Hi all,
I currently work with the MCIMMX6Q-SDB board from Freescale. The kernel is taken from Yocto/Dylan core-image-base as it is, without change in config.
I tried to write a small userspace-application which uses the accelerator MMA8451 via I2C.
I figured out how the MMA is connected to the CPU and tried to do the following:
| dev = open ("/dev/i2c-0", O_RDWR); |
if (dev < 0) {
| | err = errno; |
| | perror("==> ERROR open:"); | | | |
| | printf("errno = %d\n", err); |
| | close(dev); |
| | exit (1); |
}
if (ioctl(dev, I2C_SLAVE, I2C_DEV_ADR_MMA8451) < 0) {
| | err = errno; |
| | perror("==> Error ioctl:"); | |
| | printf("errno = %d\n", err); |
| | close(dev); | |
| | exit (1); |
}
The syscall ioclt comes up with the following error;
==> Error ioctl:: Device or resource busy
errno = 16
If I use
| if (ioctl(dev, I2C_SLAVE_FORCE, I2C_DEV_ADR_MMA8451) < 0) { |
instead, the I2C basicly works.
After some search, I found the following:
root@imx6qsabresd:/sys/devices/virtual/input/input3# cat name
mma845x
So this makes me thinking, that there is a virtual device driver in the system which uses the i2c-driver as well.
But I cant find any informations about this.
Does anyone have experience on that ?
Best regards
Karsten
