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-rw-r--r--Documentation/driver-api/media/camera-sensor.rst7
-rwxr-xr-xDocumentation/driver-api/media/drivers/ccs/mk-ccs-regs104
-rw-r--r--Documentation/driver-api/media/tx-rx.rst25
-rw-r--r--Documentation/driver-api/media/v4l2-subdev.rst11
4 files changed, 101 insertions, 46 deletions
diff --git a/Documentation/driver-api/media/camera-sensor.rst b/Documentation/driver-api/media/camera-sensor.rst
index 6456145f96ed..b4920b34cebc 100644
--- a/Documentation/driver-api/media/camera-sensor.rst
+++ b/Documentation/driver-api/media/camera-sensor.rst
@@ -9,8 +9,8 @@ This document covers the in-kernel APIs only. For the best practices on
userspace API implementation in camera sensor drivers, please see
:ref:`media_using_camera_sensor_drivers`.
-CSI-2 and parallel (BT.601 and BT.656) busses
----------------------------------------------
+CSI-2, parallel and BT.656 buses
+--------------------------------
Please see :ref:`transmitter-receiver`.
@@ -60,7 +60,8 @@ management over the pipeline.
Camera sensor drivers are responsible for controlling the power state of the
device they otherwise control as well. They shall use runtime PM to manage
power states. Runtime PM shall be enabled at probe time and disabled at remove
-time. Drivers should enable runtime PM autosuspend.
+time. Drivers should enable runtime PM autosuspend. Also see
+:ref:`async sub-device registration <media-registering-async-subdevs>`.
The runtime PM handlers shall handle clocks, regulators, GPIOs, and other
system resources required to power the sensor up and down. For drivers that
diff --git a/Documentation/driver-api/media/drivers/ccs/mk-ccs-regs b/Documentation/driver-api/media/drivers/ccs/mk-ccs-regs
index 2a4edc7e051a..3d3152b45821 100755
--- a/Documentation/driver-api/media/drivers/ccs/mk-ccs-regs
+++ b/Documentation/driver-api/media/drivers/ccs/mk-ccs-regs
@@ -82,14 +82,6 @@ for my $fh ($H, $LH) {
print $fh "/* $license */\n$copyright$note\n";
}
-sub bit_def($) {
- my $bit = shift @_;
-
- return "BIT($bit)" if defined $kernel;
- return "(1U << $bit)" if $bit =~ /^[a-zA-Z0-9_]+$/;
- return "(1U << ($bit))";
-}
-
print $H <<EOF
#ifndef __${uc_header}__
#define __${uc_header}__
@@ -97,23 +89,63 @@ print $H <<EOF
EOF
;
-print $H "#include <linux/bits.h>\n\n" if defined $kernel;
-
print $H <<EOF
-#define CCS_FL_BASE 16
+#include <linux/bits.h>
+
+#include <media/v4l2-cci.h>
+
EOF
- ;
+ if defined $kernel;
+
+print $H "#define CCS_FL_BASE " .
+ (defined $kernel ? "CCI_REG_PRIVATE_SHIFT" : 16) . "\n";
+
+my $flag = -1;
+my $all_flags;
+
+sub bit_def($) {
+ my $bit = shift @_;
+
+ if (defined $kernel) {
+ return "BIT$bit" if $bit =~ /^\(.*\)$/;
+ return "BIT($bit)";
+ }
+ return "(1U << $bit)";
+}
+
+sub flag_str($$) {
+ my ($flag, $check) = @_;
-print $H "#define CCS_FL_16BIT " . bit_def("CCS_FL_BASE") . "\n";
-print $H "#define CCS_FL_32BIT " . bit_def("CCS_FL_BASE + 1") . "\n";
-print $H "#define CCS_FL_FLOAT_IREAL " . bit_def("CCS_FL_BASE + 2") . "\n";
-print $H "#define CCS_FL_IREAL " . bit_def("CCS_FL_BASE + 3") . "\n";
+ $$flag++;
+
+ my $flag_str = !$$flag ? "CCS_FL_BASE" : "(CCS_FL_BASE + $$flag)";
+
+ $flag_str = bit_def($flag_str);
+
+ $$check .= " | " if defined $$check;
+
+ $$check .= $flag_str;
+
+ return $flag_str;
+}
+
+if (! defined $kernel) {
+ print $H "#define CCS_FL_16BIT " . flag_str(\$flag, \$all_flags) . "\n";
+ print $H "#define CCS_FL_32BIT " . flag_str(\$flag, \$all_flags) . "\n";
+}
+
+print $H "#define CCS_FL_FLOAT_IREAL " . flag_str(\$flag, \$all_flags) . "\n";
+print $H "#define CCS_FL_IREAL " . flag_str(\$flag, \$all_flags) . "\n";
+print $H "#define CCS_BUILD_BUG \\
+ BUILD_BUG_ON(~CCI_REG_PRIVATE_MASK & ($all_flags))\n"
+ if defined $kernel;
print $H <<EOF
+
#define CCS_R_ADDR(r) ((r) & 0xffff)
EOF
- ;
+ if ! defined $kernel;
print $A <<EOF
#include <stdint.h>
@@ -189,12 +221,12 @@ sub tabconv($) {
return (join "\n", @l) . "\n";
}
-sub elem_size(@) {
+sub elem_bits(@) {
my @flags = @_;
- return 2 if grep /^16$/, @flags;
- return 4 if grep /^32$/, @flags;
- return 1;
+ return 16 if grep /^16$/, @flags;
+ return 32 if grep /^32$/, @flags;
+ return 8;
}
sub arr_size($) {
@@ -296,9 +328,13 @@ while (<$R>) {
next if $#{$this{args}} + 1 != scalar keys %{$this{argparams}};
- my $reg_formula = "($this{addr}";
+ my $reg_formula = "$this{addr}";
my $lim_formula;
+ chop $reg_formula;
+
+ $reg_formula = "(" . $reg_formula if $this{flagstring} ne "";
+
foreach my $arg (@{$this{args}}) {
my $d = $h->{$arg}->{discontig};
my $times = $h->{$arg}->{elsize} != 1 ?
@@ -315,11 +351,13 @@ while (<$R>) {
$lim_formula .= (defined $lim_formula ? " + " : "") . "($arg)$times";
}
- $reg_formula .= ")\n";
+ $reg_formula .= ")";
$lim_formula =~ s/^\(([a-z0-9]+)\)$/$1/i;
print $H tabconv sprintf("#define %-62s %s", "CCS_R_" . (uc $this{name}) .
- $this{arglist}, $reg_formula);
+ $this{arglist}, $reg_formula .
+ (($this{flagstring} eq "") ? "" :
+ " | " . $this{flagstring} . ")") . "\n");
print $H tabconv $hdr_data;
undef $hdr_data;
@@ -369,16 +407,23 @@ while (<$R>) {
$name =~ s/[,\.-]/_/g;
my $flagstring = "";
- my $size = elem_size(@flags);
- $flagstring .= "| CCS_FL_16BIT " if $size eq "2";
- $flagstring .= "| CCS_FL_32BIT " if $size eq "4";
+ my $bits = elem_bits(@flags);
+ if (! defined $kernel) {
+ $flagstring .= "| CCS_FL_16BIT " if $bits == 16;
+ $flagstring .= "| CCS_FL_32BIT " if $bits == 32;
+ }
$flagstring .= "| CCS_FL_FLOAT_IREAL " if grep /^float_ireal$/, @flags;
$flagstring .= "| CCS_FL_IREAL " if grep /^ireal$/, @flags;
$flagstring =~ s/^\| //;
$flagstring =~ s/ $//;
$flagstring = "($flagstring)" if $flagstring =~ /\|/;
my $base_addr = $addr;
- $addr = "($addr | $flagstring)" if $flagstring ne "";
+ $addr = "CCI_REG$bits($addr)" if defined $kernel;
+
+ if ($flagstring ne "" && !@$args) {
+ $addr = "($addr | $flagstring)";
+ $flagstring = "";
+ }
my $arglist = @$args ? "(" . (join ", ", @$args) . ")" : "";
$hdr_data .= sprintf "#define %-62s %s\n", "CCS_R_" . (uc $name), $addr
@@ -388,11 +433,12 @@ while (<$R>) {
%this = ( name => $name,
addr => $addr,
+ flagstring => $flagstring,
base_addr => $base_addr,
argparams => {},
args => $args,
arglist => $arglist,
- elsize => $size,
+ elsize => $bits / 8,
);
if (!@$args) {
diff --git a/Documentation/driver-api/media/tx-rx.rst b/Documentation/driver-api/media/tx-rx.rst
index e1e9258dd862..29d66a47b56e 100644
--- a/Documentation/driver-api/media/tx-rx.rst
+++ b/Documentation/driver-api/media/tx-rx.rst
@@ -6,8 +6,8 @@ Pixel data transmitter and receiver drivers
===========================================
V4L2 supports various devices that transmit and receive pixel data. Examples of
-these devices include a camera sensor, a TV tuner and a parallel or a CSI-2
-receiver in an SoC.
+these devices include a camera sensor, a TV tuner and a parallel, a BT.656 or a
+CSI-2 receiver in an SoC.
Bus types
---------
@@ -22,12 +22,13 @@ the host SoC. It is defined by the `MIPI alliance`_.
.. _`MIPI alliance`: https://www.mipi.org/
-Parallel
-^^^^^^^^
+Parallel and BT.656
+^^^^^^^^^^^^^^^^^^^
-`BT.601`_ and `BT.656`_ are the most common parallel busses.
+The parallel and `BT.656`_ buses transport one bit of data on each clock cycle
+per data line. The parallel bus uses synchronisation and other additional
+signals whereas BT.656 embeds synchronisation.
-.. _`BT.601`: https://en.wikipedia.org/wiki/Rec._601
.. _`BT.656`: https://en.wikipedia.org/wiki/ITU-R_BT.656
Transmitter drivers
@@ -90,8 +91,8 @@ where
pixel rate on the camera sensor's pixel array which is indicated by the
:ref:`V4L2_CID_PIXEL_RATE <v4l2-cid-pixel-rate>` control.
-LP-11 and LP-111 modes
-^^^^^^^^^^^^^^^^^^^^^^
+LP-11 and LP-111 states
+^^^^^^^^^^^^^^^^^^^^^^^
As part of transitioning to high speed mode, a CSI-2 transmitter typically
briefly sets the bus to LP-11 or LP-111 state, depending on the PHY. This period
@@ -105,7 +106,7 @@ in software, especially when there is no interrupt telling something is
happening.
One way to address this is to configure the transmitter side explicitly to LP-11
-or LP-111 mode, which requires support from the transmitter hardware. This is
+or LP-111 state, which requires support from the transmitter hardware. This is
not universally available. Many devices return to this state once streaming is
stopped while the state after power-on is LP-00 or LP-000.
@@ -116,11 +117,11 @@ transitioning to streaming state, but not yet start streaming. Similarly, the
to call ``.post_streamoff()`` for each successful call of ``.pre_streamon()``.
In the context of CSI-2, the ``.pre_streamon()`` callback is used to transition
-the transmitter to the LP-11 or LP-111 mode. This also requires powering on the
+the transmitter to the LP-11 or LP-111 state. This also requires powering on the
device, so this should be only done when it is needed.
-Receiver drivers that do not need explicit LP-11 or LP-111 mode setup are waived
-from calling the two callbacks.
+Receiver drivers that do not need explicit LP-11 or LP-111 state setup are
+waived from calling the two callbacks.
Stopping the transmitter
^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/Documentation/driver-api/media/v4l2-subdev.rst b/Documentation/driver-api/media/v4l2-subdev.rst
index e56b50b3f203..1db2ba27c54c 100644
--- a/Documentation/driver-api/media/v4l2-subdev.rst
+++ b/Documentation/driver-api/media/v4l2-subdev.rst
@@ -181,6 +181,8 @@ You can unregister a sub-device using:
Afterwards the subdev module can be unloaded and
:c:type:`sd <v4l2_subdev>`->dev == ``NULL``.
+.. _media-registering-async-subdevs:
+
Registering asynchronous sub-devices
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -195,6 +197,11 @@ performed using the :c:func:`v4l2_async_unregister_subdev` call. Subdevices
registered this way are stored in a global list of subdevices, ready to be
picked up by bridge drivers.
+Drivers must complete all initialization of the sub-device before
+registering it using :c:func:`v4l2_async_register_subdev`, including
+enabling runtime PM. This is because the sub-device becomes accessible
+as soon as it gets registered.
+
Asynchronous sub-device notifiers
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -562,8 +569,8 @@ device configuration. This is often implemented as e.g. an array of struct
v4l2_mbus_framefmt, one entry for each pad, and similarly for crop and compose
rectangles.
-In addition to the active configuration, each subdev file handle has an array of
-struct v4l2_subdev_pad_config, managed by the V4L2 core, which contains the try
+In addition to the active configuration, each subdev file handle has a struct
+v4l2_subdev_state, managed by the V4L2 core, which contains the try
configuration.
To simplify the subdev drivers the V4L2 subdev API now optionally supports a