Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted

Pull media updates from Mauro Carvalho Chehab:

 - v4l2-core: added ISP statistics support and per-block validation

 - v4l2-core: Allow unknown HDR10 white point and luminance

 - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor

 - New codec: Milos: VPU v2.0 codec support

 - isp driver: gained support for Dreamchip RPPX1 ISP framework

 - vsp1 driver: gained support for RZ/T2H and RZ/N2H

 - Novalake driver: gained CVS support for new NVL hardware

 - dvb-core: fix feed leak on failed DMX_ADD_PID

 - several driver fixes, cleanups and minor improvements

* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
  media: ipu-bridge: check all DMI entries when overriding sensor rotation
  media: v4l2-async: avoid deleting unlinked ASC entry on link error
  media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
  media: intel/ipu6: fix async notifier cleanup leak on parse error
  media: staging/ipu7: fix async notifier UAF on probe error path
  media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
  media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
  media: rcar-isp: Fix VSPX reference leaks
  media: rcar-isp: Release ISPCORE resources
  media: i2c: imx415: Release runtime PM reference on VBLANK error
  media: i2c: imx415: Return test pattern write errors
  media: renesas: vsp1: Declare index variables in for loop statement
  media: renesas: vsp1: Make reset control optional to support platforms without a reset line
  media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
  media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
  media: nxp: imx8-isi: Add additional 32-bit RGB format support
  media: nxp: imx8-isi: Add 16-bit raw Bayer format support
  media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
  media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
  media: nxp: imx8-isi: Correct color map between V4L2 and ISI
  ...

1 files changed, 147 insertions, 0 deletions

diff --git a/Documentation/admin-guide/serial-console.rst b/Documentation/admin-guide/serial-console.rst
new file mode 100644
index 000000000..1609e7479
--- /dev/null
+++ b/Documentation/admin-guide/serial-console.rst
@@ -0,0 +1,147 @@
+.. _serial_console:
+
+Linux Serial Console
+====================
+
+To use a serial port as console you need to compile the support into your
+kernel - by default it is not compiled in. For PC style serial ports
+it's the config option next to menu option:
+
+:menuselection:`Character devices --> Serial drivers --> 8250/16550 and compatible serial support --> Console on 8250/16550 and compatible serial port`
+
+You must compile serial support into the kernel and not as a module.
+
+It is possible to specify multiple devices for console output. You can
+define a new kernel command line option to select which device(s) to
+use for console output.
+
+The format of this option is::
+
+	console=device,options
+
+	device:		tty0 for the foreground virtual console
+			ttyX for any other virtual console
+			ttySx for a serial port
+			lp0 for the first parallel port
+			ttyUSB0 for the first USB serial device
+
+	options:	depend on the driver. For the serial port this
+			defines the baudrate/parity/bits/flow control of
+			the port, in the format BBBBPNF, where BBBB is the
+			speed, P is parity (n/o/e), N is number of bits,
+			and F is flow control ('r' for RTS). Default is
+			9600n8. The maximum baudrate is 115200.
+
+You can specify multiple console= options on the kernel command line.
+
+The behavior is well defined when each device type is mentioned only once.
+In this case, the output will appear on all requested consoles. And
+the last device will be used when you open ``/dev/console``.
+So, for example::
+
+	console=ttyS1,9600 console=tty0
+
+defines that opening ``/dev/console`` will get you the current foreground
+virtual console, and kernel messages will appear on both the VGA
+console and the 2nd serial port (ttyS1 or COM2) at 9600 baud.
+
+The behavior is more complicated when the same device type is defined more
+times. In this case, there are the following two rules:
+
+1. The output will appear only on the first device of each defined type.
+
+2. ``/dev/console`` will be associated with the first registered device.
+   Where the registration order depends on how kernel initializes various
+   subsystems.
+
+   This rule is used also when the last console= parameter is not used
+   for other reasons. For example, because of a typo or because
+   the hardware is not available.
+
+The result might be surprising. For example, the following two command
+lines have the same result::
+
+	console=ttyS1,9600 console=tty0 console=tty1
+	console=tty0 console=ttyS1,9600 console=tty1
+
+The kernel messages are printed only on ``tty0`` and ``ttyS1``. And
+``/dev/console`` gets associated with ``tty0``. It is because kernel
+tries to register graphical consoles before serial ones. It does it
+because of the default behavior when no console device is specified,
+see below.
+
+Note that the last ``console=tty1`` parameter still makes a difference.
+The kernel command line is used also by systemd. It would use the last
+defined ``tty1`` as the login console.
+
+If no console device is specified, the first device found capable of
+acting as a system console will be used. At this time, the system
+first looks for a VGA card and then for a serial port. So if you don't
+have a VGA card in your system the first serial port will automatically
+become the console, unless the kernel is configured with the
+CONFIG_NULL_TTY_DEFAULT_CONSOLE option, then it will default to using the
+ttynull device.
+
+You will need to create a new device to use ``/dev/console``. The official
+``/dev/console`` is now character device 5,1.
+
+(You can also use a network device as a console.  See
+``Documentation/networking/netconsole.rst`` for information on that.)
+
+Here's an example that will use ``/dev/ttyS1`` (COM2) as the console.
+Replace the sample values as needed.
+
+1. Create ``/dev/console`` (real console) and ``/dev/tty0`` (master virtual
+   console)::
+
+     cd /dev
+     rm -f console tty0
+     mknod -m 622 console c 5 1
+     mknod -m 622 tty0 c 4 0
+
+2. LILO can also take input from a serial device. This is a very
+   useful option. To tell LILO to use the serial port:
+   In lilo.conf (global section)::
+
+     serial  = 1,9600n8 (ttyS1, 9600 bd, no parity, 8 bits)
+
+3. Adjust to kernel flags for the new kernel,
+   again in lilo.conf (kernel section)::
+
+     append = "console=ttyS1,9600"
+
+4. Make sure a getty runs on the serial port so that you can login to
+   it once the system is done booting. This is done by adding a line
+   like this to ``/etc/inittab`` (exact syntax depends on your getty)::
+
+     S1:23:respawn:/sbin/getty -L ttyS1 9600 vt100
+
+5. Init and ``/etc/ioctl.save``
+
+   Sysvinit remembers its stty settings in a file in ``/etc``, called
+   ``/etc/ioctl.save``. REMOVE THIS FILE before using the serial
+   console for the first time, because otherwise init will probably
+   set the baudrate to 38400 (baudrate of the virtual console).
+
+6. ``/dev/console`` and X
+   Programs that want to do something with the virtual console usually
+   open ``/dev/console``. If you have created the new ``/dev/console`` device,
+   and your console is NOT the virtual console some programs will fail.
+   Those are programs that want to access the VT interface, and use
+   ``/dev/console instead of /dev/tty0``. Some of those programs are::
+
+     Xfree86, svgalib, gpm, SVGATextMode
+
+   It should be fixed in modern versions of these programs though.
+
+   Note that if you boot without a ``console=`` option (or with
+   ``console=/dev/tty0``), ``/dev/console`` is the same as ``/dev/tty0``.
+   In that case everything will still work.
+
+7. Thanks
+
+   Thanks to Geert Uytterhoeven <geert@linux-m68k.org>
+   for porting the patches from 2.1.4x to 2.1.6x for taking care of
+   the integration of these patches into m68k, ppc and alpha.
+
+Miquel van Smoorenburg <miquels@cistron.nl>, 11-Jun-2000