Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756190Ab1DKWGK (ORCPT ); Mon, 11 Apr 2011 18:06:10 -0400 Received: from smtp-out.google.com ([74.125.121.67]:28449 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756089Ab1DKWGJ (ORCPT ); Mon, 11 Apr 2011 18:06:09 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=from:to:cc:subject:date:message-id:x-mailer; b=m4fBblOHD7JGw+ZLxilTPUEEMn8N066ueK7NfqYSLPsxStNeR/Y47yBfRH1ghXdSs F9Y/T5Hxl3JfpoBYLnZcw== From: Nat Gurumoorthy To: Jean Delvare , Guenter Roeck , Wim Van Sebroeck Cc: Mike Waychison , lm-sensors@lm-sensors.org, linux-kernel@vger.kernel.org, linux-watchdog@vger.kernel.org, Nat Gurumoorthy Subject: [PATCH v3 0/2] Make all it87 drivers SMP safe Date: Mon, 11 Apr 2011 15:05:22 -0700 Message-Id: <1302559522-18899-1-git-send-email-natg@google.com> X-Mailer: git-send-email 1.7.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1532 Lines: 37 There are 3 different drivers that touch the it87 hardware registers. The 3 drivers have been written independently and access the it87 hardware registers assuming they are the only driver accessing it. This change attempts to serialize access to the hardware by using "request_muxed_region" macro defined by Alan Cox. Call to this macro will hold off the requestor if the resource is currently busy. The use of the above macro makes it possible to get rid of spinlocks in it8712f_wdt.c and it87_wdt.c watchdog drivers. This also greatly simplifies the implementation of it87_wdt.c driver. 01 - Changes to it87 watchdog driver to use "request_muxed_region" drivers/watchdog/it8712f_wdt.c drivers/watchdog/it87_wdt.c 02 - Chages to hwmon it87 driver to use "request_muxed_region" drivers/hwmon/it87.c drivers/hwmon/it87.c | 4 ++++ drivers/watchdog/it8712f_wdt.c | 9 ++++----- drivers/watchdog/it87_wdt.c | 39 ++++----------------------------------- 3 files changed, 12 insertions(+), 40 deletions(-) Signed-off-by: Nat Gurumoorthy Patch History: v3: - Totally abandon the spinlock based approach and use "request_muxed_region" to hold off requestors if the resource is busy. v2: - More verbose patch headers. Add In-Reply-To: field. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/