topic Re: spi device name in i.MX Processors

spi device name

niklasmolin — Sat, 01 Mar 2014 02:51:39 GMT

Hi.

I'm trying to use 2 ecspi buses.

The problem is that only device name for one bus shows up.

So I think it uses the same name.

If I for instance have:

&ecspi1 {

fsl,spi-num-chipselects = <2>;

cs-gpios = <&gpio4 9 0>, <&gpio5 9 0>;

pinctrl-names = "default";

pinctrl-0 = <&pinctrl_ecspi1_2>;

status = "okay";

chip1: spidev@0 {

compatible = "spidev";

spi-max-frequency = <20000000>;

reg = <0>;

};

chip2: spidev@1 {

compatible = "spidev";

spi-max-frequency = <20000000>;

reg = <1>;

};

&ecspi3 {

fsl,spi-num-chipselects = <1>;

cs-gpios = <&gpio4 24 0>;

pinctrl-names = "default";

pinctrl-0 = <&pinctrl_ecspi3_1>;

status = "okay";

chip3: spidev@0 {

compatible = "spidev";

spi-max-frequency = <20000000>;

reg = <0>;

};

I will only see spidev32766.0 and spidev32766.1 in the /dev directory

Shouldn't the SPI bus number also be included in the device name?

How do I change the name the device will have in /dev?

Thanks,

Niklas

Re: spi device name

alejandrolozan1 — Mon, 10 Mar 2014 15:10:39 GMT

Hi,

Have you change the spi_board_info spi_device_info struct?

I believe this is the one that has the bus number:

struct spi_board_info {

char modalias[SPI_NAME_SIZE];

const void * platform_data;

void * controller_data;

int irq;

u32 max_speed_hz;

u16 bus_num;

u16 chip_select;

u16 mode;

};

Maybe this other discussion helps.

spidev

I hope this helps,

Alejandro

Re: spi device name

niklasmolin — Tue, 11 Mar 2014 18:38:01 GMT

It seems like they are using a different name scheme now.

My question is, how do I easily check how the spi driver name translates to the specific bus number.

I can't just hard code the spi-driver name in my code, since it might change when I start the kernel.

It seems to be some information in /sys/bus/spi....., but how do I get that information from my code?

Thanks,

Niklas