| Message ID | 20200416104052.2643098-16-jacopo+renesas@jmondi.org (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Kieran Bingham |
| Headers | show |
| Series | GMSL: max9286-v8-rc1 + RDAMC20-v8 | expand |
Hi Jacopo, On 16/04/2020 11:40, Jacopo Mondi wrote: > From: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> > > Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> > > --- > 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. * > + */ > + max9286_write(priv, 0x63, 0); > + max9286_write(priv, 0x64, 0); > + > /* > * Wait for 2ms to allow the link to resynchronize after the > * configuration change. >
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@ideasonboard.com> > > > > Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> > > > > --- > > 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. > > > + */ > > + max9286_write(priv, 0x63, 0); > > + max9286_write(priv, 0x64, 0); > > + > > /* > > * Wait for 2ms to allow the link to resynchronize after the > > * configuration change. > > >
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@ideasonboard.com> >>> >>> Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> >>> >>> --- >>> 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. >>> >>
Hi Kieran, On Thu, Apr 16, 2020 at 12:31:32PM +0100, Kieran Bingham wrote: > 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@ideasonboard.com> > >>> > >>> Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> > >>> > >>> --- > >>> 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... In that case yes, I was concerned about the "reserved bits", but please go ahead and add that comment. > > > > >> > >>> + */ > >>> + max9286_write(priv, 0x63, 0); > >>> + max9286_write(priv, 0x64, 0); > >>> + > >>> /* > >>> * Wait for 2ms to allow the link to resynchronize after the > >>> * configuration change. > >>> > >> >
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. + */ + max9286_write(priv, 0x63, 0); + max9286_write(priv, 0x64, 0); + /* * Wait for 2ms to allow the link to resynchronize after the * configuration change.