From patchwork Thu Dec 3 08:51:44 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Martin Wilck X-Patchwork-Id: 552082 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.sourceforge.net (lists.sourceforge.net [216.34.181.88]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 673681401AF for ; Thu, 3 Dec 2015 19:52:08 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=sfs-ml-3.v29.ch3.sourceforge.com) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1a4PcQ-0000aM-QG; Thu, 03 Dec 2015 08:52:02 +0000 Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1a4PcP-0000aC-CX for tpmdd-devel@lists.sourceforge.net; Thu, 03 Dec 2015 08:52:01 +0000 Received-SPF: pass (sog-mx-4.v43.ch3.sourceforge.com: domain of ts.fujitsu.com designates 80.70.172.51 as permitted sender) client-ip=80.70.172.51; envelope-from=martin.wilck@ts.fujitsu.com; helo=dgate20.ts.fujitsu.com; Received: from dgate20.ts.fujitsu.com ([80.70.172.51]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1a4PcN-0004kP-Bg for tpmdd-devel@lists.sourceforge.net; Thu, 03 Dec 2015 08:52:01 +0000 X-SBRSScore: None Received: from unknown (HELO abgdgate60u.abg.fsc.net) ([172.25.138.90]) by dgate20u.abg.fsc.net with ESMTP; 03 Dec 2015 09:51:52 +0100 Received: from unknown (HELO pdbcooper.pdb.fsc.net) ([172.25.111.126]) by abgdgate60u.abg.fsc.net with ESMTP; 03 Dec 2015 09:51:53 +0100 Received: from pdbcooper.pdb.fsc.net (localhost [127.0.0.1]) by pdbcooper.pdb.fsc.net (8.14.9/8.14.8) with ESMTP id tB38pjBS009991; Thu, 3 Dec 2015 09:51:46 +0100 From: martin.wilck@ts.fujitsu.com To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, u.kleine-koenig@pengutronix.de Date: Thu, 3 Dec 2015 09:51:44 +0100 Message-Id: <1449132704-9952-1-git-send-email-martin.wilck@ts.fujitsu.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <20151202165338.GA18274@kroah.com> References: <20151202165338.GA18274@kroah.com> X-Spam-Score: -1.1 (-) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.5 AWL AWL: Adjusted score from AWL reputation of From: address X-Headers-End: 1a4PcN-0004kP-Bg Cc: Martin Wilck , tpmdd-devel@lists.sourceforge.net Subject: [tpmdd-devel] [PATCH v3] base/platform: fix binding for drivers without probe callback X-BeenThere: tpmdd-devel@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: Tpm Device Driver maintainance List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: tpmdd-devel-bounces@lists.sourceforge.net From: Martin Wilck Since b8b2c7d845d5, platform_drv_probe() is called for all platform devices. If drv->probe is NULL, and dev_pm_domain_attach() fails, platform_drv_probe() will return the error code from dev_pm_domain_attach(). This causes real_probe() to enter the "probe_failed" path and set dev->driver to NULL. Before b8b2c7d845d5, real_probe() would assume success if both dev->bus->probe and drv->probe were missing. As a result, a device and driver could be "bound" together just by matching their names; this doesn't work any more after b8b2c7d845d5. This change broke the assumptions of certain drivers; for example, the TPM code has long assumed that platform driver and device with matching name could be bound in this way. That assumption may cause such drivers to fail with Oops during initialization after applying this change. Failure in suspend/resume tests under qemu has also been reported. This patch restores the previous (4.3.0 and earlier) behavior of platform_drv_probe() in the case when the associated platform driver has no "probe" function. Fixes: b8b2c7d845d5 ("base/platform: assert that dev_pm_domain callbacks are called unconditionally") Signed-off-by: Martin Wilck Acked-by: Uwe Kleine-König Acked-by: Jarkko Sakkinen --- v2: fixed style issues, rephrased commit message. v3: rephrased commit message and subject again. drivers/base/platform.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 1dd6d3b..176b59f 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -513,10 +513,15 @@ static int platform_drv_probe(struct device *_dev) return ret; ret = dev_pm_domain_attach(_dev, true); - if (ret != -EPROBE_DEFER && drv->probe) { - ret = drv->probe(dev); - if (ret) - dev_pm_domain_detach(_dev, true); + if (ret != -EPROBE_DEFER) { + if (drv->probe) { + ret = drv->probe(dev); + if (ret) + dev_pm_domain_detach(_dev, true); + } else { + /* don't fail if just dev_pm_domain_attach failed */ + ret = 0; + } } if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {