On Thu, Jul 20, 2023 at 10:05 AM Kent Gibson <warthog618@xxxxxxxxx> wrote: > > On Thu, Jul 20, 2023 at 09:59:00AM +0200, Bartosz Golaszewski wrote: > > On Thu, Jul 20, 2023 at 5:27 AM Kent Gibson <warthog618@xxxxxxxxx> wrote: > > > > > > On Wed, Jul 19, 2023 at 09:20:52PM +0200, Bartosz Golaszewski wrote: > > > > From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx> > > > > > > > > While working on the DBus API, it occurred to me that while we can obtain > > > > the list of requested offsets from a line request, this information lacks > > > > context if we cannot get any information about the parent chip on which > > > > the request was made. > > > > > > > > We cannot reference the chip in any way as its lifetime is disconnected > > > > from the request but we can at least provide the path to the character > > > > device used to open it as a way of providing some context for the offsets. > > > > > > > > > > No problem with this conceptually, the only question I have is which > > > one of these should be stored: > > > - requested path e.g. 'a_symlink_to_my_favorite_chip' > > > - canonicalised path e.g. '/dev/gpiochip0' > > > - chip name e.g. 'gpiochip0' > > > - chip number e.g. 0 > > > > > > In this patch we get the requested path, right? > > > > > > > Yes, I think we should just use whatever filesystem path was used to > > create the chip as it would be the one allowing the caller to reopen > > the same chip. > > > > So there are instances where those four don't map to the same thing? > Not in a typical situation, it can happen if the chip was removed and another one took its place which is very unlikely. I just think that we cannot have any "hard data" as in: a programmatic reference to the chip in the request (their lifetimes are not connected), so the next best thing is the filesystem path. Bart