Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 31 insertions, 0 deletions

diff --git a/Documentation/driver-api/firmware/fw_search_path.rst b/Documentation/driver-api/firmware/fw_search_path.rst
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+=====================
+Firmware search paths
+=====================
+
+The following search paths are used to look for firmware on your
+root filesystem.
+
+* fw_path_para - module parameter - default is empty so this is ignored
+* /lib/firmware/updates/UTS_RELEASE/
+* /lib/firmware/updates/
+* /lib/firmware/UTS_RELEASE/
+* /lib/firmware/
+
+The module parameter ''path'' can be passed to the firmware_class module
+to activate the first optional custom fw_path_para. The custom path can
+only be up to 256 characters long. The kernel parameter passed would be:
+
+* 'firmware_class.path=$CUSTOMIZED_PATH'
+
+There is an alternative to customize the path at run time after bootup, you
+can use the file:
+
+* /sys/module/firmware_class/parameters/path
+
+You would echo into it your custom path and firmware requested will be searched
+for there first. Be aware that newline characters will be taken into account
+and may not produce the intended effects. For instance you might want to use:
+
+echo -n /path/to/script > /sys/module/firmware_class/parameters/path
+
+to ensure that your script is being used.