
 249                 of_node_put(node);
 250                 return 0;
 251         }
 252
 253         if (match)
 254                 drm_of_component_match_add(dev, match, dev_match_of, node);
 255         of_node_put(node);
 256         return 1;
 257 }