Tomi, could you push this through drm-misc ? On Wed, Feb 28, 2024 at 06:22:25PM +0200, Laurent Pinchart wrote: > Hello Rohit, > > Thank you for the patch. > > On Fri, Feb 16, 2024 at 04:40:43AM -0800, Rohit Visavalia wrote: > > Assert DisplayPort reset signal before deasserting, > > it is to clear out any registers programmed before booting kernel. > > > > Signed-off-by: Rohit Visavalia <[email protected]> > > --- > > drivers/gpu/drm/xlnx/zynqmp_dp.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/drivers/gpu/drm/xlnx/zynqmp_dp.c > > b/drivers/gpu/drm/xlnx/zynqmp_dp.c > > index 1846c4971fd8..5a40aa1d4283 100644 > > --- a/drivers/gpu/drm/xlnx/zynqmp_dp.c > > +++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c > > @@ -1714,6 +1714,10 @@ int zynqmp_dp_probe(struct zynqmp_dpsub *dpsub) > > goto err_free; > > } > > > > + ret = zynqmp_dp_reset(dp, true); > > + if (ret < 0) > > + return ret; > > + > > This looks fine to me, so > > Reviewed-by: Laurent Pinchart <[email protected]> > > However, looking at zynqmp_dp_reset(), we have > > static int zynqmp_dp_reset(struct zynqmp_dp *dp, bool assert) > { > unsigned long timeout; > > if (assert) > reset_control_assert(dp->reset); > else > reset_control_deassert(dp->reset); > > /* Wait for the (de)assert to complete. */ > timeout = jiffies + msecs_to_jiffies(RST_TIMEOUT_MS); > while (!time_after_eq(jiffies, timeout)) { > bool status = !!reset_control_status(dp->reset); > > if (assert == status) > return 0; > > cpu_relax(); > } > > dev_err(dp->dev, "reset %s timeout\n", assert ? "assert" : "deassert"); > return -ETIMEDOUT; > } > > That doesn't seem quite right. Aren't reset_control_assert() and > reset_control_deassert() supposed to be synchronous ? If so there should > be no need to wait, and if there's a need to wait, it could be a bug in > the reset controller driver. This should be fixed, and then the code in > probe could be replaced with a call to reset_control_reset(). > > > ret = zynqmp_dp_reset(dp, false); > > if (ret < 0) > > goto err_free;
-- Regards, Laurent Pinchart
