Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759425AbYAFWoq (ORCPT ); Sun, 6 Jan 2008 17:44:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759155AbYAFWod (ORCPT ); Sun, 6 Jan 2008 17:44:33 -0500 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:42418 "EHLO amd.ucw.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1758506AbYAFWoa (ORCPT ); Sun, 6 Jan 2008 17:44:30 -0500 Date: Sun, 6 Jan 2008 23:44:29 +0100 From: Pavel Machek To: Alan Stern Cc: Oliver Neukum , Raymano Garibaldi , Andrew Morton , Denys Vlasenko , Kernel development list , USB development list Subject: Re: [linux-usb-devel] [FEATURE REQUEST] Transparent hot plugging of root file system on portable storage devices. Message-ID: <20080106224429.GA1664@elf.ucw.cz> References: <200801062159.46481.oliver@neukum.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3103 Lines: 105 On Sun 2008-01-06 17:26:17, Alan Stern wrote: > On Sun, 6 Jan 2008, Oliver Neukum wrote: > > > Am Sonntag 06 Januar 2008 schrieb Alan Stern: > > > What about people who want to suspend to RAM instead of hibernating and > > > _do_ want to unplug the USB device containing their root filesystem > > > while the machine is asleep? Ok, I guess I'm lost here. That sounds like a nice way to do self-leg-shooting. Are there such people? > > > ?In this case we will _know_ that the > > > power session has been interrupted, but USB Persist won't activate > > > because the host controller never lost power. > > > > Would it be hard to force the persist feature on for a replugged device? > > Right now the persist feature is enabled by a per-device boolean flag. > In theory the flag could accept 3 values: off, on if power was lost, > or on for any resume transition. This would not be a hard change. But do we need it? Did you progress on "usb-storage-autosuspend"? Here are my hacks to try to get SATA to survive autosuspend; unfortunately they do not work :-(. Pavel diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index 54f38c2..21e6709 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -1808,8 +1808,22 @@ static void ahci_thaw(struct ata_port *a writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK); } +struct pci_dev *my_pdev; + static void ahci_error_handler(struct ata_port *ap) { + struct ata_host *host = ap->host; + int rc; + extern int slept; + + if (slept) { + printk("ahci_error_handler: Resuming...\n"); + rc =ahci_pci_device_resume(my_pdev); + printk("ahci: bad %d\n", rc); + + printk("ahci_error_handler: Device resumed?\n"); + } + if (!(ap->pflags & ATA_PFLAG_FROZEN)) { /* restart engine */ ahci_stop_engine(ap); @@ -1945,7 +1959,7 @@ static int ahci_pci_device_resume(struct if (rc) return rc; - if (pdev->dev.power.power_state.event == PM_EVENT_SUSPEND) { + if (1) { rc = ahci_reset_controller(host); if (rc) return rc; @@ -2179,6 +2193,7 @@ static void ahci_p5wdh_workaround(struct } } + static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) { static int printed_version; @@ -2190,6 +2205,7 @@ static int ahci_init_one(struct pci_dev int i, rc; VPRINTK("ENTER\n"); + my_pdev = pdev; WARN_ON(ATA_MAX_QUEUE > AHCI_MAX_CMDS); @@ -2283,8 +2299,11 @@ static int ahci_init_one(struct pci_dev ahci_print_info(host); pci_set_master(pdev); - return ata_host_activate(host, pdev->irq, ahci_interrupt, IRQF_SHARED, + + rc = ata_host_activate(host, pdev->irq, ahci_interrupt, IRQF_SHARED, &ahci_sht); + pci_save_state(pdev); + return rc; } static int __init ahci_init(void) -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- 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/