usb: gadget: webcam: Make g_webcam loadable again

commit 588b9e85609b ("usb: gadget: uvc: add v4l2 enumeration api calls")
has rendered the precomposed (aka legacy) webcam gadget unloadable.

uvc_alloc() since then has depended on certain config groups being
available in configfs tree related to the UVC function. However, legacy
gadgets do not create anything in configfs, so uvc_alloc() must fail
with -ENOENT no matter what.

This patch mimics the required configfs hierarchy to satisfy the code which
inspects formats and frames found in uvcg_streaming_header.

This has been tested with guvcview on the host side, using vivid as a
source of video stream on the device side and using the userspace program
found at https://gitlab.freedesktop.org/camera/uvc-gadget.git.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Fixes: 588b9e85609b ("usb: gadget: uvc: add v4l2 enumeration api calls")
Link: https://lore.kernel.org/r/20231215131614.29132-1-andrzej.p@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: g_webcam: Send color matching descriptor per frame

Currently the color matching descriptor is only sent across the wire
a single time, following the descriptors for each format and frame.
According to the UVC 1.5 Specification 3.9.2.6 ("Color Matching
Descriptors"):

"Only one instance is allowed for a given format and if present,
the Color Matching descriptor shall be placed following the Video
and Still Image Frame descriptors for that format".

Add another reference to the color matching descriptor after the
yuyv frames so that it's correctly transmitted for that format
too.

Fixes: a9914127e834 ("USB gadget: Webcam device")
Cc: stable <stable@kernel.org>
Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Link: https://lore.kernel.org/r/20221216160528.479094-1-dan.scally@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: uvc: Rename bmInterfaceFlags -> bmInterlaceFlags

In the specification documents for the Uncompressed and MJPEG USB
Video Payloads, the field name is bmInterlaceFlags - it has been
misnamed within the kernel.

Although renaming the field does break the kernel's interface to
userspace it should be low-risk in this instance. The field is read
only and hardcoded to 0, so there was never any value in anyone
reading it. A search of the uvc-gadget application and all the
forks that I could find for it did not reveal any users either.

Fixes: cdda479f15cd ("USB gadget: video class function driver")
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>
Link: https://lore.kernel.org/r/20221206161203.1562827-1-dan.scally@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: webcam: Invalid size of Processing Unit Descriptor

According with USB Device Class Definition for Video Device the
Processing Unit Descriptor bLength should be 12 (10 + bmControlSize),
but it has 11.

Invalid length caused that Processing Unit Descriptor Test Video form
CV tool failed. To fix this issue patch adds bmVideoStandards into
uvc_processing_unit_descriptor structure.

The bmVideoStandards field was added in UVC 1.1 and it wasn't part of
UVC 1.0a.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Reviewed-by: Peter Chen <peter.chen@kernel.org>
Link: https://lore.kernel.org/r/20210315071748.29706-1-pawell@gli-login.cadence.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: uvc: Updating bcdUVC field to 0x0110

Command Verifier during UVC Descriptor Tests (Class Video Control
Interface Descriptor Test Video) complains about:

Video Control Interface Header bcdUVC is 0x0100. USB Video Class
specification 1.0 has been replaced by 1.1 specification
(UVC: 6.2.26) Class Video Control Interface Descriptor bcdUVC is not 1.1

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Reviewed-by: Peter Chen <peter.chen@kernel.org>
Link: https://lore.kernel.org/r/20210315065926.30152-1-pawell@gli-login.cadence.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: uvc: Move trace parameter to function module

The trace module parameter controls output of debugging messages in the
UVC function driver. Move it from the webcam module to the UVC function
module where it belongs. This allows ConfigFS-based UVC gadgets to
control tracing.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

USB: gadget: legacy: Remove redundant license text

Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner. So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Johan Hovold <johan@kernel.org>
Cc: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Cc: Peter Chen <peter.chen@nxp.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: David Windsor <dwindsor@gmail.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: add SPDX identifiers to all remaining files in drivers/usb/

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: gadget: remove unneeded MODULE_VERSION() usage

MODULE_VERSION is useless for in-kernel drivers, so just remove all
usage of it in the USB gadget drivers. Along with this, some
DRIVER_VERSION macros were removed as they are also pointless.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: composite: remove redundant bcdUSB setting in legacy

Since composite now overwrites bcdUSB for any gadget, remove
setting it in legacy gadgets. All legacy gadgets set 0x0200, the
same as the value additionally set by composite, so there is no
behaviour change.

Signed-off-by: Igor Kotrasinski <i.kotrasinsk@samsung.com>

Rebase onto current balbi/next

Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: gadget: remove incorrect __init/__exit annotations

A recent change introduced a link error for the composite
printer gadget driver:

`printer_unbind' referenced in section `.ref.data' of drivers/built-in.o: defined in discarded section `.exit.text' of drivers/built-in.o

Evidently the unbind function should not be marked __exit here,
because it is called through a callback pointer that is not necessarily
discarded, __composite_unbind() is indeed called from the error path of
composite_bind(), which can never work for a built-in driver.

Looking at the surrounding code, I found the same problem in all other
composite gadget drivers in both the bind and unbind functions, as
well as the udc platform driver 'remove' functions. Those will break
if anyone uses the 'unbind' sysfs attribute to detach a device from a
built-in driver.

This patch removes the incorrect annotations from all the gadget
drivers.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: gadget: webcam: convert webcam to new interface of f_uvc

Use the new function interface of f_uvc.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Tested-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: gadget: f_uvc: convert f_uvc to new function interface

Use the new function registration interface. It is required
in order to integrate configfs support.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Tested-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
[Updated copyright years]
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: gadget: uvc: separately compile some components of f_uvc

Compile uvc_queue, uvc_v4l2, uvc_video separately so that later they can
be all combined in a separately compiled f_uvc.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Tested-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
[Make uvc_v4l2_ioctl_ops non-static]
[Rename __UVC__V4L2__H__ and __UVC__VIDEO__H__]
[Update MAINTAINERS]
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: gadget: uvc: move module parameters from f_uvc

When configfs support is integrated the future uvc function
module must not take any parameters. Move parameters to
webcam.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Tested-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: gadget: Gadget directory cleanup - group legacy gadgets

The drivers/usb/gadget directory contains many files.
Files which are related can be distributed into separate directories.
This patch moves the legacy gadgets (i.e. those not using configfs)
into a separate directory.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>