Messages in this thread | | | Subject | Re: SPI not working on 5.10 and 5.11, bisected to 766c6b63aa04 ("spi: fix client driver breakages when using GPIO descriptors") | From | Christophe Leroy <> | Date | Thu, 14 Jan 2021 12:27:42 +0100 |
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Le 13/01/2021 à 13:33, Mark Brown a écrit : > On Wed, Jan 13, 2021 at 09:49:12AM +0100, Christophe Leroy wrote: > >> With commit 766c6b63aa04 ("spi: fix client driver breakages when using GPIO >> descriptors") reverted, it is back to work: > > ... > >> What shall I do ? > > I would guess that there's an error with the chip select polarity > configuration on your system that just happened to work previously, I'd > suggest fixing this in the board configuration to bring it in line with > everything else. >
Not that easy.
Today I have in the DTS the CS GPIOs declared as ACTIVE_LOW.
If I declare them as ACTIVE_HIGH instead, then I also have to set spi-cs-high property, otherwise of_gpio_flags_quirks() is not happy and forces the GPIO ACTIVE LOW.
When I set spi-cs-high property, it sets the SPI_CS_HIGH bit in spi->mode.
In fsl_spi_chipselect(), we have
bool pol = spi->mode & SPI_CS_HIGH
Then pdata->cs_control(spi, pol);
So changing the board config is compensated by the above, and at the end it still doesn't work.
Whereas reverting the above mentionned commit sets back SPI_CS_HIGH into spi->mode without changing the ACTIVE level of the GPIO, resulting in the correct polarity.
So, I'm a bit lost, where is the problem exactly ?
Thanks Christophe
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