xref: /dragonfly/sys/dev/drm/include/drm/drm_fb_helper.h (revision 789731325bde747251c28a37e0a00ed4efb88c46)

/*
 * Copyright (c) 2006-2009 Red Hat Inc.
 * Copyright (c) 2006-2008 Intel Corporation
 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
 *
 * DRM framebuffer helper functions
 *
 * 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.
 *
 * Authors:
 *      Dave Airlie <airlied@linux.ie>
 *      Jesse Barnes <jesse.barnes@intel.com>
 */
#ifndef DRM_FB_HELPER_H
#define DRM_FB_HELPER_H

struct drm_fb_helper;

#include <drm/drm_crtc.h>
#include <linux/kgdb.h>

enum mode_set_atomic {
          LEAVE_ATOMIC_MODE_SET,
          ENTER_ATOMIC_MODE_SET,
};

struct drm_fb_offset {
          int x, y;
};

struct drm_fb_helper_crtc {
          struct drm_mode_set mode_set;
          struct drm_display_mode *desired_mode;
          int x, y;
};

/**
 * struct drm_fb_helper_surface_size - describes fbdev size and scanout surface size
 * @fb_width: fbdev width
 * @fb_height: fbdev height
 * @surface_width: scanout buffer width
 * @surface_height: scanout buffer height
 * @surface_bpp: scanout buffer bpp
 * @surface_depth: scanout buffer depth
 *
 * Note that the scanout surface width/height may be larger than the fbdev
 * width/height.  In case of multiple displays, the scanout surface is sized
 * according to the largest width/height (so it is large enough for all CRTCs
 * to scanout).  But the fbdev width/height is sized to the minimum width/
 * height of all the displays.  This ensures that fbcon fits on the smallest
 * of the attached displays.
 *
 * So what is passed to drm_fb_helper_fill_var() should be fb_width/fb_height,
 * rather than the surface size.
 */
struct drm_fb_helper_surface_size {
          u32 fb_width;
          u32 fb_height;
          u32 surface_width;
          u32 surface_height;
          u32 surface_bpp;
          u32 surface_depth;
};

/**
 * struct drm_fb_helper_funcs - driver callbacks for the fbdev emulation library
 *
 * Driver callbacks used by the fbdev emulation helper library.
 */
struct drm_fb_helper_funcs {
          /**
           * @fb_probe:
           *
           * Driver callback to allocate and initialize the fbdev info structure.
           * Furthermore it also needs to allocate the DRM framebuffer used to
           * back the fbdev.
           *
           * This callback is mandatory.
           *
           * RETURNS:
           *
           * The driver should return 0 on success and a negative error code on
           * failure.
           */
          int (*fb_probe)(struct drm_fb_helper *helper,
                              struct drm_fb_helper_surface_size *sizes);

          /**
           * @initial_config:
           *
           * Driver callback to setup an initial fbdev display configuration.
           * Drivers can use this callback to tell the fbdev emulation what the
           * preferred initial configuration is. This is useful to implement
           * smooth booting where the fbdev (and subsequently all userspace) never
           * changes the mode, but always inherits the existing configuration.
           *
           * This callback is optional.
           *
           * RETURNS:
           *
           * The driver should return true if a suitable initial configuration has
           * been filled out and false when the fbdev helper should fall back to
           * the default probing logic.
           */
          bool (*initial_config)(struct drm_fb_helper *fb_helper,
                                     struct drm_fb_helper_crtc **crtcs,
                                     struct drm_display_mode **modes,
                                     struct drm_fb_offset *offsets,
                                     bool *enabled, int width, int height);
};

struct drm_fb_helper_connector {
          struct drm_connector *connector;
};

/**
 * struct drm_fb_helper - main structure to emulate fbdev on top of KMS
 * @fb: Scanout framebuffer object
 * @dev: DRM device
 * @crtc_count: number of possible CRTCs
 * @crtc_info: per-CRTC helper state (mode, x/y offset, etc)
 * @connector_count: number of connected connectors
 * @connector_info_alloc_count: size of connector_info
 * @funcs: driver callbacks for fb helper
 * @fbdev: emulated fbdev device info struct
 * @pseudo_palette: fake palette of 16 colors
 * @dirty_clip: clip rectangle used with deferred_io to accumulate damage to
 *              the screen buffer
 * @dirty_lock: spinlock protecting @dirty_clip
 * @dirty_work: worker used to flush the framebuffer
 * @resume_work: worker used during resume if the console lock is already taken
 *
 * This is the main structure used by the fbdev helpers. Drivers supporting
 * fbdev emulation should embedded this into their overall driver structure.
 * Drivers must also fill out a &struct drm_fb_helper_funcs with a few
 * operations.
 */
struct drm_fb_helper {
          struct drm_framebuffer *fb;
          struct drm_device *dev;
          int crtc_count;
          struct drm_fb_helper_crtc *crtc_info;
          int connector_count;
          int connector_info_alloc_count;
          /**
           * @connector_info:
           *
           * Array of per-connector information. Do not iterate directly, but use
           * drm_fb_helper_for_each_connector.
           */
          struct drm_fb_helper_connector **connector_info;
          const struct drm_fb_helper_funcs *funcs;
          struct fb_info *fbdev;
          u32 pseudo_palette[17];
          struct drm_clip_rect dirty_clip;
          spinlock_t dirty_lock;
          struct work_struct dirty_work;
          struct work_struct resume_work;

          /**
           * @lock:
           *
           * Top-level FBDEV helper lock. This protects all internal data
           * structures and lists, such as @connector_info and @crtc_info.
           *
           * FIXME: fbdev emulation locking is a mess and long term we want to
           * protect all helper internal state with this lock as well as reduce
           * core KMS locking as much as possible.
           */
          struct lock lock;

          /**
           * @kernel_fb_list:
           *
           * Entry on the global kernel_fb_helper_list, used for kgdb entry/exit.
           */
          struct list_head kernel_fb_list;

          /**
           * @delayed_hotplug:
           *
           * A hotplug was received while fbdev wasn't in control of the DRM
           * device, i.e. another KMS master was active. The output configuration
           * needs to be reprobe when fbdev is in control again.
           */
          bool delayed_hotplug;

          /**
           * @deferred_setup:
           *
           * If no outputs are connected (disconnected or unknown) the FB helper
           * code will defer setup until at least one of the outputs shows up.
           * This field keeps track of the status so that setup can be retried
           * at every hotplug event until it succeeds eventually.
           *
           * Protected by @lock.
           */
          bool deferred_setup;

          /**
           * @preferred_bpp:
           *
           * Temporary storage for the driver's preferred BPP setting passed to
           * FB helper initialization. This needs to be tracked so that deferred
           * FB helper setup can pass this on.
           *
           * See also: @deferred_setup
           */
          int preferred_bpp;
};

/**
 * define DRM_FB_HELPER_DEFAULT_OPS - helper define for drm drivers
 *
 * Helper define to register default implementations of drm_fb_helper
 * functions. To be used in struct fb_ops of drm drivers.
 */
#define DRM_FB_HELPER_DEFAULT_OPS \
          .fb_check_var       = drm_fb_helper_check_var, \
          .fb_set_par         = drm_fb_helper_set_par, \
          .fb_setcmap         = drm_fb_helper_setcmap, \
          .fb_blank = drm_fb_helper_blank, \
          .fb_pan_display     = drm_fb_helper_pan_display, \
          .fb_debug_enter = drm_fb_helper_debug_enter, \
          .fb_debug_leave = drm_fb_helper_debug_leave, \
          .fb_ioctl = drm_fb_helper_ioctl

#ifdef CONFIG_DRM_FBDEV_EMULATION
void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
                                 const struct drm_fb_helper_funcs *funcs);
int drm_fb_helper_init(struct drm_device *dev,
                           struct drm_fb_helper *helper, int max_conn);
void drm_fb_helper_fini(struct drm_fb_helper *helper);
int drm_fb_helper_blank(int blank, struct fb_info *info);
int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
                                    struct fb_info *info);
int drm_fb_helper_set_par(struct fb_info *info);
int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
                                  struct fb_info *info);

int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);

struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper);
void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper);
void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
                                  uint32_t fb_width, uint32_t fb_height);
void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
                                  uint32_t depth);

void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper);

void drm_fb_helper_deferred_io(struct fb_info *info,
                                     struct list_head *pagelist);

ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
                                     size_t count, loff_t *ppos);
ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
                                        size_t count, loff_t *ppos);

void drm_fb_helper_sys_fillrect(struct fb_info *info,
                                        const struct fb_fillrect *rect);
void drm_fb_helper_sys_copyarea(struct fb_info *info,
                                        const struct fb_copyarea *area);
void drm_fb_helper_sys_imageblit(struct fb_info *info,
                                         const struct fb_image *image);

void drm_fb_helper_cfb_fillrect(struct fb_info *info,
                                        const struct fb_fillrect *rect);
void drm_fb_helper_cfb_copyarea(struct fb_info *info,
                                        const struct fb_copyarea *area);
void drm_fb_helper_cfb_imageblit(struct fb_info *info,
                                         const struct fb_image *image);

void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend);
void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
                                                  bool suspend);

int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);

int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
                              unsigned long arg);

int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel);
int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper);
int drm_fb_helper_debug_enter(struct fb_info *info);
int drm_fb_helper_debug_leave(struct fb_info *info);
struct drm_display_mode *
drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
                              int width, int height);
struct drm_display_mode *
drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn);

int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector);
int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
                                               struct drm_connector *connector);
void drm_fb_helper_output_poll_changed(struct drm_device *dev);
#else
static inline void drm_fb_helper_prepare(struct drm_device *dev,
                                                  struct drm_fb_helper *helper,
                                                  const struct drm_fb_helper_funcs *funcs)
{
}

static inline int drm_fb_helper_init(struct drm_device *dev,
                           struct drm_fb_helper *helper,
                           int max_conn)
{
          return 0;
}

static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
{
}

static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
{
          return 0;
}

static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
                                                      struct fb_info *info)
{
          return 0;
}

static inline int drm_fb_helper_set_par(struct fb_info *info)
{
          return 0;
}

static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
                                                    struct fb_info *info)
{
          return 0;
}

static inline int
drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
{
          return 0;
}

static inline struct fb_info *
drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
{
          return NULL;
}

static inline void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
{
}

static inline void drm_fb_helper_fill_var(struct fb_info *info,
                                                    struct drm_fb_helper *fb_helper,
                                                    uint32_t fb_width, uint32_t fb_height)
{
}

static inline void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
                                                    uint32_t depth)
{
}

static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
                                                  struct fb_info *info)
{
          return 0;
}

static inline int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
                                              unsigned long arg)
{
          return 0;
}

static inline void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper)
{
}

static inline void drm_fb_helper_deferred_io(struct fb_info *info,
                                                       struct list_head *pagelist)
{
}

static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
                                                       char __user *buf, size_t count,
                                                       loff_t *ppos)
{
          return -ENODEV;
}

static inline ssize_t drm_fb_helper_sys_write(struct fb_info *info,
                                                        const char __user *buf,
                                                        size_t count, loff_t *ppos)
{
          return -ENODEV;
}

static inline void drm_fb_helper_sys_fillrect(struct fb_info *info,
                                                        const struct fb_fillrect *rect)
{
}

static inline void drm_fb_helper_sys_copyarea(struct fb_info *info,
                                                        const struct fb_copyarea *area)
{
}

static inline void drm_fb_helper_sys_imageblit(struct fb_info *info,
                                                         const struct fb_image *image)
{
}

static inline void drm_fb_helper_cfb_fillrect(struct fb_info *info,
                                                        const struct fb_fillrect *rect)
{
}

static inline void drm_fb_helper_cfb_copyarea(struct fb_info *info,
                                                        const struct fb_copyarea *area)
{
}

static inline void drm_fb_helper_cfb_imageblit(struct fb_info *info,
                                                         const struct fb_image *image)
{
}

static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
                                                       bool suspend)
{
}

static inline void
drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, bool suspend)
{
}

static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
{
          return 0;
}

static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper,
                                                         int bpp_sel)
{
          return 0;
}

static inline int
drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
{
          return 0;
}

static inline int drm_fb_helper_debug_enter(struct fb_info *info)
{
          return 0;
}

static inline int drm_fb_helper_debug_leave(struct fb_info *info)
{
          return 0;
}

static inline struct drm_display_mode *
drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
                           int width, int height)
{
          return NULL;
}

static inline struct drm_display_mode *
drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
                          int width, int height)
{
          return NULL;
}

static inline int
drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
                                        struct drm_connector *connector)
{
          return 0;
}

static inline int
drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
                                           struct drm_connector *connector)
{
          return 0;
}


static inline void drm_fb_helper_output_poll_changed(struct drm_device *dev)
{
}

#endif

static inline int
drm_fb_helper_remove_conflicting_framebuffers(struct apertures_struct *a,
                                                        const char *name, bool primary)
{
#if IS_ENABLED(CONFIG_FB)
          return remove_conflicting_framebuffers(a, name, primary);
#else
          return 0;
#endif
}

#endif