On 23/04/16 01:18, cjvijf@gmail.com wrote:

Hello,

I am running Centos on a raspberry pi 2b. (I downloaded the image from: http://people.centos.org/hughesjr/armv7hl/rpi2/images/ rpi2-centos-image.img.xz ) and installed the i2c libraries and modules for i2c. [root@rpi2-2 ~]# lsmod | grep i2c

i2c_bcm2708 5006 0 i2c_dev 6027 0

From what I read that should be correct

device file is there too: crw------- 1 root root 89, 1 Dec 31 1969 i2c-1

kernel: Linux rpi2-2 3.18.14-v7+ #794 SMP PREEMPT Sun Jun 7 12:50:51 BST 2015 armv7l armv7l armv7l GNU/Linux

However, when I scan the i2c bus with 'i2cdetect -y 1' I don't see any devices (and I tried 2 that I know work).

is the I2C stuff in this kernel working? (or is there a newer kernel version?)

thanks,

Ron

P.S. I know this is an arm-dev list, but figured the I2C topic would fit better here than in a general Centos list

I know it's a very old post, but I had to search for a friend of mine, using CentOS 7.3.1611 on his rpi2 , so here we go :

We need to activate it through config.txt :

echo -e "dtparam=i2c1=on\ndtparam=i2c_arm=on" >> /boot/config.txt echo -e "i2c-bcm2708\ni2c-dev" >> /etc/modules-load.d/i2c.conf yum install -y i2c-tools systemctl reboot

Once rebooted :

[root@rpi2 ~]# i2cdetect -y 1 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: -- -- -- -- -- -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- --