RE: Delay between stop condition and start condition

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



> Subject: Re: Delay between stop condition and start condition
>
>
> > The passthrough mode is not default, it gets activated by the driver so that
> > drm_get_edid can then fetch the EDID. One other nasty thing is that to end the conversation
> > with the monitor you are supposed to write 0x00 to register 0x1a of the HDMI transmitter,
> > which means the SoC puts address 0x39 on the bus, but the HDMI transmitter lets that
> > through, the monitor NACKs the address (because its address is 0x50), and from that
> > moment on the control is back with the HDMI transmitter.
> > Unfortunately I don't have any other slave on the same bus, but I wonder what happens
> > if someone else tries to use the same bus while the pass through mode is operating...
>
> Wouldn't all this really speak for an i2c gate? Do all enablement stuff
> in select(), all disablement stuff in deselect(), and make sure
> deselect() is called after every transfer. That would mean the
> passthrough is only active when the EDID eeprom is accessed. Would that
> work? Given the above, it looks quite sane to do it like that in order
> to avoid side-effects of the open passthrough.

It sounds like an i2c gate could fit the purpose. I'll give it a shot!

Thank you All!

Fab




Renesas Electronics Europe Ltd, Dukes Meadow, Millboard Road, Bourne End, Buckinghamshire, SL8 5FH, UK. Registered in England & Wales under Registered No. 04586709.




[Index of Archives]     [Linux GPIO]     [Linux SPI]     [Linux Hardward Monitoring]     [LM Sensors]     [Linux USB Devel]     [Linux Media]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux