From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: [PATCH 7/8] pm80xx: wait a minimum of 500ms before issuing commands to SPCv Date: Mon, 2 Nov 2015 09:00:11 +0100 Message-ID: <5637180B.3030003@suse.de> References: <1446216811-2248-1-git-send-email-brood@attotech.com> <1446216811-2248-8-git-send-email-brood@attotech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mx2.suse.de ([195.135.220.15]:55605 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751145AbbKBIAO (ORCPT ); Mon, 2 Nov 2015 03:00:14 -0500 In-Reply-To: <1446216811-2248-8-git-send-email-brood@attotech.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Benjamin Rood , linux-scsi@vger.kernel.org, xjtuwjp@gmail.com, James.Bottomley@HansenPartnership.com Cc: Benjamin Rood On 10/30/2015 03:53 PM, Benjamin Rood wrote: > The documentation for the 8070 and 8072 SPCv chip explicitly states t= hat > a minimum of 500ms must elapse before issuing commands, otherwise the > SPCv may not process them and the firmware may get into an unrecovera= ble > state requiring a reboot. While the Linux guys will probably think t= his > is 'racy', it is called out in the chip documentation and inserting t= his > delay makes power management function properly. >=20 > Signed-off-by: Benjamin Rood > --- > drivers/scsi/pm8001/pm8001_init.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) >=20 Can you please add a comment in the code, too? Just to clarify why this is done, lest that someone else tries to 'optimize' this away. Cheers, Hannes --=20 Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: J. Hawn, J. Guild, F. Imend=F6rffer, HRB 16746 (AG N=FCrnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html