media: usb: uvc: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: uvcvideo: drop error check of debugfs_create_dir()

No need check the return value of debugfs_create_dir()

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1573541519-28488-1-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

media: uvcvideo: Include streaming interface number in debugfs dir name

uvcvideo creates a debugfs directory based on the device bus number and
device number. If a device contains more than one uvc function, the
creation of the second and following debugfs directories will fail and
print an info message like this:
"uvcvideo: Unable to create debugfs 3-2 directory."

This patch includes the uvc streaming interface number in the debugfs
directory name, to make sure it is unique. The directory name format is
changed from "<busnum>-<devnum>" to "<busnum>-<devnum>-<intfnum>"

Signed-off-by: Torleiv Sundre <torleiv@huddly.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

media: uvcvideo: Remove unnecessary NULL check before debugfs_remove_recursive

debugfs_remove_recursive() accepts a NULL parameter and returns
immediately, there's no need for a NULL check in the caller.

This issue was detected with the help of Coccinelle.

[Reword commit message, address uvc_debugfs_cleanup_stream()]

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

[media] uvcvideo: Change result code of debugfs_init to void

The device driver should keep going even if debugfs initialization fails.
So, change the return type to void.

Signed-off-by: Jaejoong Kim <climbbb.kim@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

[media] rename most media/video usb drivers to media/usb

Rename all USB drivers with their own directory under
drivers/media/video into drivers/media/usb and update the
building system.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>