On Thu, Jun 15, 2023 at 06:19:37PM +0200, Arnaud POULIQUEN wrote: > > > On 6/15/23 16:50, Bjorn Andersson wrote: > > On Thu, Jun 15, 2023 at 11:01:14AM +0200, Arnaud POULIQUEN wrote: > >> > >> > >> On 6/14/23 17:54, Bjorn Andersson wrote: > >>> On Sat, Apr 22, 2023 at 04:12:05PM +0530, Sarannya S wrote: > >>>> From: Deepak Kumar Singh <quic_deesin@xxxxxxxxxxx> > >>>> > >>>> Some transports like Glink support the state notifications between > >>>> clients using flow control signals similar to serial protocol signals. > >>>> Local glink client drivers can send and receive flow control status > >>>> to glink clients running on remote processors. > >>>> > >>>> Add APIs to support sending and receiving of flow control status by > >>>> rpmsg clients. > >>>> > >>>> Signed-off-by: Deepak Kumar Singh <quic_deesin@xxxxxxxxxxx> > >>>> Signed-off-by: Sarannya S <quic_sarannya@xxxxxxxxxxx> > >>>> --- > >>>> drivers/rpmsg/rpmsg_core.c | 21 +++++++++++++++++++++ > >>>> drivers/rpmsg/rpmsg_internal.h | 2 ++ > >>>> include/linux/rpmsg.h | 15 +++++++++++++++ > >>>> 3 files changed, 38 insertions(+) > >>>> > >>>> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c > >>>> index a2207c0..e8bbe05 100644 > >>>> --- a/drivers/rpmsg/rpmsg_core.c > >>>> +++ b/drivers/rpmsg/rpmsg_core.c > >>>> @@ -331,6 +331,25 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, > >>>> EXPORT_SYMBOL(rpmsg_trysend_offchannel); > >>>> > >>>> /** > >>>> + * rpmsg_set_flow_control() - sets/clears serial flow control signals > >>>> + * @ept: the rpmsg endpoint > >>>> + * @enable: pause/resume incoming data flow > >>> > >>> As shown in the discussion, it's still not clear what true/false means. > >>> Also, let's try to clarify that it's a request for the other side to do > >>> something: > >>> > >>> * rpmsg_set_flow_control() - request remote to pause/resume transmission > >>> * ... > >>> * @enable: flow restricted > >>> * ... > >>> > >>> > >>> PS. There's a stray space at the end of the line. > >> > >> The notion of flow restricted seems to me also ambiguous. It does > >> not specify if the stream is limited in term of bandwidth or stopped. > >> > >> What about using XON/XOFF as specified in software flow control[1] > >> > >> XOFF Pause transmission > >> XON Resume transmission > >> > >> or simply pause/resume definitions > >> > > > > I agree, that's still ambiguous. > > > > I was concerned about expressing it such that the reader would assume > > that calling this means there will be no more data coming, but there > > might be things in the queues etc. Expressing it in terms of the state > > of transmission is clearer. > > > > > > /* > > * rpmsg_set_flow_control() - request remote to pause/resume transmission > > ... > > * @enable: Pause transmission > > ... > > */ > > > > Does that sound okay and clear to you? > > Much better! I still have a nitpicking point :) > What about replacing @enable variable by @pause to align the variable with the > usage? > /* > * rpmsg_set_flow_control() - request remote to pause/resume transmission > ... > * @pause: set to 1 to pause transmission, to 0 to resume the transmission It's a boolean, so I think with your name change suggestion, together with the function description, it should be clear enough what the two states (true/false) means. * @pause: Pause transmission Thanks, Bjorn