media: dvb-usb: dibusb-mb: use an enum for the device number

The device number is currently a value that needs to be the same
on two separate tables, but the code doesn't actually enforce it,
leading to errors as boards get added or removed.

Fix it by using an enum.

Link: https://lore.kernel.org/linux-media/a300c26ad4e9bb913e86eeaf0ec7d72b9e7d5d3e.1648499509.git.mchehab@kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

media: dvb: return -EREMOTEIO on i2c transfer failure.

Currently when i2c transfers fail the error return -EREMOTEIO
is assigned to err but then later overwritten when the tuner
attach call is made. Fix this by returning early with the
error return code -EREMOTEIO on i2c transfer failure errors.

If the transfer fails, an uninitialized value will be read from b2.

Addresses-Coverity: ("Unused value")

Fixes: fbfee8684ff2 ("V4L/DVB (5651): Dibusb-mb: convert pll handling to properly use dvb-pll")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: docs: move driver-specific info to driver-api

Those documents don't really describe the driver API.

Instead, they contain development-specific information.

Yet, as the main index file describes the content of it as:

"how specific kernel subsystems work
from the point of view of a kernel developer"

It seems to be the better fit.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 468

Based on 1 normalized pattern(s):

based on gpl code from [dibcom] which has [copyright] [c] [2004]
[amaury] [demol] [for] [dibcom] 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
version 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081202.886876323@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

media: dvb: point to the location of the old README.dvb-usb file

This file got renamed, but the references still point to the
old place.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>

[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] 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>