On Tue, Jan 05, 2021 at 05:28:45PM +0200, Laurent Pinchart wrote:
> The Ths_settle timing parameter depends solely on the pixel rate of the
> source. Calculate it at runtime instead of requiring it to be specified
> in the device tree.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> ---
> drivers/staging/media/imx/imx7-mipi-csis.c | 65 ++++++++++++++++++----
> 1 file changed, 53 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/staging/media/imx/imx7-mipi-csis.c b/drivers/staging/media/imx/imx7-mipi-csis.c
> index 3c68ee8b2a59..c83450ac37fa 100644
> --- a/drivers/staging/media/imx/imx7-mipi-csis.c
> +++ b/drivers/staging/media/imx/imx7-mipi-csis.c
> @@ -24,6 +24,7 @@
> #include <linux/reset.h>
> #include <linux/spinlock.h>
>
> +#include <media/v4l2-ctrls.h>
> #include <media/v4l2-device.h>
> #include <media/v4l2-fwnode.h>
> #include <media/v4l2-mc.h>
> @@ -233,7 +234,11 @@ struct csi_state {
> struct media_pad pads[CSIS_PADS_NUM];
> struct v4l2_subdev mipi_sd;
> struct v4l2_async_notifier notifier;
> - struct v4l2_subdev *src_sd;
> +
> + struct {
> + struct v4l2_subdev *sd;
> + struct v4l2_ctrl *pixel_rate;
> + } src;
>
> u8 index;
> struct platform_device *pdev;
> @@ -482,6 +487,31 @@ static void __mipi_csis_set_format(struct csi_state *state)
> mipi_csis_write(state, MIPI_CSIS_ISPRESOL_CH0, val);
> }
>
> +static int mipi_csis_calculate_params(struct csi_state *state)
> +{
> + u64 pixel_rate;
> + u32 lane_rate;
> +
> + /* Calculate the line rate from the pixel rate. */
> + pixel_rate = v4l2_ctrl_g_ctrl_int64(state->src.pixel_rate);
> + lane_rate = div_u64(pixel_rate, state->bus.num_data_lanes)
> + * state->csis_fmt->width;
> + if (lane_rate < 80000000 || lane_rate > 1500000000) {
> + dev_dbg(state->dev, "Out-of-bound lane rate %u\n", lane_rate);
> + return -EINVAL;
> + }
> +
> + /*
> + * The HSSETTLE counter value is document in a table, but can also
> + * easily be calculated.
> + */
> + state->hs_settle = (lane_rate - 5000000) / 45000000;
> + dev_dbg(state->dev, "pixel rate %llu, lane rate %u, Ths_settle %u\n",
> + pixel_rate, lane_rate, state->hs_settle);
> +
> + return 0;
> +}
> +
> static void mipi_csis_set_params(struct csi_state *state)
> {
> int lanes = state->bus.num_data_lanes;
> @@ -608,16 +638,20 @@ static void mipi_csis_log_counters(struct csi_state *state, bool non_errors)
> static int mipi_csis_s_stream(struct v4l2_subdev *mipi_sd, int enable)
> {
> struct csi_state *state = mipi_sd_to_csis_state(mipi_sd);
> - int ret = 0;
> + int ret;
>
> if (enable) {
> + ret = mipi_csis_calculate_params(state);
> + if (ret < 0)
> + return ret;
> +
> mipi_csis_clear_counters(state);
> ret = pm_runtime_get_sync(&state->pdev->dev);
> if (ret < 0) {
> pm_runtime_put_noidle(&state->pdev->dev);
> return ret;
> }
> - ret = v4l2_subdev_call(state->src_sd, core, s_power, 1);
> + ret = v4l2_subdev_call(state->src.sd, core, s_power, 1);
> if (ret < 0 && ret != -ENOIOCTLCMD)
> return ret;
> }
> @@ -630,7 +664,7 @@ static int mipi_csis_s_stream(struct v4l2_subdev *mipi_sd, int enable)
> }
>
> mipi_csis_start_stream(state);
> - ret = v4l2_subdev_call(state->src_sd, video, s_stream, 1);
> + ret = v4l2_subdev_call(state->src.sd, video, s_stream, 1);
> if (ret < 0)
> goto unlock;
>
> @@ -638,8 +672,8 @@ static int mipi_csis_s_stream(struct v4l2_subdev *mipi_sd, int enable)
>
> state->flags |= ST_STREAMING;
> } else {
> - v4l2_subdev_call(state->src_sd, video, s_stream, 0);
> - ret = v4l2_subdev_call(state->src_sd, core, s_power, 0);
> + v4l2_subdev_call(state->src.sd, video, s_stream, 0);
> + ret = v4l2_subdev_call(state->src.sd, core, s_power, 0);
> if (ret == -ENOIOCTLCMD)
> ret = 0;
> mipi_csis_stop_stream(state);
> @@ -677,14 +711,24 @@ static int mipi_csis_link_setup(struct media_entity *entity,
> mutex_lock(&state->lock);
>
> if (flags & MEDIA_LNK_FL_ENABLED) {
> - if (state->src_sd) {
> + if (state->src.sd) {
> ret = -EBUSY;
> goto out;
> }
>
> - state->src_sd = remote_sd;
> + state->src.pixel_rate = v4l2_ctrl_find(remote_sd->ctrl_handler,
> + V4L2_CID_PIXEL_RATE);
> + if (!state->src.pixel_rate) {
> + dev_err(state->dev,
> + "source %s has no pixel rate control\n",
> + remote_sd->name);
> + return -EINVAL;
This needs to goto out to release lock.
------
Cheers,
Rui
> + }
> +
> + state->src.sd = remote_sd;
> } else {
> - state->src_sd = NULL;
> + state->src.pixel_rate = NULL;
> + state->src.sd = NULL;
> }
>
> out:
> @@ -943,9 +987,6 @@ static int mipi_csis_parse_dt(struct platform_device *pdev,
> if (IS_ERR(state->mrst))
> return PTR_ERR(state->mrst);
>
> - /* Get MIPI CSI-2 bus configuration from the endpoint node. */
> - of_property_read_u32(node, "fsl,csis-hs-settle", &state->hs_settle);
> -
> return 0;
> }
>
> --
> Regards,
>
> Laurent Pinchart
>
