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Release 4.14 drivers/gpu/drm/drm_encoder.c

Directory: drivers/gpu/drm
/*
 * 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; }

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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); } }

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/** * 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; 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; }

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Daniel Vetter19599.49%266.67%
Thierry Reding10.51%133.33%
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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)); }

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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; }

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Daniel Vetter10597.22%266.67%
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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, 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) 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 = encoder->possible_crtcs; enc_resp->possible_clones = encoder->possible_clones; return 0; }

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Thierry Reding40.53%222.22%
Total755100.00%9100.00%
Directory: drivers/gpu/drm
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