adb shell command to Turn ON Bluetooth & make it discoverable

bluetooth

We can turn on the Bluetooth using adb command as below, once you type this on your desktop/laptop, Android will prompt the user on Mobile / Android device for allowing permissions to turn ON the bluetooth, like below We can make the Bluetooth Discoverable using adb command as below, Subscribe with Valid Email Id to … Read more

Writing first Linux kernel Module

We will try to understand the simple kernel driver which initially we will compile for Ubuntu host and later for a embedded hardware. Create a Makefile, [Note: Make sure you have added TAB before “make” in above makefile ] Now, compile this kernel module for Ubuntu based host, The “tree” command shows the output files … Read more

How to Enable and Disable Wireless / WiFi from command line ?

Rfkill is a tool for enabling and disabling wireless devices. We use “rfkill list” command as below to check the list of available wireless devices on our machine. This command returns the devices and its index 0, 1, 2 as below, As seen above we have a WiFi, LAN and Bluetooth supported and ON in … Read more

How to Turn ON and Turn OFF Bluetooth from command line ?

Rfkill is a tool for enabling and disabling wireless devices. Using “rfkill list” command we first check the list of available wireless devices supported in our hardware as, As seen above we have a WiFi, LAN and Bluetooth supported and ON in my laptop. Now lets try turning ON & OFF this Bluetooth device using … Read more

How to extract files from jffs2 root filesystem image ?

[ Note: following commands has been tried on ubuntu 16.04, but should work on other Linux distros as well ] Lets create a temporary device node in /tmp as, brw-r–r– 1 root root 31, 0 Aug 23 00:21 /tmp/mtdblock0 Now lets use dd command to write jffs2 binary rootfs to temporary device node we created … Read more

Creating jffs2 filesystem image for embedded target platform

What is JFFS2 ?=> JFFS2 is a log-structured file system designed for use on flash devices in embedded systems. Rather than using a kind of translation layer on flash devices to emulate a normal hard drive, as is the case with older flash solutions, it places the filesystem directly on the flash chips.JFFS2 was developed … Read more

How to Join Linux kernel mailing lists (LKML) ?

LKML https://lkml.org/ is an unofficial Linux Kernel Mailing List archive. This mailing list is a rather high-volume list, where (technical) discussions on the design of, and bugs in the Linux kernel take place. You can read more information about it at http://vger.kernel.org/lkml/ How to join Linux kernel mailing lists ? Linux kernel has different mailing … Read more

How to Compile and Install device-tree-compiler (DTC) On Ubuntu ?

If you want to install device-tree-compiler i.e. dtc command on Ubuntu, use following command, This command will install two command “dtc” and “dtdiff” of which dtc is a device tree compiler whereas dtdiff helps to take diff between two device tree source files. The source code of DTC is available at https://git.kernel.org/pub/scm/utils/dtc/dtc.git . You can … Read more

How to compile DTS to DTB from Linux kernel and manually ?

Lets say, you have been trying to compile Linux kernel source code for Raspberry Pi following steps from “Cross Compilation and Booting of Linux kernel for Raspberry Pi3 – Manual Compilation” although most of the steps remains same in general for other ARM architectures as well , so just replace Raspberry Pi name with your … Read more