Re: Boot failure with 5.4-rc5, bisected to 0f0581b24bd0 ("spi: fsl: Convert to use CS GPIO descriptors")

[Linus Walleij <linus.walleij@linaro.org>]

On Wed, Nov 27, 2019 at 1:05 PM Christophe Leroy
<christophe.leroy@c-s.fr> wrote:
> Le 27/11/2019 à 11:55, Linus Walleij a écrit :

> > That's weird, because when ->use_gpio_descriptors is set
> > (as for this driver) the core only attempts to look up
> > spi->cs_gpiods and not spi->cs_gpios, and consequently
> > can only assign spi->cd_gpiod and not spi->cs_gpio:
>
> That's it. ->use_gpio_descriptors isn't set for the FSL driver:

Oh, my coding mistake. :(

And an especially stupid one too. OK I make a separate patch
in the series to fix that too.

> I have now added it, together with the DTS cs-gpios name change (without
> your counting patch with crashes), and I get something which is almost
> working: I get temperature back into sensors, but temperature is 0°C !!!

OK we almost fixed it I think. It is probably better to test with
all three patches (will send out soon) that rely on the gpiolib
to do appropriate counting of the gpiod's and so on.

> Looking into dmesg, I see:
>
> [    3.153521] lm74@1 GPIO handle specifies active low - ignored
> [    3.178093] lm74@5 GPIO handle specifies active low - ignored
>
> Any link with the problem ?

This is because your GPIO handles look like this:

        gpios = <&CPM1_PIO_C 4 1        /* SICOFI 1 */
                 &CPM1_PIO_B 23 1       /* TEMP MCR */
                 &CPM1_PIO_C 8 1        /* SICOFI 2 */
                 &CPM1_PIO_C 12 1       /* EEPROM MIAE */
                 &CPM1_PIO_D 6 1        /* SICOFI 3 */
                 &CPM1_PIO_B 14 1       /* TEMP MPC885 */
                 &CPM1_PIO_B 21 1       /* EEPROM CMPC885 */
                 &FAV_CS_SPI 0 1        /* FAV SPI */
                 &FAV_CS_SPI 2 1>;      /* FAV POSTE FPGA */

That "1" at the end of each GPIO phandle means "active low"
as can be seen in <dt-bindings/gpio/gpio.h>

/* Bit 0 express polarity */
#define GPIO_ACTIVE_HIGH 0
#define GPIO_ACTIVE_LOW 1

But your child nodes look like this:

       sicofi@0 {
                compatible = "infineon,sicofi";
                spi-max-frequency = <1000000>;
                reg = <0>;
                spi-cs-high;
                spi-cpha;
        };

        lm74@1 {
                compatible = "ns,lm74";
                spi-max-frequency = <1000000>;
                reg = <1>;
                spi-cs-high;
        };

And the spi-cs-high in the child node takes precedence.

That's a bit ambigous so that is what the warning is about.

Try to remove the "spi-cs-high" bool flag from your nodes,
because it seems like the old code was ignoring them.

Does that solve the problem?

Yours,
Linus Walleij