This is a note to let you know that I've just added the patch titled
USB: add flag for HCDs that can't receive wakeup requests
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-next branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will also be merged in the next major kernel release
during the merge window.
If you have any questions about this process, please let me know.
>From 074f9dd55f9cab1b82690ed7e44bcf38b9616ce0 Mon Sep 17 00:00:00 2001
From: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Date: Thu, 29 Jan 2015 15:05:04 -0500
Subject: 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@xxxxxxxxxxxxxxxxxxx>
Tested-by: Nicolas Pitre <nico@xxxxxxxxxx>
CC: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <greg@xxxxxxxxx>
---
drivers/usb/core/driver.c | 12 ++++++++++++
drivers/usb/host/isp1760-hcd.c | 3 +++
include/linux/usb/hcd.h | 2 ++
3 files changed, 17 insertions(+)
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;
}
diff --git a/drivers/usb/host/isp1760-hcd.c b/drivers/usb/host/isp1760-hcd.c
index dbba455884f4..cecf39a220e7 100644
--- a/drivers/usb/host/isp1760-hcd.c
+++ b/drivers/usb/host/isp1760-hcd.c
@@ -2245,6 +2245,9 @@ 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 8968f616e414..68b1e836dff1 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 */
--
2.2.2
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