Hi Sakari,
On Thu, Jan 07, 2021 at 12:59:24AM +0200, Sakari Ailus wrote:
> 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);
>
> Could you instead use v4l2_get_link_freq()?
>
> I guess we're also moving to the LINK_FREQ control to tell this.
I've developed this patch before we discussed moving to LINQ_FREQ :-)
I'll fix this in v2.
> > + 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;
>
> Much better, thank you!
--
Regards,
Laurent Pinchart
