UP Board 4.4 Linux Kernel for Ubuntu 16.04 and 14.04 is now available

DCleriDCleri Administrator, AAEON Posts: 644 admin
New Ubuntu 14.04 and Ubuntu 16.04 4.4 Kernel packages for the UP...

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Comments

  • KurtKurt New Member Posts: 146 ✭✭
    Thanks,

    So I installed on 16.04 following the instructions. Was wondering if there is something else I need to do to access the GPIO pins from Ubuntu.
    [email protected]:~$ uname -a
    Linux kurt-UP-CHT01 4.4.0-1-upboard #10-Ubuntu SMP Fri Sep 23 12:26:42 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
    [email protected]:~$ echo 26 > /sys/class/gpio/export
    -bash: /sys/class/gpio/export: Permission denied
    [email protected]:~$ sudo echo 26 > /sys/class/gpio/export
    -bash: /sys/class/gpio/export: Permission denied
    [email protected]:~$ ls /sys/class/gpio
    export  gpiochip0  gpiochip318  gpiochip373  gpiochip397  gpiochip456  unexp
    

    Thanks
  • Dan O'DonovanDan O'Donovan Emutex Posts: 227 mod
    Hi Kurt

    You can access the 28 GPIO pins on the 40-pin HAT I/O header via gpiochip0.
    You'll find the corresponding Linux GPIO numbers for each of the pins in a column in the table on this page:
    https://up-community.org/wiki/Pinout

    If you want to use a Python library to access the GPIO/I2C/SPI/UART/PWM functions on those pins, I recommend libMRAA. There are instructions for installing it for Ubuntu on this page: https://github.com/intel-iot-devkit/mraa
    And some examples for using it on UP here: https://up-community.org/wiki/MRAA/UPM

    Enjoy! :-)
  • KurtKurt New Member Posts: 146 ✭✭
    edited September 2016
    Thanks Dan,

    Note: from the wiki pinout page, I was following the first example:
    echo 26 > /sys/class/gpio/export
    echo out > /sys/class/gpio/gpio26/direction
    echo 1 > /sys/class/gpio/gpio26/value
    
    Which fails as Permission Denied on the first echo which should have made the pin available. So I think something is wrong.

    I am a C/C++ type guy but will try MRAA again. I used it when I was playing with the Edison and I have downloaded my fork which I synced up to the main one of it and have now built it. Will take a look to see maybe it is maybe using memory mapped access instead of file system access?

    Maybe I need to see if I can plug in one of my Edisons and see if there is differences, like maybe the owner of the file system. As far as I can tell with UP it looked like root, but sudo did not help.

    Edit: pulled out Edison, took awhile to remember that on here was logged in as Root also does not have access control, so things might be different

    Will keep trying.

    Thanks
  • KurtKurt New Member Posts: 146 ✭✭
    edited September 2016
    As I mentioned I built my version of MRAA which is in sync with https://github.com/intel-iot-devkit/mraa

    I tried running the example: blink-io

    And it failed, at least on the default pin 8 as well as pin 26.
    Are you sure that pin8 you requested is valid on your [email protected]:~/mraa/build/examples$ ./blink-io 26
    MRAA Version: v0.5.1-941-g92fdb8a
    Starting Blinking on IO26
    Are you sure that pin26 you requested is valid on your [email protected]:~/mraa/build/examples$ cd ../..
    

    Looking at the source of example:
    mraa_gpio_context gpio;
        gpio = mraa_gpio_init(iopin);
        if (gpio == NULL) {
            fprintf(stderr, "Are you sure that pin%d you requested is valid on your platform?", iopin);
            exit(1);
        }
        printf("Initialised pin%d\n", iopin);
    
    So mraa_gpio_init is failing, my guess is for the same reasons I am seeing at command line.

    Edit: Here is messages from system log: ( /var/log/syslog)
    Sep 25 07:10:45 kurt-UP-CHT01 libmraa[1874]: libmraa version v0.5.1-941-g92fdb8a initialised by user 'kurt' with EUID 1000
    Sep 25 07:10:45 kurt-UP-CHT01 libmraa[1874]: libmraa initialised for platform 'UP' of type 12
    Sep 25 07:10:45 kurt-UP-CHT01 libmraa[1874]: gpio14: init: Failed to open 'export' for writing: Permission denied
    Sep 25 07:11:22 kurt-UP-CHT01 libmraa[1875]: libmraa version v0.5.1-941-g92fdb8a initialised by user 'kurt' with EUID 1000
    Sep 25 07:11:22 kurt-UP-CHT01 libmraa[1875]: libmraa initialised for platform 'UP' of type 12
    Sep 25 07:11:22 kurt-UP-CHT01 libmraa[1875]: gpio7: init: Failed to open 'export' for writing: Permission denied
    

    I did a little more playing around as I noticed:
    [email protected]:/sys/class/gpio$ ls -l
    total 0
    --w--w--w- 1 root root 4096 Sep 25 08:10 export
    lrwxrwxrwx 1 root root    0 Sep 25 08:10 gpio26 -> ../../devices/platform/up-pinctrl/gpio/gpio26
    lrwxrwxrwx 1 root root    0 Sep 25 08:07 gpiochip0 -> ../../devices/platform/up-pinctrl/gpio/gpiochip0
    lrwxrwxrwx 1 root root    0 Sep 25 08:07 gpiochip318 -> ../../devices/platform/INT33FF:03/gpio/gpiochip318
    lrwxrwxrwx 1 root root    0 Sep 25 08:07 gpiochip373 -> ../../devices/platform/INT33FF:02/gpio/gpiochip373
    lrwxrwxrwx 1 root root    0 Sep 25 08:07 gpiochip397 -> ../../devices/platform/INT33FF:01/gpio/gpiochip397
    lrwxrwxrwx 1 root root    0 Sep 25 08:07 gpiochip456 -> ../../devices/platform/INT33FF:00/gpio/gpiochip456
    --w------- 1 root root 4096 Sep 25 08:07 unexport
    
    So I tried: chmod 222 export

    Then tried echo 26 > export
    Which worked :D But then tried the next line in the first example which then failed as you can see:
    [email protected]:/sys/class/gpio$ echo 26 > export
    [email protected]:/sys/class/gpio$ ls
    export  gpio26  gpiochip0  gpiochip318  gpiochip373  gpiochip397  gpiochip456  unexport
    [email protected]:/sys/class/gpio$ echo out > /sys/class/gpio/gpio26/direction
    -bash: /sys/class/gpio/gpio26/direction: Permission denied
    [email protected]:/sys/class/gpio$ ls -l
    total 0
    --w--w--w- 1 root root 4096 Sep 25 08:10 export
    lrwxrwxrwx 1 root root    0 Sep 25 08:10 gpio26 -> ../../devices/platform/up-pinctrl/gpio/gpio26
    lrwxrwxrwx 1 root root    0 Sep 25 08:07 gpiochip0 -> ../../devices/platform/up-pinctrl/gpio/gpiochip0
    lrwxrwxrwx 1 root root    0 Sep 25 08:07 gpiochip318 -> ../../devices/platform/INT33FF:03/gpio/gpiochip318
    lrwxrwxrwx 1 root root    0 Sep 25 08:07 gpiochip373 -> ../../devices/platform/INT33FF:02/gpio/gpiochip373
    lrwxrwxrwx 1 root root    0 Sep 25 08:07 gpiochip397 -> ../../devices/platform/INT33FF:01/gpio/gpiochip397
    lrwxrwxrwx 1 root root    0 Sep 25 08:07 gpiochip456 -> ../../devices/platform/INT33FF:00/gpio/gpiochip456
    --w------- 1 root root 4096 Sep 25 08:07 unexport
    [email protected]:/sys/class/gpio$ ls -l gpio26/
    total 0
    -rw-r--r-- 1 root root 4096 Sep 25 08:12 active_low
    lrwxrwxrwx 1 root root    0 Sep 25 08:12 device -> ../../../up-pinctrl
    -rw-r--r-- 1 root root 4096 Sep 25 08:11 direction
    -rw-r--r-- 1 root root 4096 Sep 25 08:12 edge
    drwxr-xr-x 2 root root    0 Sep 25 08:12 power
    lrwxrwxrwx 1 root root    0 Sep 25 08:12 subsystem -> ../../../../../class/gpio
    -rw-r--r-- 1 root root 4096 Sep 25 08:10 uevent
    -rw-r--r-- 1 root root 4096 Sep 25 08:12 value
    
    Again if I do something like: chmod 666 direction
    I can then echo out> direrection
    likewise issue with value...

    My guess is gpiochip0 is not setting up proper permissions. Or not sure if there is some form of /etc/udev/rules.d (or /lib/udev...) file that can be created for this?
  • KurtKurt New Member Posts: 146 ✭✭
    Quick update: I believe that the setting for only root can export GPIO pins appears to be consistent with at least a few other processors on 16.04 including my Odroid XU4. I am curious to look to see if it was this way on earlier versions like 14.04.

    Also appears to be true with at least some version of RPI.

    I was able to run the blink c example of MRAA using Sudo.

    Would be nice to be able to create some form of udev rules or the like that maybe creates it in a new group like GPIO and then add write access for the group, in much the same way as the UARTS are under DIALUP... But will probably continue this later under a new thead.
  • Dan O'DonovanDan O'Donovan Emutex Posts: 227 mod
    Hi Kurt

    Yes, you will need to have root privileges (or use 'sudo') to access the GPIO pins via sysfs.
    For ubilinux, we did look at using udev rules to change the permissions of these files in /sys/class/gpio/..., in a similar way to how RPi does it. It can work, but these files get created dynamically after the "export" and there's a small delay before the udev rules get triggered. If you have a script that tries to access the GPIO immediately after the export (and before the udev rule fires), then it still hits this error and we found that this was causing confusion for end users. So, to keep things simple, we left out those udev rules.

    No memory-mapped GPIO access available at this point. Everything needs to go through sysfs. See this post for details: https://up-community.org/forum/general-discussion/852-native-c-libraries-to-gpio-pins#2235

    -Dan
  • Dan O'DonovanDan O'Donovan Emutex Posts: 227 mod
    Hi Kurt

    Yes, you will need to have root privileges (or use 'sudo') to access the GPIO pins via sysfs.
    For ubilinux, we did look at using udev rules to change the permissions of these files in /sys/class/gpio/..., in a similar way to how RPi does it. It can work, but these files get created dynamically after the "export" and there's a small delay before the udev rules get triggered. If you have a script that tries to access the GPIO immediately after the export (and before the udev rule fires), then it still hits this error and we found that this was causing confusion for end users. So, to keep things simple, we left out those udev rules.

    No memory-mapped GPIO access available at this point. Everything needs to go through sysfs. See this post for details: https://up-community.org/forum/general-discussion/852-native-c-libraries-to-gpio-pins#2235

    -Dan
  • KurtKurt New Member Posts: 146 ✭✭
    Thanks Dan,

    I took a look through and will do some more experimenting .

    I noticed it was stated that the UP is maybe 10 times slower than RPI with GPIO. I wonder how it compares with the Edison...

    Will start new thread later.
  • WK LohWK Loh New Member Posts: 7
    Need help here as I'm struggling with UPBOARD! my GPIO especially UART1 is not working still. I cannot install RPI.GPIO also. anything I missed here to get the UART1 (dev/ttyS1) work?
  • Dan O'DonovanDan O'Donovan Emutex Posts: 227 mod
    Hi

    Are you using Ubuntu with the upboard kernel, or ubilinux? Can you run the 'dmesg' command and attach the output? This might give us some clues.

    Also, the RPi.GPIO module for UP is only included with ubilinux at this time.

    Regards,
    -Dan
  • Chris PolancoChris Polanco New Member Posts: 7
    hey dan,

    I'm having issues with the UART as well I am using Ubuntu with the upboard kernel and i can't get mraa to work. everytime i run my program it gives me the following error:

    File "motorController.py", line 8, in <module>
    transmitter = mraa.Uart(1)
    File "/usr/local/lib/python2.7/dist-packages/mraa.py", line 1181, in __init__
    this = _mraa.new_Uart(*args)
    ValueError: Error initialising UART

    i've tried multiple numbers in mraa.Uart and none work. The Up-board wiki says to use ttyS1 for UART but when i run
    dmesg | grep tty i get the following:

    [ 0.000000] console [tty0] enabled
    [ 1.123350] 00:01: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
    [ 3.555733] 8086228A:00: ttyS4 at MMIO 0xa171b000 (irq = 39, base_baud = 2764800) is a 16550A

    ttyS1 isn't showing on here and I don't know if that's the issue or not. and if it is i'm not sure how to enable the port.

    also, not sure if this is any help but when i run sudo cat /proc/tty/driver/serial i get the following.

    serinfo:1.0 driver revision:
    0: uart:16550A port:000003F8 irq:4 tx:0 rx:0
    1: uart:unknown port:000002F8 irq:3
    2: uart:unknown port:000003E8 irq:4
    3: uart:unknown port:000002E8 irq:3
    4: uart:16550A mmio:0xA171B000 irq:39 tx:0 rx:0
    5: uart:unknown port:00000000 irq:0
    6: uart:unknown port:00000000 irq:0
    7: uart:unknown port:00000000 irq:0
    8: uart:unknown port:00000000 irq:0
    9: uart:unknown port:00000000 irq:0
    10: uart:unknown port:00000000 irq:0
    11: uart:unknown port:00000000 irq:0
    12: uart:unknown port:00000000 irq:0
    13: uart:unknown port:00000000 irq:0
    14: uart:unknown port:00000000 irq:0
    15: uart:unknown port:00000000 irq:0
    16: uart:unknown port:00000000 irq:0
    17: uart:unknown port:00000000 irq:0
    18: uart:unknown port:00000000 irq:0
    19: uart:unknown port:00000000 irq:0
    20: uart:unknown port:00000000 irq:0
    21: uart:unknown port:00000000 irq:0
    22: uart:unknown port:00000000 irq:0
    23: uart:unknown port:00000000 irq:0
    24: uart:unknown port:00000000 irq:0
    25: uart:unknown port:00000000 irq:0
    26: uart:unknown port:00000000 irq:0
    27: uart:unknown port:00000000 irq:0
    28: uart:unknown port:00000000 irq:0
    29: uart:unknown port:00000000 irq:0
    30: uart:unknown port:00000000 irq:0
    31: uart:unknown port:00000000 irq:0

    I want to be able to communicate to my motor controller through serial but can't find out how it works. Any help will do. Thanks in advance.
  • KurtKurt New Member Posts: 146 ✭✭
    Which OS are you using? I am using, I am using 16.04.

    What do you see if you type ls /dev/ttyS*

    When I login in to a KiTTy (Putty) window I see:
    login as: kurt
    [email protected]'s password:
    Welcome to Ubuntu 16.04.1 LTS (GNU/Linux 4.4.0-1-upboard x86_64)
    
     * Documentation:  https://help.ubuntu.com
     * Management:     https://landscape.canonical.com
     * Support:        https://ubuntu.com/advantage
    
    0 packages can be updated.
    0 updates are security updates.
    
    Last login: Fri Oct 14 14:42:08 2016 from 192.168.2.102
    [email protected]:~$ uname -s
    Linux
    [email protected]:~$ uname -a
    Linux kurt-UP-CHT01 4.4.0-1-upboard #10-Ubuntu SMP Fri Sep 23 12:26:42 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
    [email protected]:~$ ls /dev/ttyS*
    /dev/ttyS0  /dev/ttyS1  /dev/ttyS2  /dev/ttyS3
    [email protected]:~$
    
    Note the kernel showing 4.4.0-2-upboard. Does yours say upboard or generic?
    Is your user a member of the dialout group? Example from my machine:
    [email protected]:~$ ls -l /dev/ttyS1
    crw-rw---- 1 root dialout 4, 65 Oct 16 14:34 /dev/ttyS1
    [email protected]:~$ groups
    kurt adm dialout cdrom sudo dip plugdev lpadmin sambashare
    [email protected]:~$
    

    Note: I don't do Python, but have used MRAA in C. Also I have not use mraa for Uarts as when I started using MRAA on edison, the Uart code did not do anything

    Is there anything interesting in the /var/log/syslog file after you run your app? When I get a failure I do something like:
    tail -40 /var/log/syslog
    

    Note: I installed MRAA on my UP from sources.

    Not sure if any of this helps, but...
  • Chris PolancoChris Polanco New Member Posts: 7
    I am using 14.04

    Distributor ID: Ubuntu
    Description: Ubuntu 14.04.5 LTS
    Release: 14.04
    Codename: trusty

    My output for ls /dev/ttyS* is:

    /dev/ttyS0 /dev/ttyS11 /dev/ttyS14 /dev/ttyS17 /dev/ttyS2 /dev/ttyS22 /dev/ttyS25 /dev/ttyS28 /dev/ttyS30 /dev/ttyS5 /dev/ttyS8
    /dev/ttyS1 /dev/ttyS12 /dev/ttyS15 /dev/ttyS18 /dev/ttyS20 /dev/ttyS23 /dev/ttyS26 /dev/ttyS29 /dev/ttyS31 /dev/ttyS6 /dev/ttyS9
    /dev/ttyS10 /dev/ttyS13 /dev/ttyS16 /dev/ttyS19 /dev/ttyS21 /dev/ttyS24 /dev/ttyS27 /dev/ttyS3 /dev/ttyS4 /dev/ttyS7

    [email protected]:~$ uname -s
    Linux
    [email protected]:~$ uname -a
    Linux maverick-UP-CHT01 4.4.0-42-generic #62~14.04.1-Ubuntu SMP Fri Oct 7 23:15:48 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

    how do i change it to cupboard as apposed to generic? can that be the issue?

    I've checked the group and my user is in the dialout group.

    I've used the libmraa with python on the edison on the same motor controller i'm trying to use now and it works.

    my syslog output:

    i tried to run the program again with 8 as the Uart constructor field and got the same error. However, when i did syslog again i got the following:

    Oct 16 17:03:38 maverick-UP-CHT01 libmraa[1862]: libmraa version v1.3.0-7-g8ec4fcb initialised by user 'maverick' with EUID 1000
    Oct 16 17:03:38 maverick-UP-CHT01 libmraa[1862]: libmraa initialised for platform 'UP' of type 12
    Oct 16 17:03:38 maverick-UP-CHT01 libmraa[1862]: uart8: init: platform has only 2 uarts

    Then i ran again with 0 as the Uart constructor field (i saw this in an example python program in this repository) and got the following.

    Oct 16 17:06:06 maverick-UP-CHT01 libmraa[1875]: libmraa version v1.3.0-7-g8ec4fcb initialised by user 'maverick' with EUID 1000
    Oct 16 17:06:06 maverick-UP-CHT01 libmraa[1875]: libmraa initialised for platform 'UP' of type 12
    Oct 16 17:06:06 maverick-UP-CHT01 libmraa[1875]: uart: tcgetattr(/dev/ttyS1) failed: Input/output error
  • KurtKurt New Member Posts: 146 ✭✭
    [email protected]:~$ uname -a
    Linux maverick-UP-CHT01 4.4.0-42-generic #62~14.04.1-Ubuntu SMP Fri Oct 7 23:15:48 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

    how do i change it to cupboard as apposed to generic? can that be the issue?
    My guess is yes, that is the issue.

    I followed the steps in the wiki: https://up-community.org/wiki/Ubuntu
    I did option 1, which did: sudo apt-get autoremove --purge 'linux-.*generic'
  • Chris PolancoChris Polanco New Member Posts: 7
    i followed the instructions to remove the generic however my up kernel is out of date and i can't seem to update it. i have 4.2 and it's at 4.4. i followed the instructions given here https://up-community.org/wiki/Ubuntu however it just keeps the current.
  • DCleriDCleri Administrator, AAEON Posts: 644 admin
    if the upgrade doesn't work, please install manually the 4.4 kernel on Trusty with the command:

    sudo apt-get isntall linux-upboard-lts-xenial

    Then you can proceed and remove the generic kernel as suggested here: https://up-community.org/wiki/Ubuntu
  • Chris PolancoChris Polanco New Member Posts: 7
    I saw that but wasn't sure i could install that one since i'm using Trusty. I'll try it now and let you know how it goes.
  • Chris PolancoChris Polanco New Member Posts: 7
    The kernel update fixed the problem thank you.
  • MarcelloMarcello New Member Posts: 156
    DCleri wrote:
    New Ubuntu 14.04 and Ubuntu 16.04 4.4 Kernel packages for the UP...

    Hi dcleri, any plans for an upgraded kernel at some point? This is 4.4.0-1 and has some issues in detecting devices. For example it randomly detects my webcam microphone. 4.4.0-38/43 don't have this issue...
    let us know... thanks.
  • MarioMario New Member Posts: 9
    Hello Dan
    The udev rules you mentioned for ubilinux. Is there a way to implement them into the upboard linux kernel. The problem in my case is that I don't only need to sudo execute the code I want to run, but also export some environmental variables as super user (This includes some paths to shared libraries). My code (ROS node) is also part of a larger launch chain which complicates things even more by requiring password. I'm currently doing this with a shell script, but I believe this is a very inelegant solution. It would be nice as KurtE mentioned to have some rules for GPIO and to simply add a user to a group to access it.
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