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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/gpu/drm/drm_encoder.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/drm_encoder.c')
-rw-r--r--drivers/gpu/drm/drm_encoder.c246
1 files changed, 246 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_encoder.c b/drivers/gpu/drm/drm_encoder.c
new file mode 100644
index 000000000..273e1c59c
--- /dev/null
+++ b/drivers/gpu/drm/drm_encoder.c
@@ -0,0 +1,246 @@
+/*
+ * Copyright (c) 2016 Intel Corporation
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission. The copyright holders make no representations
+ * about the suitability of this software for any purpose. It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#include <linux/export.h>
+#include <drm/drmP.h>
+#include <drm/drm_encoder.h>
+
+#include "drm_crtc_internal.h"
+
+/**
+ * DOC: overview
+ *
+ * Encoders represent the connecting element between the CRTC (as the overall
+ * pixel pipeline, represented by &struct drm_crtc) and the connectors (as the
+ * generic sink entity, represented by &struct drm_connector). An encoder takes
+ * pixel data from a CRTC and converts it to a format suitable for any attached
+ * connector. Encoders are objects exposed to userspace, originally to allow
+ * userspace to infer cloning and connector/CRTC restrictions. Unfortunately
+ * almost all drivers get this wrong, making the uabi pretty much useless. On
+ * top of that the exposed restrictions are too simple for today's hardware, and
+ * the recommended way to infer restrictions is by using the
+ * DRM_MODE_ATOMIC_TEST_ONLY flag for the atomic IOCTL.
+ *
+ * Otherwise encoders aren't used in the uapi at all (any modeset request from
+ * userspace directly connects a connector with a CRTC), drivers are therefore
+ * free to use them however they wish. Modeset helper libraries make strong use
+ * of encoders to facilitate code sharing. But for more complex settings it is
+ * usually better to move shared code into a separate &drm_bridge. Compared to
+ * encoders, bridges also have the benefit of being purely an internal
+ * abstraction since they are not exposed to userspace at all.
+ *
+ * Encoders are initialized with drm_encoder_init() and cleaned up using
+ * drm_encoder_cleanup().
+ */
+static const struct drm_prop_enum_list drm_encoder_enum_list[] = {
+ { DRM_MODE_ENCODER_NONE, "None" },
+ { DRM_MODE_ENCODER_DAC, "DAC" },
+ { DRM_MODE_ENCODER_TMDS, "TMDS" },
+ { DRM_MODE_ENCODER_LVDS, "LVDS" },
+ { DRM_MODE_ENCODER_TVDAC, "TV" },
+ { DRM_MODE_ENCODER_VIRTUAL, "Virtual" },
+ { DRM_MODE_ENCODER_DSI, "DSI" },
+ { DRM_MODE_ENCODER_DPMST, "DP MST" },
+ { DRM_MODE_ENCODER_DPI, "DPI" },
+};
+
+int drm_encoder_register_all(struct drm_device *dev)
+{
+ struct drm_encoder *encoder;
+ int ret = 0;
+
+ drm_for_each_encoder(encoder, dev) {
+ if (encoder->funcs->late_register)
+ ret = encoder->funcs->late_register(encoder);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+void drm_encoder_unregister_all(struct drm_device *dev)
+{
+ struct drm_encoder *encoder;
+
+ drm_for_each_encoder(encoder, dev) {
+ if (encoder->funcs->early_unregister)
+ encoder->funcs->early_unregister(encoder);
+ }
+}
+
+/**
+ * drm_encoder_init - Init a preallocated encoder
+ * @dev: drm device
+ * @encoder: the encoder to init
+ * @funcs: callbacks for this encoder
+ * @encoder_type: user visible type of the encoder
+ * @name: printf style format string for the encoder name, or NULL for default name
+ *
+ * Initialises a preallocated encoder. Encoder should be subclassed as part of
+ * driver encoder objects. At driver unload time drm_encoder_cleanup() should be
+ * called from the driver's &drm_encoder_funcs.destroy hook.
+ *
+ * Returns:
+ * Zero on success, error code on failure.
+ */
+int drm_encoder_init(struct drm_device *dev,
+ struct drm_encoder *encoder,
+ const struct drm_encoder_funcs *funcs,
+ int encoder_type, const char *name, ...)
+{
+ int ret;
+
+ /* encoder index is used with 32bit bitmasks */
+ if (WARN_ON(dev->mode_config.num_encoder >= 32))
+ return -EINVAL;
+
+ ret = drm_mode_object_add(dev, &encoder->base, DRM_MODE_OBJECT_ENCODER);
+ if (ret)
+ return ret;
+
+ encoder->dev = dev;
+ encoder->encoder_type = encoder_type;
+ encoder->funcs = funcs;
+ if (name) {
+ va_list ap;
+
+ va_start(ap, name);
+ encoder->name = kvasprintf(GFP_KERNEL, name, ap);
+ va_end(ap);
+ } else {
+ encoder->name = kasprintf(GFP_KERNEL, "%s-%d",
+ drm_encoder_enum_list[encoder_type].name,
+ encoder->base.id);
+ }
+ if (!encoder->name) {
+ ret = -ENOMEM;
+ goto out_put;
+ }
+
+ list_add_tail(&encoder->head, &dev->mode_config.encoder_list);
+ encoder->index = dev->mode_config.num_encoder++;
+
+out_put:
+ if (ret)
+ drm_mode_object_unregister(dev, &encoder->base);
+
+ return ret;
+}
+EXPORT_SYMBOL(drm_encoder_init);
+
+/**
+ * drm_encoder_cleanup - cleans up an initialised encoder
+ * @encoder: encoder to cleanup
+ *
+ * Cleans up the encoder but doesn't free the object.
+ */
+void drm_encoder_cleanup(struct drm_encoder *encoder)
+{
+ struct drm_device *dev = encoder->dev;
+
+ /* Note that the encoder_list is considered to be static; should we
+ * remove the drm_encoder at runtime we would have to decrement all
+ * the indices on the drm_encoder after us in the encoder_list.
+ */
+
+ if (encoder->bridge) {
+ struct drm_bridge *bridge = encoder->bridge;
+ struct drm_bridge *next;
+
+ while (bridge) {
+ next = bridge->next;
+ drm_bridge_detach(bridge);
+ bridge = next;
+ }
+ }
+
+ drm_mode_object_unregister(dev, &encoder->base);
+ kfree(encoder->name);
+ list_del(&encoder->head);
+ dev->mode_config.num_encoder--;
+
+ memset(encoder, 0, sizeof(*encoder));
+}
+EXPORT_SYMBOL(drm_encoder_cleanup);
+
+static struct drm_crtc *drm_encoder_get_crtc(struct drm_encoder *encoder)
+{
+ struct drm_connector *connector;
+ struct drm_device *dev = encoder->dev;
+ bool uses_atomic = false;
+ struct drm_connector_list_iter conn_iter;
+
+ /* For atomic drivers only state objects are synchronously updated and
+ * protected by modeset locks, so check those first. */
+ drm_connector_list_iter_begin(dev, &conn_iter);
+ drm_for_each_connector_iter(connector, &conn_iter) {
+ if (!connector->state)
+ continue;
+
+ uses_atomic = true;
+
+ if (connector->state->best_encoder != encoder)
+ continue;
+
+ drm_connector_list_iter_end(&conn_iter);
+ return connector->state->crtc;
+ }
+ drm_connector_list_iter_end(&conn_iter);
+
+ /* Don't return stale data (e.g. pending async disable). */
+ if (uses_atomic)
+ return NULL;
+
+ return encoder->crtc;
+}
+
+int drm_mode_getencoder(struct drm_device *dev, void *data,
+ struct drm_file *file_priv)
+{
+ struct drm_mode_get_encoder *enc_resp = data;
+ struct drm_encoder *encoder;
+ struct drm_crtc *crtc;
+
+ if (!drm_core_check_feature(dev, DRIVER_MODESET))
+ return -EINVAL;
+
+ encoder = drm_encoder_find(dev, file_priv, enc_resp->encoder_id);
+ if (!encoder)
+ return -ENOENT;
+
+ drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
+ crtc = drm_encoder_get_crtc(encoder);
+ if (crtc && drm_lease_held(file_priv, crtc->base.id))
+ enc_resp->crtc_id = crtc->base.id;
+ else
+ enc_resp->crtc_id = 0;
+ drm_modeset_unlock(&dev->mode_config.connection_mutex);
+
+ enc_resp->encoder_type = encoder->encoder_type;
+ enc_resp->encoder_id = encoder->base.id;
+ enc_resp->possible_crtcs = drm_lease_filter_crtcs(file_priv,
+ encoder->possible_crtcs);
+ enc_resp->possible_clones = encoder->possible_clones;
+
+ return 0;
+}