Messages in this thread | | | Date | Fri, 22 May 2015 13:25:44 +0100 | From | Mark Brown <> | Subject | Re: [PATCH] spi: omap2-mcspi: Fix native cs with new set_cs |
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On Thu, May 21, 2015 at 06:48:33PM -0500, Michael Welling wrote:
> So after reverting this patch I found there is a issue in that it is difficult > to determine when a transfer is complete to properly drive the chipselect from > within the transfer_one function.
Is unprepare_message() a suitable place here? I've got a feeling the answer is no...
> Then I figured that we could handle the case when GPIOs are being used with > some conditional calls to omap2_mcspi_set_cs in the omap2_mcspi_work_one > function. > > Near the beginning of the function I added: > if (gpio_is_valid(spi->cs_gpio)) > omap2_mcspi_set_cs(spi, 0); > > Near the end of the function I added: > if (gpio_is_valid(spi->cs_gpio)) > omap2_mcspi_set_cs(spi, 1); > > This makes GPIO chip select support work while leaving the native working > as previous. > > Is this solution acceptible?
I think that's probably OK as well, it's not ideal though (and risky if the chip select is routed somewhere...).
> In the process of reviewing the changes I found a few other things that > should be changed as well.
Please send fixes for these as separate patches (ideally without any dependency on your new work so we can send them to Linus as fixes).
> Here you will see a delay that is already handled by the core spi driver: > https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/drivers/spi/spi-omap2-mcspi.c#n1166
I can't actually see that since I have no internet access right now! [unhandled content-type:application/pgp-signature] | |