serial: Update NS16550_t and struct NS16550

Typedefs should not be used in U-Boot and structs should be lower case.
Update the code to use struct ns16550 consistently.

Put a header guard on the file while we are here.

Signed-off-by: Simon Glass <sjg@chromium.org>

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
diff --git a/arch/arm/mach-davinci/da850_lowlevel.c b/arch/arm/mach-davinci/da850_lowlevel.c
index 07bf19b..6994ded 100644
--- a/arch/arm/mach-davinci/da850_lowlevel.c
+++ b/arch/arm/mach-davinci/da850_lowlevel.c
@@ -290,8 +290,8 @@
 	board_gpio_init();
 
 #if !CONFIG_IS_ENABLED(DM_SERIAL)
-	NS16550_init((NS16550_t)(CONFIG_SYS_NS16550_COM1),
-			CONFIG_SYS_NS16550_CLK / 16 / CONFIG_BAUDRATE);
+	NS16550_init((struct ns16550 *)(CONFIG_SYS_NS16550_COM1),
+		     CONFIG_SYS_NS16550_CLK / 16 / CONFIG_BAUDRATE);
 #endif
 	/*
 	 * Fix Power and Emulation Management Register
diff --git a/arch/arm/mach-davinci/spl.c b/arch/arm/mach-davinci/spl.c
index 5fea935..3c8330b 100644
--- a/arch/arm/mach-davinci/spl.c
+++ b/arch/arm/mach-davinci/spl.c
@@ -27,9 +27,9 @@
 void putc(char c)
 {
 	if (c == '\n')
-		NS16550_putc((NS16550_t)(CONFIG_SYS_NS16550_COM1), '\r');
+		NS16550_putc((struct ns16550 *)(CONFIG_SYS_NS16550_COM1), '\r');
 
-	NS16550_putc((NS16550_t)(CONFIG_SYS_NS16550_COM1), c);
+	NS16550_putc((struct ns16550 *)(CONFIG_SYS_NS16550_COM1), c);
 }
 #endif /* CONFIG_SPL_LIBCOMMON_SUPPORT */
 
diff --git a/arch/arm/mach-keystone/init.c b/arch/arm/mach-keystone/init.c
index 88e8912..f4edaaa 100644
--- a/arch/arm/mach-keystone/init.c
+++ b/arch/arm/mach-keystone/init.c
@@ -185,7 +185,7 @@
 	 * driver doesn't handle this.
 	 */
 #ifndef CONFIG_DM_SERIAL
-	NS16550_init((NS16550_t)(CONFIG_SYS_NS16550_COM2),
+	NS16550_init((struct ns16550 *)(CONFIG_SYS_NS16550_COM2),
 		     CONFIG_SYS_NS16550_CLK / 16 / CONFIG_BAUDRATE);
 #endif
 
diff --git a/arch/x86/cpu/apollolake/uart.c b/arch/x86/cpu/apollolake/uart.c
index 26aef65..8e6dfdb 100644
--- a/arch/x86/cpu/apollolake/uart.c
+++ b/arch/x86/cpu/apollolake/uart.c
@@ -127,7 +127,7 @@
 	.id	= UCLASS_SERIAL,
 	.of_match = apl_ns16550_serial_ids,
 	.plat_auto	= sizeof(struct ns16550_plat),
-	.priv_auto	= sizeof(struct NS16550),
+	.priv_auto	= sizeof(struct ns16550),
 	.ops	= &ns16550_serial_ops,
 	.of_to_plat = apl_ns16550_of_to_plat,
 	.probe = apl_ns16550_probe,
diff --git a/arch/x86/cpu/slimbootloader/serial.c b/arch/x86/cpu/slimbootloader/serial.c
index 5d89632..ebbd2c5 100644
--- a/arch/x86/cpu/slimbootloader/serial.c
+++ b/arch/x86/cpu/slimbootloader/serial.c
@@ -59,7 +59,7 @@
 	.of_match = slimbootloader_serial_ids,
 	.of_to_plat = slimbootloader_serial_of_to_plat,
 	.plat_auto	= sizeof(struct ns16550_plat),
-	.priv_auto	= sizeof(struct NS16550),
+	.priv_auto	= sizeof(struct ns16550),
 	.probe	= ns16550_serial_probe,
 	.ops	= &ns16550_serial_ops,
 };
diff --git a/board/Arcturus/ucp1020/spl.c b/board/Arcturus/ucp1020/spl.c
index 0fd9532..8e60755 100644
--- a/board/Arcturus/ucp1020/spl.c
+++ b/board/Arcturus/ucp1020/spl.c
@@ -58,7 +58,7 @@
 	bus_clk = CONFIG_SYS_CLK_FREQ * plat_ratio;
 	gd->bus_clk = bus_clk;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
 		     bus_clk / 16 / CONFIG_BAUDRATE);
 #ifdef CONFIG_SPL_MMC_BOOT
 	puts("\nSD boot...\n");
diff --git a/board/Arcturus/ucp1020/spl_minimal.c b/board/Arcturus/ucp1020/spl_minimal.c
index cd0022a..38d84af 100644
--- a/board/Arcturus/ucp1020/spl_minimal.c
+++ b/board/Arcturus/ucp1020/spl_minimal.c
@@ -34,7 +34,7 @@
 	plat_ratio >>= 1;
 	gd->bus_clk = CONFIG_SYS_CLK_FREQ * plat_ratio;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
 		     gd->bus_clk / 16 / CONFIG_BAUDRATE);
 
 	puts("\nNAND boot... ");
@@ -55,9 +55,9 @@
 void putc(char c)
 {
 	if (c == '\n')
-		NS16550_putc((NS16550_t)CONFIG_SYS_NS16550_COM1, '\r');
+		NS16550_putc((struct ns16550 *)CONFIG_SYS_NS16550_COM1, '\r');
 
-	NS16550_putc((NS16550_t)CONFIG_SYS_NS16550_COM1, c);
+	NS16550_putc((struct ns16550 *)CONFIG_SYS_NS16550_COM1, c);
 }
 
 void puts(const char *str)
diff --git a/board/Synology/ds109/ds109.c b/board/Synology/ds109/ds109.c
index aa2987d..c36e4d3 100644
--- a/board/Synology/ds109/ds109.c
+++ b/board/Synology/ds109/ds109.c
@@ -106,10 +106,10 @@
 	printf("Synology reset...");
 	udelay(50000);
 
-	b_d = ns16550_calc_divisor((NS16550_t)CONFIG_SYS_NS16550_COM2,
-		CONFIG_SYS_NS16550_CLK, 9600);
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM2, b_d);
-	NS16550_putc((NS16550_t)CONFIG_SYS_NS16550_COM2, SOFTWARE_REBOOT);
+	b_d = ns16550_calc_divisor((struct ns16550 *)CONFIG_SYS_NS16550_COM2,
+				   CONFIG_SYS_NS16550_CLK, 9600);
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM2, b_d);
+	NS16550_putc((struct ns16550 *)CONFIG_SYS_NS16550_COM2, SOFTWARE_REBOOT);
 }
 
 /* Support old kernels */
diff --git a/board/freescale/mpc8313erdb/mpc8313erdb.c b/board/freescale/mpc8313erdb/mpc8313erdb.c
index 65a10c3..69fa891 100644
--- a/board/freescale/mpc8313erdb/mpc8313erdb.c
+++ b/board/freescale/mpc8313erdb/mpc8313erdb.c
@@ -132,7 +132,7 @@
 void board_init_f(ulong bootflag)
 {
 	board_early_init_f();
-	NS16550_init((NS16550_t)(CONFIG_SYS_IMMR + 0x4500),
+	NS16550_init((struct ns16550 *)(CONFIG_SYS_IMMR + 0x4500),
 		     CONFIG_SYS_NS16550_CLK / 16 / CONFIG_BAUDRATE);
 	puts("NAND boot... ");
 	timer_init();
@@ -152,8 +152,8 @@
 		return;
 
 	if (c == '\n')
-		NS16550_putc((NS16550_t)(CONFIG_SYS_IMMR + 0x4500), '\r');
+		NS16550_putc((struct ns16550 *)(CONFIG_SYS_IMMR + 0x4500), '\r');
 
-	NS16550_putc((NS16550_t)(CONFIG_SYS_IMMR + 0x4500), c);
+	NS16550_putc((struct ns16550 *)(CONFIG_SYS_IMMR + 0x4500), c);
 }
 #endif
diff --git a/board/freescale/mpc8315erdb/mpc8315erdb.c b/board/freescale/mpc8315erdb/mpc8315erdb.c
index f8e4599..fff8699 100644
--- a/board/freescale/mpc8315erdb/mpc8315erdb.c
+++ b/board/freescale/mpc8315erdb/mpc8315erdb.c
@@ -220,7 +220,7 @@
 void board_init_f(ulong bootflag)
 {
 	board_early_init_f();
-	NS16550_init((NS16550_t)(CONFIG_SYS_IMMR + 0x4500),
+	NS16550_init((struct ns16550 *)(CONFIG_SYS_IMMR + 0x4500),
 		     CONFIG_SYS_NS16550_CLK / 16 / CONFIG_BAUDRATE);
 	puts("NAND boot... ");
 	timer_init();
@@ -240,9 +240,9 @@
 		return;
 
 	if (c == '\n')
-		NS16550_putc((NS16550_t)(CONFIG_SYS_IMMR + 0x4500), '\r');
+		NS16550_putc((struct ns16550 *)(CONFIG_SYS_IMMR + 0x4500), '\r');
 
-	NS16550_putc((NS16550_t)(CONFIG_SYS_IMMR + 0x4500), c);
+	NS16550_putc((struct ns16550 *)(CONFIG_SYS_IMMR + 0x4500), c);
 }
 
 #endif /* CONFIG_NAND_SPL */
diff --git a/board/freescale/p1010rdb/spl.c b/board/freescale/p1010rdb/spl.c
index fbaa6a6..c015a6b 100644
--- a/board/freescale/p1010rdb/spl.c
+++ b/board/freescale/p1010rdb/spl.c
@@ -44,7 +44,7 @@
 	plat_ratio >>= 1;
 	gd->bus_clk = CONFIG_SYS_CLK_FREQ * plat_ratio;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
 		     gd->bus_clk / 16 / CONFIG_BAUDRATE);
 
 #ifdef CONFIG_SPL_MMC_BOOT
diff --git a/board/freescale/p1010rdb/spl_minimal.c b/board/freescale/p1010rdb/spl_minimal.c
index 0bb2c83..4cc70ea 100644
--- a/board/freescale/p1010rdb/spl_minimal.c
+++ b/board/freescale/p1010rdb/spl_minimal.c
@@ -31,8 +31,8 @@
 	plat_ratio >>= 1;
 	gd->bus_clk = CONFIG_SYS_CLK_FREQ * plat_ratio;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
-			gd->bus_clk / 16 / CONFIG_BAUDRATE);
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
+		     gd->bus_clk / 16 / CONFIG_BAUDRATE);
 
 	puts("\nNAND boot... ");
 
@@ -53,9 +53,9 @@
 void putc(char c)
 {
 	if (c == '\n')
-		NS16550_putc((NS16550_t)CONFIG_SYS_NS16550_COM1, '\r');
+		NS16550_putc((struct ns16550 *)CONFIG_SYS_NS16550_COM1, '\r');
 
-	NS16550_putc((NS16550_t)CONFIG_SYS_NS16550_COM1, c);
+	NS16550_putc((struct ns16550 *)CONFIG_SYS_NS16550_COM1, c);
 }
 
 void puts(const char *str)
diff --git a/board/freescale/p1_p2_rdb_pc/spl.c b/board/freescale/p1_p2_rdb_pc/spl.c
index 8aceceb..0b8b8a7 100644
--- a/board/freescale/p1_p2_rdb_pc/spl.c
+++ b/board/freescale/p1_p2_rdb_pc/spl.c
@@ -50,7 +50,7 @@
 	bus_clk = CONFIG_SYS_CLK_FREQ * plat_ratio;
 	gd->bus_clk = bus_clk;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
 		     bus_clk / 16 / CONFIG_BAUDRATE);
 #ifdef CONFIG_SPL_MMC_BOOT
 	puts("\nSD boot...\n");
diff --git a/board/freescale/p1_p2_rdb_pc/spl_minimal.c b/board/freescale/p1_p2_rdb_pc/spl_minimal.c
index ced5f3c..7068e94 100644
--- a/board/freescale/p1_p2_rdb_pc/spl_minimal.c
+++ b/board/freescale/p1_p2_rdb_pc/spl_minimal.c
@@ -30,8 +30,8 @@
 	plat_ratio >>= 1;
 	gd->bus_clk = CONFIG_SYS_CLK_FREQ * plat_ratio;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
-			gd->bus_clk / 16 / CONFIG_BAUDRATE);
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
+		     gd->bus_clk / 16 / CONFIG_BAUDRATE);
 
 	puts("\nNAND boot... ");
 
@@ -51,9 +51,9 @@
 void putc(char c)
 {
 	if (c == '\n')
-		NS16550_putc((NS16550_t)CONFIG_SYS_NS16550_COM1, '\r');
+		NS16550_putc((struct ns16550 *)CONFIG_SYS_NS16550_COM1, '\r');
 
-	NS16550_putc((NS16550_t)CONFIG_SYS_NS16550_COM1, c);
+	NS16550_putc((struct ns16550 *)CONFIG_SYS_NS16550_COM1, c);
 }
 
 void puts(const char *str)
diff --git a/board/freescale/t102xrdb/spl.c b/board/freescale/t102xrdb/spl.c
index 09dd88a..d23b2f5 100644
--- a/board/freescale/t102xrdb/spl.c
+++ b/board/freescale/t102xrdb/spl.c
@@ -82,7 +82,7 @@
 	plat_ratio = (in_be32(&gur->rcwsr[0]) >> 25) & 0x1f;
 	ccb_clk = sys_clk * plat_ratio / 2;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
 		     ccb_clk / 16 / CONFIG_BAUDRATE);
 
 #if defined(CONFIG_SPL_MMC_BOOT)
diff --git a/board/freescale/t104xrdb/spl.c b/board/freescale/t104xrdb/spl.c
index e792295..a93cc38 100644
--- a/board/freescale/t104xrdb/spl.c
+++ b/board/freescale/t104xrdb/spl.c
@@ -81,7 +81,7 @@
 	plat_ratio = (in_be32(&gur->rcwsr[0]) >> 25) & 0x1f;
 	uart_clk = sys_clk * plat_ratio / 2;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
 		     uart_clk / 16 / CONFIG_BAUDRATE);
 
 	relocate_code(CONFIG_SPL_RELOC_STACK, (gd_t *)CONFIG_SPL_GD_ADDR, 0x0);
diff --git a/board/freescale/t208xqds/spl.c b/board/freescale/t208xqds/spl.c
index d8c2bbe..c6b23e4 100644
--- a/board/freescale/t208xqds/spl.c
+++ b/board/freescale/t208xqds/spl.c
@@ -81,7 +81,7 @@
 	plat_ratio = (in_be32(&gur->rcwsr[0]) >> 25) & 0x1f;
 	ccb_clk = sys_clk * plat_ratio / 2;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
 		     ccb_clk / 16 / CONFIG_BAUDRATE);
 
 #if defined(CONFIG_SPL_MMC_BOOT)
diff --git a/board/freescale/t208xrdb/spl.c b/board/freescale/t208xrdb/spl.c
index c64bd87..4b84383 100644
--- a/board/freescale/t208xrdb/spl.c
+++ b/board/freescale/t208xrdb/spl.c
@@ -51,7 +51,7 @@
 	plat_ratio = (in_be32(&gur->rcwsr[0]) >> 25) & 0x1f;
 	ccb_clk = sys_clk * plat_ratio / 2;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
 		     ccb_clk / 16 / CONFIG_BAUDRATE);
 
 #if defined(CONFIG_SPL_MMC_BOOT)
diff --git a/board/freescale/t4rdb/spl.c b/board/freescale/t4rdb/spl.c
index 9aa0a9b..efe2b4e 100644
--- a/board/freescale/t4rdb/spl.c
+++ b/board/freescale/t4rdb/spl.c
@@ -60,7 +60,7 @@
 	plat_ratio = (in_be32(&gur->rcwsr[0]) >> 25) & 0x1f;
 	ccb_clk = sys_clk * plat_ratio / 2;
 
-	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
+	NS16550_init((struct ns16550 *)CONFIG_SYS_NS16550_COM1,
 		     ccb_clk / 16 / CONFIG_BAUDRATE);
 
 	puts("\nSD boot...\n");
diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
index 8dd81ad..d529b1b 100644
--- a/drivers/serial/ns16550.c
+++ b/drivers/serial/ns16550.c
@@ -156,7 +156,7 @@
 
 #endif /* CONFIG_NS16550_DYNAMIC */
 
-static void ns16550_writeb(NS16550_t port, int offset, int value)
+static void ns16550_writeb(struct ns16550 *port, int offset, int value)
 {
 	struct ns16550_plat *plat = port->plat;
 	unsigned char *addr;
@@ -170,7 +170,7 @@
 		serial_out_shift(addr, plat->reg_shift, value);
 }
 
-static int ns16550_readb(NS16550_t port, int offset)
+static int ns16550_readb(struct ns16550 *port, int offset)
 {
 	struct ns16550_plat *plat = port->plat;
 	unsigned char *addr;
@@ -184,7 +184,7 @@
 		return serial_in_shift(addr, plat->reg_shift);
 }
 
-static u32 ns16550_getfcr(NS16550_t port)
+static u32 ns16550_getfcr(struct ns16550 *port)
 {
 	struct ns16550_plat *plat = port->plat;
 
@@ -199,20 +199,20 @@
 	ns16550_readb(com_port, \
 		(unsigned char *)addr - (unsigned char *)com_port)
 #else
-static u32 ns16550_getfcr(NS16550_t port)
+static u32 ns16550_getfcr(struct ns16550 *port)
 {
 	return UART_FCR_DEFVAL;
 }
 #endif
 
-int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate)
+int ns16550_calc_divisor(struct ns16550 *port, int clock, int baudrate)
 {
 	const unsigned int mode_x_div = 16;
 
 	return DIV_ROUND_CLOSEST(clock, mode_x_div * baudrate);
 }
 
-static void NS16550_setbrg(NS16550_t com_port, int baud_divisor)
+static void NS16550_setbrg(struct ns16550 *com_port, int baud_divisor)
 {
 	/* to keep serial format, read lcr before writing BKSE */
 	int lcr_val = serial_in(&com_port->lcr) & ~UART_LCR_BKSE;
@@ -223,7 +223,7 @@
 	serial_out(lcr_val, &com_port->lcr);
 }
 
-void NS16550_init(NS16550_t com_port, int baud_divisor)
+void NS16550_init(struct ns16550 *com_port, int baud_divisor)
 {
 #if (defined(CONFIG_SPL_BUILD) && \
 		(defined(CONFIG_OMAP34XX) || defined(CONFIG_OMAP44XX)))
@@ -272,7 +272,7 @@
 }
 
 #ifndef CONFIG_NS16550_MIN_FUNCTIONS
-void NS16550_reinit(NS16550_t com_port, int baud_divisor)
+void NS16550_reinit(struct ns16550 *com_port, int baud_divisor)
 {
 	serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier);
 	NS16550_setbrg(com_port, 0);
@@ -282,7 +282,7 @@
 }
 #endif /* CONFIG_NS16550_MIN_FUNCTIONS */
 
-void NS16550_putc(NS16550_t com_port, char c)
+void NS16550_putc(struct ns16550 *com_port, char c)
 {
 	while ((serial_in(&com_port->lsr) & UART_LSR_THRE) == 0)
 		;
@@ -299,7 +299,7 @@
 }
 
 #ifndef CONFIG_NS16550_MIN_FUNCTIONS
-char NS16550_getc(NS16550_t com_port)
+char NS16550_getc(struct ns16550 *com_port)
 {
 	while ((serial_in(&com_port->lsr) & UART_LSR_DR) == 0) {
 #if !defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_TTY)
@@ -311,7 +311,7 @@
 	return serial_in(&com_port->rbr);
 }
 
-int NS16550_tstc(NS16550_t com_port)
+int NS16550_tstc(struct ns16550 *com_port)
 {
 	return (serial_in(&com_port->lsr) & UART_LSR_DR) != 0;
 }
@@ -324,7 +324,7 @@
 
 static inline void _debug_uart_init(void)
 {
-	struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
+	struct ns16550 *com_port = (struct ns16550 *)CONFIG_DEBUG_UART_BASE;
 	int baud_divisor;
 
 	/*
@@ -345,7 +345,7 @@
 	serial_dout(&com_port->lcr, UART_LCRVAL);
 }
 
-static inline int NS16550_read_baud_divisor(struct NS16550 *com_port)
+static inline int NS16550_read_baud_divisor(struct ns16550 *com_port)
 {
 	int ret;
 
@@ -359,7 +359,7 @@
 
 static inline void _debug_uart_putc(int ch)
 {
-	struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
+	struct ns16550 *com_port = (struct ns16550 *)CONFIG_DEBUG_UART_BASE;
 
 	while (!(serial_din(&com_port->lsr) & UART_LSR_THRE)) {
 #ifdef CONFIG_DEBUG_UART_NS16550_CHECK_ENABLED
@@ -377,7 +377,7 @@
 #if CONFIG_IS_ENABLED(DM_SERIAL)
 static int ns16550_serial_putc(struct udevice *dev, const char ch)
 {
-	struct NS16550 *const com_port = dev_get_priv(dev);
+	struct ns16550 *const com_port = dev_get_priv(dev);
 
 	if (!(serial_in(&com_port->lsr) & UART_LSR_THRE))
 		return -EAGAIN;
@@ -397,7 +397,7 @@
 
 static int ns16550_serial_pending(struct udevice *dev, bool input)
 {
-	struct NS16550 *const com_port = dev_get_priv(dev);
+	struct ns16550 *const com_port = dev_get_priv(dev);
 
 	if (input)
 		return (serial_in(&com_port->lsr) & UART_LSR_DR) ? 1 : 0;
@@ -407,7 +407,7 @@
 
 static int ns16550_serial_getc(struct udevice *dev)
 {
-	struct NS16550 *const com_port = dev_get_priv(dev);
+	struct ns16550 *const com_port = dev_get_priv(dev);
 
 	if (!(serial_in(&com_port->lsr) & UART_LSR_DR))
 		return -EAGAIN;
@@ -417,7 +417,7 @@
 
 static int ns16550_serial_setbrg(struct udevice *dev, int baudrate)
 {
-	struct NS16550 *const com_port = dev_get_priv(dev);
+	struct ns16550 *const com_port = dev_get_priv(dev);
 	struct ns16550_plat *plat = com_port->plat;
 	int clock_divisor;
 
@@ -430,7 +430,7 @@
 
 static int ns16550_serial_setconfig(struct udevice *dev, uint serial_config)
 {
-	struct NS16550 *const com_port = dev_get_priv(dev);
+	struct ns16550 *const com_port = dev_get_priv(dev);
 	int lcr_val = UART_LCR_WLS_8;
 	uint parity = SERIAL_GET_PARITY(serial_config);
 	uint bits = SERIAL_GET_BITS(serial_config);
@@ -464,7 +464,7 @@
 static int ns16550_serial_getinfo(struct udevice *dev,
 				  struct serial_device_info *info)
 {
-	struct NS16550 *const com_port = dev_get_priv(dev);
+	struct ns16550 *const com_port = dev_get_priv(dev);
 	struct ns16550_plat *plat = com_port->plat;
 
 	info->type = SERIAL_CHIP_16550_COMPATIBLE;
@@ -499,7 +499,7 @@
 int ns16550_serial_probe(struct udevice *dev)
 {
 	struct ns16550_plat *plat = dev->plat;
-	struct NS16550 *const com_port = dev_get_priv(dev);
+	struct ns16550 *const com_port = dev_get_priv(dev);
 	struct reset_ctl_bulk reset_bulk;
 	fdt_addr_t addr;
 	int ret;
@@ -613,7 +613,7 @@
 	.of_to_plat = ns16550_serial_of_to_plat,
 	.plat_auto	= sizeof(struct ns16550_plat),
 #endif
-	.priv_auto	= sizeof(struct NS16550),
+	.priv_auto	= sizeof(struct ns16550),
 	.probe = ns16550_serial_probe,
 	.ops	= &ns16550_serial_ops,
 #if !CONFIG_IS_ENABLED(OF_CONTROL)
diff --git a/drivers/serial/serial_coreboot.c b/drivers/serial/serial_coreboot.c
index 904e1b3..88c8209 100644
--- a/drivers/serial/serial_coreboot.c
+++ b/drivers/serial/serial_coreboot.c
@@ -37,7 +37,7 @@
 	.name	= "coreboot_uart",
 	.id	= UCLASS_SERIAL,
 	.of_match	= coreboot_serial_ids,
-	.priv_auto	= sizeof(struct NS16550),
+	.priv_auto	= sizeof(struct ns16550),
 	.plat_auto	= sizeof(struct ns16550_plat),
 	.of_to_plat  = coreboot_of_to_plat,
 	.probe	= ns16550_serial_probe,
diff --git a/drivers/serial/serial_intel_mid.c b/drivers/serial/serial_intel_mid.c
index be9bf66..bbf1905 100644
--- a/drivers/serial/serial_intel_mid.c
+++ b/drivers/serial/serial_intel_mid.c
@@ -61,7 +61,7 @@
 	.of_match = mid_serial_ids,
 	.of_to_plat = ns16550_serial_of_to_plat,
 	.plat_auto	= sizeof(struct ns16550_plat),
-	.priv_auto	= sizeof(struct NS16550),
+	.priv_auto	= sizeof(struct ns16550),
 	.probe	= mid_serial_probe,
 	.ops	= &ns16550_serial_ops,
 };
diff --git a/drivers/serial/serial_ns16550.c b/drivers/serial/serial_ns16550.c
index ef394b7..a8d3602 100644
--- a/drivers/serial/serial_ns16550.c
+++ b/drivers/serial/serial_ns16550.c
@@ -36,34 +36,34 @@
 /* Note: The port number specified in the functions is 1 based.
  *	 the array is 0 based.
  */
-static NS16550_t serial_ports[6] = {
+static struct ns16550 *serial_ports[6] = {
 #ifdef CONFIG_SYS_NS16550_COM1
-	(NS16550_t)CONFIG_SYS_NS16550_COM1,
+	(struct ns16550 *)CONFIG_SYS_NS16550_COM1,
 #else
 	NULL,
 #endif
 #ifdef CONFIG_SYS_NS16550_COM2
-	(NS16550_t)CONFIG_SYS_NS16550_COM2,
+	(struct ns16550 *)CONFIG_SYS_NS16550_COM2,
 #else
 	NULL,
 #endif
 #ifdef CONFIG_SYS_NS16550_COM3
-	(NS16550_t)CONFIG_SYS_NS16550_COM3,
+	(struct ns16550 *)CONFIG_SYS_NS16550_COM3,
 #else
 	NULL,
 #endif
 #ifdef CONFIG_SYS_NS16550_COM4
-	(NS16550_t)CONFIG_SYS_NS16550_COM4,
+	(struct ns16550 *)CONFIG_SYS_NS16550_COM4,
 #else
 	NULL,
 #endif
 #ifdef CONFIG_SYS_NS16550_COM5
-	(NS16550_t)CONFIG_SYS_NS16550_COM5,
+	(struct ns16550 *)CONFIG_SYS_NS16550_COM5,
 #else
 	NULL,
 #endif
 #ifdef CONFIG_SYS_NS16550_COM6
-	(NS16550_t)CONFIG_SYS_NS16550_COM6
+	(struct ns16550 *)CONFIG_SYS_NS16550_COM6
 #else
 	NULL
 #endif
diff --git a/drivers/serial/serial_omap.c b/drivers/serial/serial_omap.c
index 2f38e1b..c235215 100644
--- a/drivers/serial/serial_omap.c
+++ b/drivers/serial/serial_omap.c
@@ -66,7 +66,7 @@
 
 static inline void _debug_uart_init(void)
 {
-	struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
+	struct ns16550 *com_port = (struct ns16550 *)CONFIG_DEBUG_UART_BASE;
 	int baud_divisor;
 
 	baud_divisor = ns16550_calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
@@ -85,7 +85,7 @@
 
 static inline void _debug_uart_putc(int ch)
 {
-	struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
+	struct ns16550 *com_port = (struct ns16550 *)CONFIG_DEBUG_UART_BASE;
 
 	while (!(serial_din(&com_port->lsr) & UART_LSR_THRE))
 		;
@@ -160,7 +160,7 @@
 	.of_to_plat = omap_serial_of_to_plat,
 	.plat_auto	= sizeof(struct ns16550_plat),
 #endif
-	.priv_auto	= sizeof(struct NS16550),
+	.priv_auto	= sizeof(struct ns16550),
 	.probe = ns16550_serial_probe,
 	.ops	= &ns16550_serial_ops,
 #if !CONFIG_IS_ENABLED(OF_CONTROL)
diff --git a/drivers/serial/serial_rockchip.c b/drivers/serial/serial_rockchip.c
index 4c0548e..036c072 100644
--- a/drivers/serial/serial_rockchip.c
+++ b/drivers/serial/serial_rockchip.c
@@ -42,7 +42,7 @@
 U_BOOT_DRIVER(rockchip_rk3188_uart) = {
 	.name	= "rockchip_rk3188_uart",
 	.id	= UCLASS_SERIAL,
-	.priv_auto	= sizeof(struct NS16550),
+	.priv_auto	= sizeof(struct ns16550),
 	.plat_auto	= sizeof(struct rockchip_uart_plat),
 	.probe	= rockchip_serial_probe,
 	.ops	= &ns16550_serial_ops,
@@ -52,7 +52,7 @@
 U_BOOT_DRIVER(rockchip_rk3288_uart) = {
 	.name	= "rockchip_rk3288_uart",
 	.id	= UCLASS_SERIAL,
-	.priv_auto	= sizeof(struct NS16550),
+	.priv_auto	= sizeof(struct ns16550),
 	.plat_auto	= sizeof(struct rockchip_uart_plat),
 	.probe	= rockchip_serial_probe,
 	.ops	= &ns16550_serial_ops,
diff --git a/include/ns16550.h b/include/ns16550.h
index bef2961..75c5bf6 100644
--- a/include/ns16550.h
+++ b/include/ns16550.h
@@ -21,6 +21,9 @@
  * will not allocate storage for arrays of size 0
  */
 
+#ifndef __ns16550_h
+#define __ns16550_h
+
 #include <linux/types.h>
 
 #ifdef CONFIG_DM_SERIAL
@@ -82,7 +85,7 @@
 
 struct udevice;
 
-struct NS16550 {
+struct ns16550 {
 	UART_REG(rbr);		/* 0 */
 	UART_REG(ier);		/* 1 */
 	UART_REG(fcr);		/* 2 */
@@ -120,8 +123,6 @@
 #define dll rbr
 #define dlm ier
 
-typedef struct NS16550 *NS16550_t;
-
 /*
  * These are the definitions for the FIFO Control Register
  */
@@ -221,11 +222,11 @@
 /* useful defaults for LCR */
 #define UART_LCR_8N1	0x03
 
-void NS16550_init(NS16550_t com_port, int baud_divisor);
-void NS16550_putc(NS16550_t com_port, char c);
-char NS16550_getc(NS16550_t com_port);
-int NS16550_tstc(NS16550_t com_port);
-void NS16550_reinit(NS16550_t com_port, int baud_divisor);
+void NS16550_init(struct ns16550 *com_port, int baud_divisor);
+void NS16550_putc(struct ns16550 *com_port, char c);
+char NS16550_getc(struct ns16550 *com_port);
+int NS16550_tstc(struct ns16550 *com_port);
+void NS16550_reinit(struct ns16550 *com_port, int baud_divisor);
 
 /**
  * ns16550_calc_divisor() - calculate the divisor given clock and baud rate
@@ -238,7 +239,7 @@
  * @baudrate:	Required baud rate
  * @return baud rate divisor that should be used
  */
-int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate);
+int ns16550_calc_divisor(struct ns16550 *port, int clock, int baudrate);
 
 /**
  * ns16550_serial_of_to_plat() - convert DT to platform data
@@ -266,3 +267,5 @@
  * These should be used by the client driver for the driver's 'ops' member
  */
 extern const struct dm_serial_ops ns16550_serial_ops;
+
+#endif /* __ns16550_h */
diff --git a/lib/efi/efi_stub.c b/lib/efi/efi_stub.c
index 7d650d5..b3393e4 100644
--- a/lib/efi/efi_stub.c
+++ b/lib/efi/efi_stub.c
@@ -67,7 +67,7 @@
 		putc('\r');
 
 	if (use_uart) {
-		NS16550_t com_port = (NS16550_t)0x3f8;
+		struct ns16550 *com_port = (struct ns16550 *)0x3f8;
 
 		while ((inb((ulong)&com_port->lsr) & UART_LSR_THRE) == 0)
 			;