>> However, hi8435 driver historically was coded using inverted values >> passed to gpiolib calls. And there are setups in the wild with device >> trees containing GPIO_ACTIVE_HIGH that I'd prefer not breaking. >> >> To solve, I submitted a patch on hi8435 driver that changes to _raw() >> gpio calls (thus making it independent of what is written in device >> tree), and want [future] device trees not to contain explicitly written >> gpio polarity. > > So maybe add another #define, GPIO_ACTIVE_IGNORED, to make it clear > that it does not matter what value you put there, it is ignored. "Crap origin" here is that in vast majority of cases, polarity is per-chip, not per-chip-use, knowledge. And proper location for per-chip knowledge is chip's driver. Moving this knowledge to per-chip-use location in device trees only provides a source for errors, with little gain. Vladimir Barinov mentions possibility that signal can be inverted by board between gpio provider and chip's pin ... but do we have at least one practical case of this? And if we even do, it's quite uncommon, and something special should be required in device tree for these special cases and not for "normal" cases. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
