FASTBOOT_DEVICE_SPECIFIER is empty if clients are not enumerated in time

[jesperbnp]

Sorry for spamming issues, but I'm trying to set up a production line using rpi-sb-provisioner and seem to be running into multiple issues :-)

FASTBOOT_DEVICE_SPECIFIER sometimes returns empty from this line. Especially when multiple USB devices has to be enumerated at the same time:

rpi-sb-provisioner/service/rpi-sb-provisioner.sh

Line 938 in 170825a

FASTBOOT_DEVICE_SPECIFIER="$(fastboot devices | grep "${TARGET_DEVICE_SERIAL}" | cut -f1)"

I added a crude retry/timeout loop which repeats until the device is detected:

echo "Looking for $TARGET_DEVICE_SERIAL" >&2
FASTBOOT_DEVICE_SPECIFIER=""
TIMEOUT=0
set +e
while [ -z "$FASTBOOT_DEVICE_SPECIFIER" ]; do
  sleep 1
  FASTBOOT_DEVICE_SPECIFIER="$(timeout 5 fastboot devices | grep "${TARGET_DEVICE_SERIAL}" | cut -f1)"
  echo "$TIMEOUT Found device: $FASTBOOT_DEVICE_SPECIFIER" >&2
  TIMEOUT=$(( TIMEOUT + 1 ))
  if [ "$TIMEOUT" -ge 30 ]; then
    break
  fi
done
echo "Found device specifier: $FASTBOOT_DEVICE_SPECIFIER" >&2
set -e

With above retry mechanism I finally got it working. As can be seenn the devices are finally enumerated about 10 seconds after hitting the code:

Mar 08 22:40:08 nnsecure bash[94691]: Looking for 6c9bc4e3
Mar 08 22:40:09 nnsecure bash[94691]: 0 Found device:
Mar 08 22:40:11 nnsecure bash[94691]: 1 Found device:
Mar 08 22:40:12 nnsecure bash[94691]: 2 Found device:
Mar 08 22:40:13 nnsecure bash[94691]: 3 Found device:
Mar 08 22:40:14 nnsecure bash[94691]: 4 Found device:
Mar 08 22:40:16 nnsecure bash[94691]: 5 Found device:
Mar 08 22:40:16 nnsecure kernel: usb 1-1.2: new high-speed USB device number 49 using xhci-hcd
Mar 08 22:40:17 nnsecure kernel: usb 1-1.2: device descriptor read/64, error -71
Mar 08 22:40:18 nnsecure kernel: usb 1-1.2: New USB device found, idVendor=18d1, idProduct=4e40, bcdDevice= 1.00
Mar 08 22:40:18 nnsecure kernel: usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Mar 08 22:40:18 nnsecure kernel: usb 1-1.2: Product: Raspberry Pi Compute Module 4 Rev 1.1
Mar 08 22:40:18 nnsecure kernel: usb 1-1.2: Manufacturer: Raspberry Pi
Mar 08 22:40:18 nnsecure kernel: usb 1-1.2: SerialNumber: 100000006c9bc4e3
Mar 08 22:40:18 nnsecure mtp-probe[103075]: checking bus 1, device 49: "/sys/devices/platform/axi/1000120000.pcie/1f00200000.usb/xhci-hcd.0/usb1/1-1/1-1.2"
Mar 08 22:40:18 nnsecure mtp-probe[103075]: bus: 1, device: 49 was not an MTP device
Mar 08 22:40:18 nnsecure mtp-probe[103076]: checking bus 1, device 49: "/sys/devices/platform/axi/1000120000.pcie/1f00200000.usb/xhci-hcd.0/usb1/1-1/1-1.2"
Mar 08 22:40:18 nnsecure mtp-probe[103076]: bus: 1, device: 49 was not an MTP device
Mar 08 22:40:18 nnsecure bash[94691]: 6 Found device:
Mar 08 22:40:19 nnsecure bash[94691]: 7 Found device: 100000006c9bc4e3
Mar 08 22:40:19 nnsecure bash[94691]: Found device specifier: 100000006c9bc4e3