xref: /linux/Documentation/driver-api/firmware/lookup-order.rst (revision bd628c1bed7902ec1f24ba0fe70758949146abbe)
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2Firmware lookup order
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4
5Different functionality is available to enable firmware to be found.
6Below is chronological order of how firmware will be looked for once
7a driver issues a firmware API call.
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9* The ''Built-in firmware'' is checked first, if the firmware is present we
10  return it immediately
11* The ''Firmware cache'' is looked at next. If the firmware is found we
12  return it immediately
13* The ''Direct filesystem lookup'' is performed next, if found we
14  return it immediately
15* If no firmware has been found and the fallback mechanism was enabled
16  the sysfs interface is created. After this either a kobject uevent
17  is issued or the custom firmware loading is relied upon for firmware
18  loading up to the timeout value.
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