In /logs/firmware/unblob_extracted/firmware_extract/11108416-13869836.lzma_extract/lzma.uncompressed_extract/3761304-11775640.cpio_portable_ascii_extract/usr/bin/led_blink.sh line 6:

echo ${GPIO_NUM} > /sys/class/gpio/export

     ^---------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 

echo "${GPIO_NUM}" > /sys/class/gpio/export

In /logs/firmware/unblob_extracted/firmware_extract/11108416-13869836.lzma_extract/lzma.uncompressed_extract/3761304-11775640.cpio_portable_ascii_extract/usr/bin/led_blink.sh line 7:

echo out > /sys/class/gpio/gpio${GPIO_NUM}/direction

                               ^---------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 

echo out > /sys/class/gpio/gpio"${GPIO_NUM}"/direction

In /logs/firmware/unblob_extracted/firmware_extract/11108416-13869836.lzma_extract/lzma.uncompressed_extract/3761304-11775640.cpio_portable_ascii_extract/usr/bin/led_blink.sh line 8:

echo ${GPIO_NUM} > /sys/class/gpio/gpio${GPIO_NUM}/value

     ^---------^ SC2086 (info): Double quote to prevent globbing and word splitting.

                                       ^---------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 

echo "${GPIO_NUM}" > /sys/class/gpio/gpio"${GPIO_NUM}"/value

In /logs/firmware/unblob_extracted/firmware_extract/11108416-13869836.lzma_extract/lzma.uncompressed_extract/3761304-11775640.cpio_portable_ascii_extract/usr/bin/led_blink.sh line 10:

while [ 1 ]; do

        ^-- SC2161 (style): Instead of '[ 1 ]', use 'true'.

In /logs/firmware/unblob_extracted/firmware_extract/11108416-13869836.lzma_extract/lzma.uncompressed_extract/3761304-11775640.cpio_portable_ascii_extract/usr/bin/led_blink.sh line 12:

    for i in `seq 0 3`; do

    ^-^ SC2034 (warning): i appears unused. Verify use (or export if used externally).

             ^-------^ SC2006 (style): Use $(...) notation instead of legacy backticks `...`.

Did you mean: 

    for i in $(seq 0 3); do

In /logs/firmware/unblob_extracted/firmware_extract/11108416-13869836.lzma_extract/lzma.uncompressed_extract/3761304-11775640.cpio_portable_ascii_extract/usr/bin/led_blink.sh line 13:

        echo 1 > /sys/class/gpio/gpio${GPIO_NUM}/value

                                     ^---------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 

        echo 1 > /sys/class/gpio/gpio"${GPIO_NUM}"/value

In /logs/firmware/unblob_extracted/firmware_extract/11108416-13869836.lzma_extract/lzma.uncompressed_extract/3761304-11775640.cpio_portable_ascii_extract/usr/bin/led_blink.sh line 15:

        echo 0 > /sys/class/gpio/gpio${GPIO_NUM}/value

                                     ^---------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 

        echo 0 > /sys/class/gpio/gpio"${GPIO_NUM}"/value

In /logs/firmware/unblob_extracted/firmware_extract/11108416-13869836.lzma_extract/lzma.uncompressed_extract/3761304-11775640.cpio_portable_ascii_extract/usr/bin/led_blink.sh line 23:

echo ${GPIO_NUM} > /sys/class/gpio/unexport

     ^---------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 

echo "${GPIO_NUM}" > /sys/class/gpio/unexport

For more information:

  https://www.shellcheck.net/wiki/SC2034 -- i appears unused. Verify use (or ...

  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...

  https://www.shellcheck.net/wiki/SC2006 -- Use $(...) notation instead of le...