OnePlus 7 Pro: Update System Firmware on Custom ROM

Follow up to the OnePlus 7 Pro: LineageOS+MicroG post, where I mentioned I would have to update the Bluetooth & Modem firmware on my device. This fortunately went as smoothly as the LineageOS+MicroG install, so I’m very happy about that.

The first step was downloading the latest OxygenOS ZIP through this post: XDA Developers: [ROM][STOCK][FASTBOOT][OP7P] Stock Fastboot ROMs for OnePlus 7 Pro/ 7 Pro 5G by mauronofrio. The specific ZIP i pulled down from Android File Host was “10.0-GM21AA-OnePlus7ProOxygen_21.O.20_OTA_020_all_1909172051_db7a3f61-FASTBOOT.zip”. From there, it was just a simple matter of extracting that, images.zip, & flashing the bluetooth.img & modem.img files:

➜  Downloads cd 10.0-GM21AA-OnePlus7ProOxygen_21.O.20_OTA_020_all_1909172051_db7a3f61-FASTBOOT/images ➜  images file bluetooth.img bluetooth.img: DOS/MBR boot sector, code offset 0x3c+2, OEM-ID “MSDOS5.0”, Bytes/sector 4096, sectors/cluster 4, root entries 512, Media descriptor 0xf8, sectors/FAT 3, sectors/track 63, heads 255, sectors 16384 (volumes > 32 MB), serial number 0xbc614e, unlabeled, FAT (16 bit) ➜  images file modem.img modem.img: DOS/MBR boot sector, code offset 0x3c+2, OEM-ID “MSDOS5.0”, Bytes/sector 4096, sectors/cluster 4, root entries 512, Media descriptor 0xf8, sectors/FAT 10, sectors/track 63, heads 255, sectors 76800 (volumes > 32 MB), serial number 0xbc614e, unlabeled, FAT (16 bit)

➜  images adb devices * daemon not running; starting now at tcp:5037 * daemon started successfully List of devices attached ➜  images adb devices List of devices attached 1234abcd        device ➜  images adb reboot bootloader ➜  images fastboot devices 1234abcd        fastboot ➜  images fastboot flash bluetooth_a bluetooth.img Sending ‘bluetooth_a’ (828 KB)                     OKAY [  0.030s] Writing ‘bluetooth_a’                              OKAY [  0.005s] Finished. Total time: 0.049s ➜  images fastboot flash bluetooth_b bluetooth.img Sending ‘bluetooth_b’ (828 KB)                     OKAY [  0.032s] Writing ‘bluetooth_b’                              OKAY [  0.005s] Finished. Total time: 0.050s ➜  images fastboot flash modem_a modem.img Sending ‘modem_a’ (161700 KB)                      OKAY [  4.308s] Writing ‘modem_a’                                  OKAY [  0.633s] Finished. Total time: 4.954s ➜  images fastboot flash modem_b modem.img Sending ‘modem_b’ (161700 KB)                      OKAY [  3.769s] Writing ‘modem_b’                                  OKAY [  0.696s] Finished. Total time: 4.480s ➜  images fastboot reboot Rebooting                                          OKAY [  0.002s] Finished. Total time: 0.002s ➜  images