Hi, are you sure you're reading the version in this line?

/* Check product revision. */
if (i2c_read(st->hw->addr, st->reg->accel_offs, 6, data))

How can you get the version from the offset??
Also, the accel_offs is = 0x06, but this register doesn't exists in the MPU6050

In the Mpu6500 the address is correct 0x77 but why do you read the version from the offset?

Thanks