From 23b42ce55598d9c4de8d55c7d6f0fbd4042c3c39 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Thu, 10 Dec 2015 15:27:21 -0500 Subject: [PATCH] USB: add quirk for devices with broken LPM commit ad87e03213b552a5c33d5e1e7a19a73768397010 upstream. 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 Reported-by: Steinar H. Gunderson Signed-off-by: Greg Kroah-Hartman [ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques --- drivers/usb/core/hub.c | 7 ++++++- drivers/usb/core/quirks.c | 6 ++++++ include/linux/usb/quirks.h | 3 +++ 3 files changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 882acb2a0b48e..a1e577777a02c 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -128,6 +128,10 @@ struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev) 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. */ @@ -4479,6 +4483,8 @@ 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) { @@ -4674,7 +4680,6 @@ 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 2b978ad9d9eff..0e8e656a045f6 100644 --- a/drivers/usb/core/quirks.c +++ b/drivers/usb/core/quirks.c @@ -188,6 +188,12 @@ static const struct usb_device_id usb_quirk_list[] = { /* USB3503 */ { USB_DEVICE(0x0424, 0x3503), .driver_info = USB_QUIRK_RESET_RESUME }, + /* 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 4a185a0f62426..8f4f2214652f6 100644 --- a/include/linux/usb/quirks.h +++ b/include/linux/usb/quirks.h @@ -47,4 +47,7 @@ /* device can't handle device_qualifier descriptor requests */ #define USB_QUIRK_DEVICE_QUALIFIER 0x00000100 +/* device can't handle Link Power Management */ +#define USB_QUIRK_NO_LPM BIT(10) + #endif /* __LINUX_USB_QUIRKS_H */ -- 2.47.3