serial: Move carriage return before line feed for some serial drivers

In general, a carriage return needs to execute before a line feed.
The patch is to change some serial drivers based on this rule, such
as serial_mxc.c, serial_pxa.c, serial_s3c24x0.c and usbtty.c.

Signed-off-by: Alison Wang <alison.wang@nxp.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

drivers/serial/serial_mxc.c

@@ -164,15 +164,15 @@ static int mxc_serial_getc(void)
 
 static void mxc_serial_putc(const char c)
 {
+	/* If \n, also do \r */
+	if (c == '\n')
+		serial_putc('\r');
+
 	__REG(UART_PHYS + UTXD) = c;
 
 	/* wait for transmitter to be ready */
 	while (!(__REG(UART_PHYS + UTS) & UTS_TXEMPTY))
 		WATCHDOG_RESET();
-
-	/* If \n, also do \r */
-	if (c == '\n')
-		serial_putc ('\r');
 }
 
 /*

drivers/serial/serial_pxa.c

@@ -156,6 +156,10 @@ void pxa_putc_dev(unsigned int uart_index, const char c)
 {
 	struct pxa_uart_regs *uart_regs;
 
+	/* If \n, also do \r */
+	if (c == '\n')
+		pxa_putc_dev(uart_index, '\r');
+
 	uart_regs = pxa_uart_index_to_regs(uart_index);
 	if (!uart_regs)
 		hang();
@@ -163,10 +167,6 @@ void pxa_putc_dev(unsigned int uart_index, const char c)
 	while (!(readl(&uart_regs->lsr) & LSR_TEMT))
 		WATCHDOG_RESET();
 	writel(c, &uart_regs->thr);
-
-	/* If \n, also do \r */
-	if (c == '\n')
-		pxa_putc_dev (uart_index,'\r');
 }
 
 /*

drivers/serial/serial_s3c24x0.c

@@ -135,14 +135,14 @@ static void _serial_putc(const char c, const int dev_index)
 {
 	struct s3c24x0_uart *uart = s3c24x0_get_base_uart(dev_index);
 
+	/* If \n, also do \r */
+	if (c == '\n')
+		serial_putc('\r');
+
 	while (!(readl(&uart->utrstat) & 0x2))
 		/* wait for room in the tx FIFO */ ;
 
 	writeb(c, &uart->utxh);
-
-	/* If \n, also do \r */
-	if (c == '\n')
-		serial_putc('\r');
 }
 
 static inline void serial_putc_dev(unsigned int dev_index, const char c)

drivers/serial/usbtty.c

@@ -434,11 +434,12 @@ void usbtty_putc(struct stdio_dev *dev, const char c)
 	if (!usbtty_configured ())
 		return;
 
-	buf_push (&usbtty_output, &c, 1);
 	/* If \n, also do \r */
 	if (c == '\n')
 		buf_push (&usbtty_output, "\r", 1);
 
+	buf_push(&usbtty_output, &c, 1);
+
 	/* Poll at end to handle new data... */
 	if ((usbtty_output.size + 2) >= usbtty_output.totalsize) {
 		usbtty_poll ();
@@ -498,8 +499,8 @@ void usbtty_puts(struct stdio_dev *dev, const char *str)
 		n = next_nl_pos (str);
 
 		if (str[n] == '\n') {
-			__usbtty_puts (str, n + 1);
-			__usbtty_puts ("\r", 1);
+			__usbtty_puts("\r", 1);
+			__usbtty_puts(str, n + 1);
 			str += (n + 1);
 			len -= (n + 1);
 		} else {