2 * Copyright (c) 2006-2009 Red Hat Inc.
3 * Copyright (c) 2006-2008 Intel Corporation
4 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
6 * DRM framebuffer helper functions
8 * Permission to use, copy, modify, distribute, and sell this software and its
9 * documentation for any purpose is hereby granted without fee, provided that
10 * the above copyright notice appear in all copies and that both that copyright
11 * notice and this permission notice appear in supporting documentation, and
12 * that the name of the copyright holders not be used in advertising or
13 * publicity pertaining to distribution of the software without specific,
14 * written prior permission. The copyright holders make no representations
15 * about the suitability of this software for any purpose. It is provided "as
16 * is" without express or implied warranty.
18 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
19 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
20 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
21 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
22 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
23 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
27 * Dave Airlie <airlied@linux.ie>
28 * Jesse Barnes <jesse.barnes@intel.com>
30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
32 #include <linux/kernel.h>
33 #include <linux/sysrq.h>
34 #include <linux/slab.h>
36 #include <linux/module.h>
38 #include <drm/drm_crtc.h>
39 #include <drm/drm_fb_helper.h>
40 #include <drm/drm_crtc_helper.h>
41 #include <drm/drm_atomic.h>
42 #include <drm/drm_atomic_helper.h>
44 static bool drm_fbdev_emulation
= true;
45 module_param_named(fbdev_emulation
, drm_fbdev_emulation
, bool, 0600);
46 MODULE_PARM_DESC(fbdev_emulation
,
47 "Enable legacy fbdev emulation [default=true]");
49 static LIST_HEAD(kernel_fb_helper_list
);
54 * The fb helper functions are useful to provide an fbdev on top of a drm kernel
55 * mode setting driver. They can be used mostly independently from the crtc
56 * helper functions used by many drivers to implement the kernel mode setting
59 * Initialization is done as a four-step process with drm_fb_helper_prepare(),
60 * drm_fb_helper_init(), drm_fb_helper_single_add_all_connectors() and
61 * drm_fb_helper_initial_config(). Drivers with fancier requirements than the
62 * default behaviour can override the third step with their own code.
63 * Teardown is done with drm_fb_helper_fini().
65 * At runtime drivers should restore the fbdev console by calling
66 * drm_fb_helper_restore_fbdev_mode_unlocked() from their ->lastclose callback.
67 * They should also notify the fb helper code from updates to the output
68 * configuration by calling drm_fb_helper_hotplug_event(). For easier
69 * integration with the output polling code in drm_crtc_helper.c the modeset
70 * code provides a ->output_poll_changed callback.
72 * All other functions exported by the fb helper library can be used to
73 * implement the fbdev driver interface by the driver.
75 * It is possible, though perhaps somewhat tricky, to implement race-free
76 * hotplug detection using the fbdev helpers. The drm_fb_helper_prepare()
77 * helper must be called first to initialize the minimum required to make
78 * hotplug detection work. Drivers also need to make sure to properly set up
79 * the dev->mode_config.funcs member. After calling drm_kms_helper_poll_init()
80 * it is safe to enable interrupts and start processing hotplug events. At the
81 * same time, drivers should initialize all modeset objects such as CRTCs,
82 * encoders and connectors. To finish up the fbdev helper initialization, the
83 * drm_fb_helper_init() function is called. To probe for all attached displays
84 * and set up an initial configuration using the detected hardware, drivers
85 * should call drm_fb_helper_single_add_all_connectors() followed by
86 * drm_fb_helper_initial_config().
90 * drm_fb_helper_single_add_all_connectors() - add all connectors to fbdev
92 * @fb_helper: fbdev initialized with drm_fb_helper_init
94 * This functions adds all the available connectors for use with the given
95 * fb_helper. This is a separate step to allow drivers to freely assign
96 * connectors to the fbdev, e.g. if some are reserved for special purposes or
97 * not adequate to be used for the fbcon.
99 * This function is protected against concurrent connector hotadds/removals
100 * using drm_fb_helper_add_one_connector() and
101 * drm_fb_helper_remove_one_connector().
103 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper
*fb_helper
)
105 struct drm_device
*dev
= fb_helper
->dev
;
106 struct drm_connector
*connector
;
109 if (!drm_fbdev_emulation
)
112 mutex_lock(&dev
->mode_config
.mutex
);
113 drm_for_each_connector(connector
, dev
) {
114 ret
= drm_fb_helper_add_one_connector(fb_helper
, connector
);
119 mutex_unlock(&dev
->mode_config
.mutex
);
122 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
123 kfree(fb_helper
->connector_info
[i
]);
124 fb_helper
->connector_info
[i
] = NULL
;
126 fb_helper
->connector_count
= 0;
127 mutex_unlock(&dev
->mode_config
.mutex
);
131 EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors
);
133 int drm_fb_helper_add_one_connector(struct drm_fb_helper
*fb_helper
, struct drm_connector
*connector
)
135 struct drm_fb_helper_connector
**temp
;
136 struct drm_fb_helper_connector
*fb_helper_connector
;
138 if (!drm_fbdev_emulation
)
141 WARN_ON(!mutex_is_locked(&fb_helper
->dev
->mode_config
.mutex
));
142 if (fb_helper
->connector_count
+ 1 > fb_helper
->connector_info_alloc_count
) {
143 temp
= krealloc(fb_helper
->connector_info
, sizeof(struct drm_fb_helper_connector
*) * (fb_helper
->connector_count
+ 1), GFP_KERNEL
);
147 fb_helper
->connector_info_alloc_count
= fb_helper
->connector_count
+ 1;
148 fb_helper
->connector_info
= temp
;
152 fb_helper_connector
= kzalloc(sizeof(struct drm_fb_helper_connector
), GFP_KERNEL
);
153 if (!fb_helper_connector
)
156 fb_helper_connector
->connector
= connector
;
157 fb_helper
->connector_info
[fb_helper
->connector_count
++] = fb_helper_connector
;
160 EXPORT_SYMBOL(drm_fb_helper_add_one_connector
);
162 static void remove_from_modeset(struct drm_mode_set
*set
,
163 struct drm_connector
*connector
)
167 for (i
= 0; i
< set
->num_connectors
; i
++) {
168 if (set
->connectors
[i
] == connector
)
172 if (i
== set
->num_connectors
)
175 for (j
= i
+ 1; j
< set
->num_connectors
; j
++) {
176 set
->connectors
[j
- 1] = set
->connectors
[j
];
178 set
->num_connectors
--;
181 * TODO maybe need to makes sure we set it back to !=NULL somewhere?
183 if (set
->num_connectors
== 0) {
185 drm_mode_destroy(connector
->dev
, set
->mode
);
190 int drm_fb_helper_remove_one_connector(struct drm_fb_helper
*fb_helper
,
191 struct drm_connector
*connector
)
193 struct drm_fb_helper_connector
*fb_helper_connector
;
196 if (!drm_fbdev_emulation
)
199 WARN_ON(!mutex_is_locked(&fb_helper
->dev
->mode_config
.mutex
));
201 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
202 if (fb_helper
->connector_info
[i
]->connector
== connector
)
206 if (i
== fb_helper
->connector_count
)
208 fb_helper_connector
= fb_helper
->connector_info
[i
];
210 for (j
= i
+ 1; j
< fb_helper
->connector_count
; j
++) {
211 fb_helper
->connector_info
[j
- 1] = fb_helper
->connector_info
[j
];
213 fb_helper
->connector_count
--;
214 kfree(fb_helper_connector
);
216 /* also cleanup dangling references to the connector: */
217 for (i
= 0; i
< fb_helper
->crtc_count
; i
++)
218 remove_from_modeset(&fb_helper
->crtc_info
[i
].mode_set
, connector
);
222 EXPORT_SYMBOL(drm_fb_helper_remove_one_connector
);
224 static void drm_fb_helper_save_lut_atomic(struct drm_crtc
*crtc
, struct drm_fb_helper
*helper
)
226 uint16_t *r_base
, *g_base
, *b_base
;
229 if (helper
->funcs
->gamma_get
== NULL
)
232 r_base
= crtc
->gamma_store
;
233 g_base
= r_base
+ crtc
->gamma_size
;
234 b_base
= g_base
+ crtc
->gamma_size
;
236 for (i
= 0; i
< crtc
->gamma_size
; i
++)
237 helper
->funcs
->gamma_get(crtc
, &r_base
[i
], &g_base
[i
], &b_base
[i
], i
);
240 static void drm_fb_helper_restore_lut_atomic(struct drm_crtc
*crtc
)
242 uint16_t *r_base
, *g_base
, *b_base
;
244 if (crtc
->funcs
->gamma_set
== NULL
)
247 r_base
= crtc
->gamma_store
;
248 g_base
= r_base
+ crtc
->gamma_size
;
249 b_base
= g_base
+ crtc
->gamma_size
;
251 crtc
->funcs
->gamma_set(crtc
, r_base
, g_base
, b_base
, 0, crtc
->gamma_size
);
255 * drm_fb_helper_debug_enter - implementation for ->fb_debug_enter
256 * @info: fbdev registered by the helper
258 int drm_fb_helper_debug_enter(struct fb_info
*info
)
260 struct drm_fb_helper
*helper
= info
->par
;
261 const struct drm_crtc_helper_funcs
*funcs
;
264 list_for_each_entry(helper
, &kernel_fb_helper_list
, kernel_fb_list
) {
265 for (i
= 0; i
< helper
->crtc_count
; i
++) {
266 struct drm_mode_set
*mode_set
=
267 &helper
->crtc_info
[i
].mode_set
;
269 if (!mode_set
->crtc
->enabled
)
272 funcs
= mode_set
->crtc
->helper_private
;
273 drm_fb_helper_save_lut_atomic(mode_set
->crtc
, helper
);
274 funcs
->mode_set_base_atomic(mode_set
->crtc
,
278 ENTER_ATOMIC_MODE_SET
);
284 EXPORT_SYMBOL(drm_fb_helper_debug_enter
);
286 /* Find the real fb for a given fb helper CRTC */
287 static struct drm_framebuffer
*drm_mode_config_fb(struct drm_crtc
*crtc
)
289 struct drm_device
*dev
= crtc
->dev
;
292 drm_for_each_crtc(c
, dev
) {
293 if (crtc
->base
.id
== c
->base
.id
)
294 return c
->primary
->fb
;
301 * drm_fb_helper_debug_leave - implementation for ->fb_debug_leave
302 * @info: fbdev registered by the helper
304 int drm_fb_helper_debug_leave(struct fb_info
*info
)
306 struct drm_fb_helper
*helper
= info
->par
;
307 struct drm_crtc
*crtc
;
308 const struct drm_crtc_helper_funcs
*funcs
;
309 struct drm_framebuffer
*fb
;
312 for (i
= 0; i
< helper
->crtc_count
; i
++) {
313 struct drm_mode_set
*mode_set
= &helper
->crtc_info
[i
].mode_set
;
314 crtc
= mode_set
->crtc
;
315 funcs
= crtc
->helper_private
;
316 fb
= drm_mode_config_fb(crtc
);
322 DRM_ERROR("no fb to restore??\n");
326 drm_fb_helper_restore_lut_atomic(mode_set
->crtc
);
327 funcs
->mode_set_base_atomic(mode_set
->crtc
, fb
, crtc
->x
,
328 crtc
->y
, LEAVE_ATOMIC_MODE_SET
);
333 EXPORT_SYMBOL(drm_fb_helper_debug_leave
);
335 static int restore_fbdev_mode_atomic(struct drm_fb_helper
*fb_helper
)
337 struct drm_device
*dev
= fb_helper
->dev
;
338 struct drm_plane
*plane
;
339 struct drm_atomic_state
*state
;
343 state
= drm_atomic_state_alloc(dev
);
347 state
->acquire_ctx
= dev
->mode_config
.acquire_ctx
;
350 drm_for_each_plane(plane
, dev
) {
351 struct drm_plane_state
*plane_state
;
353 plane_state
= drm_atomic_get_plane_state(state
, plane
);
354 if (IS_ERR(plane_state
)) {
355 ret
= PTR_ERR(plane_state
);
359 plane_state
->rotation
= BIT(DRM_ROTATE_0
);
361 plane
->old_fb
= plane
->fb
;
362 plane_mask
|= 1 << drm_plane_index(plane
);
364 /* disable non-primary: */
365 if (plane
->type
== DRM_PLANE_TYPE_PRIMARY
)
368 ret
= __drm_atomic_helper_disable_plane(plane
, plane_state
);
373 for(i
= 0; i
< fb_helper
->crtc_count
; i
++) {
374 struct drm_mode_set
*mode_set
= &fb_helper
->crtc_info
[i
].mode_set
;
376 ret
= __drm_atomic_helper_set_config(mode_set
, state
);
381 ret
= drm_atomic_commit(state
);
384 drm_atomic_clean_old_fb(dev
, plane_mask
, ret
);
390 drm_atomic_state_free(state
);
395 drm_atomic_state_clear(state
);
396 drm_atomic_legacy_backoff(state
);
401 static int restore_fbdev_mode(struct drm_fb_helper
*fb_helper
)
403 struct drm_device
*dev
= fb_helper
->dev
;
404 struct drm_plane
*plane
;
407 drm_warn_on_modeset_not_all_locked(dev
);
409 if (fb_helper
->atomic
)
410 return restore_fbdev_mode_atomic(fb_helper
);
412 drm_for_each_plane(plane
, dev
) {
413 if (plane
->type
!= DRM_PLANE_TYPE_PRIMARY
)
414 drm_plane_force_disable(plane
);
416 if (dev
->mode_config
.rotation_property
) {
417 drm_mode_plane_set_obj_prop(plane
,
418 dev
->mode_config
.rotation_property
,
423 for (i
= 0; i
< fb_helper
->crtc_count
; i
++) {
424 struct drm_mode_set
*mode_set
= &fb_helper
->crtc_info
[i
].mode_set
;
425 struct drm_crtc
*crtc
= mode_set
->crtc
;
428 if (crtc
->funcs
->cursor_set2
) {
429 ret
= crtc
->funcs
->cursor_set2(crtc
, NULL
, 0, 0, 0, 0, 0);
432 } else if (crtc
->funcs
->cursor_set
) {
433 ret
= crtc
->funcs
->cursor_set(crtc
, NULL
, 0, 0, 0);
438 ret
= drm_mode_set_config_internal(mode_set
);
447 * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration
448 * @fb_helper: fbcon to restore
450 * This should be called from driver's drm ->lastclose callback
451 * when implementing an fbcon on top of kms using this helper. This ensures that
452 * the user isn't greeted with a black screen when e.g. X dies.
455 * Zero if everything went ok, negative error code otherwise.
457 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper
*fb_helper
)
459 struct drm_device
*dev
= fb_helper
->dev
;
463 if (!drm_fbdev_emulation
)
466 drm_modeset_lock_all(dev
);
467 ret
= restore_fbdev_mode(fb_helper
);
469 do_delayed
= fb_helper
->delayed_hotplug
;
471 fb_helper
->delayed_hotplug
= false;
472 drm_modeset_unlock_all(dev
);
475 drm_fb_helper_hotplug_event(fb_helper
);
478 EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked
);
480 static bool drm_fb_helper_is_bound(struct drm_fb_helper
*fb_helper
)
482 struct drm_device
*dev
= fb_helper
->dev
;
483 struct drm_crtc
*crtc
;
484 int bound
= 0, crtcs_bound
= 0;
486 /* Sometimes user space wants everything disabled, so don't steal the
487 * display if there's a master. */
488 if (dev
->primary
->master
)
491 drm_for_each_crtc(crtc
, dev
) {
492 if (crtc
->primary
->fb
)
494 if (crtc
->primary
->fb
== fb_helper
->fb
)
498 if (bound
< crtcs_bound
)
504 #ifdef CONFIG_MAGIC_SYSRQ
506 * restore fbcon display for all kms driver's using this helper, used for sysrq
507 * and panic handling.
509 static bool drm_fb_helper_force_kernel_mode(void)
511 bool ret
, error
= false;
512 struct drm_fb_helper
*helper
;
514 if (list_empty(&kernel_fb_helper_list
))
517 list_for_each_entry(helper
, &kernel_fb_helper_list
, kernel_fb_list
) {
518 struct drm_device
*dev
= helper
->dev
;
520 if (dev
->switch_power_state
== DRM_SWITCH_POWER_OFF
)
523 drm_modeset_lock_all(dev
);
524 ret
= restore_fbdev_mode(helper
);
527 drm_modeset_unlock_all(dev
);
532 static void drm_fb_helper_restore_work_fn(struct work_struct
*ignored
)
535 ret
= drm_fb_helper_force_kernel_mode();
537 DRM_ERROR("Failed to restore crtc configuration\n");
539 static DECLARE_WORK(drm_fb_helper_restore_work
, drm_fb_helper_restore_work_fn
);
541 static void drm_fb_helper_sysrq(int dummy1
)
543 schedule_work(&drm_fb_helper_restore_work
);
546 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op
= {
547 .handler
= drm_fb_helper_sysrq
,
548 .help_msg
= "force-fb(V)",
549 .action_msg
= "Restore framebuffer console",
552 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op
= { };
555 static void drm_fb_helper_dpms(struct fb_info
*info
, int dpms_mode
)
557 struct drm_fb_helper
*fb_helper
= info
->par
;
558 struct drm_device
*dev
= fb_helper
->dev
;
559 struct drm_crtc
*crtc
;
560 struct drm_connector
*connector
;
564 * For each CRTC in this fb, turn the connectors on/off.
566 drm_modeset_lock_all(dev
);
567 if (!drm_fb_helper_is_bound(fb_helper
)) {
568 drm_modeset_unlock_all(dev
);
572 for (i
= 0; i
< fb_helper
->crtc_count
; i
++) {
573 crtc
= fb_helper
->crtc_info
[i
].mode_set
.crtc
;
578 /* Walk the connectors & encoders on this fb turning them on/off */
579 for (j
= 0; j
< fb_helper
->connector_count
; j
++) {
580 connector
= fb_helper
->connector_info
[j
]->connector
;
581 connector
->funcs
->dpms(connector
, dpms_mode
);
582 drm_object_property_set_value(&connector
->base
,
583 dev
->mode_config
.dpms_property
, dpms_mode
);
586 drm_modeset_unlock_all(dev
);
590 * drm_fb_helper_blank - implementation for ->fb_blank
591 * @blank: desired blanking state
592 * @info: fbdev registered by the helper
594 int drm_fb_helper_blank(int blank
, struct fb_info
*info
)
596 if (oops_in_progress
)
600 /* Display: On; HSync: On, VSync: On */
601 case FB_BLANK_UNBLANK
:
602 drm_fb_helper_dpms(info
, DRM_MODE_DPMS_ON
);
604 /* Display: Off; HSync: On, VSync: On */
605 case FB_BLANK_NORMAL
:
606 drm_fb_helper_dpms(info
, DRM_MODE_DPMS_STANDBY
);
608 /* Display: Off; HSync: Off, VSync: On */
609 case FB_BLANK_HSYNC_SUSPEND
:
610 drm_fb_helper_dpms(info
, DRM_MODE_DPMS_STANDBY
);
612 /* Display: Off; HSync: On, VSync: Off */
613 case FB_BLANK_VSYNC_SUSPEND
:
614 drm_fb_helper_dpms(info
, DRM_MODE_DPMS_SUSPEND
);
616 /* Display: Off; HSync: Off, VSync: Off */
617 case FB_BLANK_POWERDOWN
:
618 drm_fb_helper_dpms(info
, DRM_MODE_DPMS_OFF
);
623 EXPORT_SYMBOL(drm_fb_helper_blank
);
625 static void drm_fb_helper_crtc_free(struct drm_fb_helper
*helper
)
629 for (i
= 0; i
< helper
->connector_count
; i
++)
630 kfree(helper
->connector_info
[i
]);
631 kfree(helper
->connector_info
);
632 for (i
= 0; i
< helper
->crtc_count
; i
++) {
633 kfree(helper
->crtc_info
[i
].mode_set
.connectors
);
634 if (helper
->crtc_info
[i
].mode_set
.mode
)
635 drm_mode_destroy(helper
->dev
, helper
->crtc_info
[i
].mode_set
.mode
);
637 kfree(helper
->crtc_info
);
641 * drm_fb_helper_prepare - setup a drm_fb_helper structure
643 * @helper: driver-allocated fbdev helper structure to set up
644 * @funcs: pointer to structure of functions associate with this helper
646 * Sets up the bare minimum to make the framebuffer helper usable. This is
647 * useful to implement race-free initialization of the polling helpers.
649 void drm_fb_helper_prepare(struct drm_device
*dev
, struct drm_fb_helper
*helper
,
650 const struct drm_fb_helper_funcs
*funcs
)
652 INIT_LIST_HEAD(&helper
->kernel_fb_list
);
653 helper
->funcs
= funcs
;
656 EXPORT_SYMBOL(drm_fb_helper_prepare
);
659 * drm_fb_helper_init - initialize a drm_fb_helper structure
661 * @fb_helper: driver-allocated fbdev helper structure to initialize
662 * @crtc_count: maximum number of crtcs to support in this fbdev emulation
663 * @max_conn_count: max connector count
665 * This allocates the structures for the fbdev helper with the given limits.
666 * Note that this won't yet touch the hardware (through the driver interfaces)
667 * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
668 * to allow driver writes more control over the exact init sequence.
670 * Drivers must call drm_fb_helper_prepare() before calling this function.
673 * Zero if everything went ok, nonzero otherwise.
675 int drm_fb_helper_init(struct drm_device
*dev
,
676 struct drm_fb_helper
*fb_helper
,
677 int crtc_count
, int max_conn_count
)
679 struct drm_crtc
*crtc
;
682 if (!drm_fbdev_emulation
)
688 fb_helper
->crtc_info
= kcalloc(crtc_count
, sizeof(struct drm_fb_helper_crtc
), GFP_KERNEL
);
689 if (!fb_helper
->crtc_info
)
692 fb_helper
->crtc_count
= crtc_count
;
693 fb_helper
->connector_info
= kcalloc(dev
->mode_config
.num_connector
, sizeof(struct drm_fb_helper_connector
*), GFP_KERNEL
);
694 if (!fb_helper
->connector_info
) {
695 kfree(fb_helper
->crtc_info
);
698 fb_helper
->connector_info_alloc_count
= dev
->mode_config
.num_connector
;
699 fb_helper
->connector_count
= 0;
701 for (i
= 0; i
< crtc_count
; i
++) {
702 fb_helper
->crtc_info
[i
].mode_set
.connectors
=
703 kcalloc(max_conn_count
,
704 sizeof(struct drm_connector
*),
707 if (!fb_helper
->crtc_info
[i
].mode_set
.connectors
)
709 fb_helper
->crtc_info
[i
].mode_set
.num_connectors
= 0;
713 drm_for_each_crtc(crtc
, dev
) {
714 fb_helper
->crtc_info
[i
].mode_set
.crtc
= crtc
;
718 fb_helper
->atomic
= !!drm_core_check_feature(dev
, DRIVER_ATOMIC
);
722 drm_fb_helper_crtc_free(fb_helper
);
725 EXPORT_SYMBOL(drm_fb_helper_init
);
728 * drm_fb_helper_alloc_fbi - allocate fb_info and some of its members
729 * @fb_helper: driver-allocated fbdev helper
731 * A helper to alloc fb_info and the members cmap and apertures. Called
732 * by the driver within the fb_probe fb_helper callback function.
735 * fb_info pointer if things went okay, pointer containing error code
738 struct fb_info
*drm_fb_helper_alloc_fbi(struct drm_fb_helper
*fb_helper
)
740 struct device
*dev
= fb_helper
->dev
->dev
;
741 struct fb_info
*info
;
744 info
= framebuffer_alloc(0, dev
);
746 return ERR_PTR(-ENOMEM
);
748 ret
= fb_alloc_cmap(&info
->cmap
, 256, 0);
752 info
->apertures
= alloc_apertures(1);
753 if (!info
->apertures
) {
758 fb_helper
->fbdev
= info
;
763 fb_dealloc_cmap(&info
->cmap
);
765 framebuffer_release(info
);
768 EXPORT_SYMBOL(drm_fb_helper_alloc_fbi
);
771 * drm_fb_helper_unregister_fbi - unregister fb_info framebuffer device
772 * @fb_helper: driver-allocated fbdev helper
774 * A wrapper around unregister_framebuffer, to release the fb_info
777 void drm_fb_helper_unregister_fbi(struct drm_fb_helper
*fb_helper
)
779 if (fb_helper
&& fb_helper
->fbdev
)
780 unregister_framebuffer(fb_helper
->fbdev
);
782 EXPORT_SYMBOL(drm_fb_helper_unregister_fbi
);
785 * drm_fb_helper_release_fbi - dealloc fb_info and its members
786 * @fb_helper: driver-allocated fbdev helper
788 * A helper to free memory taken by fb_info and the members cmap and
791 void drm_fb_helper_release_fbi(struct drm_fb_helper
*fb_helper
)
794 struct fb_info
*info
= fb_helper
->fbdev
;
798 fb_dealloc_cmap(&info
->cmap
);
799 framebuffer_release(info
);
802 fb_helper
->fbdev
= NULL
;
805 EXPORT_SYMBOL(drm_fb_helper_release_fbi
);
807 void drm_fb_helper_fini(struct drm_fb_helper
*fb_helper
)
809 if (!drm_fbdev_emulation
)
812 if (!list_empty(&fb_helper
->kernel_fb_list
)) {
813 list_del(&fb_helper
->kernel_fb_list
);
814 if (list_empty(&kernel_fb_helper_list
)) {
815 unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op
);
819 drm_fb_helper_crtc_free(fb_helper
);
822 EXPORT_SYMBOL(drm_fb_helper_fini
);
825 * drm_fb_helper_unlink_fbi - wrapper around unlink_framebuffer
826 * @fb_helper: driver-allocated fbdev helper
828 * A wrapper around unlink_framebuffer implemented by fbdev core
830 void drm_fb_helper_unlink_fbi(struct drm_fb_helper
*fb_helper
)
832 if (fb_helper
&& fb_helper
->fbdev
)
833 unlink_framebuffer(fb_helper
->fbdev
);
835 EXPORT_SYMBOL(drm_fb_helper_unlink_fbi
);
838 * drm_fb_helper_sys_read - wrapper around fb_sys_read
839 * @info: fb_info struct pointer
840 * @buf: userspace buffer to read from framebuffer memory
841 * @count: number of bytes to read from framebuffer memory
842 * @ppos: read offset within framebuffer memory
844 * A wrapper around fb_sys_read implemented by fbdev core
846 ssize_t
drm_fb_helper_sys_read(struct fb_info
*info
, char __user
*buf
,
847 size_t count
, loff_t
*ppos
)
849 return fb_sys_read(info
, buf
, count
, ppos
);
851 EXPORT_SYMBOL(drm_fb_helper_sys_read
);
854 * drm_fb_helper_sys_write - wrapper around fb_sys_write
855 * @info: fb_info struct pointer
856 * @buf: userspace buffer to write to framebuffer memory
857 * @count: number of bytes to write to framebuffer memory
858 * @ppos: write offset within framebuffer memory
860 * A wrapper around fb_sys_write implemented by fbdev core
862 ssize_t
drm_fb_helper_sys_write(struct fb_info
*info
, const char __user
*buf
,
863 size_t count
, loff_t
*ppos
)
865 return fb_sys_write(info
, buf
, count
, ppos
);
867 EXPORT_SYMBOL(drm_fb_helper_sys_write
);
870 * drm_fb_helper_sys_fillrect - wrapper around sys_fillrect
871 * @info: fbdev registered by the helper
872 * @rect: info about rectangle to fill
874 * A wrapper around sys_fillrect implemented by fbdev core
876 void drm_fb_helper_sys_fillrect(struct fb_info
*info
,
877 const struct fb_fillrect
*rect
)
879 sys_fillrect(info
, rect
);
881 EXPORT_SYMBOL(drm_fb_helper_sys_fillrect
);
884 * drm_fb_helper_sys_copyarea - wrapper around sys_copyarea
885 * @info: fbdev registered by the helper
886 * @area: info about area to copy
888 * A wrapper around sys_copyarea implemented by fbdev core
890 void drm_fb_helper_sys_copyarea(struct fb_info
*info
,
891 const struct fb_copyarea
*area
)
893 sys_copyarea(info
, area
);
895 EXPORT_SYMBOL(drm_fb_helper_sys_copyarea
);
898 * drm_fb_helper_sys_imageblit - wrapper around sys_imageblit
899 * @info: fbdev registered by the helper
900 * @image: info about image to blit
902 * A wrapper around sys_imageblit implemented by fbdev core
904 void drm_fb_helper_sys_imageblit(struct fb_info
*info
,
905 const struct fb_image
*image
)
907 sys_imageblit(info
, image
);
909 EXPORT_SYMBOL(drm_fb_helper_sys_imageblit
);
912 * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect
913 * @info: fbdev registered by the helper
914 * @rect: info about rectangle to fill
916 * A wrapper around cfb_imageblit implemented by fbdev core
918 void drm_fb_helper_cfb_fillrect(struct fb_info
*info
,
919 const struct fb_fillrect
*rect
)
921 cfb_fillrect(info
, rect
);
923 EXPORT_SYMBOL(drm_fb_helper_cfb_fillrect
);
926 * drm_fb_helper_cfb_copyarea - wrapper around cfb_copyarea
927 * @info: fbdev registered by the helper
928 * @area: info about area to copy
930 * A wrapper around cfb_copyarea implemented by fbdev core
932 void drm_fb_helper_cfb_copyarea(struct fb_info
*info
,
933 const struct fb_copyarea
*area
)
935 cfb_copyarea(info
, area
);
937 EXPORT_SYMBOL(drm_fb_helper_cfb_copyarea
);
940 * drm_fb_helper_cfb_imageblit - wrapper around cfb_imageblit
941 * @info: fbdev registered by the helper
942 * @image: info about image to blit
944 * A wrapper around cfb_imageblit implemented by fbdev core
946 void drm_fb_helper_cfb_imageblit(struct fb_info
*info
,
947 const struct fb_image
*image
)
949 cfb_imageblit(info
, image
);
951 EXPORT_SYMBOL(drm_fb_helper_cfb_imageblit
);
954 * drm_fb_helper_set_suspend - wrapper around fb_set_suspend
955 * @fb_helper: driver-allocated fbdev helper
956 * @state: desired state, zero to resume, non-zero to suspend
958 * A wrapper around fb_set_suspend implemented by fbdev core
960 void drm_fb_helper_set_suspend(struct drm_fb_helper
*fb_helper
, int state
)
962 if (fb_helper
&& fb_helper
->fbdev
)
963 fb_set_suspend(fb_helper
->fbdev
, state
);
965 EXPORT_SYMBOL(drm_fb_helper_set_suspend
);
967 static int setcolreg(struct drm_crtc
*crtc
, u16 red
, u16 green
,
968 u16 blue
, u16 regno
, struct fb_info
*info
)
970 struct drm_fb_helper
*fb_helper
= info
->par
;
971 struct drm_framebuffer
*fb
= fb_helper
->fb
;
974 if (info
->fix
.visual
== FB_VISUAL_TRUECOLOR
) {
977 /* place color in psuedopalette */
980 palette
= (u32
*)info
->pseudo_palette
;
981 red
>>= (16 - info
->var
.red
.length
);
982 green
>>= (16 - info
->var
.green
.length
);
983 blue
>>= (16 - info
->var
.blue
.length
);
984 value
= (red
<< info
->var
.red
.offset
) |
985 (green
<< info
->var
.green
.offset
) |
986 (blue
<< info
->var
.blue
.offset
);
987 if (info
->var
.transp
.length
> 0) {
988 u32 mask
= (1 << info
->var
.transp
.length
) - 1;
989 mask
<<= info
->var
.transp
.offset
;
992 palette
[regno
] = value
;
997 * The driver really shouldn't advertise pseudo/directcolor
998 * visuals if it can't deal with the palette.
1000 if (WARN_ON(!fb_helper
->funcs
->gamma_set
||
1001 !fb_helper
->funcs
->gamma_get
))
1006 if (fb
->bits_per_pixel
== 16) {
1007 pindex
= regno
<< 3;
1009 if (fb
->depth
== 16 && regno
> 63)
1011 if (fb
->depth
== 15 && regno
> 31)
1014 if (fb
->depth
== 16) {
1018 for (i
= 0; i
< 8; i
++)
1019 fb_helper
->funcs
->gamma_set(crtc
, red
,
1020 green
, blue
, pindex
+ i
);
1023 fb_helper
->funcs
->gamma_get(crtc
, &r
,
1027 for (i
= 0; i
< 4; i
++)
1028 fb_helper
->funcs
->gamma_set(crtc
, r
,
1034 if (fb
->depth
!= 16)
1035 fb_helper
->funcs
->gamma_set(crtc
, red
, green
, blue
, pindex
);
1040 * drm_fb_helper_setcmap - implementation for ->fb_setcmap
1041 * @cmap: cmap to set
1042 * @info: fbdev registered by the helper
1044 int drm_fb_helper_setcmap(struct fb_cmap
*cmap
, struct fb_info
*info
)
1046 struct drm_fb_helper
*fb_helper
= info
->par
;
1047 struct drm_device
*dev
= fb_helper
->dev
;
1048 const struct drm_crtc_helper_funcs
*crtc_funcs
;
1049 u16
*red
, *green
, *blue
, *transp
;
1050 struct drm_crtc
*crtc
;
1054 if (oops_in_progress
)
1057 drm_modeset_lock_all(dev
);
1058 if (!drm_fb_helper_is_bound(fb_helper
)) {
1059 drm_modeset_unlock_all(dev
);
1063 for (i
= 0; i
< fb_helper
->crtc_count
; i
++) {
1064 crtc
= fb_helper
->crtc_info
[i
].mode_set
.crtc
;
1065 crtc_funcs
= crtc
->helper_private
;
1068 green
= cmap
->green
;
1070 transp
= cmap
->transp
;
1071 start
= cmap
->start
;
1073 for (j
= 0; j
< cmap
->len
; j
++) {
1074 u16 hred
, hgreen
, hblue
, htransp
= 0xffff;
1081 htransp
= *transp
++;
1083 rc
= setcolreg(crtc
, hred
, hgreen
, hblue
, start
++, info
);
1087 if (crtc_funcs
->load_lut
)
1088 crtc_funcs
->load_lut(crtc
);
1091 drm_modeset_unlock_all(dev
);
1094 EXPORT_SYMBOL(drm_fb_helper_setcmap
);
1097 * drm_fb_helper_check_var - implementation for ->fb_check_var
1098 * @var: screeninfo to check
1099 * @info: fbdev registered by the helper
1101 int drm_fb_helper_check_var(struct fb_var_screeninfo
*var
,
1102 struct fb_info
*info
)
1104 struct drm_fb_helper
*fb_helper
= info
->par
;
1105 struct drm_framebuffer
*fb
= fb_helper
->fb
;
1108 if (var
->pixclock
!= 0 || in_dbg_master())
1111 /* Need to resize the fb object !!! */
1112 if (var
->bits_per_pixel
> fb
->bits_per_pixel
||
1113 var
->xres
> fb
->width
|| var
->yres
> fb
->height
||
1114 var
->xres_virtual
> fb
->width
|| var
->yres_virtual
> fb
->height
) {
1115 DRM_DEBUG("fb userspace requested width/height/bpp is greater than current fb "
1116 "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
1117 var
->xres
, var
->yres
, var
->bits_per_pixel
,
1118 var
->xres_virtual
, var
->yres_virtual
,
1119 fb
->width
, fb
->height
, fb
->bits_per_pixel
);
1123 switch (var
->bits_per_pixel
) {
1125 depth
= (var
->green
.length
== 6) ? 16 : 15;
1128 depth
= (var
->transp
.length
> 0) ? 32 : 24;
1131 depth
= var
->bits_per_pixel
;
1137 var
->red
.offset
= 0;
1138 var
->green
.offset
= 0;
1139 var
->blue
.offset
= 0;
1140 var
->red
.length
= 8;
1141 var
->green
.length
= 8;
1142 var
->blue
.length
= 8;
1143 var
->transp
.length
= 0;
1144 var
->transp
.offset
= 0;
1147 var
->red
.offset
= 10;
1148 var
->green
.offset
= 5;
1149 var
->blue
.offset
= 0;
1150 var
->red
.length
= 5;
1151 var
->green
.length
= 5;
1152 var
->blue
.length
= 5;
1153 var
->transp
.length
= 1;
1154 var
->transp
.offset
= 15;
1157 var
->red
.offset
= 11;
1158 var
->green
.offset
= 5;
1159 var
->blue
.offset
= 0;
1160 var
->red
.length
= 5;
1161 var
->green
.length
= 6;
1162 var
->blue
.length
= 5;
1163 var
->transp
.length
= 0;
1164 var
->transp
.offset
= 0;
1167 var
->red
.offset
= 16;
1168 var
->green
.offset
= 8;
1169 var
->blue
.offset
= 0;
1170 var
->red
.length
= 8;
1171 var
->green
.length
= 8;
1172 var
->blue
.length
= 8;
1173 var
->transp
.length
= 0;
1174 var
->transp
.offset
= 0;
1177 var
->red
.offset
= 16;
1178 var
->green
.offset
= 8;
1179 var
->blue
.offset
= 0;
1180 var
->red
.length
= 8;
1181 var
->green
.length
= 8;
1182 var
->blue
.length
= 8;
1183 var
->transp
.length
= 8;
1184 var
->transp
.offset
= 24;
1191 EXPORT_SYMBOL(drm_fb_helper_check_var
);
1194 * drm_fb_helper_set_par - implementation for ->fb_set_par
1195 * @info: fbdev registered by the helper
1197 * This will let fbcon do the mode init and is called at initialization time by
1198 * the fbdev core when registering the driver, and later on through the hotplug
1201 int drm_fb_helper_set_par(struct fb_info
*info
)
1203 struct drm_fb_helper
*fb_helper
= info
->par
;
1204 struct fb_var_screeninfo
*var
= &info
->var
;
1206 if (oops_in_progress
)
1209 if (var
->pixclock
!= 0) {
1210 DRM_ERROR("PIXEL CLOCK SET\n");
1214 drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper
);
1218 EXPORT_SYMBOL(drm_fb_helper_set_par
);
1220 static int pan_display_atomic(struct fb_var_screeninfo
*var
,
1221 struct fb_info
*info
)
1223 struct drm_fb_helper
*fb_helper
= info
->par
;
1224 struct drm_device
*dev
= fb_helper
->dev
;
1225 struct drm_atomic_state
*state
;
1226 struct drm_plane
*plane
;
1228 unsigned plane_mask
;
1230 state
= drm_atomic_state_alloc(dev
);
1234 state
->acquire_ctx
= dev
->mode_config
.acquire_ctx
;
1237 for(i
= 0; i
< fb_helper
->crtc_count
; i
++) {
1238 struct drm_mode_set
*mode_set
;
1240 mode_set
= &fb_helper
->crtc_info
[i
].mode_set
;
1242 mode_set
->x
= var
->xoffset
;
1243 mode_set
->y
= var
->yoffset
;
1245 ret
= __drm_atomic_helper_set_config(mode_set
, state
);
1249 plane
= mode_set
->crtc
->primary
;
1250 plane_mask
|= (1 << drm_plane_index(plane
));
1251 plane
->old_fb
= plane
->fb
;
1254 ret
= drm_atomic_commit(state
);
1258 info
->var
.xoffset
= var
->xoffset
;
1259 info
->var
.yoffset
= var
->yoffset
;
1263 drm_atomic_clean_old_fb(dev
, plane_mask
, ret
);
1265 if (ret
== -EDEADLK
)
1269 drm_atomic_state_free(state
);
1274 drm_atomic_state_clear(state
);
1275 drm_atomic_legacy_backoff(state
);
1281 * drm_fb_helper_pan_display - implementation for ->fb_pan_display
1282 * @var: updated screen information
1283 * @info: fbdev registered by the helper
1285 int drm_fb_helper_pan_display(struct fb_var_screeninfo
*var
,
1286 struct fb_info
*info
)
1288 struct drm_fb_helper
*fb_helper
= info
->par
;
1289 struct drm_device
*dev
= fb_helper
->dev
;
1290 struct drm_mode_set
*modeset
;
1294 if (oops_in_progress
)
1297 drm_modeset_lock_all(dev
);
1298 if (!drm_fb_helper_is_bound(fb_helper
)) {
1299 drm_modeset_unlock_all(dev
);
1303 if (fb_helper
->atomic
) {
1304 ret
= pan_display_atomic(var
, info
);
1308 for (i
= 0; i
< fb_helper
->crtc_count
; i
++) {
1309 modeset
= &fb_helper
->crtc_info
[i
].mode_set
;
1311 modeset
->x
= var
->xoffset
;
1312 modeset
->y
= var
->yoffset
;
1314 if (modeset
->num_connectors
) {
1315 ret
= drm_mode_set_config_internal(modeset
);
1317 info
->var
.xoffset
= var
->xoffset
;
1318 info
->var
.yoffset
= var
->yoffset
;
1323 drm_modeset_unlock_all(dev
);
1326 EXPORT_SYMBOL(drm_fb_helper_pan_display
);
1329 * Allocates the backing storage and sets up the fbdev info structure through
1330 * the ->fb_probe callback and then registers the fbdev and sets up the panic
1333 static int drm_fb_helper_single_fb_probe(struct drm_fb_helper
*fb_helper
,
1339 struct fb_info
*info
;
1340 struct drm_fb_helper_surface_size sizes
;
1343 memset(&sizes
, 0, sizeof(struct drm_fb_helper_surface_size
));
1344 sizes
.surface_depth
= 24;
1345 sizes
.surface_bpp
= 32;
1346 sizes
.fb_width
= (unsigned)-1;
1347 sizes
.fb_height
= (unsigned)-1;
1349 /* if driver picks 8 or 16 by default use that
1350 for both depth/bpp */
1351 if (preferred_bpp
!= sizes
.surface_bpp
)
1352 sizes
.surface_depth
= sizes
.surface_bpp
= preferred_bpp
;
1354 /* first up get a count of crtcs now in use and new min/maxes width/heights */
1355 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
1356 struct drm_fb_helper_connector
*fb_helper_conn
= fb_helper
->connector_info
[i
];
1357 struct drm_cmdline_mode
*cmdline_mode
;
1359 cmdline_mode
= &fb_helper_conn
->connector
->cmdline_mode
;
1361 if (cmdline_mode
->bpp_specified
) {
1362 switch (cmdline_mode
->bpp
) {
1364 sizes
.surface_depth
= sizes
.surface_bpp
= 8;
1367 sizes
.surface_depth
= 15;
1368 sizes
.surface_bpp
= 16;
1371 sizes
.surface_depth
= sizes
.surface_bpp
= 16;
1374 sizes
.surface_depth
= sizes
.surface_bpp
= 24;
1377 sizes
.surface_depth
= 24;
1378 sizes
.surface_bpp
= 32;
1386 for (i
= 0; i
< fb_helper
->crtc_count
; i
++) {
1387 struct drm_display_mode
*desired_mode
;
1388 struct drm_mode_set
*mode_set
;
1390 /* in case of tile group, are we the last tile vert or horiz?
1391 * If no tile group you are always the last one both vertically
1394 bool lastv
= true, lasth
= true;
1396 desired_mode
= fb_helper
->crtc_info
[i
].desired_mode
;
1397 mode_set
= &fb_helper
->crtc_info
[i
].mode_set
;
1404 x
= fb_helper
->crtc_info
[i
].x
;
1405 y
= fb_helper
->crtc_info
[i
].y
;
1407 if (gamma_size
== 0)
1408 gamma_size
= fb_helper
->crtc_info
[i
].mode_set
.crtc
->gamma_size
;
1410 sizes
.surface_width
= max_t(u32
, desired_mode
->hdisplay
+ x
, sizes
.surface_width
);
1411 sizes
.surface_height
= max_t(u32
, desired_mode
->vdisplay
+ y
, sizes
.surface_height
);
1413 for (j
= 0; j
< mode_set
->num_connectors
; j
++) {
1414 struct drm_connector
*connector
= mode_set
->connectors
[j
];
1415 if (connector
->has_tile
) {
1416 lasth
= (connector
->tile_h_loc
== (connector
->num_h_tile
- 1));
1417 lastv
= (connector
->tile_v_loc
== (connector
->num_v_tile
- 1));
1418 /* cloning to multiple tiles is just crazy-talk, so: */
1424 sizes
.fb_width
= min_t(u32
, desired_mode
->hdisplay
+ x
, sizes
.fb_width
);
1426 sizes
.fb_height
= min_t(u32
, desired_mode
->vdisplay
+ y
, sizes
.fb_height
);
1429 if (crtc_count
== 0 || sizes
.fb_width
== -1 || sizes
.fb_height
== -1) {
1430 /* hmm everyone went away - assume VGA cable just fell out
1431 and will come back later. */
1432 DRM_INFO("Cannot find any crtc or sizes - going 1024x768\n");
1433 sizes
.fb_width
= sizes
.surface_width
= 1024;
1434 sizes
.fb_height
= sizes
.surface_height
= 768;
1437 /* push down into drivers */
1438 ret
= (*fb_helper
->funcs
->fb_probe
)(fb_helper
, &sizes
);
1442 info
= fb_helper
->fbdev
;
1445 * Set the fb pointer - usually drm_setup_crtcs does this for hotplug
1446 * events, but at init time drm_setup_crtcs needs to be called before
1447 * the fb is allocated (since we need to figure out the desired size of
1448 * the fb before we can allocate it ...). Hence we need to fix things up
1451 for (i
= 0; i
< fb_helper
->crtc_count
; i
++)
1452 if (fb_helper
->crtc_info
[i
].mode_set
.num_connectors
)
1453 fb_helper
->crtc_info
[i
].mode_set
.fb
= fb_helper
->fb
;
1456 info
->var
.pixclock
= 0;
1457 if (register_framebuffer(info
) < 0)
1460 dev_info(fb_helper
->dev
->dev
, "fb%d: %s frame buffer device\n",
1461 info
->node
, info
->fix
.id
);
1463 if (list_empty(&kernel_fb_helper_list
)) {
1464 register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op
);
1467 list_add(&fb_helper
->kernel_fb_list
, &kernel_fb_helper_list
);
1473 * drm_fb_helper_fill_fix - initializes fixed fbdev information
1474 * @info: fbdev registered by the helper
1475 * @pitch: desired pitch
1476 * @depth: desired depth
1478 * Helper to fill in the fixed fbdev information useful for a non-accelerated
1479 * fbdev emulations. Drivers which support acceleration methods which impose
1480 * additional constraints need to set up their own limits.
1482 * Drivers should call this (or their equivalent setup code) from their
1483 * ->fb_probe callback.
1485 void drm_fb_helper_fill_fix(struct fb_info
*info
, uint32_t pitch
,
1488 info
->fix
.type
= FB_TYPE_PACKED_PIXELS
;
1489 info
->fix
.visual
= depth
== 8 ? FB_VISUAL_PSEUDOCOLOR
:
1490 FB_VISUAL_TRUECOLOR
;
1491 info
->fix
.mmio_start
= 0;
1492 info
->fix
.mmio_len
= 0;
1493 info
->fix
.type_aux
= 0;
1494 info
->fix
.xpanstep
= 1; /* doing it in hw */
1495 info
->fix
.ypanstep
= 1; /* doing it in hw */
1496 info
->fix
.ywrapstep
= 0;
1497 info
->fix
.accel
= FB_ACCEL_NONE
;
1499 info
->fix
.line_length
= pitch
;
1502 EXPORT_SYMBOL(drm_fb_helper_fill_fix
);
1505 * drm_fb_helper_fill_var - initalizes variable fbdev information
1506 * @info: fbdev instance to set up
1507 * @fb_helper: fb helper instance to use as template
1508 * @fb_width: desired fb width
1509 * @fb_height: desired fb height
1511 * Sets up the variable fbdev metainformation from the given fb helper instance
1512 * and the drm framebuffer allocated in fb_helper->fb.
1514 * Drivers should call this (or their equivalent setup code) from their
1515 * ->fb_probe callback after having allocated the fbdev backing
1516 * storage framebuffer.
1518 void drm_fb_helper_fill_var(struct fb_info
*info
, struct drm_fb_helper
*fb_helper
,
1519 uint32_t fb_width
, uint32_t fb_height
)
1521 struct drm_framebuffer
*fb
= fb_helper
->fb
;
1522 info
->pseudo_palette
= fb_helper
->pseudo_palette
;
1523 info
->var
.xres_virtual
= fb
->width
;
1524 info
->var
.yres_virtual
= fb
->height
;
1525 info
->var
.bits_per_pixel
= fb
->bits_per_pixel
;
1526 info
->var
.accel_flags
= FB_ACCELF_TEXT
;
1527 info
->var
.xoffset
= 0;
1528 info
->var
.yoffset
= 0;
1529 info
->var
.activate
= FB_ACTIVATE_NOW
;
1530 info
->var
.height
= -1;
1531 info
->var
.width
= -1;
1533 switch (fb
->depth
) {
1535 info
->var
.red
.offset
= 0;
1536 info
->var
.green
.offset
= 0;
1537 info
->var
.blue
.offset
= 0;
1538 info
->var
.red
.length
= 8; /* 8bit DAC */
1539 info
->var
.green
.length
= 8;
1540 info
->var
.blue
.length
= 8;
1541 info
->var
.transp
.offset
= 0;
1542 info
->var
.transp
.length
= 0;
1545 info
->var
.red
.offset
= 10;
1546 info
->var
.green
.offset
= 5;
1547 info
->var
.blue
.offset
= 0;
1548 info
->var
.red
.length
= 5;
1549 info
->var
.green
.length
= 5;
1550 info
->var
.blue
.length
= 5;
1551 info
->var
.transp
.offset
= 15;
1552 info
->var
.transp
.length
= 1;
1555 info
->var
.red
.offset
= 11;
1556 info
->var
.green
.offset
= 5;
1557 info
->var
.blue
.offset
= 0;
1558 info
->var
.red
.length
= 5;
1559 info
->var
.green
.length
= 6;
1560 info
->var
.blue
.length
= 5;
1561 info
->var
.transp
.offset
= 0;
1564 info
->var
.red
.offset
= 16;
1565 info
->var
.green
.offset
= 8;
1566 info
->var
.blue
.offset
= 0;
1567 info
->var
.red
.length
= 8;
1568 info
->var
.green
.length
= 8;
1569 info
->var
.blue
.length
= 8;
1570 info
->var
.transp
.offset
= 0;
1571 info
->var
.transp
.length
= 0;
1574 info
->var
.red
.offset
= 16;
1575 info
->var
.green
.offset
= 8;
1576 info
->var
.blue
.offset
= 0;
1577 info
->var
.red
.length
= 8;
1578 info
->var
.green
.length
= 8;
1579 info
->var
.blue
.length
= 8;
1580 info
->var
.transp
.offset
= 24;
1581 info
->var
.transp
.length
= 8;
1587 info
->var
.xres
= fb_width
;
1588 info
->var
.yres
= fb_height
;
1590 EXPORT_SYMBOL(drm_fb_helper_fill_var
);
1592 static int drm_fb_helper_probe_connector_modes(struct drm_fb_helper
*fb_helper
,
1596 struct drm_connector
*connector
;
1600 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
1601 connector
= fb_helper
->connector_info
[i
]->connector
;
1602 count
+= connector
->funcs
->fill_modes(connector
, maxX
, maxY
);
1608 struct drm_display_mode
*drm_has_preferred_mode(struct drm_fb_helper_connector
*fb_connector
, int width
, int height
)
1610 struct drm_display_mode
*mode
;
1612 list_for_each_entry(mode
, &fb_connector
->connector
->modes
, head
) {
1613 if (mode
->hdisplay
> width
||
1614 mode
->vdisplay
> height
)
1616 if (mode
->type
& DRM_MODE_TYPE_PREFERRED
)
1621 EXPORT_SYMBOL(drm_has_preferred_mode
);
1623 static bool drm_has_cmdline_mode(struct drm_fb_helper_connector
*fb_connector
)
1625 return fb_connector
->connector
->cmdline_mode
.specified
;
1628 struct drm_display_mode
*drm_pick_cmdline_mode(struct drm_fb_helper_connector
*fb_helper_conn
,
1629 int width
, int height
)
1631 struct drm_cmdline_mode
*cmdline_mode
;
1632 struct drm_display_mode
*mode
;
1633 bool prefer_non_interlace
;
1635 cmdline_mode
= &fb_helper_conn
->connector
->cmdline_mode
;
1636 if (cmdline_mode
->specified
== false)
1639 /* attempt to find a matching mode in the list of modes
1640 * we have gotten so far, if not add a CVT mode that conforms
1642 if (cmdline_mode
->rb
|| cmdline_mode
->margins
)
1645 prefer_non_interlace
= !cmdline_mode
->interlace
;
1647 list_for_each_entry(mode
, &fb_helper_conn
->connector
->modes
, head
) {
1648 /* check width/height */
1649 if (mode
->hdisplay
!= cmdline_mode
->xres
||
1650 mode
->vdisplay
!= cmdline_mode
->yres
)
1653 if (cmdline_mode
->refresh_specified
) {
1654 if (mode
->vrefresh
!= cmdline_mode
->refresh
)
1658 if (cmdline_mode
->interlace
) {
1659 if (!(mode
->flags
& DRM_MODE_FLAG_INTERLACE
))
1661 } else if (prefer_non_interlace
) {
1662 if (mode
->flags
& DRM_MODE_FLAG_INTERLACE
)
1668 if (prefer_non_interlace
) {
1669 prefer_non_interlace
= false;
1674 mode
= drm_mode_create_from_cmdline_mode(fb_helper_conn
->connector
->dev
,
1676 list_add(&mode
->head
, &fb_helper_conn
->connector
->modes
);
1679 EXPORT_SYMBOL(drm_pick_cmdline_mode
);
1681 static bool drm_connector_enabled(struct drm_connector
*connector
, bool strict
)
1686 enable
= connector
->status
== connector_status_connected
;
1688 enable
= connector
->status
!= connector_status_disconnected
;
1693 static void drm_enable_connectors(struct drm_fb_helper
*fb_helper
,
1696 bool any_enabled
= false;
1697 struct drm_connector
*connector
;
1700 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
1701 connector
= fb_helper
->connector_info
[i
]->connector
;
1702 enabled
[i
] = drm_connector_enabled(connector
, true);
1703 DRM_DEBUG_KMS("connector %d enabled? %s\n", connector
->base
.id
,
1704 enabled
[i
] ? "yes" : "no");
1705 any_enabled
|= enabled
[i
];
1711 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
1712 connector
= fb_helper
->connector_info
[i
]->connector
;
1713 enabled
[i
] = drm_connector_enabled(connector
, false);
1717 static bool drm_target_cloned(struct drm_fb_helper
*fb_helper
,
1718 struct drm_display_mode
**modes
,
1719 struct drm_fb_offset
*offsets
,
1720 bool *enabled
, int width
, int height
)
1723 bool can_clone
= false;
1724 struct drm_fb_helper_connector
*fb_helper_conn
;
1725 struct drm_display_mode
*dmt_mode
, *mode
;
1727 /* only contemplate cloning in the single crtc case */
1728 if (fb_helper
->crtc_count
> 1)
1732 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
1737 /* only contemplate cloning if more than one connector is enabled */
1741 /* check the command line or if nothing common pick 1024x768 */
1743 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
1746 fb_helper_conn
= fb_helper
->connector_info
[i
];
1747 modes
[i
] = drm_pick_cmdline_mode(fb_helper_conn
, width
, height
);
1752 for (j
= 0; j
< i
; j
++) {
1755 if (!drm_mode_equal(modes
[j
], modes
[i
]))
1761 DRM_DEBUG_KMS("can clone using command line\n");
1765 /* try and find a 1024x768 mode on each connector */
1767 dmt_mode
= drm_mode_find_dmt(fb_helper
->dev
, 1024, 768, 60, false);
1769 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
1774 fb_helper_conn
= fb_helper
->connector_info
[i
];
1775 list_for_each_entry(mode
, &fb_helper_conn
->connector
->modes
, head
) {
1776 if (drm_mode_equal(mode
, dmt_mode
))
1784 DRM_DEBUG_KMS("can clone using 1024x768\n");
1787 DRM_INFO("kms: can't enable cloning when we probably wanted to.\n");
1791 static int drm_get_tile_offsets(struct drm_fb_helper
*fb_helper
,
1792 struct drm_display_mode
**modes
,
1793 struct drm_fb_offset
*offsets
,
1795 int h_idx
, int v_idx
)
1797 struct drm_fb_helper_connector
*fb_helper_conn
;
1799 int hoffset
= 0, voffset
= 0;
1801 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
1802 fb_helper_conn
= fb_helper
->connector_info
[i
];
1803 if (!fb_helper_conn
->connector
->has_tile
)
1806 if (!modes
[i
] && (h_idx
|| v_idx
)) {
1807 DRM_DEBUG_KMS("no modes for connector tiled %d %d\n", i
,
1808 fb_helper_conn
->connector
->base
.id
);
1811 if (fb_helper_conn
->connector
->tile_h_loc
< h_idx
)
1812 hoffset
+= modes
[i
]->hdisplay
;
1814 if (fb_helper_conn
->connector
->tile_v_loc
< v_idx
)
1815 voffset
+= modes
[i
]->vdisplay
;
1817 offsets
[idx
].x
= hoffset
;
1818 offsets
[idx
].y
= voffset
;
1819 DRM_DEBUG_KMS("returned %d %d for %d %d\n", hoffset
, voffset
, h_idx
, v_idx
);
1823 static bool drm_target_preferred(struct drm_fb_helper
*fb_helper
,
1824 struct drm_display_mode
**modes
,
1825 struct drm_fb_offset
*offsets
,
1826 bool *enabled
, int width
, int height
)
1828 struct drm_fb_helper_connector
*fb_helper_conn
;
1830 uint64_t conn_configured
= 0, mask
;
1832 mask
= (1 << fb_helper
->connector_count
) - 1;
1834 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
1835 fb_helper_conn
= fb_helper
->connector_info
[i
];
1837 if (conn_configured
& (1 << i
))
1840 if (enabled
[i
] == false) {
1841 conn_configured
|= (1 << i
);
1845 /* first pass over all the untiled connectors */
1846 if (tile_pass
== 0 && fb_helper_conn
->connector
->has_tile
)
1849 if (tile_pass
== 1) {
1850 if (fb_helper_conn
->connector
->tile_h_loc
!= 0 ||
1851 fb_helper_conn
->connector
->tile_v_loc
!= 0)
1855 if (fb_helper_conn
->connector
->tile_h_loc
!= tile_pass
-1 &&
1856 fb_helper_conn
->connector
->tile_v_loc
!= tile_pass
- 1)
1857 /* if this tile_pass doesn't cover any of the tiles - keep going */
1860 /* find the tile offsets for this pass - need
1861 to find all tiles left and above */
1862 drm_get_tile_offsets(fb_helper
, modes
, offsets
,
1863 i
, fb_helper_conn
->connector
->tile_h_loc
, fb_helper_conn
->connector
->tile_v_loc
);
1865 DRM_DEBUG_KMS("looking for cmdline mode on connector %d\n",
1866 fb_helper_conn
->connector
->base
.id
);
1868 /* got for command line mode first */
1869 modes
[i
] = drm_pick_cmdline_mode(fb_helper_conn
, width
, height
);
1871 DRM_DEBUG_KMS("looking for preferred mode on connector %d %d\n",
1872 fb_helper_conn
->connector
->base
.id
, fb_helper_conn
->connector
->tile_group
? fb_helper_conn
->connector
->tile_group
->id
: 0);
1873 modes
[i
] = drm_has_preferred_mode(fb_helper_conn
, width
, height
);
1875 /* No preferred modes, pick one off the list */
1876 if (!modes
[i
] && !list_empty(&fb_helper_conn
->connector
->modes
)) {
1877 list_for_each_entry(modes
[i
], &fb_helper_conn
->connector
->modes
, head
)
1880 DRM_DEBUG_KMS("found mode %s\n", modes
[i
] ? modes
[i
]->name
:
1882 conn_configured
|= (1 << i
);
1885 if ((conn_configured
& mask
) != mask
) {
1892 static int drm_pick_crtcs(struct drm_fb_helper
*fb_helper
,
1893 struct drm_fb_helper_crtc
**best_crtcs
,
1894 struct drm_display_mode
**modes
,
1895 int n
, int width
, int height
)
1898 struct drm_device
*dev
= fb_helper
->dev
;
1899 struct drm_connector
*connector
;
1900 const struct drm_connector_helper_funcs
*connector_funcs
;
1901 struct drm_encoder
*encoder
;
1902 int my_score
, best_score
, score
;
1903 struct drm_fb_helper_crtc
**crtcs
, *crtc
;
1904 struct drm_fb_helper_connector
*fb_helper_conn
;
1906 if (n
== fb_helper
->connector_count
)
1909 fb_helper_conn
= fb_helper
->connector_info
[n
];
1910 connector
= fb_helper_conn
->connector
;
1912 best_crtcs
[n
] = NULL
;
1913 best_score
= drm_pick_crtcs(fb_helper
, best_crtcs
, modes
, n
+1, width
, height
);
1914 if (modes
[n
] == NULL
)
1917 crtcs
= kzalloc(dev
->mode_config
.num_connector
*
1918 sizeof(struct drm_fb_helper_crtc
*), GFP_KERNEL
);
1923 if (connector
->status
== connector_status_connected
)
1925 if (drm_has_cmdline_mode(fb_helper_conn
))
1927 if (drm_has_preferred_mode(fb_helper_conn
, width
, height
))
1930 connector_funcs
= connector
->helper_private
;
1931 encoder
= connector_funcs
->best_encoder(connector
);
1935 /* select a crtc for this connector and then attempt to configure
1936 remaining connectors */
1937 for (c
= 0; c
< fb_helper
->crtc_count
; c
++) {
1938 crtc
= &fb_helper
->crtc_info
[c
];
1940 if ((encoder
->possible_crtcs
& (1 << c
)) == 0)
1943 for (o
= 0; o
< n
; o
++)
1944 if (best_crtcs
[o
] == crtc
)
1948 /* ignore cloning unless only a single crtc */
1949 if (fb_helper
->crtc_count
> 1)
1952 if (!drm_mode_equal(modes
[o
], modes
[n
]))
1957 memcpy(crtcs
, best_crtcs
, n
* sizeof(struct drm_fb_helper_crtc
*));
1958 score
= my_score
+ drm_pick_crtcs(fb_helper
, crtcs
, modes
, n
+ 1,
1960 if (score
> best_score
) {
1962 memcpy(best_crtcs
, crtcs
,
1963 dev
->mode_config
.num_connector
*
1964 sizeof(struct drm_fb_helper_crtc
*));
1972 static void drm_setup_crtcs(struct drm_fb_helper
*fb_helper
)
1974 struct drm_device
*dev
= fb_helper
->dev
;
1975 struct drm_fb_helper_crtc
**crtcs
;
1976 struct drm_display_mode
**modes
;
1977 struct drm_fb_offset
*offsets
;
1978 struct drm_mode_set
*modeset
;
1983 DRM_DEBUG_KMS("\n");
1985 width
= dev
->mode_config
.max_width
;
1986 height
= dev
->mode_config
.max_height
;
1988 crtcs
= kcalloc(fb_helper
->connector_count
,
1989 sizeof(struct drm_fb_helper_crtc
*), GFP_KERNEL
);
1990 modes
= kcalloc(fb_helper
->connector_count
,
1991 sizeof(struct drm_display_mode
*), GFP_KERNEL
);
1992 offsets
= kcalloc(fb_helper
->connector_count
,
1993 sizeof(struct drm_fb_offset
), GFP_KERNEL
);
1994 enabled
= kcalloc(fb_helper
->connector_count
,
1995 sizeof(bool), GFP_KERNEL
);
1996 if (!crtcs
|| !modes
|| !enabled
|| !offsets
) {
1997 DRM_ERROR("Memory allocation failed\n");
2002 drm_enable_connectors(fb_helper
, enabled
);
2004 if (!(fb_helper
->funcs
->initial_config
&&
2005 fb_helper
->funcs
->initial_config(fb_helper
, crtcs
, modes
,
2007 enabled
, width
, height
))) {
2008 memset(modes
, 0, fb_helper
->connector_count
*sizeof(modes
[0]));
2009 memset(crtcs
, 0, fb_helper
->connector_count
*sizeof(crtcs
[0]));
2010 memset(offsets
, 0, fb_helper
->connector_count
*sizeof(offsets
[0]));
2012 if (!drm_target_cloned(fb_helper
, modes
, offsets
,
2013 enabled
, width
, height
) &&
2014 !drm_target_preferred(fb_helper
, modes
, offsets
,
2015 enabled
, width
, height
))
2016 DRM_ERROR("Unable to find initial modes\n");
2018 DRM_DEBUG_KMS("picking CRTCs for %dx%d config\n",
2021 drm_pick_crtcs(fb_helper
, crtcs
, modes
, 0, width
, height
);
2024 /* need to set the modesets up here for use later */
2025 /* fill out the connector<->crtc mappings into the modesets */
2026 for (i
= 0; i
< fb_helper
->crtc_count
; i
++) {
2027 modeset
= &fb_helper
->crtc_info
[i
].mode_set
;
2028 modeset
->num_connectors
= 0;
2032 for (i
= 0; i
< fb_helper
->connector_count
; i
++) {
2033 struct drm_display_mode
*mode
= modes
[i
];
2034 struct drm_fb_helper_crtc
*fb_crtc
= crtcs
[i
];
2035 struct drm_fb_offset
*offset
= &offsets
[i
];
2036 modeset
= &fb_crtc
->mode_set
;
2038 if (mode
&& fb_crtc
) {
2039 DRM_DEBUG_KMS("desired mode %s set on crtc %d (%d,%d)\n",
2040 mode
->name
, fb_crtc
->mode_set
.crtc
->base
.id
, offset
->x
, offset
->y
);
2041 fb_crtc
->desired_mode
= mode
;
2042 fb_crtc
->x
= offset
->x
;
2043 fb_crtc
->y
= offset
->y
;
2045 drm_mode_destroy(dev
, modeset
->mode
);
2046 modeset
->mode
= drm_mode_duplicate(dev
,
2047 fb_crtc
->desired_mode
);
2048 modeset
->connectors
[modeset
->num_connectors
++] = fb_helper
->connector_info
[i
]->connector
;
2049 modeset
->fb
= fb_helper
->fb
;
2050 modeset
->x
= offset
->x
;
2051 modeset
->y
= offset
->y
;
2055 /* Clear out any old modes if there are no more connected outputs. */
2056 for (i
= 0; i
< fb_helper
->crtc_count
; i
++) {
2057 modeset
= &fb_helper
->crtc_info
[i
].mode_set
;
2058 if (modeset
->num_connectors
== 0) {
2059 BUG_ON(modeset
->fb
);
2061 drm_mode_destroy(dev
, modeset
->mode
);
2062 modeset
->mode
= NULL
;
2073 * drm_fb_helper_initial_config - setup a sane initial connector configuration
2074 * @fb_helper: fb_helper device struct
2075 * @bpp_sel: bpp value to use for the framebuffer configuration
2077 * Scans the CRTCs and connectors and tries to put together an initial setup.
2078 * At the moment, this is a cloned configuration across all heads with
2079 * a new framebuffer object as the backing store.
2081 * Note that this also registers the fbdev and so allows userspace to call into
2082 * the driver through the fbdev interfaces.
2084 * This function will call down into the ->fb_probe callback to let
2085 * the driver allocate and initialize the fbdev info structure and the drm
2086 * framebuffer used to back the fbdev. drm_fb_helper_fill_var() and
2087 * drm_fb_helper_fill_fix() are provided as helpers to setup simple default
2088 * values for the fbdev info structure.
2092 * When you have fbcon support built-in or already loaded, this function will do
2093 * a full modeset to setup the fbdev console. Due to locking misdesign in the
2094 * VT/fbdev subsystem that entire modeset sequence has to be done while holding
2095 * console_lock. Until console_unlock is called no dmesg lines will be sent out
2096 * to consoles, not even serial console. This means when your driver crashes,
2097 * you will see absolutely nothing else but a system stuck in this function,
2098 * with no further output. Any kind of printk() you place within your own driver
2099 * or in the drm core modeset code will also never show up.
2101 * Standard debug practice is to run the fbcon setup without taking the
2102 * console_lock as a hack, to be able to see backtraces and crashes on the
2103 * serial line. This can be done by setting the fb.lockless_register_fb=1 kernel
2106 * The other option is to just disable fbdev emulation since very likely the
2107 * first modest from userspace will crash in the same way, and is even easier to
2108 * debug. This can be done by setting the drm_kms_helper.fbdev_emulation=0
2109 * kernel cmdline option.
2112 * Zero if everything went ok, nonzero otherwise.
2114 int drm_fb_helper_initial_config(struct drm_fb_helper
*fb_helper
, int bpp_sel
)
2116 struct drm_device
*dev
= fb_helper
->dev
;
2119 if (!drm_fbdev_emulation
)
2122 mutex_lock(&dev
->mode_config
.mutex
);
2123 count
= drm_fb_helper_probe_connector_modes(fb_helper
,
2124 dev
->mode_config
.max_width
,
2125 dev
->mode_config
.max_height
);
2126 mutex_unlock(&dev
->mode_config
.mutex
);
2128 * we shouldn't end up with no modes here.
2131 dev_info(fb_helper
->dev
->dev
, "No connectors reported connected with modes\n");
2133 drm_setup_crtcs(fb_helper
);
2135 return drm_fb_helper_single_fb_probe(fb_helper
, bpp_sel
);
2137 EXPORT_SYMBOL(drm_fb_helper_initial_config
);
2140 * drm_fb_helper_hotplug_event - respond to a hotplug notification by
2141 * probing all the outputs attached to the fb
2142 * @fb_helper: the drm_fb_helper
2144 * Scan the connectors attached to the fb_helper and try to put together a
2145 * setup after *notification of a change in output configuration.
2147 * Called at runtime, takes the mode config locks to be able to check/change the
2148 * modeset configuration. Must be run from process context (which usually means
2149 * either the output polling work or a work item launched from the driver's
2150 * hotplug interrupt).
2152 * Note that drivers may call this even before calling
2153 * drm_fb_helper_initial_config but only aftert drm_fb_helper_init. This allows
2154 * for a race-free fbcon setup and will make sure that the fbdev emulation will
2155 * not miss any hotplug events.
2158 * 0 on success and a non-zero error code otherwise.
2160 int drm_fb_helper_hotplug_event(struct drm_fb_helper
*fb_helper
)
2162 struct drm_device
*dev
= fb_helper
->dev
;
2163 u32 max_width
, max_height
;
2165 if (!drm_fbdev_emulation
)
2168 mutex_lock(&fb_helper
->dev
->mode_config
.mutex
);
2169 if (!fb_helper
->fb
|| !drm_fb_helper_is_bound(fb_helper
)) {
2170 fb_helper
->delayed_hotplug
= true;
2171 mutex_unlock(&fb_helper
->dev
->mode_config
.mutex
);
2174 DRM_DEBUG_KMS("\n");
2176 max_width
= fb_helper
->fb
->width
;
2177 max_height
= fb_helper
->fb
->height
;
2179 drm_fb_helper_probe_connector_modes(fb_helper
, max_width
, max_height
);
2180 mutex_unlock(&fb_helper
->dev
->mode_config
.mutex
);
2182 drm_modeset_lock_all(dev
);
2183 drm_setup_crtcs(fb_helper
);
2184 drm_modeset_unlock_all(dev
);
2185 drm_fb_helper_set_par(fb_helper
->fbdev
);
2189 EXPORT_SYMBOL(drm_fb_helper_hotplug_event
);
2191 /* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
2192 * but the module doesn't depend on any fb console symbols. At least
2193 * attempt to load fbcon to avoid leaving the system without a usable console.
2195 int __init
drm_fb_helper_modinit(void)
2197 #if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT)
2198 const char *name
= "fbcon";
2199 struct module
*fbcon
;
2201 mutex_lock(&module_mutex
);
2202 fbcon
= find_module(name
);
2203 mutex_unlock(&module_mutex
);
2206 request_module_nowait(name
);
2210 EXPORT_SYMBOL(drm_fb_helper_modinit
);