From mboxrd@z Thu Jan  1 00:00:00 1970
From: milton@krutt.org (Milton Krutt)
Date: Mon, 23 Mar 2015 05:18:45 -0700
Subject: Delaying an interrupt handler
Message-ID: <20150323121844.GA4484@debian>
To: kernelnewbies@lists.kernelnewbies.org
List-Id: kernelnewbies.lists.kernelnewbies.org

Hi.
It is known that no semaphore synchronization should be
used inside an interrupt handler.

Anyway, I am looking at a freeBSD device driver (written by
a profesionist) and there are semaphores inside an interrupt
handler's subroutine.

Since I should port to linux that driver, I ask you how can I
reach such synchronization under linux; I tried to use semaphores
inside my handler but I got complains, and I don't want to break
the law, so no semaphores for me.

The scenario is the following:

firmware downloader {

while(fw_blocks--){

/* the call below will cause an interrupt */
load_block();

/* sleep unitl the int handler ackn's the previous
operation, and prevent ANY int. handler operations
until the process goes actually to sleep through the
following call */

sleep();      }
	  }


int handler {

if(the process is NOT asleep)
	wait();

wake up the process.
			}


NOTE: I am on a 2.6.10 in order to be closely tutored by LDD3.