Re: [PATCH v2 11/19] media: imx: Add CSI subdev driver

From: Vladimir Zapolskiy
Date: Wed Jan 04 2017 - 08:44:51 EST


On 01/03/2017 10:57 PM, Steve Longerbeam wrote:
> This is a media entity subdevice for the i.MX Camera
> Serial Interface module.
>
> Signed-off-by: Steve Longerbeam <steve_longerbeam@xxxxxxxxxx>
> ---

[snip]

> 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>

Please add the headers alphabetically ordered.

> +#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;

if (ret)
v4l2_err(&priv->sd, "CSI enable error: %d\n", ret);

return ret;

> +}
> +
> +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;

You can remove the return above.

> + }
> +
> + return 0;
> + }
> +

[snip]

> +
> +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;

This is a functionally equal and simplified version:

if (ret)
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,

Please drop .owner.

> + },
> +};
> +module_platform_driver(imx_csi_driver);
> +
> +MODULE_DESCRIPTION("i.MX CSI subdev driver");
> +MODULE_AUTHOR("Steve Longerbeam <steve_longerbeam@xxxxxxxxxx>");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:imx-ipuv3-csi");
>

--
With best wishes,
Vladimir