Messages in this thread | | | Date | Fri, 22 May 2020 15:34:27 +0300 | From | Andy Shevchenko <> | Subject | Re: [PATCH v4 01/16] spi: dw: Add Tx/Rx finish wait methods to the MID DMA |
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On Fri, May 22, 2020 at 01:18:20PM +0100, Mark Brown wrote: > On Fri, May 22, 2020 at 03:12:21PM +0300, Andy Shevchenko wrote: > > On Fri, May 22, 2020 at 02:52:35PM +0300, Serge Semin wrote: > > > > Please, see it's implementation. It does atomic delay when the delay value > > > is less than 10us. But selectively gets to the usleep_range() if value is > > > greater than that. > > > Oh, than it means we may do a very long busy loop here which is not good at > > all. If we have 10Hz clock, it might take seconds of doing nothing! > > Realistically it seems unlikely that the clock will be even as slow as > double digit kHz though, and if we do I'd not be surprised to see other > problems kicking in. It's definitely good to handle such things if we > can but so long as everything is OK for realistic use cases I'm not sure > it should be a blocker.
Perhaps some kind of warning? Funny that using spi_delay_exec() will issue such a warning as a side effect of its implementation.
-- With Best Regards, Andy Shevchenko
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