diff options
Diffstat (limited to 'Documentation/usb')
-rw-r--r-- | Documentation/usb/gadget_serial.txt | 4 | ||||
-rw-r--r-- | Documentation/usb/power-management.txt | 22 | ||||
-rw-r--r-- | Documentation/usb/proc_usb_info.txt | 6 | ||||
-rw-r--r-- | Documentation/usb/usbmon.txt | 12 | ||||
-rw-r--r-- | Documentation/usb/wusb-cbaf | 9 |
5 files changed, 30 insertions, 23 deletions
diff --git a/Documentation/usb/gadget_serial.txt b/Documentation/usb/gadget_serial.txt index 9b22bd14c34..eac7df94d8e 100644 --- a/Documentation/usb/gadget_serial.txt +++ b/Documentation/usb/gadget_serial.txt @@ -114,11 +114,11 @@ modules. Then you must load the gadget serial driver. To load it as an ACM device (recommended for interoperability), do this: - modprobe g_serial use_acm=1 + modprobe g_serial To load it as a vendor specific bulk in/out device, do this: - modprobe g_serial + modprobe g_serial use_acm=0 This will also automatically load the underlying gadget peripheral controller driver. This must be done each time you reboot the gadget diff --git a/Documentation/usb/power-management.txt b/Documentation/usb/power-management.txt index e48ea1d5101..ad642615ad4 100644 --- a/Documentation/usb/power-management.txt +++ b/Documentation/usb/power-management.txt @@ -313,11 +313,13 @@ three of the methods listed above. In addition, a driver indicates that it supports autosuspend by setting the .supports_autosuspend flag in its usb_driver structure. It is then responsible for informing the USB core whenever one of its interfaces becomes busy or idle. The -driver does so by calling these three functions: +driver does so by calling these five functions: int usb_autopm_get_interface(struct usb_interface *intf); void usb_autopm_put_interface(struct usb_interface *intf); int usb_autopm_set_interface(struct usb_interface *intf); + int usb_autopm_get_interface_async(struct usb_interface *intf); + void usb_autopm_put_interface_async(struct usb_interface *intf); The functions work by maintaining a counter in the usb_interface structure. When intf->pm_usage_count is > 0 then the interface is @@ -330,10 +332,12 @@ associated with the device itself rather than any of its interfaces. This field is used only by the USB core.) The driver owns intf->pm_usage_count; it can modify the value however -and whenever it likes. A nice aspect of the usb_autopm_* routines is -that the changes they make are protected by the usb_device structure's -PM mutex (udev->pm_mutex); however drivers may change pm_usage_count -without holding the mutex. +and whenever it likes. A nice aspect of the non-async usb_autopm_* +routines is that the changes they make are protected by the usb_device +structure's PM mutex (udev->pm_mutex); however drivers may change +pm_usage_count without holding the mutex. Drivers using the async +routines are responsible for their own synchronization and mutual +exclusion. usb_autopm_get_interface() increments pm_usage_count and attempts an autoresume if the new value is > 0 and the @@ -348,6 +352,14 @@ without holding the mutex. is suspended, and it attempts an autosuspend if the value is <= 0 and the device isn't suspended. + usb_autopm_get_interface_async() and + usb_autopm_put_interface_async() do almost the same things as + their non-async counterparts. The differences are: they do + not acquire the PM mutex, and they use a workqueue to do their + jobs. As a result they can be called in an atomic context, + such as an URB's completion handler, but when they return the + device will not generally not yet be in the desired state. + There also are a couple of utility routines drivers can use: usb_autopm_enable() sets pm_usage_cnt to 0 and then calls diff --git a/Documentation/usb/proc_usb_info.txt b/Documentation/usb/proc_usb_info.txt index 077e9032d0c..fafcd472326 100644 --- a/Documentation/usb/proc_usb_info.txt +++ b/Documentation/usb/proc_usb_info.txt @@ -49,8 +49,10 @@ it and 002/048 sometime later. These files can be read as binary data. The binary data consists of first the device descriptor, then the descriptors for each -configuration of the device. That information is also shown in -text form by the /proc/bus/usb/devices file, described later. +configuration of the device. Multi-byte fields in the device and +configuration descriptors, but not other descriptors, are converted +to host endianness by the kernel. This information is also shown +in text form by the /proc/bus/usb/devices file, described later. These files may also be used to write user-level drivers for the USB devices. You would open the /proc/bus/usb/BBB/DDD file read/write, diff --git a/Documentation/usb/usbmon.txt b/Documentation/usb/usbmon.txt index 2917ce4ffdc..270481906dc 100644 --- a/Documentation/usb/usbmon.txt +++ b/Documentation/usb/usbmon.txt @@ -34,11 +34,12 @@ if usbmon is built into the kernel. Verify that bus sockets are present. # ls /sys/kernel/debug/usbmon -0s 0t 0u 1s 1t 1u 2s 2t 2u 3s 3t 3u 4s 4t 4u +0s 0u 1s 1t 1u 2s 2t 2u 3s 3t 3u 4s 4t 4u # -Now you can choose to either use the sockets numbered '0' (to capture packets on -all buses), and skip to step #3, or find the bus used by your device with step #2. +Now you can choose to either use the socket '0u' (to capture packets on all +buses), and skip to step #3, or find the bus used by your device with step #2. +This allows to filter away annoying devices that talk continuously. 2. Find which bus connects to the desired device @@ -99,8 +100,9 @@ on the event type, but there is a set of words, common for all types. Here is the list of words, from left to right: -- URB Tag. This is used to identify URBs is normally a kernel mode address - of the URB structure in hexadecimal. +- URB Tag. This is used to identify URBs, and is normally an in-kernel address + of the URB structure in hexadecimal, but can be a sequence number or any + other unique string, within reason. - Timestamp in microseconds, a decimal number. The timestamp's resolution depends on available clock, and so it can be much worse than a microsecond diff --git a/Documentation/usb/wusb-cbaf b/Documentation/usb/wusb-cbaf index 2e78b70f3ad..426ddaaef96 100644 --- a/Documentation/usb/wusb-cbaf +++ b/Documentation/usb/wusb-cbaf @@ -80,12 +80,6 @@ case $1 in start) for dev in ${2:-$hdevs} do - uwb_rc=$(readlink -f $dev/uwb_rc) - if cat $uwb_rc/beacon | grep -q -- "-1" - then - echo 13 0 > $uwb_rc/beacon - echo I: started beaconing on ch 13 on $(basename $uwb_rc) >&2 - fi echo $host_CHID > $dev/wusb_chid echo I: started host $(basename $dev) >&2 done @@ -95,9 +89,6 @@ case $1 in do echo 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > $dev/wusb_chid echo I: stopped host $(basename $dev) >&2 - uwb_rc=$(readlink -f $dev/uwb_rc) - echo -1 | cat > $uwb_rc/beacon - echo I: stopped beaconing on $(basename $uwb_rc) >&2 done ;; set-chid) |