media: atomisp: remove compat_ioctl32 code

This is one of the last remaining users of compat_alloc_user_space()
and copy_in_user(), which are in the process of getting removed.

As of commit 57e6b6f2 ("media: atomisp_fops.c: disable
atomisp_compat_ioctl32"), nothing in this file is actually getting used
as the only reference has been stubbed out.

Remove the entire file -- anyone willing to restore the functionality
can equally well just look up the contents in the git history if needed.
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/staging/media/atomisp/Makefile

@@ -16,7 +16,6 @@ atomisp-objs += \
 	pci/atomisp_acc.o \
 	pci/atomisp_cmd.o \
 	pci/atomisp_compat_css20.o \
-	pci/atomisp_compat_ioctl32.o \
 	pci/atomisp_csi2.o \
 	pci/atomisp_drvfs.o \
 	pci/atomisp_file.o \

drivers/staging/media/atomisp/TODO

@@ -120,6 +120,11 @@ TODO
     for this driver until the other work is done, as there will be a lot
     of code churn until this driver becomes functional again.
 
+16. Fix private ioctls to not need a compat_ioctl handler for running
+    32-bit tasks. The compat code has been removed because of bugs,
+    and should not be needed for modern drivers. Fixing this properly
+    unfortunately means an incompatible ABI change.
+
 Limitations
 ===========
 

drivers/staging/media/atomisp/pci/atomisp_fops.c

@@ -1283,7 +1283,8 @@ const struct v4l2_file_operations atomisp_fops = {
 	.unlocked_ioctl = video_ioctl2,
 #ifdef CONFIG_COMPAT
 	/*
-	 * There are problems with this code. Disable this for now.
+	 * this was removed because of bugs, the interface
+	 * needs to be made safe for compat tasks instead.
 	.compat_ioctl32 = atomisp_compat_ioctl32,
 	 */
 #endif
@@ -1297,10 +1298,7 @@ const struct v4l2_file_operations atomisp_file_fops = {
 	.mmap = atomisp_file_mmap,
 	.unlocked_ioctl = video_ioctl2,
 #ifdef CONFIG_COMPAT
-	/*
-	 * There are problems with this code. Disable this for now.
-	.compat_ioctl32 = atomisp_compat_ioctl32,
-	 */
+	/* .compat_ioctl32 = atomisp_compat_ioctl32, */
 #endif
 	.poll = atomisp_poll,
 };