On 16/04/2020 12:31, Jacopo Mondi wrote: > Hi Kieran, > > On Thu, Apr 16, 2020 at 11:50:07AM +0100, Kieran Bingham wrote: >> Hi Jacopo, >> >> On 16/04/2020 11:40, Jacopo Mondi wrote: >>> From: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx> >>> >>> Signed-off-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx> >>> >>> --- >>> v2: >>> [Jacopo] >>> - Write register 0x63 and 0x64 directly as going through the function >>> breaks RDACM21 operations >>> --- >>> drivers/media/i2c/max9286.c | 12 ++++++++++++ >>> 1 file changed, 12 insertions(+) >>> >>> diff --git a/drivers/media/i2c/max9286.c b/drivers/media/i2c/max9286.c >>> index 3ef74ba10074..e0c637d4a7de 100644 >>> --- a/drivers/media/i2c/max9286.c >>> +++ b/drivers/media/i2c/max9286.c >>> @@ -966,6 +966,18 @@ static int max9286_setup(struct max9286_priv *priv) >>> max9286_write(priv, 0x0c, MAX9286_HVEN | MAX9286_INVVS | >>> MAX9286_HVSRC_D14); >>> >>> + /* >>> + * The overlap window seems to provide additional validation by tracking >>> + * the delay between vsync and frame sync, generating an error if the >>> + * delay is bigger than the programmed window, though it's not yet clear >>> + * what value should be set. >>> + * >>> + * As it's an optional value and can be disabled, we do so by setting >>> + * a 0 overlap value. >> >> Are you happy to add the following as part of the removal of the function? >> >> * >> * The overlap window is a 13 bit value, and register 0x64 is >> * shared with ENFSINLAST in BIT(5) which is also set zero. >> * > > Not sure, as I noticed failres for RDACM21 when not writing the > supposidely reserved bits. > > As we blindly write the full registers I would leave details out until > we figure out what's happening. But that's precisely why I think we should document it :-) Otherwise - some other person could hit this issue in a different way... > >> >>> + */ >>> + max9286_write(priv, 0x63, 0); >>> + max9286_write(priv, 0x64, 0); >>> + >>> /* >>> * Wait for 2ms to allow the link to resynchronize after the >>> * configuration change. >>> >>
