Hi Ricardo, Thank you for the patch. On Thu, May 14, 2020 at 04:36:12PM +0200, Ricardo Cañuelo wrote: > The tfp410 has a data de-skew feature that allows the user to compensate > the skew between IDCK and the pixel data and control signals. > > In the driver, the setup and hold times are calculated from the de-skew > value. This retrieves the deskew value from the DT using the proper > datatype and range check as described by the binding (u32 from 0 to 7) > and fixes the calculation of the setup and hold times. How about mentioning that the fix results from a change in the DT bindings ? Otherwise it sounds it was a bug in the driver. I would also mention that the patch fixes the min() calculation, which was clearly wrong. I think I would have split this in two patches. With this addressed, Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > Signed-off-by: Ricardo Cañuelo <ricardo.canuelo@xxxxxxxxxxxxx> > --- > drivers/gpu/drm/bridge/ti-tfp410.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/bridge/ti-tfp410.c b/drivers/gpu/drm/bridge/ti-tfp410.c > index e3eb6364c0f7..21d99b4ea0c9 100644 > --- a/drivers/gpu/drm/bridge/ti-tfp410.c > +++ b/drivers/gpu/drm/bridge/ti-tfp410.c > @@ -220,7 +220,7 @@ static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c) > struct device_node *ep; > u32 pclk_sample = 0; > u32 bus_width = 24; > - s32 deskew = 0; > + u32 deskew = 0; > > /* Start with defaults. */ > *timings = tfp410_default_timings; > @@ -274,12 +274,12 @@ static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c) > } > > /* Get the setup and hold time from vendor-specific properties. */ > - of_property_read_u32(dvi->dev->of_node, "ti,deskew", (u32 *)&deskew); > - if (deskew < -4 || deskew > 3) > + of_property_read_u32(dvi->dev->of_node, "ti,deskew", &deskew); > + if (deskew > 7) > return -EINVAL; > > - timings->setup_time_ps = min(0, 1200 - 350 * deskew); > - timings->hold_time_ps = min(0, 1300 + 350 * deskew); > + timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4); > + timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4)); > > return 0; > } -- Regards, Laurent Pinchart
