diff --git a/include/linux/serial.h b/include/linux/serial.h
index 9136cc5..e5bb75a 100644
--- a/include/linux/serial.h
+++ b/include/linux/serial.h
@@ -96,54 +96,76 @@
 
 /*
  * Definitions for async_struct (and serial_struct) flags field
+ *
+ * Define ASYNCB_* for convenient use with {test,set,clear}_bit.
  */
-#define ASYNC_HUP_NOTIFY 0x0001 /* Notify getty on hangups and closes 
-				   on the callout port */
-#define ASYNC_FOURPORT  0x0002	/* Set OU1, OUT2 per AST Fourport settings */
-#define ASYNC_SAK	0x0004	/* Secure Attention Key (Orange book) */
-#define ASYNC_SPLIT_TERMIOS 0x0008 /* Separate termios for dialin/callout */
+#define ASYNCB_HUP_NOTIFY	 0 /* Notify getty on hangups and closes
+				    * on the callout port */
+#define ASYNCB_FOURPORT		 1 /* Set OU1, OUT2 per AST Fourport settings */
+#define ASYNCB_SAK		 2 /* Secure Attention Key (Orange book) */
+#define ASYNCB_SPLIT_TERMIOS	 3 /* Separate termios for dialin/callout */
+#define ASYNCB_SPD_HI		 4 /* Use 56000 instead of 38400 bps */
+#define ASYNCB_SPD_VHI		 5 /* Use 115200 instead of 38400 bps */
+#define ASYNCB_SKIP_TEST	 6 /* Skip UART test during autoconfiguration */
+#define ASYNCB_AUTO_IRQ		 7 /* Do automatic IRQ during
+				    * autoconfiguration */
+#define ASYNCB_SESSION_LOCKOUT	 8 /* Lock out cua opens based on session */
+#define ASYNCB_PGRP_LOCKOUT	 9 /* Lock out cua opens based on pgrp */
+#define ASYNCB_CALLOUT_NOHUP	10 /* Don't do hangups for cua device */
+#define ASYNCB_HARDPPS_CD	11 /* Call hardpps when CD goes high  */
+#define ASYNCB_SPD_SHI		12 /* Use 230400 instead of 38400 bps */
+#define ASYNCB_LOW_LATENCY	13 /* Request low latency behaviour */
+#define ASYNCB_BUGGY_UART	14 /* This is a buggy UART, skip some safety
+				    * checks.  Note: can be dangerous! */
+#define ASYNCB_AUTOPROBE	15 /* Port was autoprobed by PCI or PNP code */
+#define ASYNCB_LAST_USER	15
 
-#define ASYNC_SPD_MASK	0x1030
-#define ASYNC_SPD_HI	0x0010	/* Use 56000 instead of 38400 bps */
+/* Internal flags used only by kernel */
+#define ASYNCB_INITIALIZED	31 /* Serial port was initialized */
+#define ASYNCB_NORMAL_ACTIVE	29 /* Normal device is active */
+#define ASYNCB_BOOT_AUTOCONF	28 /* Autoconfigure port on bootup */
+#define ASYNCB_CLOSING		27 /* Serial port is closing */
+#define ASYNCB_CTS_FLOW		26 /* Do CTS flow control */
+#define ASYNCB_CHECK_CD		25 /* i.e., CLOCAL */
+#define ASYNCB_SHARE_IRQ	24 /* for multifunction cards, no longer used */
+#define ASYNCB_CONS_FLOW	23 /* flow control for console  */
+#define ASYNCB_BOOT_ONLYMCA	22 /* Probe only if MCA bus */
+#define ASYNCB_FIRST_KERNEL	22
 
-#define ASYNC_SPD_VHI	0x0020  /* Use 115200 instead of 38400 bps */
-#define ASYNC_SPD_CUST	0x0030  /* Use user-specified divisor */
+#define ASYNC_HUP_NOTIFY	(1U << ASYNCB_HUP_NOTIFY)
+#define ASYNC_FOURPORT		(1U << ASYNCB_FOURPORT)
+#define ASYNC_SAK		(1U << ASYNCB_SAK)
+#define ASYNC_SPLIT_TERMIOS	(1U << ASYNCB_SPLIT_TERMIOS)
+#define ASYNC_SPD_HI		(1U << ASYNCB_SPD_HI)
+#define ASYNC_SPD_VHI		(1U << ASYNCB_SPD_VHI)
+#define ASYNC_SKIP_TEST		(1U << ASYNCB_SKIP_TEST)
+#define ASYNC_AUTO_IRQ		(1U << ASYNCB_AUTO_IRQ)
+#define ASYNC_SESSION_LOCKOUT	(1U << ASYNCB_SESSION_LOCKOUT)
+#define ASYNC_PGRP_LOCKOUT	(1U << ASYNCB_PGRP_LOCKOUT)
+#define ASYNC_CALLOUT_NOHUP	(1U << ASYNCB_CALLOUT_NOHUP)
+#define ASYNC_HARDPPS_CD	(1U << ASYNCB_HARDPPS_CD)
+#define ASYNC_SPD_SHI		(1U << ASYNCB_SPD_SHI)
+#define ASYNC_LOW_LATENCY	(1U << ASYNCB_LOW_LATENCY)
+#define ASYNC_BUGGY_UART	(1U << ASYNCB_BUGGY_UART)
+#define ASYNC_AUTOPROBE		(1U << ASYNCB_AUTOPROBE)
 
-#define ASYNC_SKIP_TEST	0x0040 /* Skip UART test during autoconfiguration */
-#define ASYNC_AUTO_IRQ  0x0080 /* Do automatic IRQ during autoconfiguration */
-#define ASYNC_SESSION_LOCKOUT 0x0100 /* Lock out cua opens based on session */
-#define ASYNC_PGRP_LOCKOUT    0x0200 /* Lock out cua opens based on pgrp */
-#define ASYNC_CALLOUT_NOHUP   0x0400 /* Don't do hangups for cua device */
+#define ASYNC_FLAGS		((1U << ASYNCB_LAST_USER) - 1)
+#define ASYNC_USR_MASK		(ASYNC_SPD_HI|ASYNC_SPD_VHI| \
+		ASYNC_CALLOUT_NOHUP|ASYNC_SPD_SHI|ASYNC_LOW_LATENCY)
+#define ASYNC_SPD_CUST		(ASYNC_SPD_HI|ASYNC_SPD_VHI)
+#define ASYNC_SPD_WARP		(ASYNC_SPD_HI|ASYNC_SPD_SHI)
+#define ASYNC_SPD_MASK		(ASYNC_SPD_HI|ASYNC_SPD_VHI|ASYNC_SPD_SHI)
 
-#define ASYNC_HARDPPS_CD	0x0800	/* Call hardpps when CD goes high  */
-
-#define ASYNC_SPD_SHI	0x1000	/* Use 230400 instead of 38400 bps */
-#define ASYNC_SPD_WARP	0x1010	/* Use 460800 instead of 38400 bps */
-
-#define ASYNC_LOW_LATENCY 0x2000 /* Request low latency behaviour */
-
-#define ASYNC_BUGGY_UART  0x4000 /* This is a buggy UART, skip some safety
-				  * checks.  Note: can be dangerous! */
-
-#define ASYNC_AUTOPROBE	 0x8000 /* Port was autoprobed by PCI or PNP code */
-
-#define ASYNC_FLAGS	0x7FFF	/* Possible legal async flags */
-#define ASYNC_USR_MASK	0x3430	/* Legal flags that non-privileged
-				 * users can set or reset */
-
-/* Internal flags used only by kernel/chr_drv/serial.c */
-#define ASYNC_INITIALIZED	0x80000000 /* Serial port was initialized */
-#define ASYNC_NORMAL_ACTIVE	0x20000000 /* Normal device is active */
-#define ASYNC_BOOT_AUTOCONF	0x10000000 /* Autoconfigure port on bootup */
-#define ASYNC_CLOSING		0x08000000 /* Serial port is closing */
-#define ASYNC_CTS_FLOW		0x04000000 /* Do CTS flow control */
-#define ASYNC_CHECK_CD		0x02000000 /* i.e., CLOCAL */
-#define ASYNC_SHARE_IRQ		0x01000000 /* for multifunction cards
-					     --- no longer used */
-#define ASYNC_CONS_FLOW		0x00800000 /* flow control for console  */
-
-#define ASYNC_BOOT_ONLYMCA	0x00400000 /* Probe only if MCA bus */
-#define ASYNC_INTERNAL_FLAGS	0xFFC00000 /* Internal flags */
+#define ASYNC_INITIALIZED	(1U << ASYNCB_INITIALIZED)
+#define ASYNC_NORMAL_ACTIVE	(1U << ASYNCB_NORMAL_ACTIVE)
+#define ASYNC_BOOT_AUTOCONF	(1U << ASYNCB_BOOT_AUTOCONF)
+#define ASYNC_CLOSING		(1U << ASYNCB_CLOSING)
+#define ASYNC_CTS_FLOW		(1U << ASYNCB_CTS_FLOW)
+#define ASYNC_CHECK_CD		(1U << ASYNCB_CHECK_CD)
+#define ASYNC_SHARE_IRQ		(1U << ASYNCB_SHARE_IRQ)
+#define ASYNC_CONS_FLOW		(1U << ASYNCB_CONS_FLOW)
+#define ASYNC_BOOT_ONLYMCA	(1U << ASYNCB_BOOT_ONLYMCA)
+#define ASYNC_INTERNAL_FLAGS	(~((1U << ASYNCB_FIRST_KERNEL) - 1))
 
 /*
  * Multiport serial configuration structure --- external structure