media: uvcvideo: Handle cameras with invalid descriptors

If the source entity does not contain any pads, do not create a link.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

media: uvcvideo: Use dev_ printk aliases

Replace all the uses of printk() and uvc_printk() with its
equivalent dev_ alias macros.

Modify uvc_warn_once() macro to use dev_info instead printk().

They are more standard across the kernel tree and provide
more context about the error.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: uvcvideo: Implement UVC_EXT_GPIO_UNIT

Some devices can implement a physical switch to disable the input of the
camera on demand. Think of it like an elegant privacy sticker.

The system can read the status of the privacy switch via a GPIO.

It is important to know the status of the switch, e.g. to notify the
user when the camera will produce black frames and a videochat
application is used.

In some systems, the GPIO is connected to the main SoC instead of the
camera controller, with the connection reported by the system firmware
(ACPI or DT). In that case, the UVC device isn't aware of the GPIO. We
need to implement a virtual entity to handle the GPIO fully on the
driver side.

For example, for ACPI-based systems, the GPIO is reported in the USB
device object:

Scope (\_SB.PCI0.XHCI.RHUB.HS07)
{

/.../

Name (_CRS, ResourceTemplate () // _CRS: Current Resource Settings
{
GpioIo (Exclusive, PullDefault, 0x0000, 0x0000, IoRestrictionOutputOnly,
"\\_SB.PCI0.GPIO", 0x00, ResourceConsumer, ,
)
{ // Pin list
0x0064
}
})
Name (_DSD, Package (0x02) // _DSD: Device-Specific Data
{
ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301") /* Device Properties for _DSD */,
Package (0x01)
{
Package (0x02)
{
"privacy-gpio",
Package (0x04)
{
\_SB.PCI0.XHCI.RHUB.HS07,
Zero,
Zero,
One
}
}
}
})
}

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: uvcvideo: Set media controller entity functions

The media controller core prints a warning when an entity is registered
without a function being set. This affects the uvcvideo driver, as the
warning was added without first addressing the issue in existing
drivers. The problem is harmless, but unnecessarily worries users. Fix
it by mapping UVC entity types to MC entity functions as accurately as
possible using the existing functions.

Fixes: b50bde4e476d ("[media] v4l2-subdev: use MEDIA_ENT_T_UNKNOWN for new subdevs")
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@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: use strscpy() instead of strlcpy()

The implementation of strscpy() is more robust and safer.

That's now the recommended way to copy NUL terminated strings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

media: uvcvideo: Constify video_subdev structures

uvc_subdev_ops is only passed as the second argument of
v4l2_subdev_init, which is const, so uvc_subdev_ops can be
const as well.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

[media] uvcvideo: register entity subdev on init

The uvc_mc_register_entities() function iterated over the entities three
times to initialize the entities, register the subdev for the ones whose
type was UVC_TT_STREAMING and to create the entities links.

But this can be simplied by merging the init and registration logic in a
single loop.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] uvcvideo: remove pads prefix from uvc_mc_create_pads_links()

The function uvc_mc_create_pads_links() creates entities links but the
"pads" prefix is redundant since the driver doesn't handle any other
kind of link, so it can be removed.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] media framework: rename pads init function to media_entity_pads_init()

With the MC next gen rework, what's left for media_entity_init()
is to just initialize the PADs. However, certain devices, like
a FLASH led/light doesn't have any input or output PAD.

So, there's no reason why calling media_entity_init() would be
mandatory. Also, despite its name, what this function actually
does is to initialize the PADs data. So, rename it to
media_entity_pads_init() in order to reflect that.

The media entity actual init happens during entity register,
at media_device_register_entity(). We should move init of
num_links and num_backlinks to it.

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

[media] uvcvideo: create pad links after subdev registration

The uvc driver creates the pads links before the media entity is
registered with the media device. This doesn't work now that obj
IDs are used to create links so the media_device has to be set.

Move entities registration logic before pads links creation.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] media: rename the function that create pad links

With the new API, a link can be either between two PADs or between an interface
and an entity. So, we need to use a better name for the function that create
links between two pads.

So, rename the such function to media_create_pad_link().

No functional changes.

This patch was created via this shell script:
for i in $(find drivers/media -name '*.[ch]' -type f) $(find drivers/staging/media -name '*.[ch]' -type f) $(find include/ -name '*.h' -type f) ; do sed s,media_entity_create_link,media_create_pad_link,g <$i >a && mv a $i; done

Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] media: get rid of unused "extra_links" param on media_entity_init()

Currently, media_entity_init() creates an array with the links,
allocated at init time. It provides a parameter (extra_links)
that would allocate more links than the current needs, but this
is not used by any driver.

As we want to be able to do dynamic link allocation/removal,
we'll need to change the implementation of the links. So,
before doing that, let's first remove that extra unused
parameter, in order to cleanup the interface first.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

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

[media] uvcvideo: Mark first output terminal as default video node

The MEDIA_ENT_FL_DEFAULT identifies entities that are considered as
default for their group and type. For video nodes, it identifies the
node that application should use by default.
UVC devices don't report which output terminal should be considered as
the default, use the first one. Most devices have a single output
terminal anyway.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.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>