April 2018 - kernelnewbies@kernelnewbies.org - Kernelnewbies Mailing Lists

LKCAMP - Linux Kernel Study Group - English subtitles
by Helen Fornazier April 3, 2018

April 3, 2018

Hi kernelnewbies community, First I would like to say thanks for your support helping answering questions from the LKCAMP group. We are recording the talks from our group, and I would like to inform that for those who don't speak Portuguese, we are have really awesome volunteers who wrote subtitles in English for the videos to facilitate remote participation (Thanks Lucas Magalhães and Andrew Chuang). So if you want to get started in Linux Kernel development, check out our study group: M1 - https://youtu.be/YKARS9Sz-Cc M2 - https://youtu.be/T4QNorHHkbk More information about the group: https://goo.gl/Y4zVUZ Regards Helen Koike -- LKCAMP is a Linux Kernel study group organized at University of Campinas (Unicamp) to help anyone to get started in kernel development. Meetings every Tuesday night at 19h GMT-3 (Sao Paulo Brazil). Live stream at the University YouTube channel: https://www.youtube.com/channel/UCraCE6iWUcFCJSp-vmO1D3A We don't grant that we will have the English subtitles as soon as the video is released (we are volunteers), but we are going to announce at the mailing list lkcamp(a)lists.libreplanetbr.org (most messages are in portuguese, sorry about that, if several people from all over the world start to participate we can change that). Instructions to subscribe at this list is written in the document above.

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V4l2 Sensor driver and V4l2 ctrls
by MUHAMMED ASAD P T April 3, 2018

April 3, 2018

Hi All, In reference sensor drivers, they used the V4L2_CID_DV_RX_POWER_PRESENT v4l2 ctrl. It is a standard ctrl and created using v4l2_ctrl_new_std(). The doubts are: 1. Whether in our sensor driver, we need to create this Control Id or not. How to take the decision on this. Since this is the standard ctrl. When we need to use these standard ctrls?? 2. In Sensor driver, the ctrls creation is anything depends on the bridge driver. Based on bridge driver, whether we need to create any ctrls in Sensor driver. This question belongs to design of the sensor driver. Thanks & Regards - Asad IQ Root Technologies

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Difference between atomic context and interrupt context.
by Madhu K April 2, 2018

April 2, 2018

Hi All, what is the difference between atomic context and interrupt context. are they both same? regards, Madhu

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Set SO_TCP_NODELAY (disabling the Nagle Algorithm)
by Naruto Nguyen April 1, 2018

April 1, 2018

Hello everyone, As I know we have a socket option SO_TCP_NODELAY to disable Nagle Algorithm, and I found it is implemented in TCP/IP stack at https://elixir.bootlin.com/linux/v4.4.90/source/net/ipv4/tcp.c#L2401 . However, I do not know where the source code the Nagle Algorithm is implemented in kernel. If you know, could you please help me? Brs, Naruto

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