drm: fb-helper: Reject all pixel format changing requests

drm fbdev emulation doesn't support changing the pixel format at all,
so reject all pixel format changing requests.

Cc: stable@vger.kernel.org
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20181003164538.5534-1-Eugeniy.Paltsev@synopsys.com
This commit is contained in:
Eugeniy Paltsev 2018-10-03 19:45:38 +03:00 committed by Daniel Vetter
parent 0711a43b6d
commit db05c48197

View File

@ -1580,6 +1580,25 @@ unlock:
}
EXPORT_SYMBOL(drm_fb_helper_ioctl);
static bool drm_fb_pixel_format_equal(const struct fb_var_screeninfo *var_1,
const struct fb_var_screeninfo *var_2)
{
return var_1->bits_per_pixel == var_2->bits_per_pixel &&
var_1->grayscale == var_2->grayscale &&
var_1->red.offset == var_2->red.offset &&
var_1->red.length == var_2->red.length &&
var_1->red.msb_right == var_2->red.msb_right &&
var_1->green.offset == var_2->green.offset &&
var_1->green.length == var_2->green.length &&
var_1->green.msb_right == var_2->green.msb_right &&
var_1->blue.offset == var_2->blue.offset &&
var_1->blue.length == var_2->blue.length &&
var_1->blue.msb_right == var_2->blue.msb_right &&
var_1->transp.offset == var_2->transp.offset &&
var_1->transp.length == var_2->transp.length &&
var_1->transp.msb_right == var_2->transp.msb_right;
}
/**
* drm_fb_helper_check_var - implementation for &fb_ops.fb_check_var
* @var: screeninfo to check
@ -1590,7 +1609,6 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
{
struct drm_fb_helper *fb_helper = info->par;
struct drm_framebuffer *fb = fb_helper->fb;
int depth;
if (var->pixclock != 0 || in_dbg_master())
return -EINVAL;
@ -1610,72 +1628,15 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
return -EINVAL;
}
switch (var->bits_per_pixel) {
case 16:
depth = (var->green.length == 6) ? 16 : 15;
break;
case 32:
depth = (var->transp.length > 0) ? 32 : 24;
break;
default:
depth = var->bits_per_pixel;
break;
}
switch (depth) {
case 8:
var->red.offset = 0;
var->green.offset = 0;
var->blue.offset = 0;
var->red.length = 8;
var->green.length = 8;
var->blue.length = 8;
var->transp.length = 0;
var->transp.offset = 0;
break;
case 15:
var->red.offset = 10;
var->green.offset = 5;
var->blue.offset = 0;
var->red.length = 5;
var->green.length = 5;
var->blue.length = 5;
var->transp.length = 1;
var->transp.offset = 15;
break;
case 16:
var->red.offset = 11;
var->green.offset = 5;
var->blue.offset = 0;
var->red.length = 5;
var->green.length = 6;
var->blue.length = 5;
var->transp.length = 0;
var->transp.offset = 0;
break;
case 24:
var->red.offset = 16;
var->green.offset = 8;
var->blue.offset = 0;
var->red.length = 8;
var->green.length = 8;
var->blue.length = 8;
var->transp.length = 0;
var->transp.offset = 0;
break;
case 32:
var->red.offset = 16;
var->green.offset = 8;
var->blue.offset = 0;
var->red.length = 8;
var->green.length = 8;
var->blue.length = 8;
var->transp.length = 8;
var->transp.offset = 24;
break;
default:
/*
* drm fbdev emulation doesn't support changing the pixel format at all,
* so reject all pixel format changing requests.
*/
if (!drm_fb_pixel_format_equal(var, &info->var)) {
DRM_DEBUG("fbdev emulation doesn't support changing the pixel format\n");
return -EINVAL;
}
return 0;
}
EXPORT_SYMBOL(drm_fb_helper_check_var);