diff options
Diffstat (limited to 'drivers/gpu/drm/msm/dp/dp_drm.c')
| -rw-r--r-- | drivers/gpu/drm/msm/dp/dp_drm.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/drivers/gpu/drm/msm/dp/dp_drm.c b/drivers/gpu/drm/msm/dp/dp_drm.c new file mode 100644 index 000000000..6db82f9b0 --- /dev/null +++ b/drivers/gpu/drm/msm/dp/dp_drm.c @@ -0,0 +1,178 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2017-2020, The Linux Foundation. All rights reserved. + */ + +#include <drm/drm_atomic_helper.h> +#include <drm/drm_atomic.h> +#include <drm/drm_bridge.h> +#include <drm/drm_bridge_connector.h> +#include <drm/drm_crtc.h> + +#include "msm_drv.h" +#include "msm_kms.h" +#include "dp_drm.h" + +/** + * dp_bridge_detect - callback to determine if connector is connected + * @bridge: Pointer to drm bridge structure + * Returns: Bridge's 'is connected' status + */ +static enum drm_connector_status dp_bridge_detect(struct drm_bridge *bridge) +{ + struct msm_dp *dp; + + dp = to_dp_bridge(bridge)->dp_display; + + drm_dbg_dp(dp->drm_dev, "is_connected = %s\n", + (dp->is_connected) ? "true" : "false"); + + return (dp->is_connected) ? connector_status_connected : + connector_status_disconnected; +} + +static int dp_bridge_atomic_check(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state) +{ + struct msm_dp *dp; + + dp = to_dp_bridge(bridge)->dp_display; + + drm_dbg_dp(dp->drm_dev, "is_connected = %s\n", + (dp->is_connected) ? "true" : "false"); + + /* + * There is no protection in the DRM framework to check if the display + * pipeline has been already disabled before trying to disable it again. + * Hence if the sink is unplugged, the pipeline gets disabled, but the + * crtc->active is still true. Any attempt to set the mode or manually + * disable this encoder will result in the crash. + * + * TODO: add support for telling the DRM subsystem that the pipeline is + * disabled by the hardware and thus all access to it should be forbidden. + * After that this piece of code can be removed. + */ + if (bridge->ops & DRM_BRIDGE_OP_HPD) + return (dp->is_connected) ? 0 : -ENOTCONN; + + return 0; +} + + +/** + * dp_bridge_get_modes - callback to add drm modes via drm_mode_probed_add() + * @bridge: Poiner to drm bridge + * @connector: Pointer to drm connector structure + * Returns: Number of modes added + */ +static int dp_bridge_get_modes(struct drm_bridge *bridge, struct drm_connector *connector) +{ + int rc = 0; + struct msm_dp *dp; + + if (!connector) + return 0; + + dp = to_dp_bridge(bridge)->dp_display; + + /* pluggable case assumes EDID is read when HPD */ + if (dp->is_connected) { + rc = dp_display_get_modes(dp); + if (rc <= 0) { + DRM_ERROR("failed to get DP sink modes, rc=%d\n", rc); + return rc; + } + } else { + drm_dbg_dp(connector->dev, "No sink connected\n"); + } + return rc; +} + +static const struct drm_bridge_funcs dp_bridge_ops = { + .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, + .atomic_reset = drm_atomic_helper_bridge_reset, + .enable = dp_bridge_enable, + .disable = dp_bridge_disable, + .post_disable = dp_bridge_post_disable, + .mode_set = dp_bridge_mode_set, + .mode_valid = dp_bridge_mode_valid, + .get_modes = dp_bridge_get_modes, + .detect = dp_bridge_detect, + .atomic_check = dp_bridge_atomic_check, +}; + +struct drm_bridge *dp_bridge_init(struct msm_dp *dp_display, struct drm_device *dev, + struct drm_encoder *encoder) +{ + int rc; + struct msm_dp_bridge *dp_bridge; + struct drm_bridge *bridge; + + dp_bridge = devm_kzalloc(dev->dev, sizeof(*dp_bridge), GFP_KERNEL); + if (!dp_bridge) + return ERR_PTR(-ENOMEM); + + dp_bridge->dp_display = dp_display; + + bridge = &dp_bridge->bridge; + bridge->funcs = &dp_bridge_ops; + bridge->type = dp_display->connector_type; + + /* + * Many ops only make sense for DP. Why? + * - Detect/HPD are used by DRM to know if a display is _physically_ + * there, not whether the display is powered on / finished initting. + * On eDP we assume the display is always there because you can't + * know until power is applied. If we don't implement the ops DRM will + * assume our display is always there. + * - Currently eDP mode reading is driven by the panel driver. This + * allows the panel driver to properly power itself on to read the + * modes. + */ + if (!dp_display->is_edp) { + bridge->ops = + DRM_BRIDGE_OP_DETECT | + DRM_BRIDGE_OP_HPD | + DRM_BRIDGE_OP_MODES; + } + + drm_bridge_add(bridge); + + rc = drm_bridge_attach(encoder, bridge, NULL, DRM_BRIDGE_ATTACH_NO_CONNECTOR); + if (rc) { + DRM_ERROR("failed to attach bridge, rc=%d\n", rc); + drm_bridge_remove(bridge); + + return ERR_PTR(rc); + } + + if (dp_display->next_bridge) { + rc = drm_bridge_attach(encoder, + dp_display->next_bridge, bridge, + DRM_BRIDGE_ATTACH_NO_CONNECTOR); + if (rc < 0) { + DRM_ERROR("failed to attach panel bridge: %d\n", rc); + drm_bridge_remove(bridge); + return ERR_PTR(rc); + } + } + + return bridge; +} + +/* connector initialization */ +struct drm_connector *dp_drm_connector_init(struct msm_dp *dp_display, struct drm_encoder *encoder) +{ + struct drm_connector *connector = NULL; + + connector = drm_bridge_connector_init(dp_display->drm_dev, encoder); + if (IS_ERR(connector)) + return connector; + + drm_connector_attach_encoder(connector, encoder); + + return connector; +} |