From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Walmsley Subject: Re: [PATCH 04/11] ARM: OMAP2+: usb_host_fs: add custom reset for usb_host_fs (fsusb) Date: Thu, 7 Jun 2012 04:52:50 -0600 (MDT) Message-ID: References: <20120607060901.25532.68354.stgit@dusk> <20120607061308.25532.19767.stgit@dusk> <20120607073112.GX12766@atomide.com> <20120607075158.GZ12766@atomide.com> <20120607075541.GF16342@arwen.pp.htv.fi> <4FD0602B.9070704@ti.com> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: Received: from utopia.booyaka.com ([72.9.107.138]:45793 "EHLO utopia.booyaka.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756657Ab2FGKwv (ORCPT ); Thu, 7 Jun 2012 06:52:51 -0400 In-Reply-To: <4FD0602B.9070704@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: "Cousson, Benoit" Cc: balbi@ti.com, Tony Lindgren , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Tero Kristo On Thu, 7 Jun 2012, Cousson, Benoit wrote: > In fact we should delay the reset to the very last moment and > potentially reset the IPs not under driver control later after a couple > of second for example. It will avoid reseting every IP that will be > handled properly by drivers. We discussed this a couple of years ago on the list and aligned on late and lazy resets, from my recollection. The main reason why it wasn't implemented was because there were some drivers that were not yet PM runtime-converted. This would have caused crashes, since the core code would have no idea that the non-PM-runtime drivers had initialized their devices, and so the core just went ahead and reset those anyway. It might actually be safe now to switch to the late reset arrangement, depending on whether the rest of the drivers have been PM runtime-converted by now. Of course, it would all be moot if the reset is moved away from the hwmod code into the drivers. - Paul From mboxrd@z Thu Jan 1 00:00:00 1970 From: paul@pwsan.com (Paul Walmsley) Date: Thu, 7 Jun 2012 04:52:50 -0600 (MDT) Subject: [PATCH 04/11] ARM: OMAP2+: usb_host_fs: add custom reset for usb_host_fs (fsusb) In-Reply-To: <4FD0602B.9070704@ti.com> References: <20120607060901.25532.68354.stgit@dusk> <20120607061308.25532.19767.stgit@dusk> <20120607073112.GX12766@atomide.com> <20120607075158.GZ12766@atomide.com> <20120607075541.GF16342@arwen.pp.htv.fi> <4FD0602B.9070704@ti.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, 7 Jun 2012, Cousson, Benoit wrote: > In fact we should delay the reset to the very last moment and > potentially reset the IPs not under driver control later after a couple > of second for example. It will avoid reseting every IP that will be > handled properly by drivers. We discussed this a couple of years ago on the list and aligned on late and lazy resets, from my recollection. The main reason why it wasn't implemented was because there were some drivers that were not yet PM runtime-converted. This would have caused crashes, since the core code would have no idea that the non-PM-runtime drivers had initialized their devices, and so the core just went ahead and reset those anyway. It might actually be safe now to switch to the late reset arrangement, depending on whether the rest of the drivers have been PM runtime-converted by now. Of course, it would all be moot if the reset is moved away from the hwmod code into the drivers. - Paul