From: Hans Verkuil <[email protected]> During the 2012 Media Workshop it was decided that bus_info as returned by VIDIOC_QUERYCAP can no longer be empty. It should be a unique identifier, and empty strings are obviously not unique.
Signed-off-by: Hans Verkuil <[email protected]> --- Documentation/DocBook/media/v4l/vidioc-querycap.xml | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/Documentation/DocBook/media/v4l/vidioc-querycap.xml b/Documentation/DocBook/media/v4l/vidioc-querycap.xml index f33dd74..e3df17a 100644 --- a/Documentation/DocBook/media/v4l/vidioc-querycap.xml +++ b/Documentation/DocBook/media/v4l/vidioc-querycap.xml @@ -90,11 +90,16 @@ ambiguities.</entry> <entry>__u8</entry> <entry><structfield>bus_info</structfield>[32]</entry> <entry>Location of the device in the system, a -NUL-terminated ASCII string. For example: "PCI Slot 4". This +NUL-terminated ASCII string. For example: "PCI:0000:05:06.0". This information is intended for users, to distinguish multiple -identical devices. If no such information is available the field may -simply count the devices controlled by the driver, or contain the -empty string (<structfield>bus_info</structfield>[0] = 0).<!-- XXX pci_dev->slot_name example --></entry> +identical devices. If no such information is available the field must +simply count the devices controlled by the driver ("vivi-000"). The bus_info +must start with "PCI:" for PCI boards, "PCIe:" for PCI Express boards, +"usb-" for USB devices, "I2C:" for i2c devices and "ISA:" for ISA devices. +For devices without a bus it should start with the driver name, optionally +followed by "-" and an index if multiple instances of the device as possible. +Many platform devices can have only one instance, so in that case bus_info +is identical to the <structfield>driver</structfield> field.</entry> </row> <row> <entry>__u32</entry> -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
