FAILED: patch "[PATCH] drm/gma500: Remove unused helper psb_fbdev_fb_setcolreg()" failed to apply to 5.15-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x be729f9de6c64240645dc80a24162ac4d3fe00a8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026010530-sitcom-outdated-cc0f@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From be729f9de6c64240645dc80a24162ac4d3fe00a8 Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <tzimmermann@suse.de>
Date: Mon, 29 Sep 2025 10:23:23 +0200
Subject: [PATCH] drm/gma500: Remove unused helper psb_fbdev_fb_setcolreg()

Remove psb_fbdev_fb_setcolreg(), which hasn't been called in almost
a decade.

Gma500 commit 4d8d096e9ae8 ("gma500: introduce the framebuffer support
code") added the helper psb_fbdev_fb_setcolreg() for setting the fbdev
palette via fbdev's fb_setcolreg callback. Later
commit 3da6c2f3b730 ("drm/gma500: use DRM_FB_HELPER_DEFAULT_OPS for
fb_ops") set several default helpers for fbdev emulation, including
fb_setcmap.

The fbdev subsystem always prefers fb_setcmap over fb_setcolreg. [1]
Hence, the gma500 code is no longer in use and gma500 has been using
drm_fb_helper_setcmap() for several years without issues.

Fixes: 3da6c2f3b730 ("drm/gma500: use DRM_FB_HELPER_DEFAULT_OPS for fb_ops")
Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Cc: Stefan Christ <contact@stefanchrist.eu>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v4.10+
Link: https://elixir.bootlin.com/linux/v6.16.9/source/drivers/video/fbdev/core/fbcmap.c#L246 # [1]
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Link: https://lore.kernel.org/r/20250929082338.18845-1-tzimmermann@suse.de

diff --git a/drivers/gpu/drm/gma500/fbdev.c b/drivers/gpu/drm/gma500/fbdev.c
index 32d31e5f5f1a..a6af21514cff 100644
--- a/drivers/gpu/drm/gma500/fbdev.c
+++ b/drivers/gpu/drm/gma500/fbdev.c
@@ -50,48 +50,6 @@ static const struct vm_operations_struct psb_fbdev_vm_ops = {
  * struct fb_ops
  */
 
-#define CMAP_TOHW(_val, _width) ((((_val) << (_width)) + 0x7FFF - (_val)) >> 16)
-
-static int psb_fbdev_fb_setcolreg(unsigned int regno,
-				  unsigned int red, unsigned int green,
-				  unsigned int blue, unsigned int transp,
-				  struct fb_info *info)
-{
-	struct drm_fb_helper *fb_helper = info->par;
-	struct drm_framebuffer *fb = fb_helper->fb;
-	uint32_t v;
-
-	if (!fb)
-		return -ENOMEM;
-
-	if (regno > 255)
-		return 1;
-
-	red = CMAP_TOHW(red, info->var.red.length);
-	blue = CMAP_TOHW(blue, info->var.blue.length);
-	green = CMAP_TOHW(green, info->var.green.length);
-	transp = CMAP_TOHW(transp, info->var.transp.length);
-
-	v = (red << info->var.red.offset) |
-	    (green << info->var.green.offset) |
-	    (blue << info->var.blue.offset) |
-	    (transp << info->var.transp.offset);
-
-	if (regno < 16) {
-		switch (fb->format->cpp[0] * 8) {
-		case 16:
-			((uint32_t *) info->pseudo_palette)[regno] = v;
-			break;
-		case 24:
-		case 32:
-			((uint32_t *) info->pseudo_palette)[regno] = v;
-			break;
-		}
-	}
-
-	return 0;
-}
-
 static int psb_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 {
 	if (vma->vm_pgoff != 0)
@@ -135,7 +93,6 @@ static const struct fb_ops psb_fbdev_fb_ops = {
 	.owner = THIS_MODULE,
 	__FB_DEFAULT_IOMEM_OPS_RDWR,
 	DRM_FB_HELPER_DEFAULT_OPS,
-	.fb_setcolreg = psb_fbdev_fb_setcolreg,
 	__FB_DEFAULT_IOMEM_OPS_DRAW,
 	.fb_mmap = psb_fbdev_fb_mmap,
 	.fb_destroy = psb_fbdev_fb_destroy,