media: cxusb: implement Medion MD95700 digital / analog coexistence

This patch prepares cxusb driver for supporting the analog part of
Medion 95700 (previously only the digital - DVB - mode was supported).

Specifically, it adds support for:
* switching the device between analog and digital modes of operation,
* enforcing that only one mode is active at the same time due to hardware
limitations.

Actual implementation of the analog mode will be provided by the next
commit.

Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

media: dvbdev: add a mutex protecting the "mdev" pointer

During destruction, a race condition in
dvb_media_controller_disable_source() can cause a kernel crash,
because the "mdev" pointer has been read successfully while another
task executes dvb_usb_media_device_unregister(), which destroys the
object. Example for such a crash:

general protection fault: 0000 [#1] SMP
CPU: 1 PID: 301 Comm: vdr Not tainted 4.8.1-nuc+ #102
[142B blob data]
task: ffff8802301f2040 task.stack: ffff880233728000
RIP: 0010:[<ffffffff816c296b>] [<ffffffff816c296b>] dvb_frontend_release+0xcb/0x120
RSP: 0018:ffff88023372bdd8 EFLAGS: 00010202
RAX: 001fd55c000000da RBX: ffff880236bad810 RCX: 0000000000000000
RDX: ffff880235bd81f0 RSI: 0000000000000246 RDI: ffff880235bd81e8
RBP: ffff88023372be00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffff88022f009910 R12: 0000000000000000
R13: ffff880235a21a80 R14: ffff880235bd8000 R15: ffff880235bb8a78
FS: 0000000000000000(0000) GS:ffff88023fd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f96edd69818 CR3: 0000000002406000 CR4: 00000000001006e0
Stack:
ffff88022f009900 0000000000000008 ffff880235bb8a78 ffff8802344fbb20
ffff880236437b40 ffff88023372be48 ffffffff8117a81e ffff880235bb8a78
ffff88022f009910 ffff8802335a7400 ffff8802301f2040 ffff88022f009900
Call Trace:
[<ffffffff8117a81e>] __fput+0xde/0x1d0
[<ffffffff8117a949>] ____fput+0x9/0x10
[<ffffffff810a9fce>] task_work_run+0x7e/0xa0
[<ffffffff81094bab>] do_exit+0x27b/0xa50
[<ffffffff810407e3>] ? __do_page_fault+0x1c3/0x430
[<ffffffff81095402>] do_group_exit+0x42/0xb0
[<ffffffff8109547f>] SyS_exit_group+0xf/0x10
[<ffffffff8108bedb>] entry_SYSCALL_64_fastpath+0x13/0x8f
Code: 31 c9 49 8d be e8 01 00 00 ba 01 00 00 00 be 03 00 00 00 e8 68 2d a0 ff 48 8b 83 10 03 00 00 48 8b 80 88 00 00 00 48 85 c0 74 12 <48> 8b 80 88 02 00 00 48 85 c0 74 06 49 8b 7d
RIP [<ffffffff816c296b>] dvb_frontend_release+0xcb/0x120

[mchehab+samsung@kernel.org: fix a Coding Style issue]
Signed-off-by: Max Kellermann <max.kellermann@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[media] dvb-usb: don't break long lines

Due to the 80-cols restrictions, and latter due to checkpatch
warnings, several strings were broken into multiple lines. This
is not considered a good practice anymore, as it makes harder
to grep for strings at the source code.

As we're right now fixing other drivers due to KERN_CONT, we need
to be able to identify what printk strings don't end with a "\n".
It is a way easier to detect those if we don't break long lines.

So, join those continuation lines.

The patch was generated via the script below, and manually
adjusted if needed.

</script>
use Text::Tabs;
while (<>) {
if ($next ne "") {
$c=$_;
if ($c =~ /^\s+\"(.*)/) {
$c2=$1;
$next =~ s/\"\n$//;
$n = expand($next);
$funpos = index($n, '(');
$pos = index($c2, '",');
if ($funpos && $pos > 0) {
$s1 = substr $c2, 0, $pos + 2;
$s2 = ' ' x ($funpos + 1) . substr $c2, $pos + 2;
$s2 =~ s/^\s+//;

$s2 = ' ' x ($funpos + 1) . $s2 if ($s2 ne "");

print unexpand("$next$s1\n");
print unexpand("$s2\n") if ($s2 ne "");
} else {
print "$next$c2\n";
}
$next="";
next;
} else {
print $next;
}
$next="";
} else {
if (m/\"$/) {
if (!m/\\n\"$/) {
$next=$_;
next;
}
}
}
print $_;
}
</script>

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

[media] dvb-usb: silence an uninitialized variable warning

My static checker complains that if adap->props.num_frontends is 0 then
"ret" is uninitialized. I don't think that can happen. But "ret" is
always zero here so we can just remove the condition.

This extra check was added in commit 0d3ab8410dcb ('[media] dvb core:
must check dvb_create_media_graph()').

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

[media] media_device: move allocation out of media_device_*_init

Right now, media_device_pci_init and media_device_usb_init does
media_device allocation internaly. That preents its usage when
the media_device struct is embedded on some other structure.

Move memory allocation outside it, to make it more generic.

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

[media] media-device: move PCI/USB helper functions from v4l2-mc

Those ancillary functions could be called even when compiled
without V4L2 support, as warned by ktest build robot:

All errors (new ones prefixed by >>):

>> ERROR: "__v4l2_mc_usb_media_device_init" [drivers/media/usb/dvb-usb/dvb-usb.ko] undefined!
>> ERROR: "__v4l2_mc_usb_media_device_init" [drivers/media/usb/dvb-usb-v2/dvb_usb_v2.ko] undefined!
>> ERROR: "__v4l2_mc_usb_media_device_init" [drivers/media/usb/au0828/au0828.ko] undefined!

Also, there's nothing there that are specific to V4L2. So, move
those ancillary functions to MC core.

No functional changes. Just function rename.

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

[media] use v4l2_mc_usb_media_device_init() on most USB devices

Except for the usbuvc driver (with has an embedded media_device
struct on it), the other drivers have a pointer to media_device.

On those drivers, replace their own implementation for the core
one. That warrants that those subdev drivers will fill the
media_device info the same way.

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

[media] media: change email address

Soon my dibcom.fr/parrot.com-address won't respond anymore.
Thus I'm replacing it. And, while being at it,
let's adapt some other (old) email-addresses as well.

Signed-off-by: Patrick Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] dvbdev: Add RF connector if needed

Several pure digital TV devices have a frontend with the tuner
integrated on it. Add the RF connector when dvb_create_media_graph()
is called on such devices.

Tested with siano and dvb_usb_mxl111sf drivers.

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

[media] usb: check media device errors

There are now two new warnings:

drivers/media/usb/dvb-usb-v2/dvb_usb_core.c: In function 'dvb_usbv2_media_device_register':
drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:433:2: warning: ignoring return value of '__media_device_register', declared with attribute warn_unused_result [-Wunused-result]
media_device_register(adap->dvb_adap.mdev);
^
drivers/media/usb/dvb-usb/dvb-usb-dvb.c: In function 'dvb_usb_media_device_register':
drivers/media/usb/dvb-usb/dvb-usb-dvb.c:128:2: warning: ignoring return value of '__media_device_register', declared with attribute warn_unused_result [-Wunused-result]
media_device_register(adap->dvb_adap.mdev);
^

Those are because the drivers are not properly checking if the
media device init and register were succeeded.

Fix it.

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

[media] media-device: split media initialization and registration

The media device node is registered and so made visible to user-space
before entities are registered and links created which means that the
media graph obtained by user-space could be only partially enumerated
if that happens too early before all the graph has been created.

To avoid this race condition, split the media init and registration
in separate functions and only register the media device node when
all the pending subdevices have been registered, either explicitly
by the driver or asynchronously using v4l2_async_register_subdev().

The media_device_register() had a check for drivers not filling dev
and model fields but all drivers in mainline set them and not doing
it will be a driver bug so change the function return to void and
add a BUG_ON() for dev being NULL instead.

Also, add a media_device_cleanup() function that will destroy the
graph_mutex that is initialized in media_device_init().

[mchehab@osg.samsung.com: Fix compilation if !CONFIG_MEDIA_CONTROLLER
and remove two warnings added by this changeset]
Suggested-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] dvb core: must check dvb_create_media_graph()

If media controller is enabled and mdev is filled, it should
ensure that the media graph will be properly initialized.

Enforce that.

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

[media] dvb-usb: fix spaces after commas

Fixing a few checkpatch errors of type: space required after that ','

Signed-off-by: Luis de Bethencourt <luis.bg@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] use a function for DVB media controller register

This is really a simple function, but using it avoids to have
if's inside the drivers.

Also, the kABI becomes a little more clearer.

This shouldn't generate any overhead, and the type check
will happen when compiling with MC DVB enabled.

So, let's do it.

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

[media] dvb: Avoid warnings when compiled without the media controller

drivers/media/usb/dvb-usb-v2/dvb_usb_core.c: In function ‘dvb_usbv2_adapter_dvb_exit’:
drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:531:25: warning: unused variable ‘d’ [-Wunused-variable]
struct dvb_usb_device *d = adap_to_d(adap);
^
drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:403:13: warning: ‘dvb_usbv2_media_device_register’ defined but not used [-Wunused-function]
static void dvb_usbv2_media_device_register(struct dvb_usb_adapter *adap)

drivers/media/usb/dvb-usb/dvb-usb-dvb.c:97:13: warning: ‘dvb_usb_media_device_register’ defined but not used [-Wunused-function]
static void dvb_usb_media_device_register(struct dvb_usb_adapter *adap)
^

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

[media] dvbdev: use adapter arg for dvb_create_media_graph()

Instead of using media_dev argument for dvb_create_media_graph(),
use the adapter.

That allows to create a stub for this function, if compiled
without DVB support, avoiding to add extra if's at the drivers.

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

[media] dvb-usb: create one media_dev per adapter

Instead of assuming just one adapter, change the code to store
one media controller per adapter.

This works fine for dvb-usb, as, on all drivers here, it is not
possible to write a media graph that would mix resources between
the two different adapters.

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

[media] dvb-usb: add support for the media controller at USB driver

Create a struct media_device and add it to the dvb adapter.

Please notice that the tuner is not mapped yet by the dvb core.

[mchehab@osg.samsung.com: use config option MEDIA_CONTROLLER_DVB]
Signed-off-by: Rafael Lourenço de Lima Chehab <chehabrafael@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

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

[media] dvb-usb: move it to drivers/media/usb/dvb-usb

As media/dvb will be removed, move it to a proper place.

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