From: Alan Stern Date: Thu, 29 Jan 2015 20:05:04 +0000 (-0500) Subject: USB: add flag for HCDs that can't receive wakeup requests (isp1760-hcd) X-Git-Tag: v3.18.9~44 X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4e5b83d8e80254b1ad0831e4ce1bcb64fbfd830c;p=linux USB: add flag for HCDs that can't receive wakeup requests (isp1760-hcd) commit 074f9dd55f9cab1b82690ed7e44bcf38b9616ce0 upstream. Currently the USB stack assumes that all host controller drivers are capable of receiving wakeup requests from downstream devices. However, this isn't true for the isp1760-hcd driver, which means that it isn't safe to do a runtime suspend of any device attached to a root-hub port if the device requires wakeup. This patch adds a "cant_recv_wakeups" flag to the usb_hcd structure and sets the flag in isp1760-hcd. The core is modified to prevent a direct child of the root hub from being put into runtime suspend with wakeup enabled if the flag is set. Signed-off-by: Alan Stern Tested-by: Nicolas Pitre Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 900264a5baab..d7a6d8bc510b 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -1784,6 +1784,18 @@ static int autosuspend_check(struct usb_device *udev) dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n"); return -EOPNOTSUPP; } + + /* + * If the device is a direct child of the root hub and the HCD + * doesn't handle wakeup requests, don't allow autosuspend when + * wakeup is needed. + */ + if (w && udev->parent == udev->bus->root_hub && + bus_to_hcd(udev->bus)->cant_recv_wakeups) { + dev_dbg(&udev->dev, "HCD doesn't handle wakeup requests\n"); + return -EOPNOTSUPP; + } + udev->do_remote_wakeup = w; return 0; } diff --git a/drivers/usb/host/isp1760-hcd.c b/drivers/usb/host/isp1760-hcd.c index e752c3098f38..d2a856528471 100644 --- a/drivers/usb/host/isp1760-hcd.c +++ b/drivers/usb/host/isp1760-hcd.c @@ -2247,6 +2247,9 @@ struct usb_hcd *isp1760_register(phys_addr_t res_start, resource_size_t res_len, hcd->rsrc_start = res_start; hcd->rsrc_len = res_len; + /* This driver doesn't support wakeup requests */ + hcd->cant_recv_wakeups = 1; + ret = usb_add_hcd(hcd, irq, irqflags); if (ret) goto err_unmap; diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h index 9e8d161bf2db..2f48e1756cbd 100644 --- a/include/linux/usb/hcd.h +++ b/include/linux/usb/hcd.h @@ -146,6 +146,8 @@ struct usb_hcd { unsigned amd_resume_bug:1; /* AMD remote wakeup quirk */ unsigned can_do_streams:1; /* HC supports streams */ unsigned tpl_support:1; /* OTG & EH TPL support */ + unsigned cant_recv_wakeups:1; + /* wakeup requests from downstream aren't received */ unsigned int irq; /* irq allocated */ void __iomem *regs; /* device memory/io */