iMX28 enable SPI in Linux 3.10

[silviagonzalez]

Hello

We’re trying to enable the SPI functionality in an iMX287 with kernel 3.10.

We’ve added the highlighted lines to the imx28-mba28.dts file:

apb@80000000 {

                               apbh@80000000 {

                                               pinctrl@80018000 {

                                               ...           

                                               };

                               };

                               apbx@80040000 {

                                              ssp2: ssp@80014000 {

                                                               #address-cells = <1>;

                                                               #size-cells = <0>;

                                                               compatible = "fsl,imx28-spi";

                                                               pinctrl-names = "default";

                                                               pinctrl-0 = <&spi2_pins_a>;

                                                               status = "okay";

                                                               flash: m25p80@0 {

                                                                              #address-cells = <1>;

                                                                              #size-cells = <1>;

                                                                              compatible = "m25p80,fsl,imx28-spi";

                                                                              spi-max-frequency = <40000000>;

                                                                              reg = <0>;

                                                               };

                                               };

                               };

                };

But we’ve found that unless we comment the following highlighted lines in the imx28.dtsi file the compilation fails:

apb@80000000 {

                               apbh@80000000 {

                                               compatible = "simple-bus";

                                               #address-cells = <1>;

                                               #size-cells = <1>;

                                               reg = <0x80000000 0x3c900>;

                                               ranges;

                                               /*ssp2: ssp@80014000 {

                                                               #address-cells = <1>;

                                                               #size-cells = <0>;

                                                               reg = <0x80014000 0x2000>;

                                                               interrupts = <98 84>;

                                                               clocks = <&clks 48>;

                                                               dmas = <&dma_apbh 2>;

                                                               dma-names = "rx-tx";

                                                               fsl,ssp-dma-channel = <2>;

                                                               status = "disabled";

                                               };*/

                                               pinctrl@80018000 {

                                                               #address-cells = <1>;

                                                               #size-cells = <0>;

                                                               compatible = "fsl,imx28-pinctrl", "simple-bus";

                                                               reg = <0x80018000 0x2000>;

                                                               spi2_pins_a: spi2@0 {

                                                                              reg = <0>;

                                                                              fsl,pinmux-ids = <

                                                                                              0x2100 /* MX28_PAD_SSP2_SCK__SSP2_SCK */

                                                                                              0x2110 /* MX28_PAD_SSP2_MOSI__SSP2_CMD */

                                                                                              0x2120 /* MX28_PAD_SSP2_MISO__SSP2_D0 */

                                                                                              0x2130 /* MX28_PAD_SSP2_SS0__SSP2_D3 */

                                                                              >;

                                                                              fsl,drive-strength = <1>;

                                                                              fsl,voltage = <1>;

                                                                              fsl,pull-up = <1>;

                                                               };

                                               };

                               apbx@80040000 {

                                               compatible = "simple-bus";

                                               #address-cells = <1>;

                                               #size-cells = <1>;

                                               reg = <0x80040000 0x40000>;

                                               ranges;

                               };

                };

};

Once we comment these lines the compilation is successfully completed but when booting the system we get the following error:

mxs-spi: probe of ssp.5 failed with error -22

Are we missing anything? Could you help us, please?

Thanks in advance for your help.

[alejandrolozan1 · Accepted solution]

Hi,

You can also check the binding documentation.
https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/tree/Documentation/devicetree/b...

Alejandro

[fabio_estevam]

Hi Silvia,

The compatible string you use is not correct.

Take a look at this dts file that shows the usage of a m25p80 spi flash on mx28:

https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/tree/arch/arm/boot/dts/imx28-m2...