Files
linux/drivers/gpu/drm/sysfb/drm_sysfb_screen_info.c
Thomas Zimmermann b3728905dc drm/sysfb: Generalize pixel-format matching
Provide drm_sysfb_get_format(), a helper that finds a specific DRM
format from a list of pixel formats. The new function builds upon
drm_sysfb_get_format_si(), which finds the DRM format from a given
instance of struct screen_info. Now get the screen_info's pixel format
in the caller. Allows for matching pixel formats in drivers without
screen_info.

Convert the callers in efidrm and vesadrm to the new interface.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Julius Werner <jwerner@chromium.org>
Link: https://patch.msgid.link/20260217155836.96267-11-tzimmermann@suse.de
2026-02-20 14:38:23 +01:00

75 lines
2.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/export.h>
#include <linux/limits.h>
#include <linux/minmax.h>
#include <linux/screen_info.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_print.h>
#include "drm_sysfb_helper.h"
static s64 drm_sysfb_get_validated_size0(struct drm_device *dev, const char *name,
u64 value, u64 max)
{
if (!value) {
drm_warn(dev, "%s of 0 not allowed\n", name);
return -EINVAL;
} else if (value > min(max, S64_MAX)) {
drm_warn(dev, "%s of %llu exceeds maximum of %llu\n", name, value, max);
return -EINVAL;
}
return value;
}
int drm_sysfb_get_width_si(struct drm_device *dev, const struct screen_info *si)
{
return drm_sysfb_get_validated_int0(dev, "width", si->lfb_width, U16_MAX);
}
EXPORT_SYMBOL(drm_sysfb_get_width_si);
int drm_sysfb_get_height_si(struct drm_device *dev, const struct screen_info *si)
{
return drm_sysfb_get_validated_int0(dev, "height", si->lfb_height, U16_MAX);
}
EXPORT_SYMBOL(drm_sysfb_get_height_si);
struct resource *drm_sysfb_get_memory_si(struct drm_device *dev,
const struct screen_info *si,
struct resource *res)
{
ssize_t num;
num = screen_info_resources(si, res, 1);
if (!num) {
drm_warn(dev, "memory resource not found\n");
return NULL;
}
return res;
}
EXPORT_SYMBOL(drm_sysfb_get_memory_si);
int drm_sysfb_get_stride_si(struct drm_device *dev, const struct screen_info *si,
const struct drm_format_info *format,
unsigned int width, unsigned int height, u64 size)
{
u64 lfb_linelength = si->lfb_linelength;
if (!lfb_linelength)
lfb_linelength = drm_format_info_min_pitch(format, 0, width);
return drm_sysfb_get_validated_int0(dev, "stride", lfb_linelength, div64_u64(size, height));
}
EXPORT_SYMBOL(drm_sysfb_get_stride_si);
u64 drm_sysfb_get_visible_size_si(struct drm_device *dev, const struct screen_info *si,
unsigned int height, unsigned int stride, u64 size)
{
u64 vsize = PAGE_ALIGN(height * stride);
return drm_sysfb_get_validated_size0(dev, "visible size", vsize, size);
}
EXPORT_SYMBOL(drm_sysfb_get_visible_size_si);