drm_simple_kms_helper.c | Explore in Territory

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2016 Noralf Trønnes
 */

#include <linux/module.h>
#include <linux/slab.h>

#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_bridge.h>
#include <drm/drm_drv.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_managed.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_simple_kms_helper.h>

/**
 * DOC: overview
 *
 * This helper library provides helpers for drivers for simple display
 * hardware.
 *
 * drm_simple_display_pipe_init() initializes a simple display pipeline
 * which has only one full-screen scanout buffer feeding one output. The
 * pipeline is represented by &struct drm_simple_display_pipe and binds
 * together &drm_plane, &drm_crtc and &drm_encoder structures into one fixed
 * entity. Some flexibility for code reuse is provided through a separately
 * allocated &drm_connector object and supporting optional &drm_bridge
 * encoder drivers.
 *
 * Many drivers require only a very simple encoder that fulfills the minimum
 * requirements of the display pipeline and does not add additional
 * functionality. The function drm_simple_encoder_init() provides an
 * implementation of such an encoder.
 */

static const struct drm_encoder_funcs drm_simple_encoder_funcs_cleanup = …;

/**
 * drm_simple_encoder_init - Initialize a preallocated encoder with
 *                           basic functionality.
 * @dev: drm device
 * @encoder: the encoder to initialize
 * @encoder_type: user visible type of the encoder
 *
 * Initialises a preallocated encoder that has no further functionality.
 * Settings for possible CRTC and clones are left to their initial values.
 * The encoder will be cleaned up automatically as part of the mode-setting
 * cleanup.
 *
 * The caller of drm_simple_encoder_init() is responsible for freeing
 * the encoder's memory after the encoder has been cleaned up. At the
 * moment this only works reliably if the encoder data structure is
 * stored in the device structure. Free the encoder's memory as part of
 * the device release function.
 *
 * Note: consider using drmm_simple_encoder_alloc() instead of
 * drm_simple_encoder_init() to let the DRM managed resource infrastructure
 * take care of cleanup and deallocation.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_simple_encoder_init(struct drm_device *dev,
			    struct drm_encoder *encoder,
			    int encoder_type)
{ … }
EXPORT_SYMBOL(…);

void *__drmm_simple_encoder_alloc(struct drm_device *dev, size_t size,
				  size_t offset, int encoder_type)
{ … }
EXPORT_SYMBOL(…);

static enum drm_mode_status
drm_simple_kms_crtc_mode_valid(struct drm_crtc *crtc,
			       const struct drm_display_mode *mode)
{ … }

static int drm_simple_kms_crtc_check(struct drm_crtc *crtc,
				     struct drm_atomic_state *state)
{ … }

static void drm_simple_kms_crtc_enable(struct drm_crtc *crtc,
				       struct drm_atomic_state *state)
{ … }

static void drm_simple_kms_crtc_disable(struct drm_crtc *crtc,
					struct drm_atomic_state *state)
{ … }

static const struct drm_crtc_helper_funcs drm_simple_kms_crtc_helper_funcs = …;

static void drm_simple_kms_crtc_reset(struct drm_crtc *crtc)
{ … }

static struct drm_crtc_state *drm_simple_kms_crtc_duplicate_state(struct drm_crtc *crtc)
{ … }

static void drm_simple_kms_crtc_destroy_state(struct drm_crtc *crtc, struct drm_crtc_state *state)
{ … }

static int drm_simple_kms_crtc_enable_vblank(struct drm_crtc *crtc)
{ … }

static void drm_simple_kms_crtc_disable_vblank(struct drm_crtc *crtc)
{ … }

static const struct drm_crtc_funcs drm_simple_kms_crtc_funcs = …;

static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane,
					struct drm_atomic_state *state)
{ … }

static void drm_simple_kms_plane_atomic_update(struct drm_plane *plane,
					struct drm_atomic_state *state)
{ … }

static int drm_simple_kms_plane_prepare_fb(struct drm_plane *plane,
					   struct drm_plane_state *state)
{ … }

static void drm_simple_kms_plane_cleanup_fb(struct drm_plane *plane,
					    struct drm_plane_state *state)
{ … }

static int drm_simple_kms_plane_begin_fb_access(struct drm_plane *plane,
						struct drm_plane_state *new_plane_state)
{ … }

static void drm_simple_kms_plane_end_fb_access(struct drm_plane *plane,
					       struct drm_plane_state *new_plane_state)
{ … }

static bool drm_simple_kms_format_mod_supported(struct drm_plane *plane,
						uint32_t format,
						uint64_t modifier)
{ … }

static const struct drm_plane_helper_funcs drm_simple_kms_plane_helper_funcs = …;

static void drm_simple_kms_plane_reset(struct drm_plane *plane)
{ … }

static struct drm_plane_state *drm_simple_kms_plane_duplicate_state(struct drm_plane *plane)
{ … }

static void drm_simple_kms_plane_destroy_state(struct drm_plane *plane,
					       struct drm_plane_state *state)
{ … }

static const struct drm_plane_funcs drm_simple_kms_plane_funcs = …;

/**
 * drm_simple_display_pipe_attach_bridge - Attach a bridge to the display pipe
 * @pipe: simple display pipe object
 * @bridge: bridge to attach
 *
 * Makes it possible to still use the drm_simple_display_pipe helpers when
 * a DRM bridge has to be used.
 *
 * Note that you probably want to initialize the pipe by passing a NULL
 * connector to drm_simple_display_pipe_init().
 *
 * Returns:
 * Zero on success, negative error code on failure.
 */
int drm_simple_display_pipe_attach_bridge(struct drm_simple_display_pipe *pipe,
					  struct drm_bridge *bridge)
{ … }
EXPORT_SYMBOL(…);

/**
 * drm_simple_display_pipe_init - Initialize a simple display pipeline
 * @dev: DRM device
 * @pipe: simple display pipe object to initialize
 * @funcs: callbacks for the display pipe (optional)
 * @formats: array of supported formats (DRM_FORMAT\_\*)
 * @format_count: number of elements in @formats
 * @format_modifiers: array of formats modifiers
 * @connector: connector to attach and register (optional)
 *
 * Sets up a display pipeline which consist of a really simple
 * plane-crtc-encoder pipe.
 *
 * If a connector is supplied, the pipe will be coupled with the provided
 * connector. You may supply a NULL connector when using drm bridges, that
 * handle connectors themselves (see drm_simple_display_pipe_attach_bridge()).
 *
 * Teardown of a simple display pipe is all handled automatically by the drm
 * core through calling drm_mode_config_cleanup(). Drivers afterwards need to
 * release the memory for the structure themselves.
 *
 * Returns:
 * Zero on success, negative error code on failure.
 */
int drm_simple_display_pipe_init(struct drm_device *dev,
			struct drm_simple_display_pipe *pipe,
			const struct drm_simple_display_pipe_funcs *funcs,
			const uint32_t *formats, unsigned int format_count,
			const uint64_t *format_modifiers,
			struct drm_connector *connector)
{ … }
EXPORT_SYMBOL(…);

MODULE_DESCRIPTION(…) …;
MODULE_LICENSE(…) …;
linux/drivers/gpu/drm/drm_simple_kms_helper.c
