Re: [RFC,V2,07/11] media: platform: Add Mediatek ISP P1 private control

Sakari Ailus
2019-10-02T10:56:08Z

Hi Jungo, Hans,

On Mon, May 13, 2019 at 10:46:46AM +0200, Hans Verkuil wrote:
> On 5/10/19 3:58 AM, Jungo Lin wrote:
...
> > +struct v4l2_ctrl_config mtk_cam_controls[] = {
> > + {
> > + .ops = &mtk_cam_dev_ctrl_ops,
> > + .id = V4L2_CID_PRIVATE_GET_BIN_INFO,
>
> Don't use "PRIVATE" in the name. I'd replace that with MTK to indicate
> that this is mediatek-specific. Same for the next control below.
>
> > + .name = "MTK CAM GET BIN INFO",
> > + .type = V4L2_CTRL_TYPE_INTEGER,
> > + .min = (IMG_MIN_WIDTH << 16) | IMG_MIN_HEIGHT,
> > + .max = (IMG_MAX_WIDTH << 16) | IMG_MAX_HEIGHT,
> > + .step = 1,
> > + .def = (IMG_MAX_WIDTH << 16) | IMG_MAX_HEIGHT,
> > + .flags = V4L2_CTRL_FLAG_READ_ONLY | V4L2_CTRL_FLAG_VOLATILE,
>
> Don't mix width and height. I recommend splitting this into two controls.
>
> Sakari might have an opinion on this as well.
>
> > + },
> > + {
> > + .ops = &mtk_cam_dev_ctrl_ops,
> > + .id = V4L2_CID_PRIVATE_RAW_PATH,
> > + .name = "MTK CAM RAW PATH",
> > + .type = V4L2_CTRL_TYPE_BOOLEAN,
> > + .min = 0,
> > + .max = 1,
> > + .step = 1,
> > + .def = 1,
> > + },
>
> RAW_PATH is a very vague name. If it is 0, then it is pure raw, and if it
> is 1, then it is 'processing raw'? If so, call it "Processing Raw".

Jungo: what's the purpose of

>
> Although you have to describe in the header or here what that means.
>
> Private controls should be well documented.
>
> > +};
> > +
> > +int mtk_cam_ctrl_init(struct mtk_cam_dev *cam_dev,
> > + struct v4l2_ctrl_handler *hdl)
> > +{
> > + unsigned int i;
> > +
> > + /* Initialized HW controls, allow V4L2_CID_MTK_CAM_MAX ctrls */
> > + v4l2_ctrl_handler_init(hdl, V4L2_CID_MTK_CAM_MAX);
> > + if (hdl->error) {
> > + v4l2_ctrl_handler_free(hdl);
> > + return hdl->error;
> > + }
> > +
> > + for (i = 0; i < ARRAY_SIZE(mtk_cam_controls); i++)
> > + v4l2_ctrl_new_custom(hdl, &mtk_cam_controls[i], cam_dev);
> > +
> > + dev_dbg(&cam_dev->pdev->dev, "%s done", __func__);
> > + return 0;
> > +}
> > diff --git a/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam-ctrl.h b/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam-ctrl.h
> > new file mode 100644
> > index 000000000000..74a6538c81ac
> > --- /dev/null
> > +++ b/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam-ctrl.h
> > @@ -0,0 +1,32 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (c) 2018 MediaTek Inc.
> > + * Author: Ryan Yu <ryan.yu@mediatek.com>
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2 as
> > + * published by the Free Software Foundation.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > + * GNU General Public License for more details.
> > + */
> > +
> > +#ifndef __MTK_CAM_CTRL_H__
> > +#define __MTK_CAM_CTRL_H__
> > +
> > +#include <media/v4l2-ctrls.h>
> > +
> > +#define V4L2_CID_MTK_CAM_PRIVATE_CAM V4L2_CID_USER_MTK_CAM_BASE
> > +#define V4L2_CID_PRIVATE_GET_BIN_INFO \
> > + (V4L2_CID_MTK_CAM_PRIVATE_CAM + 1)
> > +#define V4L2_CID_PRIVATE_RAW_PATH \
> > + (V4L2_CID_MTK_CAM_PRIVATE_CAM + 2)
>
> These last two defines can be on a single line.
>
> They need to be documented in the header.
>
> > +
> > +#define V4L2_CID_MTK_CAM_MAX 16
> > +
> > +int mtk_cam_ctrl_init(struct mtk_cam_dev *cam_dev,
> > + struct v4l2_ctrl_handler *hdl);
> > +
> > +#endif /* __MTK_CAM_CTRL_H__ */
> > diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
> > index 06479f2fb3ae..cbe8f5f7782b 100644
> > --- a/include/uapi/linux/v4l2-controls.h
> > +++ b/include/uapi/linux/v4l2-controls.h
> > @@ -192,6 +192,10 @@ enum v4l2_colorfx {
> > * We reserve 16 controls for this driver. */
> > #define V4L2_CID_USER_IMX_BASE (V4L2_CID_USER_BASE + 0x10b0)
> >
> > +/* The base for the mediatek ISP Pass 1 driver controls */
> > +/* We reserve 16 controls for this driver. */
> > +#define V4L2_CID_USER_MTK_CAM_BASE (V4L2_CID_USER_BASE + 0x10c0)
> > +
> > /* MPEG-class control IDs */
> > /* The MPEG controls are applicable to all codec controls
> > * and the 'MPEG' part of the define is historical */
> >
>
> Regards,
>
> Hans

--
Sakari Ailus
sakari.ailus@linux.intel.com