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

#ifndef __LINUX_DRM_SIMPLE_KMS_HELPER_H
#define __LINUX_DRM_SIMPLE_KMS_HELPER_H

#include <drm/drm_crtc.h>
#include <drm/drm_encoder.h>
#include <drm/drm_plane.h>

struct drm_simple_display_pipe;

/**
 * struct drm_simple_display_pipe_funcs - helper operations for a simple
 *                                        display pipeline
 */
struct drm_simple_display_pipe_funcs {
        /**
         * @mode_valid:
         *
         * This callback is used to check if a specific mode is valid in the
         * crtc used in this simple display pipe. This should be implemented
         * if the display pipe has some sort of restriction in the modes
         * it can display. For example, a given display pipe may be responsible
         * to set a clock value. If the clock can not produce all the values
         * for the available modes then this callback can be used to restrict
         * the number of modes to only the ones that can be displayed. Another
         * reason can be bandwidth mitigation: the memory port on the display
         * controller can have bandwidth limitations not allowing pixel data
         * to be fetched at any rate.
         *
         * This hook is used by the probe helpers to filter the mode list in
         * drm_helper_probe_single_connector_modes(), and it is used by the
         * atomic helpers to validate modes supplied by userspace in
         * drm_atomic_helper_check_modeset().
         *
         * This function is optional.
         *
         * NOTE:
         *
         * Since this function is both called from the check phase of an atomic
         * commit, and the mode validation in the probe paths it is not allowed
         * to look at anything else but the passed-in mode, and validate it
         * against configuration-invariant hardware constraints.
         *
         * RETURNS:
         *
         * drm_mode_status Enum
         */
        enum drm_mode_status (*mode_valid)(struct drm_simple_display_pipe *pipe,
                                           const struct drm_display_mode *mode);

        /**
         * @enable:
         *
         * This function should be used to enable the pipeline.
         * It is called when the underlying crtc is enabled.
         * This hook is optional.
         */
        void (*enable)(struct drm_simple_display_pipe *pipe,
                       struct drm_crtc_state *crtc_state,
                       struct drm_plane_state *plane_state);
        /**
         * @disable:
         *
         * This function should be used to disable the pipeline.
         * It is called when the underlying crtc is disabled.
         * This hook is optional.
         */
        void (*disable)(struct drm_simple_display_pipe *pipe);

        /**
         * @check:
         *
         * This function is called in the check phase of an atomic update,
         * specifically when the underlying plane is checked.
         * The simple display pipeline helpers already check that the plane is
         * not scaled, fills the entire visible area and is always enabled
         * when the crtc is also enabled.
         * This hook is optional.
         *
         * RETURNS:
         *
         * 0 on success, -EINVAL if the state or the transition can't be
         * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
         * attempt to obtain another state object ran into a &drm_modeset_lock
         * deadlock.
         */
        int (*check)(struct drm_simple_display_pipe *pipe,
                     struct drm_plane_state *plane_state,
                     struct drm_crtc_state *crtc_state);
        /**
         * @update:
         *
         * This function is called when the underlying plane state is updated.
         * This hook is optional.
         *
         * This is the function drivers should submit the
         * &drm_pending_vblank_event from. Using either
         * drm_crtc_arm_vblank_event(), when the driver supports vblank
         * interrupt handling, or drm_crtc_send_vblank_event() for more
         * complex case. In case the hardware lacks vblank support entirely,
         * drivers can set &struct drm_crtc_state.no_vblank in
         * &struct drm_simple_display_pipe_funcs.check and let DRM's
         * atomic helper fake a vblank event.
         */
        void (*update)(struct drm_simple_display_pipe *pipe,
                       struct drm_plane_state *old_plane_state);

        /**
         * @prepare_fb:
         *
         * Optional, called by &drm_plane_helper_funcs.prepare_fb.  Please read
         * the documentation for the &drm_plane_helper_funcs.prepare_fb hook for
         * more details.
         *
         * For GEM drivers who neither have a @prepare_fb nor @cleanup_fb hook
         * set drm_gem_simple_display_pipe_prepare_fb() is called automatically
         * to implement this. Other drivers which need additional plane
         * processing can call drm_gem_simple_display_pipe_prepare_fb() from
         * their @prepare_fb hook.
         */
        int (*prepare_fb)(struct drm_simple_display_pipe *pipe,
                          struct drm_plane_state *plane_state);

        /**
         * @cleanup_fb:
         *
         * Optional, called by &drm_plane_helper_funcs.cleanup_fb.  Please read
         * the documentation for the &drm_plane_helper_funcs.cleanup_fb hook for
         * more details.
         */
        void (*cleanup_fb)(struct drm_simple_display_pipe *pipe,
                           struct drm_plane_state *plane_state);

        /**
         * @enable_vblank:
         *
         * Optional, called by &drm_crtc_funcs.enable_vblank. Please read
         * the documentation for the &drm_crtc_funcs.enable_vblank hook for
         * more details.
         */
        int (*enable_vblank)(struct drm_simple_display_pipe *pipe);

        /**
         * @disable_vblank:
         *
         * Optional, called by &drm_crtc_funcs.disable_vblank. Please read
         * the documentation for the &drm_crtc_funcs.disable_vblank hook for
         * more details.
         */
        void (*disable_vblank)(struct drm_simple_display_pipe *pipe);

        /**
         * @reset_crtc:
         *
         * Optional, called by &drm_crtc_funcs.reset. Please read the
         * documentation for the &drm_crtc_funcs.reset hook for more details.
         */
        void (*reset_crtc)(struct drm_simple_display_pipe *pipe);

        /**
         * @duplicate_crtc_state:
         *
         * Optional, called by &drm_crtc_funcs.atomic_duplicate_state. Please
         * read the documentation for the &drm_crtc_funcs.atomic_duplicate_state
         * hook for more details.
         */
        struct drm_crtc_state * (*duplicate_crtc_state)(struct drm_simple_display_pipe *pipe);

        /**
         * @destroy_crtc_state:
         *
         * Optional, called by &drm_crtc_funcs.atomic_destroy_state. Please
         * read the documentation for the &drm_crtc_funcs.atomic_destroy_state
         * hook for more details.
         */
        void (*destroy_crtc_state)(struct drm_simple_display_pipe *pipe,
                                   struct drm_crtc_state *crtc_state);

        /**
         * @reset_plane:
         *
         * Optional, called by &drm_plane_funcs.reset. Please read the
         * documentation for the &drm_plane_funcs.reset hook for more details.
         */
        void (*reset_plane)(struct drm_simple_display_pipe *pipe);

        /**
         * @duplicate_plane_state:
         *
         * Optional, called by &drm_plane_funcs.atomic_duplicate_state.  Please
         * read the documentation for the &drm_plane_funcs.atomic_duplicate_state
         * hook for more details.
         */
        struct drm_plane_state * (*duplicate_plane_state)(struct drm_simple_display_pipe *pipe);

        /**
         * @destroy_plane_state:
         *
         * Optional, called by &drm_plane_funcs.atomic_destroy_state.  Please
         * read the documentation for the &drm_plane_funcs.atomic_destroy_state
         * hook for more details.
         */
        void (*destroy_plane_state)(struct drm_simple_display_pipe *pipe,
                                    struct drm_plane_state *plane_state);
};

/**
 * struct drm_simple_display_pipe - simple display pipeline
 * @crtc: CRTC control structure
 * @plane: Plane control structure
 * @encoder: Encoder control structure
 * @connector: Connector control structure
 * @funcs: Pipeline control functions (optional)
 *
 * Simple display pipeline with plane, crtc and encoder collapsed into one
 * entity. It should be initialized by calling drm_simple_display_pipe_init().
 */
struct drm_simple_display_pipe {
        struct drm_crtc crtc;
        struct drm_plane plane;
        struct drm_encoder encoder;
        struct drm_connector *connector;

        const struct drm_simple_display_pipe_funcs *funcs;
};

int drm_simple_display_pipe_attach_bridge(struct drm_simple_display_pipe *pipe,
                                          struct drm_bridge *bridge);

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);

int drm_simple_encoder_init(struct drm_device *dev,
                            struct drm_encoder *encoder,
                            int encoder_type);

void *__drmm_simple_encoder_alloc(struct drm_device *dev, size_t size,
                                  size_t offset, int encoder_type);

/**
 * drmm_simple_encoder_alloc - Allocate and initialize an encoder with basic
 *                             functionality.
 * @dev: drm device
 * @type: the type of the struct which contains struct &drm_encoder
 * @member: the name of the &drm_encoder within @type.
 * @encoder_type: user visible type of the encoder
 *
 * Allocates and initializes an encoder that has no further functionality.
 * Settings for possible CRTC and clones are left to their initial values.
 * Cleanup is automatically handled through registering drm_encoder_cleanup()
 * with drmm_add_action().
 *
 * Returns:
 * Pointer to new encoder, or ERR_PTR on failure.
 */
#define drmm_simple_encoder_alloc(dev, type, member, encoder_type) \
        ((type *)__drmm_simple_encoder_alloc(dev, sizeof(type), \
                                             offsetof(type, member), \
                                             encoder_type))

#endif /* __LINUX_DRM_SIMPLE_KMS_HELPER_H */