I have a hikey LeMaker 620 on which I am trying to enable I2C support as currently I am not getting /dev/i2c* node.
I am using the docs here : https://github.com/96boards/documentation/blob/master/consumer/hikey/hikey620/build/linux-kernel.md
I see that
I2C_DESIGNWARE_PLATFORM
I2C_CHARDEV
are already enabled, still I do not see anything in /sys/bus/i2c/devices/ and as a result my i2cdetect fails saying “/dev/i2c/0 : No such file or directory”
Can someone please help.
Is there any problem with dts file?
/ # dmesg | grep i2c
[ 0.251154] i2c-core: driver [dummy] registered
[ 0.284233] i2c-core: driver [pca953x] registered
[ 0.286078] i2c-core: driver [sec_pmic] registered
[ 0.287137] i2c_designware f7100000.i2c: could not find pctldev for node /soc/pinmux@f7010000/i2c0_pmx_func, deferring probe
[ 0.287167] i2c_designware f7101000.i2c: could not find pctldev for node /soc/pinmux@f7010000/i2c1_pmx_func, deferring probe
[ 0.287188] i2c_designware f7102000.i2c: could not find pctldev for node /soc/pinmux@f7010000/i2c2_pmx_func, deferring probe
[ 0.323590] i2c-core: driver [cs2000-cp] registered
[ 0.328647] i2c-core: driver [fan53555-regulator] registered
[ 0.340913] i2c-core: driver [cros-ec-i2c] registered
[ 0.341005] i2c-core: driver [max77620] registered
[ 0.341054] i2c-core: driver [rk808] registered
[ 0.351637] i2c-core: driver [usb3503] registered
[ 0.353610] i2c-core: driver [rtc-ds3232] registered
[ 0.354842] i2c /dev entries driver
[ 0.355782] i2c-core: driver [pca954x] registered
[ 0.356294] i2c-core: driver [bq27xxx-battery] registered
[ 0.501408] i2c-core: driver [hmc5843] registered
[ 2.209817] i2c_designware f7100000.i2c: Unknown Synopsys component type: 0x00000000
[ 2.218809] i2c_designware f7101000.i2c: Unknown Synopsys component type: 0x00000000
[ 2.227621] i2c_designware f7102000.i2c: Unknown Synopsys component type: 0x00000000I am surprised that no one has answer to this.
I see a lot of questions here been asked for other i2c problems once they have those nodes. So at least I request those folks to share their kernel configs with with they were getting the /dev/i2c* nodes.
You don’t see I2C controllers because of init error:
[ 2.209817] i2c_designware f7100000.i2c: Unknown Synopsys component type: 0x00000000
[ 2.218809] i2c_designware f7101000.i2c: Unknown Synopsys component type: 0x00000000
[ 2.227621] i2c_designware f7102000.i2c: Unknown Synopsys component type: 0x00000000
Look like something prevent the driver to correctly read a register:
https://elixir.bootlin.com/linux/v4.15.18/source/drivers/i2c/busses/i2c-designware-master.c#L65
Not sure why, did you change the device tree in any way?
No I did not change anything. I just take the exact kernel and used the same steps to build the kernel defined at : https://github.com/96boards/documentation/blob/master/consumer/hikey/hikey620/build/linux-kernel.md
$ git clone https://github.com/suihkulokki/linux.git
$ git checkout -t origin/hikey-v4.15
$ export ARCH=arm64
$ export CROSS_COMPILE=<path-to-cross-compiler>/aarch64-linux-gnu-gcc-
$ make defconfig distro.config
$ make menuconfig #add I enabled some I2C flags
$ make -j111
I did not change anything after cloning that kernel, except few kernel configs relating to I2C.
@Naveen_Chaudhary Just for the confirmation, did you flash latest firmware as well? BoardRecovery for hikey - 96Boards
I have not flashed those pre-built binaries but have prepared my own firmware and u-boot as mentioned here : https://github.com/qemu/u-boot/tree/master/board/hisilicon/hikey
What exactly are those? You don’t need to enable any additional Kconfig options for getting I2C to work.
Ok. When I tried very first time with that released configs (by adding no personal changes) i did not see any i2c nodes. After that only I started trying with enabling additional configs with a hope to see some i2c nodes.
So, with the original config also, it did not work for me. No /dev/i2c* or nothing in /sys/bus/i2c/devices/ and /sys/class/i2c-dev/ .
That’s weird. Btw, can you please try the same build instructions with this kernel tree? manivannan.sadhasivam/hikey.git - [no description]
Please make sure that the tree is clean before building.
Sure. Can you please tell the kernel config to use. I mean the kernel config command to run before make.
Same as before:
$ make defconfig distro.config
I have started the cloning and will update the results in next 1-2 hours.
Hi,
I see the exact same behaviour with 4.19.5 that you shared.
/ # uname -a
Linux 10.0.0.225 4.19.5 #1 SMP PREEMPT Thu Mar 7 09:41:28 IST 2019 aarch64 GNU/Linux
/ # ls /sys/i2c*
ls: /sys/i2c*: No such file or directory
/ # ls /sys/bus/i2c/devices/
/ #
/ #
/ # ls /sys/class/i2c-dev/
/ #
/ #
Here’s the dmesg with this new kernel :
/ # dmesg | grep i2c
[ 0.396588] i2c /dev entries driver
[ 0.796432] i2c_designware f7100000.i2c: Unknown Synopsys component type: 0x00000000
[ 1.408924] i2c_designware f7101000.i2c: Unknown Synopsys component type: 0x00000000
[ 2.156303] i2c_designware f7102000.i2c: Unknown Synopsys component type: 0x00000000
Here is my boot.scr (just for reference) :
tftpboot 0x80000 10.0.0.1:uImage
tftpboot 0x2000000 10.0.0.1:hi6220-hikey.dtb
setenv bootargs 'console=ttyAMA3,115200n8 root=/dev/nfs nfsroot=10.0.0.1:/home/naveen/rootfs-arm64,nolock,vers=4,tcp ip=dhcp rw'
bootm 0x80000 - 0x2000000Okay. I’ll try to reproduce this behaviour with my hikey running u-boot and get back to you.
Thanks,
Mani
Were you able to reproduce this issue?
@Naveen_Chaudhary Yes, I can reproduce the issue on my hikey. It seems like u-boot is missing some configs for enabling I2C properly. I2C is working fine with our official UEFI build.
I have created a bug report for tracking this issue: https://bugs.96boards.org/show_bug.cgi?id=822
Thanks for reporting. We will work on resolving this issue asap.
-Mani
Please try the below commit for resolving this issue:
I have submitted a patch [1] to u-boot ML for the same.
Thanks,
Mani
[1] [U-Boot] [PATCH] hikey: Take peripherals out of reset during board init
Thanks Mani,
I tried this patch and it worked just fine. I can see the /dev/i2c-* nodes now.
Thanks for your great support.
I also connected a sensor to I2C-1 and able to get the sensor on bus.
/ # i2cdetect -r 1
i2cdetect: WARNING! This program can confuse your I2C bus
Continue? [y/N] y
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- 13 -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
0x13 is my sensor address. I was also able to communicate with the sensor well. However, for some reason, I was not able to get the sensor working on I2C-0 as the device didn’t show up. However, this could be because of muxing, which I can see. Thanks Mani for the patch, it really unblocked me 
