bcm2835_i2s_convert_slot  323 sound/soc/bcm/bcm2835-i2s.c 	*ch1_pos = bcm2835_i2s_convert_slot((ffs(mask) - 1), odd_offset)
bcm2835_i2s_convert_slot  325 sound/soc/bcm/bcm2835-i2s.c 	*ch2_pos = bcm2835_i2s_convert_slot((fls(mask) - 1), odd_offset)