i.MX Processorsのトピック/dev/spidev not appearing on iMX6Q despite kernel configuration and modalias="spidev"

/dev/spidev not appearing on iMX6Q despite kernel configuration and modalias="spidev"

muthuswamydiksh — Tue, 08 Apr 2014 16:21:11 GMT

I am using iMX6Q with BSP L3.0.35_4.1.0.

I configured the kernel in imx6_defconfig.dev as

CONFIG_SPI_SPI_DEV=y

CONFIG_SPI=y

CONFIG_SPI_MASTER=y

I modified the /arch/arm/mach-mx6/board-*.c file.

I did the following changes.

IOMUX for chip select.

static int mx6q_spi_cs[] = {

-1, IS THIS A PROMLEM? I want to use SS of ecspi.

};

static const struct spi_imx_master e25_mx6q_spi_data __initconst = {

.chipselect = e25_mx6q_spi_cs,

.num_chipselect = ARRAY_SIZE(e25_mx6q_spi_cs),

};

static struct spi_board_info my_spi5_board_info[] __initdata = {

{

/* The modalias must be the same as spi device driver name */

.modalias = "spidev",

.max_speed_hz = 10000000,

.bus_num = 4,

.chip_select = 0,

.platform_data = NULL,I

};

imx6q_add_ecspi(4, &mx6q_spi_data);

spi_device_init();

I tried to configure CS a GPIO nd gave teh corresponding GPIO number in the mc6q_spi_cs struct. But not luck.

Any pointers would be very helpful.

Re: /dev/spidev not appearing on iMX6Q despite kernel configuration and modalias="spidev"

muthuswamydiksh — Tue, 08 Apr 2014 16:23:10 GMT

I referred:

spidev

how open spidev on imx28 platform?

But still it is not appearing.

Re: /dev/spidev not appearing on iMX6Q despite kernel configuration and modalias="spidev"

Wlodek_D_ — Wed, 09 Apr 2014 09:17:26 GMT

Hello,

Thank you for your post, however please consider moving it to the right community place (e.g. i.MX Community ) to get it visible for active members.

For details please see general advice Where to post a Discussion?

Thank you for using Freescale Community.

Re: /dev/spidev not appearing on iMX6Q despite kernel configuration and modalias="spidev"

muthuswamydiksh — Sat, 26 Apr 2014 10:26:00 GMT

Move the post to i.MX Commnity.

I found the solution.

The port pin has to be correctly configured for the required chip select in IOMUX.

The array has to be:

static int mx6q_spi_cs[] = {

-1,

};

three -1s are required here as i am using CS2. If you dig more into kernel spi code, you will find that size of the array mx6q_spi_cs has to be greater than your .chip_select field. With these changes, I can see /dev/spi4.2.

Hope this helps.