drivers/gpu/drm/tilcdc/tilcdc_external.c

   1 /*
   2  * Copyright (C) 2015 Texas Instruments
   3  * Author: Jyri Sarha <[email protected]>
   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_of.h>
  14
  15 #include "tilcdc_drv.h"
  16 #include "tilcdc_external.h"
  17
  18 static const struct tilcdc_panel_info panel_info_tda998x = {
  19                 .ac_bias                = 255,
  20                 .ac_bias_intrpt         = 0,
  21                 .dma_burst_sz           = 16,
  22                 .bpp                    = 16,
  23                 .fdd                    = 0x80,
  24                 .tft_alt_mode           = 0,
  25                 .invert_pxl_clk         = 1,
  26                 .sync_edge              = 1,
  27                 .sync_ctrl              = 1,
  28                 .raster_order           = 0,
  29 };
  30
  31 static const struct tilcdc_panel_info panel_info_default = {
  32                 .ac_bias                = 255,
  33                 .ac_bias_intrpt         = 0,
  34                 .dma_burst_sz           = 16,
  35                 .bpp                    = 16,
  36                 .fdd                    = 0x80,
  37                 .tft_alt_mode           = 0,
  38                 .sync_edge              = 0,
  39                 .sync_ctrl              = 1,
  40                 .raster_order           = 0,
  41 };
  42
  43 static int tilcdc_external_mode_valid(struct drm_connector *connector,
  44                                       struct drm_display_mode *mode)
  45 {
  46         struct tilcdc_drm_private *priv = connector->dev->dev_private;
  47         int ret;
  48
  49         ret = tilcdc_crtc_mode_valid(priv->crtc, mode);
  50         if (ret != MODE_OK)
  51                 return ret;
  52
  53         BUG_ON(priv->external_connector != connector);
  54         BUG_ON(!priv->connector_funcs);
  55
  56         /* If the connector has its own mode_valid call it. */
  57         if (!IS_ERR(priv->connector_funcs) &&
  58             priv->connector_funcs->mode_valid)
  59                 return priv->connector_funcs->mode_valid(connector, mode);
  60
  61         return MODE_OK;
  62 }
  63
  64 static int tilcdc_add_external_connector(struct drm_device *dev,
  65                                          struct drm_connector *connector)
  66 {
  67         struct tilcdc_drm_private *priv = dev->dev_private;
  68         struct drm_connector_helper_funcs *connector_funcs;
  69
  70         /* There should never be more than one connector */
  71         if (WARN_ON(priv->external_connector))
  72                 return -EINVAL;
  73
  74         priv->external_connector = connector;
  75         connector_funcs = devm_kzalloc(dev->dev, sizeof(*connector_funcs),
  76                                        GFP_KERNEL);
  77         if (!connector_funcs)
  78                 return -ENOMEM;
  79
  80         /* connector->helper_private contains always struct
  81          * connector_helper_funcs pointer. For tilcdc crtc to have a
  82          * say if a specific mode is Ok, we need to install our own
  83          * helper functions. In our helper functions we copy
  84          * everything else but use our own mode_valid() (above).
  85          */
  86         if (connector->helper_private) {
  87                 priv->connector_funcs = connector->helper_private;
  88                 *connector_funcs = *priv->connector_funcs;
  89         } else {
  90                 priv->connector_funcs = ERR_PTR(-ENOENT);
  91         }
  92         connector_funcs->mode_valid = tilcdc_external_mode_valid;
  93         drm_connector_helper_add(connector, connector_funcs);
  94
  95         dev_dbg(dev->dev, "External connector '%s' connected\n",
  96                 connector->name);
  97
  98         return 0;
  99 }
 100
 101 static
 102 struct drm_connector *tilcdc_encoder_find_connector(struct drm_device *ddev,
 103                                                     struct drm_encoder *encoder)
 104 {
 105         struct drm_connector *connector;
 106         int i;
 107
 108         list_for_each_entry(connector, &ddev->mode_config.connector_list, head)
 109                 for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++)
 110                         if (connector->encoder_ids[i] == encoder->base.id)
 111                                 return connector;
 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         priv->external_encoder->bridge = bridge;
 171         bridge->encoder = priv->external_encoder;
 172
 173         ret = drm_bridge_attach(ddev, bridge);
 174         if (ret) {
 175                 dev_err(ddev->dev, "drm_bridge_attach() failed %d\n", ret);
 176                 return ret;
 177         }
 178
 179         tilcdc_crtc_set_panel_info(priv->crtc, &panel_info_default);
 180
 181         connector = tilcdc_encoder_find_connector(ddev, priv->external_encoder);
 182         if (!connector)
 183                 return -ENODEV;
 184
 185         ret = tilcdc_add_external_connector(ddev, connector);
 186
 187         return ret;
 188 }
 189
 190 static int tilcdc_node_has_port(struct device_node *dev_node)
 191 {
 192         struct device_node *node;
 193
 194         node = of_get_child_by_name(dev_node, "ports");
 195         if (!node)
 196                 node = of_get_child_by_name(dev_node, "port");
 197         if (!node)
 198                 return 0;
 199         of_node_put(node);
 200
 201         return 1;
 202 }
 203
 204 static
 205 struct device_node *tilcdc_get_remote_node(struct device_node *node)
 206 {
 207         struct device_node *ep;
 208         struct device_node *parent;
 209
 210         if (!tilcdc_node_has_port(node))
 211                 return NULL;
 212
 213         ep = of_graph_get_next_endpoint(node, NULL);
 214         if (!ep)
 215                 return NULL;
 216
 217         parent = of_graph_get_remote_port_parent(ep);
 218         of_node_put(ep);
 219
 220         return parent;
 221 }
 222
 223 int tilcdc_attach_external_device(struct drm_device *ddev)
 224 {
 225         struct tilcdc_drm_private *priv = ddev->dev_private;
 226         struct device_node *remote_node;
 227         struct drm_bridge *bridge;
 228         int ret;
 229
 230         remote_node = tilcdc_get_remote_node(ddev->dev->of_node);
 231         if (!remote_node)
 232                 return 0;
 233
 234         bridge = of_drm_find_bridge(remote_node);
 235         of_node_put(remote_node);
 236         if (!bridge)
 237                 return -EPROBE_DEFER;
 238
 239         priv->external_encoder = devm_kzalloc(ddev->dev,
 240                                               sizeof(*priv->external_encoder),
 241                                               GFP_KERNEL);
 242         if (!priv->external_encoder)
 243                 return -ENOMEM;
 244
 245         ret = drm_encoder_init(ddev, priv->external_encoder,
 246                                &tilcdc_external_encoder_funcs,
 247                                DRM_MODE_ENCODER_NONE, NULL);
 248         if (ret) {
 249                 dev_err(ddev->dev, "drm_encoder_init() failed %d\n", ret);
 250                 return ret;
 251         }
 252
 253         ret = tilcdc_attach_bridge(ddev, bridge);
 254         if (ret)
 255                 drm_encoder_cleanup(priv->external_encoder);
 256
 257         return ret;
 258 }
 259
 260 static int dev_match_of(struct device *dev, void *data)
 261 {
 262         return dev->of_node == data;
 263 }
 264
 265 int tilcdc_get_external_components(struct device *dev,
 266                                    struct component_match **match)
 267 {
 268         struct device_node *node;
 269         struct device_node *ep = NULL;
 270         int count = 0;
 271         int ret = 0;
 272
 273         if (!tilcdc_node_has_port(dev->of_node))
 274                 return 0;
 275
 276         while ((ep = of_graph_get_next_endpoint(dev->of_node, ep))) {
 277                 node = of_graph_get_remote_port_parent(ep);
 278                 if (!node || !of_device_is_available(node)) {
 279                         of_node_put(node);
 280                         continue;
 281                 }
 282
 283                 dev_dbg(dev, "Subdevice node '%s' found\n", node->name);
 284
 285                 if (of_device_is_compatible(node, "nxp,tda998x")) {
 286                         if (match)
 287                                 drm_of_component_match_add(dev, match,
 288                                                            dev_match_of, node);
 289                         ret = 1;
 290                 }
 291
 292                 of_node_put(node);
 293                 if (count++ > 1) {
 294                         dev_err(dev, "Only one port is supported\n");
 295                         return -EINVAL;
 296                 }
 297         }
 298
 299         return ret;
 300 }