[U-Boot] [linux-sunxi] Re: [PATCH 3/3] sunxi: video: Add H3/H5 TV out driver

[Jernej Škrabec]

Hi,

Dne ponedeljek, 15. maj 2017 ob 08:31:22 CEST je Maxime Ripard napisal(a):
> On Sat, May 13, 2017 at 11:14:00PM +0800, Chen-Yu Tsai wrote:
> > >>> +static int sunxi_tve_get_plug_in_status(void)
> > >>> +{
> > >>> +       struct sunxi_tve_reg * const tve =
> > >>> +               (struct sunxi_tve_reg *)SUNXI_TVE0_BASE;
> > >>> +       u32 status;
> > >>> +
> > >>> +       status = readl(&tve->auto_detect_status) &
> > >>> +               SUNXI_TVE_AUTO_DETECT_STATUS_MASK(0);
> > >>> +
> > >>> +       return status == SUNXI_TVE_AUTO_DETECT_STATUS_CONNECTED;
> > > 
> > > So TVE is now capable of hpd checking, right?
> > > 
> > > Is is a feature that exists in A10/A13/A20 or is it new in H3?
> > 
> > AFAIK this is also available in the earlier SoCs.
> > Maxime mentioned that it was unreliable though.
> 
> This was supposed to be there, but those registers were
> undocumented. It would be nice to try to see if it works.

AFAIK, H3 and newer SoCs with TV out have two additional registers for hot 
plug detection. Here are named SUNXI_TVE_AUTO_DETECT_CFG0 and 
SUNXI_TVE_AUTO_DETECT_CFG1 and they are somewhat explained in R40 manual.

I'm not sure if this changes reliability a lot or not.

Best regards,
Jernej