diff options
| author | Matthew Garrett <mjg@redhat.com> | 2012-02-03 17:11:54 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-02-09 08:40:11 -0800 |
| commit | 0846e7e9856c0928223447d9349a877202a63f24 (patch) | |
| tree | 1ef6df58927568478e17396855c579ad45aa9fee | |
| parent | af74d2dae8f85a0e90a30594beb507f5d954fa3f (diff) | |
usb: Add support for indicating whether a port is removable
Userspace may want to make policy decisions based on whether or not a
given USB device is removable. Add a per-device member and support
for exposing it in sysfs. Information sources to populate it will be
added later.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-usb | 11 | ||||
| -rw-r--r-- | drivers/usb/core/sysfs.c | 23 | ||||
| -rw-r--r-- | include/linux/usb.h | 8 |
3 files changed, 42 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb index b4f548792e32..7c22a532fdfb 100644 --- a/Documentation/ABI/testing/sysfs-bus-usb +++ b/Documentation/ABI/testing/sysfs-bus-usb @@ -182,3 +182,14 @@ Description: USB2 hardware LPM is 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/.../removable +Date: February 2012 +Contact: Matthew Garrett <mjg@redhat.com> +Description: + Some information about whether a given USB device is + physically fixed to the platform can be inferred from a + combination of hub decriptor bits and platform-specific data + such as ACPI. This file will read either "removable" or + "fixed" if the information is available, and "unknown" + otherwise.
\ No newline at end of file diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c index 9e491ca2e5c4..566d9f94f735 100644 --- a/drivers/usb/core/sysfs.c +++ b/drivers/usb/core/sysfs.c @@ -230,6 +230,28 @@ show_urbnum(struct device *dev, struct device_attribute *attr, char *buf) } static DEVICE_ATTR(urbnum, S_IRUGO, show_urbnum, NULL); +static ssize_t +show_removable(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct usb_device *udev; + char *state; + + udev = to_usb_device(dev); + + switch (udev->removable) { + case USB_DEVICE_REMOVABLE: + state = "removable"; + break; + case USB_DEVICE_FIXED: + state = "fixed"; + break; + default: + state = "unknown"; + } + + return sprintf(buf, "%s\n", state); +} +static DEVICE_ATTR(removable, S_IRUGO, show_removable, NULL); #ifdef CONFIG_PM @@ -626,6 +648,7 @@ static struct attribute *dev_attrs[] = { &dev_attr_avoid_reset_quirk.attr, &dev_attr_authorized.attr, &dev_attr_remove.attr, + &dev_attr_removable.attr, NULL, }; static struct attribute_group dev_attr_grp = { diff --git a/include/linux/usb.h b/include/linux/usb.h index 27a4e16d2bf1..b2eb3a47caf5 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -376,6 +376,12 @@ struct usb_bus { struct usb_tt; +enum usb_device_removable { + USB_DEVICE_REMOVABLE_UNKNOWN = 0, + USB_DEVICE_REMOVABLE, + USB_DEVICE_FIXED, +}; + /** * struct usb_device - kernel's representation of a USB device * @devnum: device number; address on a USB bus @@ -432,6 +438,7 @@ struct usb_tt; * @wusb_dev: if this is a Wireless USB device, link to the WUSB * specific data for the device. * @slot_id: Slot ID assigned by xHCI + * @removable: Device can be physically removed from this port * * Notes: * Usbcore drivers should not set usbdev->state directly. Instead use @@ -509,6 +516,7 @@ struct usb_device { #endif struct wusb_dev *wusb_dev; int slot_id; + enum usb_device_removable removable; }; #define to_usb_device(d) container_of(d, struct usb_device, dev) |