Hi Jose, On Friday 06 Jan 2017 10:07:03 Jose Abreu wrote: > Hi Laurent, > > Sorry for the delayed answer but I am quite busy at the moment. No worries, your help is really appreciated. > On 06-01-2017 01:48, Laurent Pinchart wrote: > > [snip] > > >>>> The TX_READY signal is documented in the i.MX6 datasheet as being a PHY > >>>> output signal, but there seems to be no HDMI TX register from which its > >>>> state can be read. Do I need to poll the HDMI_PHY_PTRPT_ENBL register > >>>> through I2C ? How long is the PHY expected to take to set TX_READY to 0 > >>>> ? > >>> > >>> TX_READY can be read from register 0x1A of phy, BIT(2) (through > >>> I2C). > >> > >> That's what I thought, I'll poll that then. Do you have any idea how long > >> it's supposed to take, to set an appropriate timeout ? > > For 3d tx phy and for 25 MHz input reference clock the power-up > time is ~1ms, there is no data in the docs to power-down time but > it should be similar. Reference clock value is board dependent > and the minimum value for HDMI shall be 13.5MHz. > > > On i.MX6 (3D TX PHY) register 0x1a reads as 0x0007 before powering down > > the PHY (by deasserting TXPWRON) and as 0x0000 immediately after. On > > RK3288 (MHL PHY) the register reads as 0x0207 and as 0x0000 immediately > > after deasserting TXPWRON. It seems that one I2C read is a sufficient > > delay for TX_READY to go low. > > > >>> Not sure if same offset for all phys though. > >> > >> Most probably not, it would be too easy :-) I'll investigate (which will > >> likely include lots of guesswork). If you can find any information about > >> that (and especially about the MHL and HDMI 2.0 PHYs) that would be very > >> appreciated, as I don't have access to any documentation that mentions a > >> TX_READY bit for those. > > > > I haven't tested the HDMI 2.0 PHY yet, but I'd be surprised if the > > TX_READY bit was in the same register at the same position. > > The info I got the register offset is from an HDMI 2.0 phy :) That's good news :-) > Notice that there are a lot of phy versions and some of them > (used in dw-hdmi) maybe customized, I don't think I have access > to that custom phys documentation. I think we will eventually have to implement PHY-specific power up and power down sequences, but for now a common sequence should work. > Please test the HDMI 2.0 phy and check if the register is the same, it > should be. I did, and it is \o/ I'll send patches. > In the meantime it would really be helpful if some of the developers > that used dw-hdmi supplied this info about the registers as they > should know exactly what phy was used. I will ask internally for the R-Car H3 SoC. -- Regards, Laurent Pinchart
