FILTR_LPF
filtr = cx25840_read4(c, CX25840_IR_FILTR_REG) & FILTR_LPF;
if (d > FILTR_LPF)
d = FILTR_LPF;
if (d > FILTR_LPF)
d = FILTR_LPF;
u32 filtr = cx23888_ir_read4(dev, CX23888_IR_FILTR_REG) & FILTR_LPF;