On Thu, 15 Nov 2018 11:13:52 +0100 Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: > On Tue, Nov 6, 2018 at 12:52 PM Fabrizio Castro > <fabrizio.castro@xxxxxxxxxxxxxx> wrote: > > > While adding SiI9022A support to the iwg23s board, it came > > up that when the HDMI transmitter is in pass through mode the > > device is not compliant with the I2C specification anymore, > > as it requires a far bigger tbuf, due to a delay the HDMI > > transmitter is adding when relaying the STOP condition on the > > monitor i2c side of things. > > > > When not providing an appropriate delay after the STOP condition > > the i2c bus would get stuck. Also, any other traffic on the bus > > while talking to the monitor may cause the transaction to fail > > or even cause issues with the i2c bus as well. > > > > I2c-gates seemed to reach consent as a possible way to address > > these issues, and as such this patch is implementing a solution > > based on that. Since others are clearly relying on the current > > implementation of the driver, this patch won't require any DT > > changes. > > > > Since we don't want any interference during the DDC Bus > > Request/Grant procedure and while talking to the monitor, we > > have to use the adapter locking primitives rather than the > > i2c-mux locking primitives. > > > > Signed-off-by: Fabrizio Castro <fabrizio.castro@xxxxxxxxxxxxxx> > > > > --- > > v2->v3: > > * Incorporated comments from Boris Brezillon and Peter Rosin > > Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx> > > Do you need help to apply this to drm-misc or do you > have commit access? I can do it if needed.
