xref: /OK3568_Linux_fs/kernel/Documentation/driver-api/firmware/fw_search_path.rst (revision 4882a59341e53eb6f0b4789bf948001014eff981)
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2*4882a593SmuzhiyunFirmware search paths
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5*4882a593SmuzhiyunThe following search paths are used to look for firmware on your
6*4882a593Smuzhiyunroot filesystem.
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8*4882a593Smuzhiyun* fw_path_para - module parameter - default is empty so this is ignored
9*4882a593Smuzhiyun* /lib/firmware/updates/UTS_RELEASE/
10*4882a593Smuzhiyun* /lib/firmware/updates/
11*4882a593Smuzhiyun* /lib/firmware/UTS_RELEASE/
12*4882a593Smuzhiyun* /lib/firmware/
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14*4882a593SmuzhiyunThe module parameter ''path'' can be passed to the firmware_class module
15*4882a593Smuzhiyunto activate the first optional custom fw_path_para. The custom path can
16*4882a593Smuzhiyunonly be up to 256 characters long. The kernel parameter passed would be:
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18*4882a593Smuzhiyun* 'firmware_class.path=$CUSTOMIZED_PATH'
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20*4882a593SmuzhiyunThere is an alternative to customize the path at run time after bootup, you
21*4882a593Smuzhiyuncan use the file:
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23*4882a593Smuzhiyun* /sys/module/firmware_class/parameters/path
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25*4882a593SmuzhiyunYou would echo into it your custom path and firmware requested will be
26*4882a593Smuzhiyunsearched for there first.
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