diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-usb | 16 | ||||
| -rw-r--r-- | Documentation/usb/power-management.txt | 11 | ||||
| -rw-r--r-- | drivers/usb/core/hub.c | 39 | ||||
| -rw-r--r-- | drivers/usb/core/sysfs.c | 31 | ||||
| -rw-r--r-- | include/linux/usb.h | 4 |
5 files changed, 75 insertions, 26 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb index 3a4abfc44f5e..136ba17d2da0 100644 --- a/Documentation/ABI/testing/sysfs-bus-usb +++ b/Documentation/ABI/testing/sysfs-bus-usb @@ -134,19 +134,21 @@ Description: enabled for the device. Developer can write y/Y/1 or n/N/0 to the file to enable/disable the feature. -What: /sys/bus/usb/devices/.../power/usb3_hardware_lpm -Date: June 2015 +What: /sys/bus/usb/devices/.../power/usb3_hardware_lpm_u1 + /sys/bus/usb/devices/.../power/usb3_hardware_lpm_u2 +Date: November 2015 Contact: Kevin Strasser <kevin.strasser@linux.intel.com> + Lu Baolu <baolu.lu@linux.intel.com> Description: If CONFIG_PM is set and a USB 3.0 lpm-capable device is plugged in to a xHCI host which supports link PM, it will check if U1 and U2 exit latencies have been set in the BOS descriptor; if - the check is is passed and the host supports USB3 hardware LPM, + the check is passed and the host supports USB3 hardware LPM, USB3 hardware LPM will be enabled for the device and the USB - device directory will contain a file named - power/usb3_hardware_lpm. The file holds a string value (enable - or disable) indicating whether or not USB3 hardware LPM is - enabled for the device. + device directory will contain two files named + power/usb3_hardware_lpm_u1 and power/usb3_hardware_lpm_u2. These + files hold a string value (enable or disable) indicating whether + or not USB3 hardware LPM U1 or U2 is enabled for the device. What: /sys/bus/usb/devices/.../removable Date: February 2012 diff --git a/Documentation/usb/power-management.txt b/Documentation/usb/power-management.txt index 4a15c90bc11d..0a94ffe17ab6 100644 --- a/Documentation/usb/power-management.txt +++ b/Documentation/usb/power-management.txt @@ -537,17 +537,18 @@ relevant attribute files are usb2_hardware_lpm and usb3_hardware_lpm. can write y/Y/1 or n/N/0 to the file to enable/disable USB2 hardware LPM manually. This is for test purpose mainly. - power/usb3_hardware_lpm + power/usb3_hardware_lpm_u1 + power/usb3_hardware_lpm_u2 When a USB 3.0 lpm-capable device is plugged in to a xHCI host which supports link PM, it will check if U1 and U2 exit latencies have been set in the BOS descriptor; if the check is is passed and the host supports USB3 hardware LPM, USB3 hardware LPM will be - enabled for the device and this file will be created. - The file holds a string value (enable or disable) - indicating whether or not USB3 hardware LPM is - enabled for the device. + enabled for the device and these files will be created. + The files hold a string value (enable or disable) + indicating whether or not USB3 hardware LPM U1 or U2 + is enabled for the device. USB Port Power Control ---------------------- diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index ddbf32d599cb..8683436788c3 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3895,17 +3895,30 @@ static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev, return; } - if (usb_set_lpm_timeout(udev, state, timeout)) + if (usb_set_lpm_timeout(udev, state, timeout)) { /* If we can't set the parent hub U1/U2 timeout, * device-initiated LPM won't be allowed either, so let the xHCI * host know that this link state won't be enabled. */ hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state); + } else { + /* Only a configured device will accept the Set Feature + * U1/U2_ENABLE + */ + if (udev->actconfig) + usb_set_device_initiated_lpm(udev, state, true); - /* Only a configured device will accept the Set Feature U1/U2_ENABLE */ - else if (udev->actconfig) - usb_set_device_initiated_lpm(udev, state, true); - + /* As soon as usb_set_lpm_timeout(timeout) returns 0, the + * hub-initiated LPM is enabled. Thus, LPM is enabled no + * matter the result of usb_set_device_initiated_lpm(). + * The only difference is whether device is able to initiate + * LPM. + */ + if (state == USB3_LPM_U1) + udev->usb3_lpm_u1_enabled = 1; + else if (state == USB3_LPM_U2) + udev->usb3_lpm_u2_enabled = 1; + } } /* @@ -3945,6 +3958,18 @@ static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev, dev_warn(&udev->dev, "Could not disable xHCI %s timeout, " "bus schedule bandwidth may be impacted.\n", usb3_lpm_names[state]); + + /* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM + * is disabled. Hub will disallows link to enter U1/U2 as well, + * even device is initiating LPM. Hence LPM is disabled if hub LPM + * timeout set to 0, no matter device-initiated LPM is disabled or + * not. + */ + if (state == USB3_LPM_U1) + udev->usb3_lpm_u1_enabled = 0; + else if (state == USB3_LPM_U2) + udev->usb3_lpm_u2_enabled = 0; + return 0; } @@ -3979,8 +4004,6 @@ int usb_disable_lpm(struct usb_device *udev) if (usb_disable_link_state(hcd, udev, USB3_LPM_U2)) goto enable_lpm; - udev->usb3_lpm_enabled = 0; - return 0; enable_lpm: @@ -4038,8 +4061,6 @@ void usb_enable_lpm(struct usb_device *udev) usb_enable_link_state(hcd, udev, USB3_LPM_U1); usb_enable_link_state(hcd, udev, USB3_LPM_U2); - - udev->usb3_lpm_enabled = 1; } EXPORT_SYMBOL_GPL(usb_enable_lpm); diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c index d9ec2de6c4cf..65b6e6b84043 100644 --- a/drivers/usb/core/sysfs.c +++ b/drivers/usb/core/sysfs.c @@ -531,7 +531,7 @@ static ssize_t usb2_lpm_besl_store(struct device *dev, } static DEVICE_ATTR_RW(usb2_lpm_besl); -static ssize_t usb3_hardware_lpm_show(struct device *dev, +static ssize_t usb3_hardware_lpm_u1_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_device *udev = to_usb_device(dev); @@ -539,7 +539,7 @@ static ssize_t usb3_hardware_lpm_show(struct device *dev, usb_lock_device(udev); - if (udev->usb3_lpm_enabled) + if (udev->usb3_lpm_u1_enabled) p = "enabled"; else p = "disabled"; @@ -548,7 +548,26 @@ static ssize_t usb3_hardware_lpm_show(struct device *dev, return sprintf(buf, "%s\n", p); } -static DEVICE_ATTR_RO(usb3_hardware_lpm); +static DEVICE_ATTR_RO(usb3_hardware_lpm_u1); + +static ssize_t usb3_hardware_lpm_u2_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct usb_device *udev = to_usb_device(dev); + const char *p; + + usb_lock_device(udev); + + if (udev->usb3_lpm_u2_enabled) + p = "enabled"; + else + p = "disabled"; + + usb_unlock_device(udev); + + return sprintf(buf, "%s\n", p); +} +static DEVICE_ATTR_RO(usb3_hardware_lpm_u2); static struct attribute *usb2_hardware_lpm_attr[] = { &dev_attr_usb2_hardware_lpm.attr, @@ -562,7 +581,8 @@ static struct attribute_group usb2_hardware_lpm_attr_group = { }; static struct attribute *usb3_hardware_lpm_attr[] = { - &dev_attr_usb3_hardware_lpm.attr, + &dev_attr_usb3_hardware_lpm_u1.attr, + &dev_attr_usb3_hardware_lpm_u2.attr, NULL, }; static struct attribute_group usb3_hardware_lpm_attr_group = { @@ -592,7 +612,8 @@ static int add_power_attributes(struct device *dev) if (udev->usb2_hw_lpm_capable == 1) rc = sysfs_merge_group(&dev->kobj, &usb2_hardware_lpm_attr_group); - if (udev->lpm_capable == 1) + if (udev->speed == USB_SPEED_SUPER && + udev->lpm_capable == 1) rc = sysfs_merge_group(&dev->kobj, &usb3_hardware_lpm_attr_group); } diff --git a/include/linux/usb.h b/include/linux/usb.h index b9a28074210f..b79925dd2b41 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -511,6 +511,8 @@ struct usb3_lpm_parameters { * @usb2_hw_lpm_enabled: USB2 hardware LPM is enabled * @usb2_hw_lpm_allowed: Userspace allows USB 2.0 LPM to be enabled * @usb3_lpm_enabled: USB3 hardware LPM enabled + * @usb3_lpm_u1_enabled: USB3 hardware U1 LPM enabled + * @usb3_lpm_u2_enabled: USB3 hardware U2 LPM enabled * @string_langid: language ID for strings * @product: iProduct string, if present (static) * @manufacturer: iManufacturer string, if present (static) @@ -584,6 +586,8 @@ struct usb_device { unsigned usb2_hw_lpm_enabled:1; unsigned usb2_hw_lpm_allowed:1; unsigned usb3_lpm_enabled:1; + unsigned usb3_lpm_u1_enabled:1; + unsigned usb3_lpm_u2_enabled:1; int string_langid; /* static strings from the device */ |