On Wed, Oct 19, 2016 at 11:53:10AM +0200, Hans de Goede wrote: > > > If all the hardware allows you to-do is set / read the pin, you > > > could write a gpio-chip driver for it, and then attach a generic > > > cec-over-gpio driver to that, that seems like a better idea then > > > an Allwinner specific bit-bang driver. > > > > That might not be easy to do. The CEC line is a dedicated pin on the SoC, > > leading to the HDMI controller, much like the HDMI DDC lines. And the > > control > > bits are in the middle of the HDMI register space. > > > > Doing a one-line GPIO controller for that pin should work, though it's a > > really convoluted approach.
+1 > If we're going to spend time writing a bit-bang cec driver using > timers we should IMHO really do this through a gpio indirection so > that the entire bit-bang code can be shared. Well, it might not be even shared. Someone hooking it on a GPIO will have an interrupt on that GPIO, and that will change the polling logic significantly. > As for this being convoluted, it does not need to be that bad. I > think you're thinking too much along the lines of doing a > stand-alone gpio driver + regmap or some such to access the > register. But we can just have the hdmi encoder driver register a > gpio_chip, without doing 2 separate drivers, and then the code > should be pretty clean. You'd still have to tie it to the CEC stuff. And really, it's not a GPIO, but more just an O and an I ;) Maxime -- Maxime Ripard, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
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