[PATCH 12/20] media: imx: Add CSI subdev driver

[Steve Longerbeam <slongerbeam@gmail.com>]

This is a media entity subdevice for the i.MX Camera
Serial Interface module.

Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
---
 drivers/staging/media/imx/Kconfig   |  13 +
 drivers/staging/media/imx/Makefile  |   2 +
 drivers/staging/media/imx/imx-csi.c | 638 ++++++++++++++++++++++++++++++++++++
 3 files changed, 653 insertions(+)
 create mode 100644 drivers/staging/media/imx/imx-csi.c

diff --git a/drivers/staging/media/imx/Kconfig b/drivers/staging/media/imx/Kconfig
index bfde58d..ce2d2c8 100644
--- a/drivers/staging/media/imx/Kconfig
+++ b/drivers/staging/media/imx/Kconfig
@@ -6,3 +6,16 @@ config VIDEO_IMX_MEDIA
 	  Say yes here to enable support for video4linux media controller
 	  driver for the i.MX5/6 SOC.
 
+if VIDEO_IMX_MEDIA
+menu "i.MX5/6 Media Sub devices"
+
+config VIDEO_IMX_CAMERA
+	tristate "i.MX5/6 Camera driver"
+	depends on VIDEO_IMX_MEDIA && VIDEO_DEV && I2C
+	select VIDEOBUF2_DMA_CONTIG
+	default y
+	---help---
+	  A video4linux camera capture driver for i.MX5/6.
+
+endmenu
+endif
diff --git a/drivers/staging/media/imx/Makefile b/drivers/staging/media/imx/Makefile
index ef9f11b..133672a 100644
--- a/drivers/staging/media/imx/Makefile
+++ b/drivers/staging/media/imx/Makefile
@@ -4,3 +4,5 @@ imx-media-objs := imx-media-dev.o imx-media-fim.o imx-media-internal-sd.o \
 obj-$(CONFIG_VIDEO_IMX_MEDIA) += imx-media.o
 obj-$(CONFIG_VIDEO_IMX_MEDIA) += imx-media-common.o
 
+obj-$(CONFIG_VIDEO_IMX_CAMERA) += imx-csi.o
+
diff --git a/drivers/staging/media/imx/imx-csi.c b/drivers/staging/media/imx/imx-csi.c
new file mode 100644
index 0000000..975eafb
--- /dev/null
+++ b/drivers/staging/media/imx/imx-csi.c
@@ -0,0 +1,638 @@
+/*
+ * V4L2 Capture CSI Subdev for Freescale i.MX5/6 SOC
+ *
+ * Copyright (c) 2014-2016 Mentor Graphics Inc.
+ *
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-subdev.h>
+#include <media/videobuf2-dma-contig.h>
+#include <media/v4l2-of.h>
+#include <media/v4l2-ctrls.h>
+#include <video/imx-ipu-v3.h>
+#include "imx-media.h"
+
+#define CSI_NUM_PADS 2
+
+struct csi_priv {
+	struct device *dev;
+	struct ipu_soc *ipu;
+	struct imx_media_dev *md;
+	struct v4l2_subdev sd;
+	struct media_pad pad[CSI_NUM_PADS];
+	struct v4l2_mbus_framefmt format_mbus[CSI_NUM_PADS];
+	struct v4l2_mbus_config sensor_mbus_cfg;
+	struct v4l2_rect crop;
+	struct ipu_csi *csi;
+	int csi_id;
+	int input_pad;
+	int output_pad;
+	bool power_on;  /* power is on */
+	bool stream_on; /* streaming is on */
+
+	/* the sink for the captured frames */
+	struct v4l2_subdev *sink_sd;
+	enum ipu_csi_dest dest;
+	struct v4l2_subdev *src_sd;
+
+	struct v4l2_ctrl_handler ctrl_hdlr;
+	struct imx_media_fim *fim;
+
+	/* the attached sensor at stream on */
+	struct imx_media_subdev *sensor;
+};
+
+static inline struct csi_priv *sd_to_dev(struct v4l2_subdev *sdev)
+{
+	return container_of(sdev, struct csi_priv, sd);
+}
+
+/* Update the CSI whole sensor and active windows */
+static int csi_setup(struct csi_priv *priv)
+{
+	struct v4l2_mbus_framefmt infmt;
+
+	ipu_csi_set_window(priv->csi, &priv->crop);
+
+	/*
+	 * the ipu-csi doesn't understand ALTERNATE, but it only
+	 * needs to know whether the stream is interlaced, so set
+	 * to INTERLACED if infmt field is ALTERNATE.
+	 */
+	infmt = priv->format_mbus[priv->input_pad];
+	if (infmt.field == V4L2_FIELD_ALTERNATE)
+		infmt.field = V4L2_FIELD_INTERLACED;
+
+	ipu_csi_init_interface(priv->csi, &priv->sensor_mbus_cfg, &infmt);
+
+	ipu_csi_set_dest(priv->csi, priv->dest);
+
+	ipu_csi_dump(priv->csi);
+
+	return 0;
+}
+
+static int csi_start(struct csi_priv *priv)
+{
+	int ret;
+
+	if (!priv->sensor) {
+		v4l2_err(&priv->sd, "no sensor attached\n");
+		return -EINVAL;
+	}
+
+	ret = csi_setup(priv);
+	if (ret)
+		return ret;
+
+	/* start the frame interval monitor */
+	ret = imx_media_fim_set_stream(priv->fim, priv->sensor, true);
+	if (ret)
+		return ret;
+
+	ret = ipu_csi_enable(priv->csi);
+	if (ret) {
+		v4l2_err(&priv->sd, "CSI enable error: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void csi_stop(struct csi_priv *priv)
+{
+	/* stop the frame interval monitor */
+	imx_media_fim_set_stream(priv->fim, priv->sensor, false);
+
+	ipu_csi_disable(priv->csi);
+}
+
+static int csi_s_stream(struct v4l2_subdev *sd, int enable)
+{
+	struct csi_priv *priv = v4l2_get_subdevdata(sd);
+	int ret = 0;
+
+	if (!priv->src_sd || !priv->sink_sd)
+		return -EPIPE;
+
+	v4l2_info(sd, "stream %s\n", enable ? "ON" : "OFF");
+
+	if (enable && !priv->stream_on)
+		ret = csi_start(priv);
+	else if (!enable && priv->stream_on)
+		csi_stop(priv);
+
+	if (!ret)
+		priv->stream_on = enable;
+	return ret;
+}
+
+static int csi_s_power(struct v4l2_subdev *sd, int on)
+{
+	struct csi_priv *priv = v4l2_get_subdevdata(sd);
+	int ret = 0;
+
+	v4l2_info(sd, "power %s\n", on ? "ON" : "OFF");
+
+	if (on != priv->power_on)
+		ret = imx_media_fim_set_power(priv->fim, on);
+
+	if (!ret)
+		priv->power_on = on;
+	return ret;
+}
+
+static int csi_link_setup(struct media_entity *entity,
+			  const struct media_pad *local,
+			  const struct media_pad *remote, u32 flags)
+{
+	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+	struct csi_priv *priv = v4l2_get_subdevdata(sd);
+	struct v4l2_subdev *remote_sd;
+
+	dev_dbg(priv->dev, "link setup %s -> %s", remote->entity->name,
+		local->entity->name);
+
+	remote_sd = media_entity_to_v4l2_subdev(remote->entity);
+
+	if (local->flags & MEDIA_PAD_FL_SINK) {
+		if (flags & MEDIA_LNK_FL_ENABLED) {
+			if (priv->src_sd)
+				return -EBUSY;
+			priv->src_sd = remote_sd;
+		} else {
+			priv->src_sd = NULL;
+			return 0;
+		}
+
+		return 0;
+	}
+
+	if (flags & MEDIA_LNK_FL_ENABLED) {
+		if (priv->sink_sd)
+			return -EBUSY;
+		priv->sink_sd = remote_sd;
+	} else {
+		priv->sink_sd = NULL;
+		return 0;
+	}
+
+	/* set CSI destination */
+	switch (remote_sd->grp_id) {
+	case IMX_MEDIA_GRP_ID_SMFC0:
+	case IMX_MEDIA_GRP_ID_SMFC1:
+	case IMX_MEDIA_GRP_ID_SMFC2:
+	case IMX_MEDIA_GRP_ID_SMFC3:
+		priv->dest = IPU_CSI_DEST_IDMAC;
+		break;
+	case IMX_MEDIA_GRP_ID_IC_PRPVF:
+		priv->dest = IPU_CSI_DEST_VDIC;
+		break;
+	case IMX_MEDIA_GRP_ID_IC_PRPENC:
+		priv->dest = IPU_CSI_DEST_IC;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int csi_link_validate(struct v4l2_subdev *sd,
+			     struct media_link *link,
+			     struct v4l2_subdev_format *source_fmt,
+			     struct v4l2_subdev_format *sink_fmt)
+{
+	struct csi_priv *priv = v4l2_get_subdevdata(sd);
+	bool is_csi2;
+	int ret;
+
+	ret = v4l2_subdev_link_validate_default(sd, link, source_fmt, sink_fmt);
+	if (ret)
+		return ret;
+
+	priv->sensor = __imx_media_find_sensor(priv->md, &priv->sd.entity);
+	if (IS_ERR(priv->sensor)) {
+		v4l2_err(&priv->sd, "no sensor attached\n");
+		ret = PTR_ERR(priv->sensor);
+		priv->sensor = NULL;
+		return ret;
+	}
+
+	ret = v4l2_subdev_call(priv->sensor->sd, video, g_mbus_config,
+			       &priv->sensor_mbus_cfg);
+	if (ret)
+		return ret;
+
+	is_csi2 = (priv->sensor_mbus_cfg.type == V4L2_MBUS_CSI2);
+
+	if (is_csi2) {
+		int vc_num = 0;
+		/*
+		 * NOTE! It seems the virtual channels from the mipi csi-2
+		 * receiver are used only for routing by the video mux's,
+		 * or for hard-wired routing to the CSI's. Once the stream
+		 * enters the CSI's however, they are treated internally
+		 * in the IPU as virtual channel 0.
+		 */
+#if 0
+		vc_num = imx_media_find_mipi_csi2_channel(priv->md,
+							  &priv->sd.entity);
+		if (vc_num < 0)
+			return vc_num;
+#endif
+		ipu_csi_set_mipi_datatype(priv->csi, vc_num,
+					  &priv->format_mbus[priv->input_pad]);
+	}
+
+	/* select either parallel or MIPI-CSI2 as input to CSI */
+	ipu_set_csi_src_mux(priv->ipu, priv->csi_id, is_csi2);
+
+	return 0;
+}
+
+static int csi_eof_isr(struct v4l2_subdev *sd, u32 status, bool *handled)
+{
+	struct csi_priv *priv = v4l2_get_subdevdata(sd);
+	struct timespec cur_ts;
+
+	ktime_get_ts(&cur_ts);
+
+	/* call frame interval monitor */
+	imx_media_fim_eof_monitor(priv->fim, &cur_ts);
+
+	return 0;
+}
+
+static int csi_try_crop(struct csi_priv *priv, struct v4l2_rect *crop)
+{
+	struct v4l2_mbus_framefmt *infmt;
+	struct imx_media_subdev *sensor;
+	v4l2_std_id std;
+	int ret;
+
+	sensor = imx_media_find_sensor(priv->md, &priv->sd.entity);
+	if (IS_ERR(sensor)) {
+		v4l2_err(&priv->sd, "no sensor attached\n");
+		return PTR_ERR(sensor);
+	}
+
+	ret = v4l2_subdev_call(sensor->sd, video, g_mbus_config,
+			       &priv->sensor_mbus_cfg);
+	if (ret)
+		return ret;
+
+	infmt = &priv->format_mbus[priv->input_pad];
+
+	crop->width = min_t(__u32, infmt->width, crop->width);
+	if (crop->left + crop->width > infmt->width)
+		crop->left = infmt->width - crop->width;
+	/* adjust crop left/width to h/w alignment restrictions */
+	crop->left &= ~0x3;
+	crop->width &= ~0x7;
+
+	/*
+	 * FIXME: not sure why yet, but on interlaced bt.656,
+	 * changing the vertical cropping causes loss of vertical
+	 * sync, so fix it to NTSC/PAL active lines. NTSC contains
+	 * 2 extra lines of active video that need to be cropped.
+	 */
+	if (priv->sensor_mbus_cfg.type == V4L2_MBUS_BT656) {
+		ret = v4l2_subdev_call(sensor->sd, video, g_std, &std);
+		if (ret)
+			return ret;
+		if (std & V4L2_STD_525_60) {
+			crop->top = 2;
+			crop->height = 480;
+		} else {
+			crop->top = 0;
+			crop->height = 576;
+		}
+	} else {
+		crop->height = min_t(__u32, infmt->height, crop->height);
+		if (crop->top + crop->height > infmt->height)
+			crop->top = infmt->height - crop->height;
+	}
+
+	return 0;
+}
+
+static int csi_get_fmt(struct v4l2_subdev *sd,
+		       struct v4l2_subdev_pad_config *cfg,
+		       struct v4l2_subdev_format *sdformat)
+{
+	struct csi_priv *priv = v4l2_get_subdevdata(sd);
+
+	if (sdformat->pad >= CSI_NUM_PADS)
+		return -EINVAL;
+
+	sdformat->format = priv->format_mbus[sdformat->pad];
+
+	return 0;
+}
+
+static int csi_set_fmt(struct v4l2_subdev *sd,
+		       struct v4l2_subdev_pad_config *cfg,
+		       struct v4l2_subdev_format *sdformat)
+{
+	struct csi_priv *priv = v4l2_get_subdevdata(sd);
+	struct v4l2_mbus_framefmt *infmt, *outfmt;
+	struct v4l2_rect crop;
+	int ret;
+
+	if (sdformat->pad >= CSI_NUM_PADS)
+		return -EINVAL;
+
+	if (priv->stream_on)
+		return -EBUSY;
+
+	infmt = &priv->format_mbus[priv->input_pad];
+	outfmt = &priv->format_mbus[priv->output_pad];
+
+	if (sdformat->pad == priv->output_pad) {
+		sdformat->format.code = infmt->code;
+		sdformat->format.field = infmt->field;
+		crop.left = priv->crop.left;
+		crop.top = priv->crop.top;
+		crop.width = sdformat->format.width;
+		crop.height = sdformat->format.height;
+		ret = csi_try_crop(priv, &crop);
+		if (ret)
+			return ret;
+		sdformat->format.width = crop.width;
+		sdformat->format.height = crop.height;
+	}
+
+	if (sdformat->which == V4L2_SUBDEV_FORMAT_TRY) {
+		cfg->try_fmt = sdformat->format;
+	} else {
+		priv->format_mbus[sdformat->pad] = sdformat->format;
+		/* Update the crop window if this is output pad  */
+		if (sdformat->pad == priv->output_pad)
+			priv->crop = crop;
+	}
+
+	return 0;
+}
+
+static int csi_get_selection(struct v4l2_subdev *sd,
+			     struct v4l2_subdev_pad_config *cfg,
+			     struct v4l2_subdev_selection *sel)
+{
+	struct csi_priv *priv = v4l2_get_subdevdata(sd);
+	struct v4l2_mbus_framefmt *infmt;
+
+	if (sel->pad != priv->output_pad)
+		return -EINVAL;
+
+	infmt = &priv->format_mbus[priv->input_pad];
+
+	switch (sel->target) {
+	case V4L2_SEL_TGT_CROP_BOUNDS:
+		sel->r.left = 0;
+		sel->r.top = 0;
+		sel->r.width = infmt->width;
+		sel->r.height = infmt->height;
+		break;
+	case V4L2_SEL_TGT_CROP:
+		sel->r = priv->crop;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int csi_set_selection(struct v4l2_subdev *sd,
+			     struct v4l2_subdev_pad_config *cfg,
+			     struct v4l2_subdev_selection *sel)
+{
+	struct csi_priv *priv = v4l2_get_subdevdata(sd);
+	struct v4l2_mbus_framefmt *outfmt;
+	int ret;
+
+	if (sel->pad != priv->output_pad ||
+	    sel->target != V4L2_SEL_TGT_CROP)
+		return -EINVAL;
+
+	if (priv->stream_on)
+		return -EBUSY;
+
+	/*
+	 * Modifying the crop rectangle always changes the format on the source
+	 * pad. If the KEEP_CONFIG flag is set, just return the current crop
+	 * rectangle.
+	 */
+	if (sel->flags & V4L2_SEL_FLAG_KEEP_CONFIG) {
+		sel->r = priv->crop;
+		if (sel->which == V4L2_SUBDEV_FORMAT_TRY)
+			cfg->try_crop = sel->r;
+		return 0;
+	}
+
+	outfmt = &priv->format_mbus[priv->output_pad];
+
+	ret = csi_try_crop(priv, &sel->r);
+	if (ret)
+		return ret;
+
+	if (sel->which == V4L2_SUBDEV_FORMAT_TRY) {
+		cfg->try_crop = sel->r;
+	} else {
+		priv->crop = sel->r;
+		/* Update the source format */
+		outfmt->width = sel->r.width;
+		outfmt->height = sel->r.height;
+	}
+
+	return 0;
+}
+
+/*
+ * retrieve our pads parsed from the OF graph by the media device
+ */
+static int csi_registered(struct v4l2_subdev *sd)
+{
+	struct csi_priv *priv = v4l2_get_subdevdata(sd);
+	struct imx_media_subdev *imxsd;
+	struct imx_media_pad *pad;
+	int i, ret;
+
+	/* get media device */
+	priv->md = dev_get_drvdata(sd->v4l2_dev->dev);
+
+	/* get handle to IPU CSI */
+	priv->csi = ipu_csi_get(priv->ipu, priv->csi_id);
+	if (IS_ERR(priv->csi)) {
+		v4l2_err(&priv->sd, "failed to get CSI %d\n", priv->csi_id);
+		return PTR_ERR(priv->csi);
+	}
+
+	imxsd = imx_media_find_subdev_by_sd(priv->md, sd);
+	if (IS_ERR(imxsd)) {
+		ret = PTR_ERR(imxsd);
+		goto put_csi;
+	}
+
+	if (imxsd->num_sink_pads != 1 || imxsd->num_src_pads != 1) {
+		ret = -EINVAL;
+		goto put_csi;
+	}
+
+	for (i = 0; i < CSI_NUM_PADS; i++) {
+		pad = &imxsd->pad[i];
+		priv->pad[i] = pad->pad;
+		if (priv->pad[i].flags & MEDIA_PAD_FL_SINK)
+			priv->input_pad = i;
+		else
+			priv->output_pad = i;
+
+		/* set a default mbus format  */
+		ret = imx_media_init_mbus_fmt(&priv->format_mbus[i],
+					      640, 480, 0, V4L2_FIELD_NONE,
+					      NULL);
+		if (ret)
+			goto put_csi;
+	}
+
+	priv->fim = imx_media_fim_init(&priv->sd);
+	if (IS_ERR(priv->fim)) {
+		ret = PTR_ERR(priv->fim);
+		goto put_csi;
+	}
+
+	ret = media_entity_pads_init(&sd->entity, CSI_NUM_PADS, priv->pad);
+	if (ret)
+		goto free_fim;
+
+	return 0;
+free_fim:
+	imx_media_fim_free(priv->fim);
+put_csi:
+	ipu_csi_put(priv->csi);
+	return ret;
+}
+
+static struct media_entity_operations csi_entity_ops = {
+	.link_setup = csi_link_setup,
+	.link_validate = v4l2_subdev_link_validate,
+};
+
+static struct v4l2_subdev_core_ops csi_core_ops = {
+	.s_power = csi_s_power,
+	.interrupt_service_routine = csi_eof_isr,
+};
+
+static struct v4l2_subdev_video_ops csi_video_ops = {
+	.s_stream = csi_s_stream,
+};
+
+static struct v4l2_subdev_pad_ops csi_pad_ops = {
+	.get_fmt = csi_get_fmt,
+	.set_fmt = csi_set_fmt,
+	.get_selection = csi_get_selection,
+	.set_selection = csi_set_selection,
+	.link_validate = csi_link_validate,
+};
+
+static struct v4l2_subdev_ops csi_subdev_ops = {
+	.core = &csi_core_ops,
+	.video = &csi_video_ops,
+	.pad = &csi_pad_ops,
+};
+
+static struct v4l2_subdev_internal_ops csi_internal_ops = {
+	.registered = csi_registered,
+};
+
+static int imx_csi_probe(struct platform_device *pdev)
+{
+	struct ipu_client_platformdata *pdata;
+	struct csi_priv *priv;
+	int ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, &priv->sd);
+	priv->dev = &pdev->dev;
+
+	/* get parent IPU */
+	priv->ipu = dev_get_drvdata(priv->dev->parent);
+
+	/* get our CSI id */
+	pdata = priv->dev->platform_data;
+	priv->csi_id = pdata->csi;
+
+	v4l2_subdev_init(&priv->sd, &csi_subdev_ops);
+	v4l2_set_subdevdata(&priv->sd, priv);
+	priv->sd.internal_ops = &csi_internal_ops;
+	priv->sd.entity.ops = &csi_entity_ops;
+	/* FIXME: this the right function? */
+	priv->sd.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
+	priv->sd.grp_id = priv->csi_id ?
+		IMX_MEDIA_GRP_ID_CSI1 : IMX_MEDIA_GRP_ID_CSI0;
+	priv->sd.dev = &pdev->dev;
+	priv->sd.owner = THIS_MODULE;
+	priv->sd.flags = V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
+	imx_media_grp_id_to_sd_name(priv->sd.name, sizeof(priv->sd.name),
+				    priv->sd.grp_id, ipu_get_num(priv->ipu));
+
+	v4l2_ctrl_handler_init(&priv->ctrl_hdlr, 0);
+	priv->sd.ctrl_handler = &priv->ctrl_hdlr;
+
+	ret = v4l2_async_register_subdev(&priv->sd);
+	if (ret)
+		goto free_ctrls;
+
+	return 0;
+free_ctrls:
+	v4l2_ctrl_handler_free(&priv->ctrl_hdlr);
+	return ret;
+}
+
+static int imx_csi_remove(struct platform_device *pdev)
+{
+	struct v4l2_subdev *sd = platform_get_drvdata(pdev);
+	struct csi_priv *priv = sd_to_dev(sd);
+
+	imx_media_fim_free(priv->fim);
+	v4l2_async_unregister_subdev(&priv->sd);
+	media_entity_cleanup(&priv->sd.entity);
+	v4l2_device_unregister_subdev(sd);
+
+	if (!IS_ERR_OR_NULL(priv->csi))
+		ipu_csi_put(priv->csi);
+
+	return 0;
+}
+
+static const struct platform_device_id imx_csi_ids[] = {
+	{ .name = "imx-ipuv3-csi" },
+	{ },
+};
+MODULE_DEVICE_TABLE(platform, imx_csi_ids);
+
+static struct platform_driver imx_csi_driver = {
+	.probe = imx_csi_probe,
+	.remove = imx_csi_remove,
+	.id_table = imx_csi_ids,
+	.driver = {
+		.name = "imx-ipuv3-csi",
+		.owner = THIS_MODULE,
+	},
+};
+module_platform_driver(imx_csi_driver);
+
+MODULE_DESCRIPTION("i.MX CSI subdev driver");
+MODULE_AUTHOR("Steve Longerbeam <steve_longerbeam@mentor.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:imx-ipuv3-csi");
-- 
2.7.4