• Song, Hongyan's avatar
    HID: increase maximum global item tag report size to 256 · 71f6fa90
    Song, Hongyan authored
    The maximum globale report size has changed from 32->...->96->128 in the past
    years.  With the development usage of HID, the report_size max value 128 cannot
    satisfy all requirements.
    
    There are applications need to expose intrinsic metadata to camera stabilizing
    applications such as 3DFE application. 3DFE intrinsic is designed to express
    environmental information about sensor that may dynamically change while the
    sensor is running (such data include noise spectral density, bias standard
    deviation)
    
    A sensor data field is SENSOR_VALUE_PAIR that consists of a PROPERTYKEY and
    PROPVARIANT pair. It need to report a unique PROPERTYKEY for each data field.
    
    Take “Noise Spectral Density” as an example, it report count will be
    defined as below:
    
    	"Size of Property key GUID(16 Byte) + property key index(4 Byte) +
    	size of Noise Spectral Density value(4 Byte)"
    
    In this case, the data report max is totally 192(24Byte), which is larger than
    128, while max size 128 blocked it as illegal length. So increase the report
    size to satisfy it and more demands in the future.
    Signed-off-by: default avatarSong Hongyan <hongyan.song@intel.com>
    Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
    71f6fa90
hid-core.c 56.8 KB