kernel/tools/testing/selftests/firmware/fw_userhelper.sh

   1 #!/bin/sh
   2 # This validates that the kernel will fall back to using the user helper
   3 # to load firmware it can't find on disk itself. We must request a firmware
   4 # that the kernel won't find, and any installed helper (e.g. udev) also
   5 # won't find so that we can do the load ourself manually.
   6 set -e
   7
   8 modprobe test_firmware
   9
  10 DIR=/sys/devices/virtual/misc/test_firmware
  11
  12 OLD_TIMEOUT=$(cat /sys/class/firmware/timeout)
  13
  14 FWPATH=$(mktemp -d)
  15 FW="$FWPATH/test-firmware.bin"
  16
  17 test_finish()
  18 {
  19         echo "$OLD_TIMEOUT" >/sys/class/firmware/timeout
  20         rm -f "$FW"
  21         rmdir "$FWPATH"
  22 }
  23
  24 load_fw()
  25 {
  26         local name="$1"
  27         local file="$2"
  28
  29         # This will block until our load (below) has finished.
  30         echo -n "$name" >"$DIR"/trigger_request &
  31
  32         # Give kernel a chance to react.
  33         local timeout=10
  34         while [ ! -e "$DIR"/"$name"/loading ]; do
  35                 sleep 0.1
  36                 timeout=$(( $timeout - 1 ))
  37                 if [ "$timeout" -eq 0 ]; then
  38                         echo "$0: firmware interface never appeared" >&2
  39                         exit 1
  40                 fi
  41         done
  42
  43         echo 1 >"$DIR"/"$name"/loading
  44         cat "$file" >"$DIR"/"$name"/data
  45         echo 0 >"$DIR"/"$name"/loading
  46
  47         # Wait for request to finish.
  48         wait
  49 }
  50
  51 trap "test_finish" EXIT
  52
  53 # This is an unlikely real-world firmware content. :)
  54 echo "ABCD0123" >"$FW"
  55 NAME=$(basename "$FW")
  56
  57 # Test failure when doing nothing (timeout works).
  58 echo 1 >/sys/class/firmware/timeout
  59 echo -n "$NAME" >"$DIR"/trigger_request
  60 if diff -q "$FW" /dev/test_firmware >/dev/null ; then
  61         echo "$0: firmware was not expected to match" >&2
  62         exit 1
  63 else
  64         echo "$0: timeout works"
  65 fi
  66
  67 # Put timeout high enough for us to do work but not so long that failures
  68 # slow down this test too much.
  69 echo 4 >/sys/class/firmware/timeout
  70
  71 # Load this script instead of the desired firmware.
  72 load_fw "$NAME" "$0"
  73 if diff -q "$FW" /dev/test_firmware >/dev/null ; then
  74         echo "$0: firmware was not expected to match" >&2
  75         exit 1
  76 else
  77         echo "$0: firmware comparison works"
  78 fi
  79
  80 # Do a proper load, which should work correctly.
  81 load_fw "$NAME" "$FW"
  82 if ! diff -q "$FW" /dev/test_firmware >/dev/null ; then
  83         echo "$0: firmware was not loaded" >&2
  84         exit 1
  85 else
  86         echo "$0: user helper firmware loading works"
  87 fi
  88
  89 exit 0