/sys/kernel/debug/mmc1 # cat ios
clock:          0 Hz
vdd:            0 (invalid)
bus mode:       2 (push-pull)
chip select:    0 (don't care)
power mode:     0 (off)
bus width:      0 (1 bits)
timing spec:    0 (legacy)
signal voltage: 0 (3.30 V)
driver type:    0 (driver type B)