Detect registered instances of fb_info by reading the reference counter from struct fb_info.read. Avoids looking at the dev field and prepares fbdev for making struct fb_info.dev optional.
Signed-off-by: Thomas Zimmermann <tzimmerm...@suse.de> Cc: Steve Glendinning <steve.glendinn...@shawell.net> --- drivers/video/fbdev/smscufx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/video/fbdev/smscufx.c b/drivers/video/fbdev/smscufx.c index 17cec62cc65d..adb2b1fe8383 100644 --- a/drivers/video/fbdev/smscufx.c +++ b/drivers/video/fbdev/smscufx.c @@ -1496,7 +1496,7 @@ static int ufx_setup_modes(struct ufx_data *dev, struct fb_info *info, u8 *edid; int i, result = 0, tries = 3; - if (info->dev) /* only use mutex if info has been registered */ + if (refcount_read(&info->count)) /* only use mutex if info has been registered */ mutex_lock(&info->lock); edid = kmalloc(EDID_LENGTH, GFP_KERNEL); @@ -1610,7 +1610,7 @@ static int ufx_setup_modes(struct ufx_data *dev, struct fb_info *info, if (edid && (dev->edid != edid)) kfree(edid); - if (info->dev) + if (refcount_read(&info->count)) mutex_unlock(&info->lock); return result; -- 2.40.1