media: microchip: microchip-isc: implement media controller

As a top MC video driver, the microchip-isc should not propagate the format
to the subdevice, it should rather check at start_streaming() time if the
subdev is properly configured with a compatible format.
Removed the whole format finding logic, and reworked the format
verification at start_streaming time, such that the ISC will return an
error if the subdevice is not properly configured.
To achieve this, media_pipeline_start is called and a link_validate
callback is created to check the formats.
With this being done, the module parameter 'sensor_preferred' makes no
sense anymore. The ISC should not decide which format the sensor is using.
The ISC should only cope with the situation and inform userspace if the
streaming is possible in the current configuration.
The redesign of the format propagation has also risen the question of the
enumfmt callback. If enumfmt is called with an mbus_code, the enumfmt
handler should only return the formats that are supported for this
mbus_code. Otherwise, the enumfmt will report all the formats that the ISC
could output.
With this rework, the dynamic list of user formats is removed. It makes no
more sense to identify at complete time which formats the sensor could
emit, and add those into a separate dynamic list.
The ISC will start with a simple preconfigured default format, and at
link validate time, decide whether it can use the format that is
configured on the sink or not.
>From now on, the driver also advertises the IO_MC capability.
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/microchip/Kconfig

@@ -23,7 +23,7 @@ config VIDEO_MICROCHIP_ISC
 config VIDEO_MICROCHIP_XISC
 	tristate "Microchip eXtended Image Sensor Controller (XISC) support"
 	depends on V4L_PLATFORM_DRIVERS
-	depends on VIDEO_DEV && COMMON_CLK && VIDEO_V4L2_SUBDEV_API
+	depends on VIDEO_DEV && COMMON_CLK
 	depends on ARCH_AT91 || COMPILE_TEST
 	select VIDEOBUF2_DMA_CONTIG
 	select REGMAP_MMIO

drivers/media/platform/microchip/microchip-isc-scaler.c

@@ -173,6 +173,10 @@ static const struct v4l2_subdev_pad_ops isc_scaler_pad_ops = {
 	.init_cfg = isc_scaler_init_cfg,
 };
 
+static const struct media_entity_operations isc_scaler_entity_ops = {
+	.link_validate = v4l2_subdev_link_validate,
+};
+
 static const struct v4l2_subdev_ops xisc_scaler_subdev_ops = {
 	.pad = &isc_scaler_pad_ops,
 };
@@ -190,6 +194,7 @@ int isc_scaler_init(struct isc_device *isc)
 
 	isc->scaler_sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
 	isc->scaler_sd.entity.function = MEDIA_ENT_F_PROC_VIDEO_SCALER;
+	isc->scaler_sd.entity.ops = &isc_scaler_entity_ops;
 	isc->scaler_pads[ISC_SCALER_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
 	isc->scaler_pads[ISC_SCALER_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
 

drivers/media/platform/microchip/microchip-isc.h

@@ -63,15 +63,16 @@ struct isc_subdev_entity {
  * @cfa_baycfg:		If this format is RAW BAYER, indicate the type of bayer.
 			this is either BGBG, RGRG, etc.
  * @pfe_cfg0_bps:	Number of hardware data lines connected to the ISC
+ * @raw:		If the format is raw bayer.
  */
 
 struct isc_format {
 	u32	fourcc;
 	u32	mbus_code;
 	u32	cfa_baycfg;
-
-	bool	sd_support;
 	u32	pfe_cfg0_bps;
+
+	bool	raw;
 };
 
 /* Pipeline bitmap */
@@ -216,8 +217,7 @@ enum isc_scaler_pads {
  * @comp:		completion reference that signals frame completion
  *
  * @fmt:		current v42l format
- * @user_formats:	list of formats that are supported and agreed with sd
- * @num_user_formats:	how many formats are in user_formats
+ * @try_fmt:		current v4l2 try format
  *
  * @config:		current ISC format configuration
  * @try_config:		the current ISC try format , not yet activated
@@ -272,6 +272,7 @@ enum isc_scaler_pads {
  * @formats_list_size:	size of formats_list array
  * @pads:		media controller pads for isc video entity
  * @mdev:		media device that is registered by the isc
+ * @mpipe:		media device pipeline used by the isc
  * @remote_pad:		remote pad on the connected subdevice
  * @scaler_sd:		subdevice for the scaler that isc registers
  * @scaler_pads:	media controller pads for the scaler subdevice
@@ -298,8 +299,7 @@ struct isc_device {
 	struct completion	comp;
 
 	struct v4l2_format	fmt;
-	struct isc_format	**user_formats;
-	unsigned int		num_user_formats;
+	struct v4l2_format	try_fmt;
 
 	struct fmt_config	config;
 	struct fmt_config	try_config;
@@ -369,6 +369,7 @@ struct isc_device {
 	struct {
 		struct media_pad		pads[ISC_PADS_NUM];
 		struct media_device		mdev;
+		struct media_pipeline		mpipe;
 
 		u32				remote_pad;
 	};

drivers/media/platform/microchip/microchip-sama5d2-isc.c

@@ -80,20 +80,40 @@ static const struct isc_format sama5d2_controller_formats[] = {
 		.fourcc		= V4L2_PIX_FMT_Y10,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SBGGR8,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGBRG8,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGRBG8,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SRGGB8,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SBGGR10,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGBRG10,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGRBG10,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SRGGB10,
+		.raw		= true,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SBGGR12,
+		.raw		= true,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGBRG12,
+		.raw		= true,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGRBG12,
+		.raw		= true,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SRGGB12,
+		.raw		= true,
 	},
 };
 

drivers/media/platform/microchip/microchip-sama7g5-isc.c

@@ -89,20 +89,40 @@ static const struct isc_format sama7g5_controller_formats[] = {
 		.fourcc		= V4L2_PIX_FMT_Y16,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SBGGR8,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGBRG8,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGRBG8,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SRGGB8,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SBGGR10,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGBRG10,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGRBG10,
+		.raw		= true,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SRGGB10,
+		.raw		= true,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SBGGR12,
+		.raw		= true,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGBRG12,
+		.raw		= true,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGRBG12,
+		.raw		= true,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SRGGB12,
+		.raw		= true,
 	},
 };