1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2017-2020, The Linux Foundation. All rights reserved. 4 */ 5 6 #include <drm/drm_atomic_helper.h> 7 #include <drm/drm_atomic.h> 8 #include <drm/drm_bridge.h> 9 #include <drm/drm_bridge_connector.h> 10 #include <drm/drm_crtc.h> 11 12 #include "msm_drv.h" 13 #include "msm_kms.h" 14 #include "dp_drm.h" 15 16 /** 17 * dp_bridge_detect - callback to determine if connector is connected 18 * @bridge: Pointer to drm bridge structure 19 * Returns: Bridge's 'is connected' status 20 */ 21 static enum drm_connector_status dp_bridge_detect(struct drm_bridge *bridge) 22 { 23 struct msm_dp *dp; 24 25 dp = to_dp_bridge(bridge)->dp_display; 26 27 drm_dbg_dp(dp->drm_dev, "link_ready = %s\n", 28 (dp->link_ready) ? "true" : "false"); 29 30 return (dp->link_ready) ? connector_status_connected : 31 connector_status_disconnected; 32 } 33 34 static int dp_bridge_atomic_check(struct drm_bridge *bridge, 35 struct drm_bridge_state *bridge_state, 36 struct drm_crtc_state *crtc_state, 37 struct drm_connector_state *conn_state) 38 { 39 struct msm_dp *dp; 40 41 dp = to_dp_bridge(bridge)->dp_display; 42 43 drm_dbg_dp(dp->drm_dev, "link_ready = %s\n", 44 (dp->link_ready) ? "true" : "false"); 45 46 /* 47 * There is no protection in the DRM framework to check if the display 48 * pipeline has been already disabled before trying to disable it again. 49 * Hence if the sink is unplugged, the pipeline gets disabled, but the 50 * crtc->active is still true. Any attempt to set the mode or manually 51 * disable this encoder will result in the crash. 52 * 53 * TODO: add support for telling the DRM subsystem that the pipeline is 54 * disabled by the hardware and thus all access to it should be forbidden. 55 * After that this piece of code can be removed. 56 */ 57 if (bridge->ops & DRM_BRIDGE_OP_HPD) 58 return (dp->link_ready) ? 0 : -ENOTCONN; 59 60 return 0; 61 } 62 63 64 /** 65 * dp_bridge_get_modes - callback to add drm modes via drm_mode_probed_add() 66 * @bridge: Poiner to drm bridge 67 * @connector: Pointer to drm connector structure 68 * Returns: Number of modes added 69 */ 70 static int dp_bridge_get_modes(struct drm_bridge *bridge, struct drm_connector *connector) 71 { 72 int rc = 0; 73 struct msm_dp *dp; 74 75 if (!connector) 76 return 0; 77 78 dp = to_dp_bridge(bridge)->dp_display; 79 80 /* pluggable case assumes EDID is read when HPD */ 81 if (dp->link_ready) { 82 rc = dp_display_get_modes(dp); 83 if (rc <= 0) { 84 DRM_ERROR("failed to get DP sink modes, rc=%d\n", rc); 85 return rc; 86 } 87 } else { 88 drm_dbg_dp(connector->dev, "No sink connected\n"); 89 } 90 return rc; 91 } 92 93 static void dp_bridge_debugfs_init(struct drm_bridge *bridge, struct dentry *root) 94 { 95 struct msm_dp *dp = to_dp_bridge(bridge)->dp_display; 96 97 dp_display_debugfs_init(dp, root, false); 98 } 99 100 static const struct drm_bridge_funcs dp_bridge_ops = { 101 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, 102 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, 103 .atomic_reset = drm_atomic_helper_bridge_reset, 104 .atomic_enable = dp_bridge_atomic_enable, 105 .atomic_disable = dp_bridge_atomic_disable, 106 .atomic_post_disable = dp_bridge_atomic_post_disable, 107 .mode_set = dp_bridge_mode_set, 108 .mode_valid = dp_bridge_mode_valid, 109 .get_modes = dp_bridge_get_modes, 110 .detect = dp_bridge_detect, 111 .atomic_check = dp_bridge_atomic_check, 112 .hpd_enable = dp_bridge_hpd_enable, 113 .hpd_disable = dp_bridge_hpd_disable, 114 .hpd_notify = dp_bridge_hpd_notify, 115 .debugfs_init = dp_bridge_debugfs_init, 116 }; 117 118 static int edp_bridge_atomic_check(struct drm_bridge *drm_bridge, 119 struct drm_bridge_state *bridge_state, 120 struct drm_crtc_state *crtc_state, 121 struct drm_connector_state *conn_state) 122 { 123 struct msm_dp *dp = to_dp_bridge(drm_bridge)->dp_display; 124 125 if (WARN_ON(!conn_state)) 126 return -ENODEV; 127 128 conn_state->self_refresh_aware = dp->psr_supported; 129 130 if (!conn_state->crtc || !crtc_state) 131 return 0; 132 133 if (crtc_state->self_refresh_active && !dp->psr_supported) 134 return -EINVAL; 135 136 return 0; 137 } 138 139 static void edp_bridge_atomic_enable(struct drm_bridge *drm_bridge, 140 struct drm_bridge_state *old_bridge_state) 141 { 142 struct drm_atomic_state *atomic_state = old_bridge_state->base.state; 143 struct drm_crtc *crtc; 144 struct drm_crtc_state *old_crtc_state; 145 struct msm_dp_bridge *dp_bridge = to_dp_bridge(drm_bridge); 146 struct msm_dp *dp = dp_bridge->dp_display; 147 148 /* 149 * Check the old state of the crtc to determine if the panel 150 * was put into psr state previously by the edp_bridge_atomic_disable. 151 * If the panel is in psr, just exit psr state and skip the full 152 * bridge enable sequence. 153 */ 154 crtc = drm_atomic_get_new_crtc_for_encoder(atomic_state, 155 drm_bridge->encoder); 156 if (!crtc) 157 return; 158 159 old_crtc_state = drm_atomic_get_old_crtc_state(atomic_state, crtc); 160 161 if (old_crtc_state && old_crtc_state->self_refresh_active) { 162 dp_display_set_psr(dp, false); 163 return; 164 } 165 166 dp_bridge_atomic_enable(drm_bridge, old_bridge_state); 167 } 168 169 static void edp_bridge_atomic_disable(struct drm_bridge *drm_bridge, 170 struct drm_bridge_state *old_bridge_state) 171 { 172 struct drm_atomic_state *atomic_state = old_bridge_state->base.state; 173 struct drm_crtc *crtc; 174 struct drm_crtc_state *new_crtc_state = NULL, *old_crtc_state = NULL; 175 struct msm_dp_bridge *dp_bridge = to_dp_bridge(drm_bridge); 176 struct msm_dp *dp = dp_bridge->dp_display; 177 178 crtc = drm_atomic_get_old_crtc_for_encoder(atomic_state, 179 drm_bridge->encoder); 180 if (!crtc) 181 goto out; 182 183 new_crtc_state = drm_atomic_get_new_crtc_state(atomic_state, crtc); 184 if (!new_crtc_state) 185 goto out; 186 187 old_crtc_state = drm_atomic_get_old_crtc_state(atomic_state, crtc); 188 if (!old_crtc_state) 189 goto out; 190 191 /* 192 * Set self refresh mode if current crtc state is active. 193 * 194 * If old crtc state is active, then this is a display disable 195 * call while the sink is in psr state. So, exit psr here. 196 * The eDP controller will be disabled in the 197 * edp_bridge_atomic_post_disable function. 198 * 199 * We observed sink is stuck in self refresh if psr exit is skipped 200 * when display disable occurs while the sink is in psr state. 201 */ 202 if (new_crtc_state->self_refresh_active) { 203 dp_display_set_psr(dp, true); 204 return; 205 } else if (old_crtc_state->self_refresh_active) { 206 dp_display_set_psr(dp, false); 207 return; 208 } 209 210 out: 211 dp_bridge_atomic_disable(drm_bridge, old_bridge_state); 212 } 213 214 static void edp_bridge_atomic_post_disable(struct drm_bridge *drm_bridge, 215 struct drm_bridge_state *old_bridge_state) 216 { 217 struct drm_atomic_state *atomic_state = old_bridge_state->base.state; 218 struct drm_crtc *crtc; 219 struct drm_crtc_state *new_crtc_state = NULL; 220 221 crtc = drm_atomic_get_old_crtc_for_encoder(atomic_state, 222 drm_bridge->encoder); 223 if (!crtc) 224 return; 225 226 new_crtc_state = drm_atomic_get_new_crtc_state(atomic_state, crtc); 227 if (!new_crtc_state) 228 return; 229 230 /* 231 * Self refresh mode is already set in edp_bridge_atomic_disable. 232 */ 233 if (new_crtc_state->self_refresh_active) 234 return; 235 236 dp_bridge_atomic_post_disable(drm_bridge, old_bridge_state); 237 } 238 239 /** 240 * edp_bridge_mode_valid - callback to determine if specified mode is valid 241 * @bridge: Pointer to drm bridge structure 242 * @info: display info 243 * @mode: Pointer to drm mode structure 244 * Returns: Validity status for specified mode 245 */ 246 static enum drm_mode_status edp_bridge_mode_valid(struct drm_bridge *bridge, 247 const struct drm_display_info *info, 248 const struct drm_display_mode *mode) 249 { 250 struct msm_dp *dp; 251 int mode_pclk_khz = mode->clock; 252 253 dp = to_dp_bridge(bridge)->dp_display; 254 255 if (!dp || !mode_pclk_khz || !dp->connector) { 256 DRM_ERROR("invalid params\n"); 257 return -EINVAL; 258 } 259 260 if (mode->clock > DP_MAX_PIXEL_CLK_KHZ) 261 return MODE_CLOCK_HIGH; 262 263 /* 264 * The eDP controller currently does not have a reliable way of 265 * enabling panel power to read sink capabilities. So, we rely 266 * on the panel driver to populate only supported modes for now. 267 */ 268 return MODE_OK; 269 } 270 271 static void edp_bridge_debugfs_init(struct drm_bridge *bridge, struct dentry *root) 272 { 273 struct msm_dp *dp = to_dp_bridge(bridge)->dp_display; 274 275 dp_display_debugfs_init(dp, root, true); 276 } 277 278 static const struct drm_bridge_funcs edp_bridge_ops = { 279 .atomic_enable = edp_bridge_atomic_enable, 280 .atomic_disable = edp_bridge_atomic_disable, 281 .atomic_post_disable = edp_bridge_atomic_post_disable, 282 .mode_set = dp_bridge_mode_set, 283 .mode_valid = edp_bridge_mode_valid, 284 .atomic_reset = drm_atomic_helper_bridge_reset, 285 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, 286 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, 287 .atomic_check = edp_bridge_atomic_check, 288 .debugfs_init = edp_bridge_debugfs_init, 289 }; 290 291 int dp_bridge_init(struct msm_dp *dp_display, struct drm_device *dev, 292 struct drm_encoder *encoder) 293 { 294 int rc; 295 struct msm_dp_bridge *dp_bridge; 296 struct drm_bridge *bridge; 297 298 dp_bridge = devm_kzalloc(dev->dev, sizeof(*dp_bridge), GFP_KERNEL); 299 if (!dp_bridge) 300 return -ENOMEM; 301 302 dp_bridge->dp_display = dp_display; 303 304 bridge = &dp_bridge->bridge; 305 bridge->funcs = dp_display->is_edp ? &edp_bridge_ops : &dp_bridge_ops; 306 bridge->type = dp_display->connector_type; 307 308 /* 309 * Many ops only make sense for DP. Why? 310 * - Detect/HPD are used by DRM to know if a display is _physically_ 311 * there, not whether the display is powered on / finished initting. 312 * On eDP we assume the display is always there because you can't 313 * know until power is applied. If we don't implement the ops DRM will 314 * assume our display is always there. 315 * - Currently eDP mode reading is driven by the panel driver. This 316 * allows the panel driver to properly power itself on to read the 317 * modes. 318 */ 319 if (!dp_display->is_edp) { 320 bridge->ops = 321 DRM_BRIDGE_OP_DETECT | 322 DRM_BRIDGE_OP_HPD | 323 DRM_BRIDGE_OP_MODES; 324 } 325 326 rc = devm_drm_bridge_add(dev->dev, bridge); 327 if (rc) { 328 DRM_ERROR("failed to add bridge, rc=%d\n", rc); 329 330 return rc; 331 } 332 333 rc = drm_bridge_attach(encoder, bridge, NULL, DRM_BRIDGE_ATTACH_NO_CONNECTOR); 334 if (rc) { 335 DRM_ERROR("failed to attach bridge, rc=%d\n", rc); 336 337 return rc; 338 } 339 340 if (dp_display->next_bridge) { 341 rc = drm_bridge_attach(encoder, 342 dp_display->next_bridge, bridge, 343 DRM_BRIDGE_ATTACH_NO_CONNECTOR); 344 if (rc < 0) { 345 DRM_ERROR("failed to attach panel bridge: %d\n", rc); 346 return rc; 347 } 348 } 349 350 dp_display->bridge = bridge; 351 352 return 0; 353 } 354 355 /* connector initialization */ 356 struct drm_connector *dp_drm_connector_init(struct msm_dp *dp_display, struct drm_encoder *encoder, 357 bool yuv_supported) 358 { 359 struct drm_connector *connector = NULL; 360 361 connector = drm_bridge_connector_init(dp_display->drm_dev, encoder); 362 if (IS_ERR(connector)) 363 return connector; 364 365 if (!dp_display->is_edp) 366 drm_connector_attach_dp_subconnector_property(connector); 367 368 if (yuv_supported) 369 connector->ycbcr_420_allowed = true; 370 371 drm_connector_attach_encoder(connector, encoder); 372 373 return connector; 374 } 375