On 6/27/21 4:49 AM, Linus Walleij wrote: > On Sat, Jun 26, 2021 at 1:48 AM Dipen Patel <dipenp@xxxxxxxxxx> wrote: > > Just a quick question about this: > >> + GPIO_V2_LINE_FLAG_EVENT_CLOCK_HARDWARE | \ > Is the usage intended to be such that since hardware timestamp > can not be guaranteed we need to ask for it and fail and if that > fails maybe the software wants to fall back to the realtime or > common timestamp? > > I'm thinking from the view of libgpiod or similar apps that abstract > this and they will be "I want to use hardware timestamps if and > only if it is available, otherwise I want to use this other timestamp" > or is that use case uncommon, such that either you know exactly > what you want or you should not be messing with hardware > timestamps? The way currently is implemented, if you have requested FLAG_EVENT_CLOCK_HARDWARE and it fails, control will return to userspace with an error. There is no fallback. > > Yours, > Linus Walleij