media: cadence: csi2rx: Add get_fmt and set_fmt pad ops

The format is needed to calculate the link speed for the external DPHY
configuration. It is not right to query the format from the source
subdev. Add get_fmt and set_fmt pad operations so that the format can be
configured and correct bpp be selected.

Initialize and use the v4l2 subdev active state to keep track of the
active formats. Also propagate the new format from the sink pad to all
the source pads.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Tested-by: Julien Massot <julien.massot@collabora.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Co-developed-by: Jai Luthra <j-luthra@ti.com>
Signed-off-by: Jai Luthra <j-luthra@ti.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

Author: Pratyush Yadav

drivers/media/platform/cadence/cdns-csi2rx.c

@@ -61,6 +61,11 @@ enum csi2rx_pads {
 	CSI2RX_PAD_MAX,
 };
 
+struct csi2rx_fmt {
+	u32				code;
+	u8				bpp;
+};
+
 struct csi2rx_priv {
 	struct device			*dev;
 	unsigned int			count;
@@ -95,6 +100,32 @@ struct csi2rx_priv {
 	int				source_pad;
 };
 
+static const struct csi2rx_fmt formats[] = {
+	{ .code	= MEDIA_BUS_FMT_YUYV8_1X16, .bpp = 16, },
+	{ .code	= MEDIA_BUS_FMT_UYVY8_1X16, .bpp = 16, },
+	{ .code	= MEDIA_BUS_FMT_YVYU8_1X16, .bpp = 16, },
+	{ .code	= MEDIA_BUS_FMT_VYUY8_1X16, .bpp = 16, },
+	{ .code	= MEDIA_BUS_FMT_SBGGR8_1X8, .bpp = 8, },
+	{ .code	= MEDIA_BUS_FMT_SGBRG8_1X8, .bpp = 8, },
+	{ .code	= MEDIA_BUS_FMT_SGRBG8_1X8, .bpp = 8, },
+	{ .code	= MEDIA_BUS_FMT_SRGGB8_1X8, .bpp = 8, },
+	{ .code	= MEDIA_BUS_FMT_SBGGR10_1X10, .bpp = 10, },
+	{ .code	= MEDIA_BUS_FMT_SGBRG10_1X10, .bpp = 10, },
+	{ .code	= MEDIA_BUS_FMT_SGRBG10_1X10, .bpp = 10, },
+	{ .code	= MEDIA_BUS_FMT_SRGGB10_1X10, .bpp = 10, },
+};
+
+static const struct csi2rx_fmt *csi2rx_get_fmt_by_code(u32 code)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(formats); i++)
+		if (formats[i].code == code)
+			return &formats[i];
+
+	return NULL;
+}
+
 static inline
 struct csi2rx_priv *v4l2_subdev_to_csi2rx(struct v4l2_subdev *subdev)
 {
@@ -303,12 +334,68 @@ static int csi2rx_s_stream(struct v4l2_subdev *subdev, int enable)
 	return ret;
 }
 
+static int csi2rx_set_fmt(struct v4l2_subdev *subdev,
+			  struct v4l2_subdev_state *state,
+			  struct v4l2_subdev_format *format)
+{
+	struct v4l2_mbus_framefmt *fmt;
+	unsigned int i;
+
+	/* No transcoding, source and sink formats must match. */
+	if (format->pad != CSI2RX_PAD_SINK)
+		return v4l2_subdev_get_fmt(subdev, state, format);
+
+	if (!csi2rx_get_fmt_by_code(format->format.code))
+		format->format.code = formats[0].code;
+
+	format->format.field = V4L2_FIELD_NONE;
+
+	/* Set sink format */
+	fmt = v4l2_subdev_get_pad_format(subdev, state, format->pad);
+	*fmt = format->format;
+
+	/* Propagate to source formats */
+	for (i = CSI2RX_PAD_SOURCE_STREAM0; i < CSI2RX_PAD_MAX; i++) {
+		fmt = v4l2_subdev_get_pad_format(subdev, state, i);
+		*fmt = format->format;
+	}
+
+	return 0;
+}
+
+static int csi2rx_init_cfg(struct v4l2_subdev *subdev,
+			   struct v4l2_subdev_state *state)
+{
+	struct v4l2_subdev_format format = {
+		.pad = CSI2RX_PAD_SINK,
+		.format = {
+			.width = 640,
+			.height = 480,
+			.code = MEDIA_BUS_FMT_UYVY8_1X16,
+			.field = V4L2_FIELD_NONE,
+			.colorspace = V4L2_COLORSPACE_SRGB,
+			.ycbcr_enc = V4L2_YCBCR_ENC_601,
+			.quantization = V4L2_QUANTIZATION_LIM_RANGE,
+			.xfer_func = V4L2_XFER_FUNC_SRGB,
+		},
+	};
+
+	return csi2rx_set_fmt(subdev, state, &format);
+}
+
+static const struct v4l2_subdev_pad_ops csi2rx_pad_ops = {
+	.get_fmt	= v4l2_subdev_get_fmt,
+	.set_fmt	= csi2rx_set_fmt,
+	.init_cfg	= csi2rx_init_cfg,
+};
+
 static const struct v4l2_subdev_video_ops csi2rx_video_ops = {
 	.s_stream	= csi2rx_s_stream,
 };
 
 static const struct v4l2_subdev_ops csi2rx_subdev_ops = {
 	.video		= &csi2rx_video_ops,
+	.pad		= &csi2rx_pad_ops,
 };
 
 static int csi2rx_async_bound(struct v4l2_async_notifier *notifier,
@@ -532,9 +619,13 @@ static int csi2rx_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_cleanup;
 
+	ret = v4l2_subdev_init_finalize(&csi2rx->subdev);
+	if (ret)
+		goto err_cleanup;
+
 	ret = v4l2_async_register_subdev(&csi2rx->subdev);
 	if (ret < 0)
-		goto err_cleanup;
+		goto err_free_state;
 
 	dev_info(&pdev->dev,
 		 "Probed CSI2RX with %u/%u lanes, %u streams, %s D-PHY\n",
@@ -544,6 +635,8 @@ static int csi2rx_probe(struct platform_device *pdev)
 
 	return 0;
 
+err_free_state:
+	v4l2_subdev_cleanup(&csi2rx->subdev);
 err_cleanup:
 	v4l2_async_nf_unregister(&csi2rx->notifier);
 	v4l2_async_nf_cleanup(&csi2rx->notifier);
@@ -560,6 +653,7 @@ static void csi2rx_remove(struct platform_device *pdev)
 	v4l2_async_nf_unregister(&csi2rx->notifier);
 	v4l2_async_nf_cleanup(&csi2rx->notifier);
 	v4l2_async_unregister_subdev(&csi2rx->subdev);
+	v4l2_subdev_cleanup(&csi2rx->subdev);
 	media_entity_cleanup(&csi2rx->subdev.entity);
 	kfree(csi2rx);
 }