[PATCH v7 03/13] media: cadence: csi2rx: Add get_fmt and set_fmt pad ops

[Vaishnav Achath]

From: Pratyush Yadav <p.yadav@xxxxxx>

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.

Signed-off-by: Pratyush Yadav <p.yadav@xxxxxx>
Signed-off-by: Vaishnav Achath <vaishnav.a@xxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---

Changes in v7:
- Add Laurent's R-by.

Changes in v6:
- Move the lock around the dereference for framefmt in
  csi2rx_{get,set}_fmt() instead of when we get the pointer.
- Do not return an error when an unsupported format is set. Instead
  adjust the code to the first format in the list.
- Not adding Laurent's R-by since I am making changes in
  csi2rx_set_fmt() that he didn't explicitly recommend.

Changes in v5:
- Use YUV 1X16 formats instead of 2X8.
- New in v5.

 drivers/media/platform/cadence/cdns-csi2rx.c | 131 +++++++++++++++++++
 1 file changed, 131 insertions(+)

diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
index 2547903f2e8e..ae3ebdb3890d 100644
--- a/drivers/media/platform/cadence/cdns-csi2rx.c
+++ b/drivers/media/platform/cadence/cdns-csi2rx.c
@@ -54,6 +54,11 @@ enum csi2rx_pads {
 	CSI2RX_PAD_MAX,
 };
 
+struct csi2rx_fmt {
+	u32				code;
+	u8				bpp;
+};
+
 struct csi2rx_priv {
 	struct device			*dev;
 	unsigned int			count;
@@ -79,12 +84,43 @@ struct csi2rx_priv {
 	struct v4l2_subdev		subdev;
 	struct v4l2_async_notifier	notifier;
 	struct media_pad		pads[CSI2RX_PAD_MAX];
+	struct v4l2_mbus_framefmt	fmt;
 
 	/* Remote source */
 	struct v4l2_subdev		*source_subdev;
 	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,
+	},
+};
+
+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)
 {
@@ -236,12 +272,103 @@ static int csi2rx_s_stream(struct v4l2_subdev *subdev, int enable)
 	return ret;
 }
 
+static struct v4l2_mbus_framefmt *
+csi2rx_get_pad_format(struct csi2rx_priv *csi2rx,
+		      struct v4l2_subdev_state *state,
+		      unsigned int pad, u32 which)
+{
+	switch (which) {
+	case V4L2_SUBDEV_FORMAT_TRY:
+		return v4l2_subdev_get_try_format(&csi2rx->subdev, state, pad);
+	case V4L2_SUBDEV_FORMAT_ACTIVE:
+		return &csi2rx->fmt;
+	default:
+		return NULL;
+	}
+}
+
+static int csi2rx_get_fmt(struct v4l2_subdev *subdev,
+			  struct v4l2_subdev_state *state,
+			  struct v4l2_subdev_format *format)
+{
+	struct csi2rx_priv *csi2rx = v4l2_subdev_to_csi2rx(subdev);
+	struct v4l2_mbus_framefmt *framefmt;
+
+	framefmt = csi2rx_get_pad_format(csi2rx, state, format->pad,
+					 format->which);
+	if (!framefmt)
+		return -EINVAL;
+
+	mutex_lock(&csi2rx->lock);
+	format->format = *framefmt;
+	mutex_unlock(&csi2rx->lock);
+
+	return 0;
+}
+
+static int csi2rx_set_fmt(struct v4l2_subdev *subdev,
+			  struct v4l2_subdev_state *state,
+			  struct v4l2_subdev_format *format)
+{
+	struct csi2rx_priv *csi2rx = v4l2_subdev_to_csi2rx(subdev);
+	struct v4l2_mbus_framefmt *framefmt;
+
+	/* No transcoding, source and sink formats must match. */
+	if (format->pad != CSI2RX_PAD_SINK)
+		return csi2rx_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;
+
+	framefmt = csi2rx_get_pad_format(csi2rx, state, format->pad,
+					 format->which);
+	if (!framefmt)
+		return -EINVAL;
+
+	mutex_lock(&csi2rx->lock);
+	*framefmt = format->format;
+	mutex_unlock(&csi2rx->lock);
+
+	return 0;
+}
+
+static int csi2rx_init_cfg(struct v4l2_subdev *subdev,
+			   struct v4l2_subdev_state *state)
+{
+	struct v4l2_subdev_format format = {
+		.which = state ? V4L2_SUBDEV_FORMAT_TRY
+			: V4L2_SUBDEV_FORMAT_ACTIVE,
+		.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	= csi2rx_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,
@@ -457,6 +584,10 @@ static int csi2rx_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_cleanup;
 
+	ret = csi2rx_init_cfg(&csi2rx->subdev, NULL);
+	if (ret)
+		goto err_cleanup;
+
 	ret = v4l2_async_register_subdev(&csi2rx->subdev);
 	if (ret < 0)
 		goto err_cleanup;
-- 
2.17.1