Re: [PATCH 2/8] spi: spi-s3s64xx: Add S3C64XX_SPI_QUIRK_CS_AUTO for Exynos3250
From: Mark Brown <broonie@kernel.org>
Date: 2020-08-19 19:38:51
Also in:
linux-samsung-soc, linux-spi, lkml
From: Mark Brown <broonie@kernel.org>
Date: 2020-08-19 19:38:51
Also in:
linux-samsung-soc, linux-spi, lkml
On Wed, Aug 19, 2020 at 03:01:21PM +0200, Lukasz Stelmach wrote:
It was <2020-08-19 śro 14:39>, when Krzysztof Kozlowski wrote:
quoted
There is here no commit msg, no explanation.
As I wrote in the cover letter, this and previous commits make things work on Exynos3250 (ARTIK5 precisely). I can't explain why. I read everything I could about this HW and there were no details about automatic CS handling other than how to turn it on and off.
What is similar about those other SoCs - could you be more specific here, or what goes wrong if you don't set this? The auto mode (or at least the auto mode that was on the Exynos7) is not compatible with many SPI devices if the controller chip select is actually in use, the quirk was added for controllers that just don't have the manual mode. See also: https://lore.kernel.org/linux-spi/CAAgF-BfGwcNzMx0meFVkJqNMTbQ4_PP1PZ3i6edOm6U3bc26_Q@mail.gmail.com/ (local) for an explanation of the quirk.