Hi Xavier,
On 30/07/2022 12:24, Xavier Roumegue wrote:
> Add a V4L2 mem-to-mem driver for the Vivante DW100 Dewarp Processor IP
> core found on i.MX8MP SoC.
>
> The processor core applies a programmable geometrical transformation on
> input images to correct distorsion introduced by lenses.
> The transformation function is exposed as a grid map with 16x16 pixel
> macroblocks indexed using X, Y vertex coordinates.
>
> The dewarping map can be set from application through a dedicated v4l2
> control. If not set or invalid, the driver computes an identity map
> prior to starting the processing engine.
>
> The driver supports scaling, cropping and pixel format conversion.
>
> Signed-off-by: Xavier Roumegue <xavier.roumegue@xxxxxxxxxxx>
> Reviewed-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxxxxxxxxx>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> ---
> drivers/media/platform/nxp/Kconfig | 1 +
> drivers/media/platform/nxp/Makefile | 1 +
> drivers/media/platform/nxp/dw100/Kconfig | 17 +
> drivers/media/platform/nxp/dw100/Makefile | 3 +
> drivers/media/platform/nxp/dw100/dw100.c | 1712 +++++++++++++++++
> drivers/media/platform/nxp/dw100/dw100_regs.h | 117 ++
> 6 files changed, 1851 insertions(+)
> create mode 100644 drivers/media/platform/nxp/dw100/Kconfig
> create mode 100644 drivers/media/platform/nxp/dw100/Makefile
> create mode 100644 drivers/media/platform/nxp/dw100/dw100.c
> create mode 100644 drivers/media/platform/nxp/dw100/dw100_regs.h
>
<snip>
> +/*
> + * Initialize the dewarping map with an identity mapping.
> + *
> + * A 16 pixels cell size grid is mapped on the destination image.
> + * The last cells width/height might be lesser than 16 if the destination image
> + * width/height is not divisible by 16. This dewarping grid map specifies the
> + * source image pixel location (x, y) on each grid intersection point.
> + * Bilinear interpolation is used to compute inner cell points locations.
> + *
> + * The coordinates are saved in UQ12.4 fixed point format.
> + */
> +static void dw100_ctrl_dewarping_map_init(const struct v4l2_ctrl *ctrl,
> + u32 from_idx, u32 elems,
> + union v4l2_ctrl_ptr ptr)
> +{
> + struct dw100_ctx *ctx =
> + container_of(ctrl->handler, struct dw100_ctx, hdl);
> +
> + u32 sw, sh, dw, dh, mw, mh, i, j;
> + u16 qx, qy, qdx, qdy, qsh, qsw;
> + u32 *map = ctrl->p_cur.p_u32;
> +
> + sw = ctx->q_data[DW100_QUEUE_SRC].pix_fmt.width;
> + dw = ctx->q_data[DW100_QUEUE_DST].pix_fmt.width;
> + sh = ctx->q_data[DW100_QUEUE_SRC].pix_fmt.height;
> + dh = ctx->q_data[DW100_QUEUE_DST].pix_fmt.height;
> +
> + mw = dw100_get_n_vertices_from_length(dw);
> + mh = dw100_get_n_vertices_from_length(dh);
Note that ctrl->dims[] contains the array dimensions: use that rather than
calculating from dw/dh since using dims[] is more robust.
> +
> + qsw = dw100_map_convert_to_uq12_4(sw);
> + qsh = dw100_map_convert_to_uq12_4(sh);
> + qdx = qsw / (mw - 1);
> + qdy = qsh / (mh - 1);
> +
> + ctx->map_width = mw;
> + ctx->map_height = mh;
> + ctx->map_size = mh * mw * sizeof(u32);
> +
> + for (i = 0, qy = 0; i < mh; i++, qy += qdy) {
This isn't correct: you actually start from 'from_idx', which is almost always 0,
except if userspace only sets the first N elements of an array, in that case
those N elements are copied to the control array and the remainder is initialized.
I admit that it doesn't make much sense in this particular case, but you still
need to take it into account.
I also would rename i and j to y and x, that makes more sense here.
> + if (qy > qsh)
> + qy = qsh;
> + for (j = 0, qx = 0; j < mw; j++, qx += qdx) {
> + if (qx > qsw)
> + qx = qsw;
> + *map++ = dw100_map_format_coordinates(qx, qy);
> + }
> + }
> +
> + ctx->user_map_is_set = false;
> +}
Regards,
Hans
> +
> +static const struct v4l2_ctrl_type_ops dw100_ctrl_type_ops = {
> + .init = dw100_ctrl_dewarping_map_init,
> + .validate = v4l2_ctrl_type_op_validate,
> + .log = v4l2_ctrl_type_op_log,
> + .equal = v4l2_ctrl_type_op_equal,
> +};
> +
> +static const struct v4l2_ctrl_config controls[] = {
> + [DW100_CTRL_DEWARPING_MAP] = {
> + .ops = &dw100_ctrl_ops,
> + .type_ops = &dw100_ctrl_type_ops,
> + .id = V4L2_CID_DW100_DEWARPING_16x16_VERTEX_MAP,
> + .name = "Dewarping Vertex Map",
> + .type = V4L2_CTRL_TYPE_U32,
> + .min = 0x00000000,
> + .max = 0xffffffff,
> + .step = 1,
> + .def = 0,
> + .dims = { DW100_DEF_LUT_W, DW100_DEF_LUT_H },
> + },
> +};
Regards,
Hans
