From: Thomas Zimmermann Date: Tue, 13 Jun 2023 11:07:05 +0000 (+0200) Subject: fbdev/smscufx: Detect registered fb_info from refcount X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=f5c6291f12090c4a0cdf0832da513c5a3e41d186;p=linux.git fbdev/smscufx: Detect registered fb_info from refcount 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 Cc: Steve Glendinning Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20230613110953.24176-31-tzimmermann@suse.de --- diff --git a/drivers/video/fbdev/smscufx.c b/drivers/video/fbdev/smscufx.c index 17cec62cc65db..adb2b1fe8383c 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 @@ error: if (edid && (dev->edid != edid)) kfree(edid); - if (info->dev) + if (refcount_read(&info->count)) mutex_unlock(&info->lock); return result;