On Wed, Jul 26, 2017 at 11:23 AM, Lee Jones <lee.jones@xxxxxxxxxx> wrote: > On Tue, 25 Jul 2017, Andy Shevchenko wrote: >> On Tue, Jul 25, 2017 at 12:10 PM, Lee Jones <lee.jones@xxxxxxxxxx> wrote: >> I briefly checked few ->read() and ->write() implementations and >> didn't find any evidence of positive numbers that can be returned. >> Documentation (kernel doc) doesn't shed a light on that. So, to me it >> sounds unspecified. >> >> So, for now (until documentation will be fixed) I would rely on >> if (ret < 0) > > It's not unspecified. The regmap methods call into regcache_write(), > where the kerneldoc is clear. drivers/base/regmap/regcache.c:266 " * Return a negative value on failure, 0 on success." I can hardly find this any cleaner than "unspecified". > Perhaps we can also change the regmap > kerneldoc headers too to match, which might lessen the disparity. I'm not familiar with the guts of regmap API, so, I would stick with if (ret < 0) for now until documentation specifies positive return values. -- With Best Regards, Andy Shevchenko -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html