linux-stable/drivers/firmware/sysfb.c
Javier Martinez Canillas 8633ef82f1 drivers/firmware: consolidate EFI framebuffer setup for all arches
The register_gop_device() function registers an "efi-framebuffer" platform
device to match against the efifb driver, to have an early framebuffer for
EFI platforms.

But there is already support to do exactly the same by the Generic System
Framebuffers (sysfb) driver. This used to be only for X86 but it has been
moved to drivers/firmware and could be reused by other architectures.

Also, besides supporting registering an "efi-framebuffer", this driver can
register a "simple-framebuffer" allowing to use the siple{fb,drm} drivers
on non-X86 EFI platforms. For example, on aarch64 these drivers can only
be used with DT and doesn't have code to register a "simple-frambuffer"
platform device when booting with EFI.

For these reasons, let's remove the register_gop_device() duplicated code
and instead move the platform specific logic that's there to sysfb driver.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625131359.1804394-1-javierm@redhat.com
2021-07-21 12:04:56 +02:00

83 lines
2.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Generic System Framebuffers
* Copyright (c) 2012-2013 David Herrmann <dh.herrmann@gmail.com>
*/
/*
* Simple-Framebuffer support
* Create a platform-device for any available boot framebuffer. The
* simple-framebuffer platform device is already available on DT systems, so
* this module parses the global "screen_info" object and creates a suitable
* platform device compatible with the "simple-framebuffer" DT object. If
* the framebuffer is incompatible, we instead create a legacy
* "vesa-framebuffer", "efi-framebuffer" or "platform-framebuffer" device and
* pass the screen_info as platform_data. This allows legacy drivers
* to pick these devices up without messing with simple-framebuffer drivers.
* The global "screen_info" is still valid at all times.
*
* If CONFIG_SYSFB_SIMPLEFB is not selected, never register "simple-framebuffer"
* platform devices, but only use legacy framebuffer devices for
* backwards compatibility.
*
* TODO: We set the dev_id field of all platform-devices to 0. This allows
* other OF/DT parsers to create such devices, too. However, they must
* start at offset 1 for this to work.
*/
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/platform_data/simplefb.h>
#include <linux/platform_device.h>
#include <linux/screen_info.h>
#include <linux/sysfb.h>
static __init int sysfb_init(void)
{
struct screen_info *si = &screen_info;
struct simplefb_platform_data mode;
struct platform_device *pd;
const char *name;
bool compatible;
int ret;
/* try to create a simple-framebuffer device */
compatible = sysfb_parse_mode(si, &mode);
if (compatible) {
ret = sysfb_create_simplefb(si, &mode);
if (!ret)
return 0;
}
/* if the FB is incompatible, create a legacy framebuffer device */
if (si->orig_video_isVGA == VIDEO_TYPE_EFI)
name = "efi-framebuffer";
else if (si->orig_video_isVGA == VIDEO_TYPE_VLFB)
name = "vesa-framebuffer";
else
name = "platform-framebuffer";
pd = platform_device_alloc(name, 0);
if (!pd)
return -ENOMEM;
sysfb_apply_efi_quirks(pd);
ret = platform_device_add_data(pd, si, sizeof(*si));
if (ret)
goto err;
ret = platform_device_add(pd);
if (ret)
goto err;
return 0;
err:
platform_device_put(pd);
return ret;
}
/* must execute after PCI subsystem for EFI quirks */
device_initcall(sysfb_init);