libcamera: add the IMX896 sensor helper and properties (r3)

Teaches the software ISP's AGC the IMX896 gain law
(gain = 16384/(16384-code), inverted from the vendor driver and
round-tripped against all 3009 vendor gain-table entries, max error
0.049%) and adds the sensor properties (1.0um unit cell, test-pattern
map). Same shape as the OV13B10 pair; both verified to apply and
compile on v0.7.2 after 0001-0004.

The extracted-CCM tuning yaml is deliberately NOT packaged yet - the
color matrices come from the vendor Chromatix blob and the licensing
call is open (see the camera journal).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

aports/temp/libcamera/0005-libipa-Add-camera-sensor-helper-for-IMX896.patch

@@ -0,0 +1,47 @@
+From 4008fe2ced7bbf1026267ec47028b735173cc0db Mon Sep 17 00:00:00 2001
+From: Jorijn van der Graaf <jorijnvdgraaf@catcrafts.net>
+Date: Sun, 16 Aug 2026 20:49:31 +0200
+Subject: [PATCH] libipa: Add camera sensor helper for IMX896
+
+The Sony IMX896 (main sensor on the Fairphone 6 / milos) needs a
+CameraSensorHelper so the software ISP AGC can map the analogue gain
+register code to a real gain multiplier. Without it libcamera logs
+"IPASoft: Failed to create camera sensor helper for imx896" and the
+AGC misinterprets the raw gain code (0..16128) as a linear gain.
+
+The IMX896 uses the common Sony analogue gain model with a 14 bit
+code: gain = 16384 / (16384 - code), so code 0 is 1x and the maximum
+code 16128 is 64x. Derived from the vendor kernel driver's gain2reg
+conversion (regGain = 16384 - 16384 * BASEGAIN / gain, with the gain
+table spanning 1024..65536 in 1/1024 units) and matching the mainline
+imx896 driver's gain register documentation.
+
+Assisted-by: Claude:claude-fable-5
+---
+ src/ipa/libipa/camera_sensor_helper.cpp | 10 ++++++++++
+ 1 file changed, 10 insertions(+)
+
+diff --git a/src/ipa/libipa/camera_sensor_helper.cpp b/src/ipa/libipa/camera_sensor_helper.cpp
+index 9457d62..cf2482b 100644
+--- a/src/ipa/libipa/camera_sensor_helper.cpp
++++ b/src/ipa/libipa/camera_sensor_helper.cpp
+@@ -665,6 +665,16 @@ public:
+ };
+ REGISTER_CAMERA_SENSOR_HELPER("imx708", CameraSensorHelperImx708)
+ 
++class CameraSensorHelperImx896 : public CameraSensorHelper
++{
++public:
++	CameraSensorHelperImx896()
++	{
++		gain_ = AnalogueGainLinear{ 0, 16384, -1, 16384 };
++	}
++};
++REGISTER_CAMERA_SENSOR_HELPER("imx896", CameraSensorHelperImx896)
++
+ class CameraSensorHelperOv01a10 : public CameraSensorHelper
+ {
+ public:
+-- 
+2.55.0
+

aports/temp/libcamera/0006-libcamera-sensor-Add-IMX896-sensor-properties.patch

@@ -0,0 +1,41 @@
+From 262906b13ff727473679cf7895618e4745f3ba4c Mon Sep 17 00:00:00 2001
+From: Jorijn van der Graaf <jorijnvdgraaf@catcrafts.net>
+Date: Sun, 16 Aug 2026 20:49:31 +0200
+Subject: [PATCH] libcamera: sensor: Add IMX896 sensor properties
+
+Add the Sony IMX896 (Fairphone 6 main camera, 50 MP, 8192x6144) to
+the static properties database: 1.0 um unit cell and the test pattern
+modes exposed by the kernel driver (V4L2 menu indices map 1:1 to
+register 0x0600 values). Removes the "No static properties available
+for 'imx896'" warning.
+
+Assisted-by: Claude:claude-fable-5
+---
+ src/libcamera/sensor/camera_sensor_properties.cpp | 11 +++++++++++
+ 1 file changed, 11 insertions(+)
+
+diff --git a/src/libcamera/sensor/camera_sensor_properties.cpp b/src/libcamera/sensor/camera_sensor_properties.cpp
+index 2804315..63050c2 100644
+--- a/src/libcamera/sensor/camera_sensor_properties.cpp
++++ b/src/libcamera/sensor/camera_sensor_properties.cpp
+@@ -335,6 +335,17 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
+ 				.hblankDelay = 3
+ 			},
+ 		} },
++		{ "imx896", {
++			.unitCellSize = { 1000, 1000 },
++			.testPatternModes = {
++				{ controls::draft::TestPatternModeOff, 0 },
++				{ controls::draft::TestPatternModeSolidColor, 1 },
++				{ controls::draft::TestPatternModeColorBars, 2 },
++				{ controls::draft::TestPatternModeColorBarsFadeToGray, 3 },
++				{ controls::draft::TestPatternModePn9, 4 },
++			},
++			.sensorDelays = { },
++		} },
+ 		{ "ov2685", {
+ 			.unitCellSize = { 1750, 1750 },
+ 			.testPatternModes = {
+-- 
+2.55.0
+

aports/temp/libcamera/APKBUILD

@@ -3,7 +3,7 @@ maintainer="Robert Mader <robert.mader@collabora.com>"
 pkgname=libcamera
 _pkgver=0.7.2
 pkgver=9999$_pkgver
-pkgrel=2
+pkgrel=3
 pkgdesc="Linux camera framework"
 url="https://libcamera.org/"
 arch="all"
@@ -61,6 +61,8 @@ source="https://gitlab.freedesktop.org/camera/libcamera/-/archive/v$_pkgver/libc
 	0002-libcamera-simple-Skip-hwISP-formats-if-swISP-is-acti.patch
 	0003-libipa-Add-OV13B10-camera-sensor-helper.patch
 	0004-libcamera-sensor-Add-OV13B10-sensor-properties.patch
+	0005-libipa-Add-camera-sensor-helper-for-IMX896.patch
+	0006-libcamera-sensor-Add-IMX896-sensor-properties.patch
 	qcam.desktop
 	$_tuning_files
 	"
@@ -178,6 +180,8 @@ eef5e38efc874f2049d17f08b04d9f21c3e4616f66873358cd2c446e651f78d6952ae25ee13a6ef9
 191dfa09cfd08bcdf0d0d07410d17af590cf78b8bc8f8b7587fd2dc1c645a9ca07f2926b5d98381c011319b1f4e1d6195dd0d6dba65fd8c723882e6be0d6117d  0002-libcamera-simple-Skip-hwISP-formats-if-swISP-is-acti.patch
 594e2c31bd51dac8f5f184b026301028431b1c67e48edb245790444713b64e927fac99cb8a33f0b7042c9689359079158b3f1d344b250904472c977f1313f83e  0003-libipa-Add-OV13B10-camera-sensor-helper.patch
 89e0fc4a12aa4d5fbdc77b50e28b0a6d2cf8dfeb884b536507b6c24aa2ae5c616a32a517deb086e3284c72a82e6d6ddcf6eaa88f6c1c021adc6a0167194b7711  0004-libcamera-sensor-Add-OV13B10-sensor-properties.patch
+f746cff46f78a8e7bd4cadd72c4ab05044971e36e412a56d4a14a420aeb1c9168b1f4ef411f4cc81a596159cab3d8a3713214a4ff0b2a4daf839b1a380c09b6e  0005-libipa-Add-camera-sensor-helper-for-IMX896.patch
+1ac9747c941787c7ae76ed6520585b0d26494eb0f697bd74a9155ed04736a7b61f838dfb1bad01cf13b9cdd36f644a95a6ec1cbfe4f5c5a42cb23d4b6d9aa166  0006-libcamera-sensor-Add-IMX896-sensor-properties.patch
 22167a4eceb6d1b40b0b7c45fdf116c71684f5340de7f767535cb8e160ad9d2ae0f00cb3d461f73a344520a48a4641cf46226841d78bee06bfbfd2a91337f754  qcam.desktop
 2ee566653b17d565d2c0de67cbe6ebad25df5aac6051cad78e6bae52016fa2ca0247e964d735ac776b3e0bd447ead9c4fcb26cd7629228cdba3ceb91b46f378f  hi846.yaml
 55dab9dcb9b1982143b9d63e4e51138c5bffd7c8f4a8e4e122750b3ad9d475446956bc297d9f564819ade4be75a575d06633a064e14f8ba3ef77986783c5f067  imx355.yaml