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authorAlan Stern <stern@rowland.harvard.edu>2015-01-29 15:05:04 -0500
committerGreg Kroah-Hartman <greg@kroah.com>2015-01-31 09:05:06 -0800
commit074f9dd55f9cab1b82690ed7e44bcf38b9616ce0 (patch)
tree5ef4e9054a862b930cd75f394f2c0a62e14361b2 /drivers/usb/core
parent3f2cee73b650921b2e214bf487b2061a1c266504 (diff)
downloadblackbird-op-linux-074f9dd55f9cab1b82690ed7e44bcf38b9616ce0.tar.gz
blackbird-op-linux-074f9dd55f9cab1b82690ed7e44bcf38b9616ce0.zip
USB: add flag for HCDs that can't receive wakeup requests (isp1760-hcd)
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 <stern@rowland.harvard.edu> Tested-by: Nicolas Pitre <nico@linaro.org> CC: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Diffstat (limited to 'drivers/usb/core')
-rw-r--r--drivers/usb/core/driver.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index c76ec9758ce3..818369afff63 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -1780,6 +1780,18 @@ 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;
}
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