The nvmem cell for the MT7663 (5 GHz) radio was too small. The MT7663 EEPROM at offset 0x8000 requires the full MT7615_EEPROM_FULL_SIZE (0x4da8), but the cell only declared 0x200 bytes. The driver always requests the full buffer, also for the MT7663, so the undersized cell makes the nvmem read fail with -EINVAL. The driver then falls back to default values, which limits TX power to 3 dBm. Fix this by enlarging the cell to 0x4da8. The offset 0x8000 was already correct — offset 0x0 holds the MT7628 (2.4 GHz) calibration data. Fixes: #23632 Signed-off-by: Frank Lang <Frank_Lang@outlook.de> Link: https://github.com/openwrt/openwrt/pull/24284 Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>