Re: [PATCH] usbserial: pl2303 tx xon/xoff flow control

2018-05-21 Thread Johan Hovold
On Sun, May 20, 2018 at 02:22:27AM +0200, Florian Zumbiehl wrote: > Before I investigated how to implement this patch I just saw that s/w flow > control "didn't work", but my assumption was that that was due to buffering > latencies, not because the kernel just ignored the request. But then, > cha

Re: [PATCH] usbserial: pl2303 tx xon/xoff flow control

2018-05-19 Thread Florian Zumbiehl
Hi, > > That at least matches the labeling on the chip, so I guess that might be > > correct? > > Then it's an HX (even if the driver algorithm for detecting the type may > be wrong). Well, I do own at least one USB RS232 adapter that I very much suspect being a fake pl2303--though the chip is b

Re: [PATCH] usbserial: pl2303 tx xon/xoff flow control

2018-05-18 Thread Johan Hovold
On Fri, May 18, 2018 at 06:06:53AM +0200, Florian Zumbiehl wrote: > Hi, > > > > There are historical reasons for a lot of things, but that's not > > > necessarily a reason to continue taking shortcuts. > > > > But on second thought, I think your approach here makes sense. If > > usbserial ever ga

Re: [PATCH] usbserial: pl2303 tx xon/xoff flow control

2018-05-18 Thread Johan Hovold
On Fri, May 18, 2018 at 06:06:09AM +0200, Florian Zumbiehl wrote: > Hi, > > > That looks like an HX device according to the current way we identify > > these types (which may be wrong). > > That at least matches the labeling on the chip, so I guess that might be > correct? Then it's an HX (even

Re: [PATCH] usbserial: pl2303 tx xon/xoff flow control

2018-05-17 Thread Florian Zumbiehl
Hi, > > There are historical reasons for a lot of things, but that's not > > necessarily a reason to continue taking shortcuts. > > But on second thought, I think your approach here makes sense. If > usbserial ever gains generic IXON support, we'd just fall back to the > line-discipline implement

Re: [PATCH] usbserial: pl2303 tx xon/xoff flow control

2018-05-17 Thread Florian Zumbiehl
Hi, > That looks like an HX device according to the current way we identify > these types (which may be wrong). That at least matches the labeling on the chip, so I guess that might be correct? > Continuation lines (e.g. the broken if statement) should be indented > substantially to the right, w

Re: [PATCH] usbserial: pl2303 tx xon/xoff flow control

2018-05-17 Thread Johan Hovold
On Thu, May 17, 2018 at 10:29:14AM +0200, Johan Hovold wrote: > On Thu, May 17, 2018 at 05:39:21AM +0200, Florian Zumbiehl wrote: > > Now, I agree that signaling lack of support would be better in general, but > > it does change what the code does for (still) unsupported cases. After all, > > usbs

Re: [PATCH] usbserial: pl2303 tx xon/xoff flow control

2018-05-17 Thread Johan Hovold
On Thu, May 17, 2018 at 05:39:21AM +0200, Florian Zumbiehl wrote: > Hi, > > > > Note that the patch has only been fully tested with kernel 4.9.28, and > > > test-compiled against 4.16.8. Tested only with the pl2303 adapters I have > > > available (which seem to be type 0 if I interpret the code co

Re: [PATCH] usbserial: pl2303 tx xon/xoff flow control

2018-05-16 Thread Florian Zumbiehl
Hi, > > Note that the patch has only been fully tested with kernel 4.9.28, and > > test-compiled against 4.16.8. Tested only with the pl2303 adapters I have > > available (which seem to be type 0 if I interpret the code correctly), I > > don't have a clue whether this works with other versions of

Re: [PATCH] usbserial: pl2303 tx xon/xoff flow control

2018-05-16 Thread Johan Hovold
On Mon, May 14, 2018 at 05:15:11AM +0200, Florian Zumbiehl wrote: > Support hardware-level Xon/Xoff flow control in transmit direction with > pl2303. > > Signed-off-by: Florian Zumbiehl > --- > Note that the patch has only been fully tested with kernel 4.9.28, and > test-compiled against 4.16.8.