[PATCH v4 27/36] media: imx: csi: add support for bayer formats

Steve Longerbeam
2017-02-16T02:19:29Z

From: Russell King <rmk+kernel@armlinux.org.uk>

Bayer formats must be treated as generic data and passthrough mode must
be used. Add the correct setup for these formats.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

- added check to csi_link_validate() to verify that destination is
IDMAC output pad when passthrough conditions exist: bayer formats
and 16-bit parallel buses.

Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
---
drivers/staging/media/imx/imx-media-csi.c | 50 ++++++++++++++++++++++++++-----
1 file changed, 42 insertions(+), 8 deletions(-)

diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
index 0343fc3..ae24b42 100644
--- a/drivers/staging/media/imx/imx-media-csi.c
+++ b/drivers/staging/media/imx/imx-media-csi.c
@@ -2,6 +2,7 @@
* V4L2 Capture CSI Subdev for Freescale i.MX5/6 SOC
*
* Copyright (c) 2014-2016 Mentor Graphics Inc.
+ * Copyright (C) 2017 Pengutronix, Philipp Zabel <kernel@pengutronix.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -271,10 +272,11 @@ static int csi_idmac_setup_channel(struct csi_priv *priv)
struct imx_media_video_dev *vdev = priv->vdev;
struct v4l2_of_endpoint *sensor_ep;
struct v4l2_mbus_framefmt *infmt;
- unsigned int burst_size;
struct ipu_image image;
+ u32 passthrough_bits;
dma_addr_t phys[2];
bool passthrough;
+ u32 burst_size;
int ret;

infmt = &priv->format_mbus[CSI_SINK_PAD];
@@ -301,15 +303,38 @@ static int csi_idmac_setup_channel(struct csi_priv *priv)
ipu_cpmem_set_burstsize(priv->idmac_ch, burst_size);

/*
- * If the sensor uses 16-bit parallel CSI bus, we must handle
- * the data internally in the IPU as 16-bit generic, aka
- * passthrough mode.
+ * Check for conditions that require the IPU to handle the
+ * data internally as generic data, aka passthrough mode:
+ * - raw bayer formats
+ * - the sensor bus is 16-bit parallel
*/
- passthrough = (sensor_ep->bus_type != V4L2_MBUS_CSI2 &&
- sensor_ep->bus.parallel.bus_width >= 16);
+ switch (image.pix.pixelformat) {
+ case V4L2_PIX_FMT_SBGGR8:
+ case V4L2_PIX_FMT_SGBRG8:
+ case V4L2_PIX_FMT_SGRBG8:
+ case V4L2_PIX_FMT_SRGGB8:
+ burst_size = 8;
+ passthrough = true;
+ passthrough_bits = 8;
+ break;
+ case V4L2_PIX_FMT_SBGGR16:
+ case V4L2_PIX_FMT_SGBRG16:
+ case V4L2_PIX_FMT_SGRBG16:
+ case V4L2_PIX_FMT_SRGGB16:
+ burst_size = 4;
+ passthrough = true;
+ passthrough_bits = 16;
+ break;
+ default:
+ passthrough = (sensor_ep->bus_type != V4L2_MBUS_CSI2 &&
+ sensor_ep->bus.parallel.bus_width >= 16);
+ passthrough_bits = 16;
+ break;
+ }

if (passthrough)
- ipu_cpmem_set_format_passthrough(priv->idmac_ch, 16);
+ ipu_cpmem_set_format_passthrough(priv->idmac_ch,
+ passthrough_bits);

/*
* Set the channel for the direct CSI-->memory via SMFC
@@ -695,6 +720,7 @@ static int csi_link_validate(struct v4l2_subdev *sd,
struct v4l2_subdev_format *sink_fmt)
{
struct csi_priv *priv = v4l2_get_subdevdata(sd);
+ const struct imx_media_pixfmt *incc;
struct v4l2_of_endpoint *sensor_ep;
bool is_csi2;
int ret;
@@ -713,8 +739,16 @@ static int csi_link_validate(struct v4l2_subdev *sd,
}

sensor_ep = &priv->sensor->sensor_ep;
-
is_csi2 = (sensor_ep->bus_type == V4L2_MBUS_CSI2);
+ incc = priv->cc[CSI_SINK_PAD];
+
+ if (priv->dest != IPU_CSI_DEST_IDMAC &&
+ (incc->bayer || (!is_csi2 &&
+ sensor_ep->bus.parallel.bus_width >= 16))) {
+ v4l2_err(&priv->sd,
+ "bayer/16-bit parallel buses must go to IDMAC pad\n");
+ return -EINVAL;
+ }

if (is_csi2) {
int vc_num = 0;
--
2.7.4