From patchwork Thu Aug 22 22:01:56 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anatolij Gustschin X-Patchwork-Id: 269222 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 4DA3C2C00A9 for ; Fri, 23 Aug 2013 08:02:11 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754178Ab3HVWCA (ORCPT ); Thu, 22 Aug 2013 18:02:00 -0400 Received: from mail-out.m-online.net ([212.18.0.10]:57619 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754066Ab3HVWB7 (ORCPT ); Thu, 22 Aug 2013 18:01:59 -0400 Received: from frontend1.mail.m-online.net (frontend1.mail.intern.m-online.net [192.168.8.180]) by mail-out.m-online.net (Postfix) with ESMTP id 3cLfps10X3z3hhq4; Fri, 23 Aug 2013 00:01:57 +0200 (CEST) X-Auth-Info: 8C9siLRw0OK5jd5HLfSaoLlXdgmR8YM6SvUgV2Svoyk= Received: from localhost (p4FDE79A0.dip0.t-ipconnect.de [79.222.121.160]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA id 3cLfpr6zR3zbbpD; Fri, 23 Aug 2013 00:01:56 +0200 (CEST) From: Anatolij Gustschin To: Wolfgang Grandegger , Marc Kleine-Budde Cc: Gerhard Sittig , linux-can@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH next 1/2] net: can: mscan: add a comment on reg to idx mapping Date: Fri, 23 Aug 2013 00:01:56 +0200 Message-Id: <1377208917-16698-1-git-send-email-agust@denx.de> X-Mailer: git-send-email 1.7.9.5 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Gerhard Sittig add a comment about the magic of deriving an MSCAN component index from the peripheral's physical address / register offset Cc: linux-can@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by: Gerhard Sittig --- drivers/net/can/mscan/mpc5xxx_can.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/mscan/mpc5xxx_can.c b/drivers/net/can/mscan/mpc5xxx_can.c index 5b0ee8e..bc422ba 100644 --- a/drivers/net/can/mscan/mpc5xxx_can.c +++ b/drivers/net/can/mscan/mpc5xxx_can.c @@ -148,7 +148,10 @@ static u32 mpc512x_can_get_clock(struct platform_device *ofdev, goto exit_put; } - /* Determine the MSCAN device index from the physical address */ + /* Determine the MSCAN device index from the peripheral's + * physical address. Register address offsets against the + * IMMR base are: 0x1300, 0x1380, 0x2300, 0x2380 + */ pval = of_get_property(ofdev->dev.of_node, "reg", &plen); BUG_ON(!pval || plen < sizeof(*pval)); clockidx = (*pval & 0x80) ? 1 : 0;