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Write and Submit

your first LinuxKernel Patch

Greg Kroah-Hartmangregkh@linuxfoundation.org

github.com/gregkh/kernel-tutorial.git

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Documentation/HOWTO

Documentation/development_process

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git remote add linux-next \

git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.g

git fetch linux-next

git fetch --tags linux-next

.. # later on

git remote update

Working with linux-next

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Linux Kernel Coding Style

Why Care?

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It is not merely a matter of aesthetics thatprograms should be written in a particularstyle. Rather there is a psychological basis forwriting programs in a conventional manner:programmers have strong expectations thatother programmers will follow thesediscourse rules. If the rules are violated, thenthe utility afforded by the expectations thatprogrammers have built up over time is

effectively nullified. Soloway & Ehrlich

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Documentation/CodingStyl

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scripts/checkpatch.p

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SB: otg: Fix bug on remove path without transceiver

n the case where a gadget driver is removed while noransceiver was found at probe time, a bug intg_put_transceiver() will trigger.

gned-off-by: Robert Jarzmik cked-by: David Brownell dev);

if (x)put_device(x->dev);

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Developer's Certificate of Origin

(a) I created this change; or

(b) Based this on a previous work with acompatible license; or

(c) Provided to me by (a), (b), or (c) and notmodified

(d) This contribution is public.

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git diff

git commit

git show

git format-patch

git send-email

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scripts/get_maintainer.p

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Checklist Kernel builds with patch applied

Correct From: address

Concise Subject:

Explain the patch

Signed-off-by

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2.6.20 to 2.6.2

kernelnewbies.org

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Write and Submit

your first LinuxKernel Patch

Greg Kroah-Hartman

gregkh@linuxfoundation.orggithub.com/gregkh/kernel-tutorial.git

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Documentation/HOWTO

Documentation/development_process

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$ git remote add linux-next \git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

$ git fetch linux-next

$ git fetch --tags linux-next

... # later on

$ git remote update

Working with linux-next

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Linux Kernel Coding Style

Why Care?

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Documentation/CodingStyle

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scripts/checkpatch.pl

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USB: otg: Fix bug on remove path without transceiverIn the case where a gadget driver is removed while notransceiver was found at probe time, a bug inotg_put_transceiver() will trigger.

Signed-off-by: Robert Jarzmik Acked-by: David Brownell Signed-off-by: Greg Kroah-Hartman

--- a/drivers/usb/otg/otg.c+++ b/drivers/usb/otg/otg.c@@ -43,7 +43,8 @@ EXPORT_SYMBOL(otg_get_transceiver);void otg_put_transceiver(struct otg_transceiver *x){- put_device(x->dev);+ if (x)+ put_device(x->dev);

}

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Developer's Certificate of Origin

(a) I created this change; or

(b) Based this on a previous work with acompatible license; or

(c) Provided to me by (a), (b), or (c) and notmodified

(d) This contribution is public.

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git diff

git commit

git show

git format-patch

git send-email

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scripts/get_maintainer.pl

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Checklist

Kernel builds with patch applied Correct From: address

Concise Subject:

Explain the patch

Signed-off-by

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2.6.20 to 2.6.24-rc8

kernelnewbies.org

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