[beagleboard] How to deactivate automatic cape detection to free addresses on I2C-2

[Beagle Boner]

Hi,

i am using Debian Jessie on my BBB. I need to connect a I²C device to it. 
Unfortunatly it has a fixed address at 0x54, which is one of the addresses 
used to read the epromdata on capes for automatic dto loading. I can´t use 
the other I²C-1 for this project, so I am forced to disable the eprom 
reading and address reservation somehow. Do you guys have any ideas how I 
could achieve that? Do I need to make my own device tree for that or is 
there a way more simple?

Cheers

Max

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[beagleboard] BeagleBone Green Wireless turns itself off after 10-40 seconds

[Alek Mabry]

Hello!

My BBGW consistently turns itself off, no matter what power supply or image 
I use. It consistently acted the same on both of my BBGW. 

With default factory configuration:
https://youtu.be/fBhOSkkfCps

With latest image (Debian 8.6 2016-11-06 4GB SD SeeedStudio IoT  
image
 
for SeeedStudio BeagleBone Green Wireless 
):
https://youtu.be/nRTk8SZuWlI

Somehow I can get it to work if I plug my serial connector in. But then 
after the stage where the BBGW shuts off the LED pattern flashes like this:

On | Off | On | Off
Off | On | Off| On

I am able to connect to the board in this stage. I've tested both 500ma and 
1A USB chargers and none of them seem to work.

Thanks for any help,
Alek

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[beagleboard] Re: Error using connmanctl> enable wifi BBBW

[mostafa . bahrami2013]

Hi robert. I have the same problem. I download latest image for bbbw from 
beagle site(debian 9.1 2017.10.10). When i try to enable wifi by connmanctl, i 
recieved below error.
Error wifi : methode "set property" with signature "sv" on interface 
"net.connman.technologies" doesn't exist.

What is the reason? 

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[beagleboard] Re: BeagleBone Green Wireless turns itself off after 10-40 seconds

[drhunter95]

Hi Alek,
I think you need more than a 1A supply. I use one of these 
https://www.amazon.co.uk/Charger-RAVPower-4-Port-Charge-Smartphones-White/dp/B018Q7HNRQ/ref=sr_1_4
 to power 4 BBGWs.
I suspect the board is suffering a brown out when the WL1835 does its short 
calibration (a couple of ms but at ~500mA).
Iain

On Tuesday, 9 January 2018 13:27:52 UTC, Alek Mabry wrote:
>
>
> Hello!
>
> My BBGW consistently turns itself off, no matter what power supply or 
> image I use. It consistently acted the same on both of my BBGW. 
>
> With default factory configuration:
> https://youtu.be/fBhOSkkfCps
>
> With latest image (Debian 8.6 2016-11-06 4GB SD SeeedStudio IoT  
> image
>  
> for SeeedStudio BeagleBone Green Wireless 
> ):
> https://youtu.be/nRTk8SZuWlI
>
> Somehow I can get it to work if I plug my serial connector in. But then 
> after the stage where the BBGW shuts off the LED pattern flashes like this:
>
> On | Off | On | Off
> Off | On | Off| On
>
> I am able to connect to the board in this stage. I've tested both 500ma 
> and 1A USB chargers and none of them seem to work.
>
> Thanks for any help,
> Alek
>

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Re: [beagleboard] Does Spectre and Meltdown affect Beaglebone Black?

[Jason Kridner]

TI's note on Meltdown and Spectre:

http://e2e.ti.com/support/arm/sitara_arm/f/791/t/654938


On Sun, Jan 7, 2018 at 9:22 PM Robert Nelson 
wrote:

> On Sun, Jan 7, 2018 at 8:19 PM, Robert Nelson 
> wrote:
> >> One useful mitigation:
> >>
> http://lists.infradead.org/pipermail/linux-arm-kernel/2018-January/552243.html
> >
> > Okay, that's a lot better..
> >
> > From ARM's website, it really looked like ARM didn't care about the
> > arm32 (A8/A9/A15/A17) family...
>
> PS, it would be nice to see a proof of concept exploit on the A8, then
> we can prove
> those mitigation actually work.. ;)
>
> Regards,
>
> --
> Robert Nelson
> https://rcn-ee.com/
>
> --
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[beagleboard] Re: How to perform "factory reset"

[Bryan Hughes]

Did you ever find the answer?

Thanks

On Sunday, October 29, 2017 at 10:26:23 AM UTC-7, Walter Greger wrote:
>
> Hi there,
>
> I owned a Beaglebone Green Wireless. I have some troubles to connect the 
> beagle to my wifi. I tried so many thing without success. However, my 
> settings seems to be broken. Now I try to reset the beagle completly. I 
> flashed the latest image file on the beagle (on eMMC) but the user settings 
> are still the same. How do I come to "clean" beagle?
>
> Kind regards
>

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[beagleboard] Re: How to deactivate automatic cape detection to free addresses on I2C-2

[Graham]

Search for emails with topic "BBB without Cape Manager"
--- Graham

==

On Tuesday, January 9, 2018 at 3:24:04 AM UTC-6, Beagle Boner wrote:
>
> Hi,
>
> i am using Debian Jessie on my BBB. I need to connect a I²C device to it. 
> Unfortunatly it has a fixed address at 0x54, which is one of the addresses 
> used to read the epromdata on capes for automatic dto loading. I can´t use 
> the other I²C-1 for this project, so I am forced to disable the eprom 
> reading and address reservation somehow. Do you guys have any ideas how I 
> could achieve that? Do I need to make my own device tree for that or is 
> there a way more simple?
>
> Cheers
>
> Max
>

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Re: [beagleboard] How to replace 4.4.x Linux kernel in BBB eMMC after cross compiling from source?

[Dennis K]

Robert,

Thanks that was just what I needed.
I have successfully rebooted the system with the new kernel.

I did have to do some more research since I had neglected to compile and 
install the modules to a folder, but I was able to get through that.

One thing that bothers me is whether I need to do anything about the kernel 
headers.

I was wondering since I still can not access /dev/mem.
There is something locking me out that I need to find and change.

I know that the c program that I have to access /dev/mem works since I was 
able to get it to work with an older kernel but I was forced to upgrade 
because with the older kernel the pru_rproc driver did not work.

Dennis

On Friday, January 5, 2018 at 4:08:14 PM UTC-5, RobertCNelson wrote:
>
> On Fri, Jan 5, 2018 at 2:59 PM, Dennis K  > wrote: 
> > 
> > I need to recompile my current Beaglebone Black Linux kernel (4.4.91) to 
> set 
> > CONFIG_STRICT_DEVMEM=n. 
> > This will allow the use of mmap to access the SPI interface hardware 
> > directly, among other things. 
> > 
> > So far... 
> > I have loaded the latest version of arm-linux-gnueabihf gcc. 
> > Cloned the latest kernel source (
> https://github.com/beagleboard/linux/git) 
> > which is currently 4.4.91. 
> > Modified the kernel config options to set CONFIG_STRICT_DEVMEM=n. 
> > Compiled the kernel. 
> > Cloned, patched, and compiled u-boot. 
> > 
> > At this point the instructions that I have been following diverge and 
> are 
> > more concerned with creating a bootable image 
> > on the SD card for testing or for replacing the entire contents of the 
> eMMC 
> > on the Beaglebone. 
> > 
> > What I want to do is replace the existing kernel on eMMC with minimal 
> impact 
> > to the current configuration. 
> > My current filesystem is BeagleBoard.org Debian Image 2016-05-13. 
> > 
> > Can someone explain the process to replace the kernel on eMMC? 
>
> First cat ./include/generated/utsrelease.h in your build directory: 
>
> You'll see something similar like: 
>
> #define UTS_RELEASE "4.14.12-4-gdb0cd0519e45" 
>
> That's your Kernel Version, then just follow this: 
>
> Copy zImage to /boot/vmlinuz-`Kernel Version` 
> Copy *.dtb to /boot/dtbs/`Kernel Version`/ 
> Copy modules to /lib/modules/`Kernel Version` 
> Edit /boot/uEnv.txt and update uname_r=`Kernel Version` 
>
> Regards, 
>
> -- 
> Robert Nelson 
> https://rcn-ee.com/ 
>

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[beagleboard] Back Fill Position || Urgent Need Performance Tester (Memphis, TN) 18+ Months

[Javeed Khan]

Please share profile on ja...@nestarit.com

Direct contact number: (201) 448 1184



This is *Javed Khan* from *NESTAR TECHNOLOGIES/ AESPATECH LLC* and we have
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can close the positions pretty quick. If you find yourself comfortable with
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back to you or

I would really appreciate if you can give me a call back at my contact
number.



We have a Requirement *Performance Tester* position in *Memphis, TN,*



VERY URGENT AND IMMEDIATE NEED



Job Title: Performance Tester

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Duration: 18+ Months Contract



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SoapUI, LoadUI, JIRA and Selenium automation. Any additional experience on
any other automation tools is a plus.





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*Date Last Used(MM/)*

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JMeter (an Apache product) – performance/ load testing

BlazeMeter – performance/load testing

SoapUI, LoadUI

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SQL queries – backend testing





*Submissions Details*

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*NESTAR TECHNOLOGIES/ AESPATECH LLC*

Direct: (201) 448-1153

Email: ja...@nestarit.com

Skype ID: javeedkhan.khan2

GTalk: javeedimrank...@gmail.com   ; javednesta...@gmail.com

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*Notice of Confidentiality:*

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[beagleboard] HDMI not working for particular display

[krishanv911]

I am getting display output when I connect BBB to 32 inch LG display while 
running default OS as well as with Ubuntu 12.04 on SD card
But when i connect BBB to Worldtech WT-1188U display i get NO Signal 
notification on display.

Tried changing HDMI resolution in uEnv.txt didn't work out.

Need help.

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Re: [beagleboard] HDMI not working for particular display

[Robert Nelson]

On Tue, Jan 9, 2018 at 4:53 PM,   wrote:
> I am getting display output when I connect BBB to 32 inch LG display while
> running default OS as well as with Ubuntu 12.04 on SD card
> But when i connect BBB to Worldtech WT-1188U display i get NO Signal
> notification on display.
>
> Tried changing HDMI resolution in uEnv.txt didn't work out.
>
> Need help.

Do you have a common ground between the BBB and Worldtech display?

Regards,

-- 
Robert Nelson
https://rcn-ee.com/

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Re: [beagleboard] fbdev and ssd1306

[David Lechner]

Sounds like a question for RCN. I'm not up to speed on the pinctrl situation on 
BeagleBone. I'm weird and don't use capemanager or any of the usual BealgeBone 
stuff.

But, I think you are right to think the problem is cause by pin muxing somehow.


On 01/09/2018 12:41 AM, Mark Grosen wrote:

I moved 4.14.12-ti-r24 and now it gets past the the vbat regulator, but then 
fails trying to write to the I2C with a bus ready timeout:

mark@pocket:~/bb.org-overlays/src/arm$ dmesg | grep -P 'ssd|i2c'
[    0.508117] omap_i2c 44e0b000.i2c: could not find pctldev for node 
/ocp/l4_wkup@44c0/scm@21/pinmux@800/pinmux_i2c0_pins, deferring probe
[    0.509098] omap_i2c 4802a000.i2c: bus 1 rev0.11 at 400 kHz
[    0.509821] omap_i2c 4819c000.i2c: bus 2 rev0.11 at 400 kHz
[    1.945474] omap_i2c 4802a000.i2c: timeout waiting for bus ready
[    1.945496] ssd1307fb 1-003c: Couldn't send I2C command 2.
[    1.945554] ssd1307fb: probe of 1-003c failed with error -110
[    2.057076] i2c /dev entries driver
[    2.178366] input: tps65217_pwr_but as 
/devices/platform/ocp/44e0b000.i2c/i2c-0/0-0024/tps65217-pwrbutton/input/input0
[    2.179568] omap_i2c 44e0b000.i2c: bus 0 rev0.11 at 400 kHz

After the boot finishes, I can use the device from userspace with no problems. 
It seems that i2c-1 is registered before the ssd1307fb probe happens. Are pins 
not assigned at this point?

Mark

On Mon, Jan 8, 2018 at 7:10 PM David Lechner mailto:da...@lechnology.com>> wrote:

The linux driver for this is an i2c driver. So the device tree node that you added 
will create an i2c device in the linux kernel (i.e. /sys/bus/i2c/devices/1-003c). Then 
udev sees that this device matches the compatible string of the "ssd1307fb" 
driver (you will see this listed in `lsmod`). This driver is bound to the device and 
calls the drivers probe function. This is where the error message is coming from. If the 
probe function had completed successfully, it would have registered a new fbdev device.

It looks like this error is a bug in the linux kernel that was fixed in kernel v4.11. 
 
.

You can work around this by adding a fixed regulator to the device tree and 
adding it to your device. Or, if you are compiling your own kernel anyway, you 
can grab the patch I linked.


On 1/8/18 8:09 PM, Mark Grosen wrote:

mark@pocket:~$ dmesg | grep -P 'fb|ssd'
[    2.165499] ssd1307fb 1-003c: failed to get VBAT regulator: -19

How does fbdev "find" the ssd1306?

On Mon, Jan 8, 2018 at 5:51 PM David Lechner mailto:da...@lechnology.com>> wrote:

On 01/08/2018 07:27 PM, Mark Grosen wrote:

On Mon, Jan 8, 2018 at 10:08 AM David Lechner mailto:da...@lechnology.com>> wrote:

On 01/07/2018 05:59 PM, Mark Grosen wrote:
> I am trying to get the kernel driver for the ssd1306 working with 
the PocketBeagle USB HUB cape which has a 64x32 SSD1306 display 
(https://www.tindie.com/products/microwavemont/oled-with-24-port-usb-hub-cape-for-pocketbeagle/)
 I know it is physically working as I can use it via user-mode I2C. I believe a 
small change is needed to support the unusual 64 pixel width of this board. I have 
built and loaded a new kernel and have a .dtbo

And what does your device tree overlay look like?


/dts-v1/;
/plugin/;

#include 
#include 
#include 

/ {
fragment@0 {
target = <&i2c1>;
__overlay__ {
status = "okay";

#address-cells = <1>;
#size-cells = <0>;

ssd1306: oled@3c {
compatible = "solomon,ssd1306fb-i2c";
reg = <0x3c>;
solomon,width = <64>;
solomon,height = <32>;
solomon,page-offset = <0>;
};
};
};
};


> loaded via u-boot with 4.4.88-ti-r128 kernel. It shows up in 
/proc/device-tree correctly (at least as far as I can tell - the entries match the 
dts values). I am missing how to get this connected to the framebuffer world - 
there is no /dev/fb0 showing up. I see the config options appear to be enabled (I 
am using the defconfig).

And which options did you enable/are enabled?


mark@pocket:~$ zcat /proc/config.gz | grep CONFIG_FB | grep -v '#'
CONFIG_FB=y
CONFIG_FB_CMDLINE=y
CONFIG_FB_NOTIFY=y
CONFIG_FB_CFB_FILLRECT=y
CONFIG_FB_CFB_COPYAREA=y
CONFIG_FB_CFB_IMAGEBLIT=y
CONFIG_FB_SYS_FILLRECT=y
CONFIG_FB_SYS_COPYAREA=y
CONFIG_FB_SYS_IMAGEBLIT=y
CONFIG_FB_SYS_FOPS=y
CONFIG_FB_DEFERRED_IO=y
CONFIG_FB_BACKLIGHT=y
CONFIG_FB_MODE_HELPERS=y
CONFIG_FB_TILEBLITTING=y
CONFIG_FB_SMSCUFX=m
CONFIG_FB_UDL=m
CONFIG_FB_SIMPLE=y
CONFIG_FB_SSD1307=y



Looks alright to me. 

Re: [beagleboard] fbdev and ssd1306

[Mark Grosen]

Thanks, David. I am not competent enough on DT yet. I see one of the I2C
devices has a pinctrl in the device-tree but i2c1 does not. I don't
understand why/how when I open /dev/i2c-1 from userspace that the pins seem
to get assigned. Hopefully Robert can help.

Mark

On Tue, Jan 9, 2018 at 7:26 PM David Lechner  wrote:

> Sounds like a question for RCN. I'm not up to speed on the pinctrl
> situation on BeagleBone. I'm weird and don't use capemanager or any of the
> usual BealgeBone stuff.
>
> But, I think you are right to think the problem is cause by pin muxing
> somehow.
>
>
>
> On 01/09/2018 12:41 AM, Mark Grosen wrote:
>
> I moved 4.14.12-ti-r24 and now it gets past the the vbat regulator, but
> then fails trying to write to the I2C with a bus ready timeout:
>
> mark@pocket:~/bb.org-overlays/src/arm$ dmesg | grep -P 'ssd|i2c'
> [0.508117] omap_i2c 44e0b000.i2c: could not find pctldev for node
> /ocp/l4_wkup@44c0/scm@21/pinmux@800/pinmux_i2c0_pins, deferring
> probe
> [0.509098] omap_i2c 4802a000.i2c: bus 1 rev0.11 at 400 kHz
> [0.509821] omap_i2c 4819c000.i2c: bus 2 rev0.11 at 400 kHz
> [1.945474] omap_i2c 4802a000.i2c: timeout waiting for bus ready
> [1.945496] ssd1307fb 1-003c: Couldn't send I2C command 2.
> [1.945554] ssd1307fb: probe of 1-003c failed with error -110
> [2.057076] i2c /dev entries driver
> [2.178366] input: tps65217_pwr_but as
> /devices/platform/ocp/44e0b000.i2c/i2c-0/0-0024/tps65217-pwrbutton/input/input0
> [2.179568] omap_i2c 44e0b000.i2c: bus 0 rev0.11 at 400 kHz
>
> After the boot finishes, I can use the device from userspace with no
> problems. It seems that i2c-1 is registered before the ssd1307fb probe
> happens. Are pins not assigned at this point?
>
> Mark
>
> On Mon, Jan 8, 2018 at 7:10 PM David Lechner  wrote:
>
>> The linux driver for this is an i2c driver. So the device tree node that
>> you added will create an i2c device in the linux kernel (i.e.
>> /sys/bus/i2c/devices/1-003c). Then udev sees that this device matches the
>> compatible string of the "ssd1307fb" driver (you will see this listed in
>> `lsmod`). This driver is bound to the device and calls the drivers probe
>> function. This is where the error message is coming from. If the probe
>> function had completed successfully, it would have registered a new fbdev
>> device.
>>
>> It looks like this error is a bug in the linux kernel that was fixed in
>> kernel v4.11.
>> 
>> 
>> .
>>
>> You can work around this by adding a fixed regulator to the device tree
>> and adding it to your device. Or, if you are compiling your own kernel
>> anyway, you can grab the patch I linked.
>>
>> On 1/8/18 8:09 PM, Mark Grosen wrote:
>>
>> mark@pocket:~$ dmesg | grep -P 'fb|ssd'
>> [2.165499] ssd1307fb 1-003c: failed to get VBAT regulator: -19
>>
>> How does fbdev "find" the ssd1306?
>>
>> On Mon, Jan 8, 2018 at 5:51 PM David Lechner 
>> wrote:
>>
>>> On 01/08/2018 07:27 PM, Mark Grosen wrote:
>>>
>>> On Mon, Jan 8, 2018 at 10:08 AM David Lechner 
>>> wrote:
>>>
 On 01/07/2018 05:59 PM, Mark Grosen wrote:
 > I am trying to get the kernel driver for the ssd1306 working with the
 PocketBeagle USB HUB cape which has a 64x32 SSD1306 display (
 https://www.tindie.com/products/microwavemont/oled-with-24-port-usb-hub-cape-for-pocketbeagle/)
 I know it is physically working as I can use it via user-mode I2C. I
 believe a small change is needed to support the unusual 64 pixel width of
 this board. I have built and loaded a new kernel and have a .dtbo

 And what does your device tree overlay look like?

>>>
>>> /dts-v1/;
>>> /plugin/;
>>>
>>> #include 
>>> #include 
>>> #include 
>>>
>>> / {
>>> fragment@0 {
>>> target = <&i2c1>;
>>> __overlay__ {
>>> status = "okay";
>>>
>>> #address-cells = <1>;
>>> #size-cells = <0>;
>>>
>>> ssd1306: oled@3c {
>>> compatible = "solomon,ssd1306fb-i2c";
>>> reg = <0x3c>;
>>> solomon,width = <64>;
>>> solomon,height = <32>;
>>> solomon,page-offset = <0>;
>>> };
>>> };
>>> };
>>> };
>>>
>>>

 > loaded via u-boot with 4.4.88-ti-r128 kernel. It shows up in
 /proc/device-tree correctly (at least as far as I can tell - the entries
 match the dts values). I am missing how to get this connected to the
 framebuffer world - there is no /dev/fb0 showing up. I see the config
 options appear to be enabled (I am using the defconfig).

 And which options did you enable/are enabled?
>>>
>>>
>>> mark@pocket:~$ zcat /proc/config.gz | grep CONFIG_FB | grep -v '#'
>>> CONFIG_FB=y
>>> CONFIG_FB_CMDLINE=y
>>> CONFIG_FB_NOTIFY=y
>>> CONFIG_FB_CFB_FILLRECT=y
>>> CONFIG_FB_CFB_COPYAREA=y
>>> CONFIG_FB_CFB_IMAGEBLIT=y
>>> CONFIG_FB_SYS_FILLRECT=y
>>> CONFIG