Messages in this thread | | | Date | Fri, 13 Nov 2015 03:26:01 +0200 | Subject | Re: [PATCH v3 2/5] tty: Introduce SER_RS485_SOFTWARE read-only flag for struct serial_rs485 | From | Andy Shevchenko <> |
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On Fri, Nov 13, 2015 at 3:11 AM, Peter Hurley <peter@hurleysoftware.com> wrote: > On 11/12/2015 07:41 PM, Andy Shevchenko wrote: >> On Thu, Nov 12, 2015 at 10:22 PM, Peter Hurley <peter@hurleysoftware.com> wrote: >>> On 11/12/2015 02:57 PM, One Thousand Gnomes wrote: >> >>> An illustrative (kernel-space) example is the mess that is dmaengine_pause(). >>> Some DMA implementations provide the means to stop and restart DMA without >>> losing data and some DMA implementations do not. Unfortunately, some >>> advertise they support dmaengine_pause() but only for lossy uses like audio. >>> Because the api hides this, the query interface for pause support is >>> useless. >> >> The DMA pause() call means only pause with possibility to resume. >> There is a resume() call as well. Any driver which treats pause() as a >> complete stop is buggy driver and should be fixed. > > How about pause _without_ the possibility to resume? > > https://groups.google.com/d/msg/linux.kernel/Abe0hfGcgsw/H0se55wC558J
Briefly what I got from the thread that Russel shows similar view on the API, so that's why he was objecting to add pause/resume calls for a specific hardware.
-- With Best Regards, Andy Shevchenko
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