media: i2c: Add support for alvium camera

The Alvium camera is shipped with sensor + isp in the same housing.
The camera can be equipped with one out of various sensor and abstract
the user from this. Camera is connected via MIPI CSI-2.

Most of the camera module features are supported, with the main exception
being fw update.

The driver provides all mandatory, optional and recommended V4L2 controls
for maximum compatibility with libcamera

References:
 - https://www.alliedvision.com/en/products/embedded-vision-solutionsSigned-off-by: Tommaso Merciai <tomm.merciai@gmail.com>
[Sakari Ailus: Assign ret before using it in probe and squash Tommaso's
	       other fixes.]
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil: alvium-csi2.h: SPDX must use /* */ instead of //]

MAINTAINERS

@@ -711,6 +711,15 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/media/allegro,al5e.yaml
 F:	drivers/media/platform/allegro-dvt/
 
+ALLIED VISION ALVIUM CAMERA DRIVER
+M:	Tommaso Merciai <tomm.merciai@gmail.com>
+M:	Martin Hecht <martin.hecht@avnet.eu>
+L:	linux-media@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/media/i2c/alliedvision,alvium-csi2.yaml
+F:	drivers/media/i2c/alvium-csi2.c
+F:	drivers/media/i2c/alvium-csi2.h
+
 ALLWINNER A10 CSI DRIVER
 M:	Maxime Ripard <mripard@kernel.org>
 L:	linux-media@vger.kernel.org

drivers/media/i2c/Kconfig

@@ -41,6 +41,16 @@ config VIDEO_APTINA_PLL
 config VIDEO_CCS_PLL
 	tristate
 
+config VIDEO_ALVIUM_CSI2
+	tristate "Allied Vision ALVIUM MIPI CSI-2 camera support"
+	select V4L2_CCI_I2C
+	help
+	  This is a Video4Linux2 sensor-level driver for the Allied Vision
+	  ALVIUM camera connected via MIPI CSI-2 interface.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called alvium-csi2.
+
 config VIDEO_AR0521
 	tristate "ON Semiconductor AR0521 sensor support"
 	help

drivers/media/i2c/Makefile

@@ -17,6 +17,7 @@ obj-$(CONFIG_VIDEO_ADV7604) += adv7604.o
 obj-$(CONFIG_VIDEO_ADV7842) += adv7842.o
 obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
 obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
+obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
 obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
 obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
 obj-$(CONFIG_VIDEO_BT819) += bt819.o