Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759179Ab3GZSo2 (ORCPT ); Fri, 26 Jul 2013 14:44:28 -0400 Received: from us02smtp2.synopsys.com ([198.182.60.77]:42097 "EHLO alvesta.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751183Ab3GZSoZ convert rfc822-to-8bit (ORCPT ); Fri, 26 Jul 2013 14:44:25 -0400 From: Paul Zimmerman To: "balbi@ti.com" , "Ivan T. Ivanov" CC: "gregkh@linuxfoundation.org" , "linux-usb@vger.kernel.org" , "linux-omap@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: RE: [PATCH] usb: dwc3: core: modify IO memory resource after deferred probe completes Thread-Topic: [PATCH] usb: dwc3: core: modify IO memory resource after deferred probe completes Thread-Index: AQHOiVPvkmnt8PfOUEep6UDMuSIK7Jl1y1AggACJGwD//92QsIAAyPcAgAAzyoCAABfxUA== Date: Fri, 26 Jul 2013 18:44:23 +0000 Message-ID: References: <1374769590-14491-1-git-send-email-iivanov@mm-sol.com> <20130725205224.GA12209@radagast> <1374821306.1956.34.camel@iivanov-dev.int.mm-sol.com> <20130726095347.GA2970@radagast> In-Reply-To: <20130726095347.GA2970@radagast> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.9.64.241] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1500 Lines: 34 > From: Felipe Balbi [mailto:balbi@ti.com] > Sent: Friday, July 26, 2013 2:54 AM > > > > Also, this is not *modifying* what was passed, just skipping the xHCI > > > > address space so we don't request_mem_region() an area we won't really > > > > handle and prevent xhci-hcd.ko from probing. > > > > > > Hmm? platform_get_resource() returns a pointer to an entry in the > > > platform_device's resource[] array. And "res->start +=" modifies the > > > entry pointed at. If it didn't, the bug fixed by this patch wouldn't > > > have happened. > > > > > > Are you sure this code will work OK if you build the driver as a module, > > > modprobe it, rmmod it, and then modprobe it again? Seems like it won't, > > > unless the dev->resource[] array gets reinitialized in between somehow. > > gotta try that one... Perhaps the correct way would be to copy the > resource to a private struct resource and modify that one, leaving > pdev->resources untouched. Maybe this is a dumb question, but why can't the driver that is going to use the resource after this just "know" that it has to add DWC3_GLOBALS_REGS_START to the start address? Are there some versions of the core where that is not the case? Or, maybe there should be two sets of resources? -- Paul -- 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/