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authorAlan Stern <stern@rowland.harvard.edu>2015-12-10 15:27:21 -0500
committerSasha Levin <sasha.levin@oracle.com>2016-01-22 12:24:44 -0500
commit782f17fde163a785e9bea86605aaab540f831bd8 (patch)
tree9fb306e800840290a5683b7b8f2e0b777c01c3f0
parent5163e2188b94e9141c1e8e281398c616201fd4b5 (diff)
downloadlwn-782f17fde163a785e9bea86605aaab540f831bd8.tar.gz
lwn-782f17fde163a785e9bea86605aaab540f831bd8.zip
USB: add quirk for devices with broken LPM
[ Upstream commit ad87e03213b552a5c33d5e1e7a19a73768397010 ] Some USB device / host controller combinations seem to have problems with Link Power Management. For example, Steinar found that his xHCI controller wouldn't handle bandwidth calculations correctly for two video cards simultaneously when LPM was enabled, even though the bus had plenty of bandwidth available. This patch introduces a new quirk flag for devices that should remain disabled for LPM, and creates quirk entries for Steinar's devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Steinar H. Gunderson <sgunderson@bigfoot.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
-rw-r--r--drivers/usb/core/hub.c7
-rw-r--r--drivers/usb/core/quirks.c6
-rw-r--r--include/linux/usb/quirks.h3
3 files changed, 15 insertions, 1 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 2222899c4b69..a3f3a8163fe3 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -124,6 +124,10 @@ struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
static int usb_device_supports_lpm(struct usb_device *udev)
{
+ /* Some devices have trouble with LPM */
+ if (udev->quirks & USB_QUIRK_NO_LPM)
+ return 0;
+
/* USB 2.1 (and greater) devices indicate LPM support through
* their USB 2.0 Extended Capabilities BOS descriptor.
*/
@@ -4498,6 +4502,8 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
goto fail;
}
+ usb_detect_quirks(udev);
+
if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
retval = usb_get_bos_descriptor(udev);
if (!retval) {
@@ -4692,7 +4698,6 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
if (status < 0)
goto loop;
- usb_detect_quirks(udev);
if (udev->quirks & USB_QUIRK_DELAY_INIT)
msleep(1000);
diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index 8a77a417ccfd..6b53fc3ec636 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -196,6 +196,12 @@ static const struct usb_device_id usb_quirk_list[] = {
{ USB_DEVICE(0x1a0a, 0x0200), .driver_info =
USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL },
+ /* Blackmagic Design Intensity Shuttle */
+ { USB_DEVICE(0x1edb, 0xbd3b), .driver_info = USB_QUIRK_NO_LPM },
+
+ /* Blackmagic Design UltraStudio SDI */
+ { USB_DEVICE(0x1edb, 0xbd4f), .driver_info = USB_QUIRK_NO_LPM },
+
{ } /* terminating entry must be last */
};
diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
index 9948c874e3f1..1d0043dc34e4 100644
--- a/include/linux/usb/quirks.h
+++ b/include/linux/usb/quirks.h
@@ -47,4 +47,7 @@
/* device generates spurious wakeup, ignore remote wakeup capability */
#define USB_QUIRK_IGNORE_REMOTE_WAKEUP BIT(9)
+/* device can't handle Link Power Management */
+#define USB_QUIRK_NO_LPM BIT(10)
+
#endif /* __LINUX_USB_QUIRKS_H */