Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752396AbbBKJTz (ORCPT ); Wed, 11 Feb 2015 04:19:55 -0500 Received: from ns.mm-sol.com ([37.157.136.199]:33900 "EHLO extserv.mm-sol.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751834AbbBKJTx (ORCPT ); Wed, 11 Feb 2015 04:19:53 -0500 Message-ID: <54DB1EAC.3060302@mm-sol.com> Date: Wed, 11 Feb 2015 11:19:40 +0200 From: Stanimir Varbanov User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: "Matwey V. Kornilov" CC: linux-kernel , Bjorn Helgaas , Greg Kroah-Hartman , Mohit KUMAR , "linux-pci@vger.kernel.org" , Viresh Kumar Subject: Re: [PATCHv2 1/2] pci: spear: Use platform_driver_probe instead of platform_driver_register References: <1423585882-5464-1-git-send-email-matwey@sai.msu.ru> <54DB0A52.4090907@mm-sol.com> In-Reply-To: Content-Type: text/plain; charset=koi8-r; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3420 Lines: 98 please don't top posting. On 02/11/2015 10:38 AM, Matwey V. Kornilov wrote: > It sounds reasonable, but does current implementation support deferring? yes, it uses deferred probe see devm_phy_get() and devm_clk_get() calls in .probe and how the returned values are checked. > Struct spear13xx_pcie_driver just dissapears from memory after init. IMO this is expected because spear13xx_pcie_driver is annotated as __initdata. The proper solution was pointed by Kumar below, but we also need to remove the __init from dw_pcie_host_init() which is called from driver .probe. > 11.02.2015 11:18 ???????????? "Stanimir Varbanov" > ???????: > >> Hi, >> >> On 02/11/2015 05:35 AM, Viresh Kumar wrote: >> >>> On 11 February 2015 at 00:31, Matwey V. Kornilov >>> wrote: >>> >>>> Use platform_driver_probe instead of platform_driver_register >>>> because the former allows us to use probe function placed into __init >>>> section >>>> and the driver itself is not support hotplugging (yet?). >>>> >>>> Signed-off-by: Matwey V. Kornilov >>>> --- >>>> Changes from v1: >>>> - Use platform_driver_probe instead of platform_driver_register to >>>> make linker happy.ven after it is used >>>> >>>> drivers/pci/host/pcie-spear13xx.c | 3 +-- >>>> 1 file changed, 1 insertion(+), 2 deletions(-) >>>> >>>> diff --git a/drivers/pci/host/pcie-spear13xx.c b/drivers/pci/host/pcie- >>>> spear13xx.c >>>> index 866465f..51e1344 100644 >>>> --- a/drivers/pci/host/pcie-spear13xx.c >>>> +++ b/drivers/pci/host/pcie-spear13xx.c >>>> @@ -371,7 +371,6 @@ static const struct of_device_id >>>> spear13xx_pcie_of_match[] = { >>>> MODULE_DEVICE_TABLE(of, spear13xx_pcie_of_match); >>>> >>>> static struct platform_driver spear13xx_pcie_driver __initdata = { >>>> - .probe = spear13xx_pcie_probe, >>>> .driver = { >>>> .name = "spear-pcie", >>>> .of_match_table = of_match_ptr(spear13xx_pcie_ >>>> of_match), >>>> @@ -382,7 +381,7 @@ static struct platform_driver spear13xx_pcie_driver >>>> __initdata = { >>>> >>>> static int __init spear13xx_pcie_init(void) >>>> { >>>> - return platform_driver_register(&spear13xx_pcie_driver); >>>> + return platform_driver_probe(&spear13xx_pcie_driver, >>>> spear13xx_pcie_probe); >>>> } >>>> module_init(spear13xx_pcie_init); >>>> >>> >>> The problem here is that the driver is never registered. And we might >>> never >>> see it in sysfs. Probably a better solution would be to just remove all >>> __init >>> parts from this driver. Let it take space even after it is used. And >>> don't care >>> about it. >>> >>> Sorry was busy in a conference and couldn't reply to your earlier mail on >>> this. >>> >> >> Using platform_driver_probe() prevents deferred probe which is problem >> because you get phy, clocks from probe, and these calls could return >> EPROBE_DEFFER. >> >> Also dw_pcie_host_init() called from spear13xx_add_pcie_port() is >> annotated as __init. I wanted send a patch which removes __init from >> dw_pcie_host_init() but I haven't time, yet. >> >> regards, >> Stan >> >> > -- 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/