root@multi-v7-ml:/sys/kernel/debug# ls
2100000.crypto  bluetooth        devfreq           dmaengine      fault_around_bytes  interconnect  mtd       psci           regmap      slab           tracing  usb
bcm7271-uart    cec              device_component  dri            gpio                kprobes       opp       pwm            regulator   sleep_time     ubi      virtio-ports
bdi             clear_warn_once  devices_deferred  dynamic_debug  hid                 memblock      pinctrl   ramdisk_pages  remoteproc  stmmaceth      ubifs    wakeup_sources
block           clk              dma_buf           extfrag        iio                 mmc0          pm_genpd  ras            sched       suspend_stats  ulpi