UART_IIR           26 arch/powerpc/kernel/udbg_16550.c #define UART_IIR	UART_FCR
UART_IIR           60 arch/sh/include/asm/smc37c93x.h #define UART_IIR	0x4	/* Interrupt Ident Register (Read Only) */
UART_IIR           34 include/uapi/linux/serial_reg.h #define UART_IIR	2	/* In:  Interrupt ID Register */