On Tue, Jul 28, 2015 at 09:42:27AM +0800, Zhang Rui wrote: > From 57edba9c677e47354846db951014dc4d5b13ce54 Mon Sep 17 00:00:00 2001 > From: Zhang Rui <rui.zhang@xxxxxxxxx> > Date: Sun, 26 Jul 2015 14:15:36 +0800 > Subject: [PATCH] PCI: Disable async suspend/resume for Jmicron chip > > In https://bugzilla.kernel.org/show_bug.cgi?id=81551, > we found that Jmicron chip 361/363 is broken after resume if async noirq > (76569faa62 (PM / sleep: Asynchronous threads for resume_noirq)) is supported, > thus commit e6b7e41cdd (ata: Disabling the async PM for JMicron chip 363/361) > is introduced to fix this problem. > But then, we found that Jmicron chip 368 also has this problem, and it is decided > to disable the pm async feature for all the Jmicron chips. > > But how to fix this was discussed in the mailing list for some time. > After some investigation, we believe that a proper fix is to disable > the async PM in PCI instead of ata driver, because, on this platform, > pci_resume_noirq() of IDE controller must happen after pci_resume_noirq() > of AHCI controller. But as .resume_noirq() of the pata_jmicron driver is > no-op, this suggests that it is the PCI common actions, aka, > pci_pm_default_resume_early(), have the dependency. > To fix this, using device_pm_wait_for_dev() in pata_jmicron driver can not > solve the dependency because pci_pm_default_resume_early() is invoked before > driver callback being invoked, plus, as it is the PCI common actions that > have the dependency, it is reasonable to fix it in PCI bus code, > rather than driver code. > > This patch is made based on the patch from Liu Chuansheng at > https://lkml.org/lkml/2014/12/5/74 > it reverts commit e6b7e41cdd ("ata: Disabling the async PM for JMicron > chip 363/361"), and introduces a PCI quirk to disable async PM for Jmicron > chips. > > Reference: https://bugzilla.kernel.org/show_bug.cgi?id=81551 > Tested-by: Jay <MyMailClone@xxxxxxxxxxx> > Tested-by: Barto <mister.freeman@xxxxxxxxxxx> > Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> Acked-by: Tejun Heo <tj@xxxxxxxxxx> > /* > + * For JMicron chips, we need to disable the async_suspend method, otherwise > + * they will hit the power-on issue when doing device resume, add one quick > + * solution to disable the async_suspend method. > + */ Maybe add a link to the bug report and/or discussion thread? Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
