[PATCH v2] fbdev: sh_mobile_lcdcfb: Restore the per-overlay sysfs attributes
From: Karl Mehltretter <hidden>
Date: 2026-09-12 10:22:03
Also in:
dri-devel, stable
Subsystem:
framebuffer layer, the rest · Maintainers:
Helge Deller, Linus Torvalds
The ovl_* files documented in
Documentation/ABI/testing/sysfs-devices-platform-sh_mobile_lcdc_fb no
longer exist.
Commit a979182a2453 ("fbdev: lcdcfb: Register sysfs groups through driver
core") moved the attributes from each overlay's framebuffer device to
the platform driver's dev_groups and renamed them overlay_*. There is
now only one set of attributes for the whole LCDC. The callbacks still
expect dev_get_drvdata() to return a struct fb_info, but the platform
device holds struct sh_mobile_lcdc_priv, so they access the wrong
structure.
Restore the documented names and register the group on each overlay's
framebuffer device with device_add_groups(). Remove it with
device_remove_groups() before unregistering the framebuffer. Skip
creation when dev_of_fbinfo(info) is NULL, as the old device_create_file()
calls did.
Drop the CONFIG_FB_DEVICE guard, since the driver already depends on it.
Fixes: a979182a2453 ("fbdev: lcdcfb: Register sysfs groups through driver core")
Cc: stable@vger.kernel.org
Assisted-by: LLM
Signed-off-by: Karl Mehltretter <redacted>
---
Changes in v2:
- Use dev_of_fbinfo() for overlay sysfs registration and removal (Helge).
v1: https://lore.kernel.org/r/20260907021844.25497-1-kmehltretter@gmail.com/ (local)
Found while reviewing the sysfs ABI documentation. Shixiong confirmed
that using the platform driver's dev_groups is wrong here.
Compile-tested with Clang 22.1.8, ARCH=arm and W=1, using multi_v7_defconfig
with COMPILE_TEST=y, FB_DEVICE=y and FB_SH_MOBILE_LCDC=m.
Also checked FB_DEVICE=n: olddefconfig disables FB_SH_MOBILE_LCDC because
of its existing Kconfig dependency, and the framebuffer core compiles.
This does not test the driver with FB_DEVICE=n; removing that dependency
requires additional changes outside the overlay sysfs paths.
No runtime test; I have no SH-Mobile hardware.
drivers/video/fbdev/sh_mobile_lcdcfb.c | 39 +++++++++++++++++---------
1 file changed, 25 insertions(+), 14 deletions(-)
diff --git a/drivers/video/fbdev/sh_mobile_lcdcfb.c b/drivers/video/fbdev/sh_mobile_lcdcfb.c
index e8324b01700f..5743c96d5481 100644
--- a/drivers/video/fbdev/sh_mobile_lcdcfb.c
+++ b/drivers/video/fbdev/sh_mobile_lcdcfb.c@@ -1337,22 +1337,24 @@ overlay_rop3_store(struct device *dev, struct device_attribute *attr, return count; } -static DEVICE_ATTR_RW(overlay_alpha); -static DEVICE_ATTR_RW(overlay_mode); -static DEVICE_ATTR_RW(overlay_position); -static DEVICE_ATTR_RW(overlay_rop3); - -static struct attribute *overlay_sysfs_attrs[] __maybe_unused = { - &dev_attr_overlay_alpha.attr, - &dev_attr_overlay_mode.attr, - &dev_attr_overlay_position.attr, - &dev_attr_overlay_rop3.attr, +static struct device_attribute dev_attr_ovl_alpha = + __ATTR(ovl_alpha, 0644, overlay_alpha_show, overlay_alpha_store); +static struct device_attribute dev_attr_ovl_mode = + __ATTR(ovl_mode, 0644, overlay_mode_show, overlay_mode_store); +static struct device_attribute dev_attr_ovl_position = + __ATTR(ovl_position, 0644, overlay_position_show, overlay_position_store); +static struct device_attribute dev_attr_ovl_rop3 = + __ATTR(ovl_rop3, 0644, overlay_rop3_show, overlay_rop3_store); + +static struct attribute *overlay_sysfs_attrs[] = { + &dev_attr_ovl_alpha.attr, + &dev_attr_ovl_mode.attr, + &dev_attr_ovl_position.attr, + &dev_attr_ovl_rop3.attr, NULL, }; -#ifdef CONFIG_FB_DEVICE ATTRIBUTE_GROUPS(overlay_sysfs); -#endif static const struct fb_fix_screeninfo sh_mobile_lcdc_overlay_fix = { .id = "SH Mobile LCDC",
@@ -1510,9 +1512,10 @@ sh_mobile_lcdc_overlay_fb_unregister(struct sh_mobile_lcdc_overlay *ovl) { struct fb_info *info = ovl->info; - if (info == NULL || info->dev == NULL) + if (!info || !dev_of_fbinfo(info)) return; + device_remove_groups(dev_of_fbinfo(info), overlay_sysfs_groups); unregister_framebuffer(ovl->info); }
@@ -1530,6 +1533,15 @@ sh_mobile_lcdc_overlay_fb_register(struct sh_mobile_lcdc_overlay *ovl) if (ret < 0) return ret; + /* The framebuffer device is optional, see fb_device_create(). */ + if (dev_of_fbinfo(info)) { + ret = device_add_groups(dev_of_fbinfo(info), overlay_sysfs_groups); + if (ret < 0) { + unregister_framebuffer(info); + return ret; + } + } + dev_info(lcdc->dev, "registered %s/overlay %u as %dx%d %dbpp.\n", dev_name(lcdc->dev), ovl->index, info->var.xres, info->var.yres, info->var.bits_per_pixel);
@@ -2637,7 +2649,6 @@ static int sh_mobile_lcdc_probe(struct platform_device *pdev) static struct platform_driver sh_mobile_lcdc_driver = { .driver = { .name = "sh_mobile_lcdc_fb", - .dev_groups = overlay_sysfs_groups, .pm = &sh_mobile_lcdc_dev_pm_ops, }, .probe = sh_mobile_lcdc_probe,
base-commit: 986c24e0fe44f844b44d365b71ce831947f50298 -- 2.39.5 (Apple Git-154)