EmbLogic » mks https://www.emblogic.com/blog Embedded System and ARM Training Tue, 03 Mar 2020 13:00:06 +0000 en-US hourly 1 http://wordpress.org/?v=3.9.1 lsmod Analysis https://www.emblogic.com/blog/08/lsmod-analysis/ https://www.emblogic.com/blog/08/lsmod-analysis/#comments Thu, 16 Aug 2012 13:02:04 +0000 http://emblogic.org/blog/?p=4773 lsmod has column used i.e module using the lkm (that particular lkm) . My system showing value -1 for module ipv6 then what -1 signifies ?

Used = 0 means no module using this lkm

]]> https://www.emblogic.com/blog/08/lsmod-analysis/feed/ 0 Hot Swap In Linux kernel https://www.emblogic.com/blog/08/hot-swap-in-linux-kernel/ https://www.emblogic.com/blog/08/hot-swap-in-linux-kernel/#comments Thu, 16 Aug 2012 12:56:08 +0000 http://emblogic.org/blog/?p=4771 What is the difference between hot swap and hot plug ? How it is implemented in linux kernel 2.4.x ? Is linux kernel 2.4.x supports hot plug also ?

]]> https://www.emblogic.com/blog/08/hot-swap-in-linux-kernel/feed/ 3 Platform Driver !! https://www.emblogic.com/blog/04/platform-driver/ https://www.emblogic.com/blog/04/platform-driver/#comments Wed, 20 Apr 2011 08:13:58 +0000 http://emblogic.org/blog/?p=648 Continue reading →]]> Driver Model (USB,I2C) enumerate device and bind it with driver .USB and PCI are hotplugged device and they have capability to notify OS when lets say USB (pendrive )attach.But in SOC’s based , a lot of inbuilt peripherals like host controller(eg i2c HC) these inbuilt devices are not capable to inform the OS that they are present. So the kernel/drivers developers built similar model like hot pluggable devices so they invented platform drivers model.

]]> https://www.emblogic.com/blog/04/platform-driver/feed/ 1 Kmalloc failed to allocate ? https://www.emblogic.com/blog/04/kmalloc-failed-to-allocate/ https://www.emblogic.com/blog/04/kmalloc-failed-to-allocate/#comments Tue, 19 Apr 2011 06:37:47 +0000 http://emblogic.org/blog/?p=645 Continue reading →]]> Lets say we have device mobile and we start an application ,our application connects to our driver and in driver level lets say we allocate some memory using kmalloc with flag=GFP_KERNEL ,now if memory allocation fail in each time so what will be our application behaviour,will it run or will crash ,how memory issue will resolve and what are the likely cause of failure? Secondly ,if I put into different way like suppose ,I use kmalloc in ISR then again lets say our memory allocation fail (with some reason) then what are the issues we have to address and Will our application crash or we just flash “memory fail switch off your mobile ….”

]]> https://www.emblogic.com/blog/04/kmalloc-failed-to-allocate/feed/ 1 Inside structure declaration of variable of same type is not allowed https://www.emblogic.com/blog/10/inside-structure-declaration-of-variable-of-same-type-is-not-allowed/ https://www.emblogic.com/blog/10/inside-structure-declaration-of-variable-of-same-type-is-not-allowed/#comments Tue, 19 Oct 2010 09:35:14 +0000 http://emblogic.org/blog/?p=227 struct node { struct node x; //not allowed struct node *head; //allowed }; Why does we can declare a pointer of same type but not a variable of same type? ]]> https://www.emblogic.com/blog/10/inside-structure-declaration-of-variable-of-same-type-is-not-allowed/feed/ 1 Alternative method of newline https://www.emblogic.com/blog/10/alternative-method-of-newline/ https://www.emblogic.com/blog/10/alternative-method-of-newline/#comments Mon, 18 Oct 2010 10:27:14 +0000 http://emblogic.org/blog/?p=222 Q. How to print output in multiple line without using \n character?

Ans. printf(“\x0a”);

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