On 2018-07-20 12:57, Arnd Bergmann wrote: > * What I understand from reading i2c-demux-pinctrl.c, a slave device > will only ever be observable from one master at a time, when you > switch over, all children get removed on one master and added to > the other one, to be probed again by their respective drivers. > I can see this as a useful feature on i3c as well, in particular to > deal with the situation where we have i2c slaves connected to a > pinmux that can switch them between an i3c master and an > i2c-only master (possibly a gpio based one). That particular use > case however doesn't seem to fix well in the current code, which > is structure around i3c buses. It's pretty easy to come up with examples where this reprobing is not desirable at all. E.g. if one of the involved I2C devices is a HDMI encoder (I have a TDA19988 here) sitting in the middle of the graphics pipeline. Blink-blink on the screen because some *other* unrelated device needed to be accessed by an alternative master. Not pretty. (No, I don't suffer from this since I don't need the demuxer. Which is fortunate. This was just an example, I'm sure there are others.) Cheers, Peter -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
