[SERIAL] kernel console should send CRLF not LFCR

Glen Turner reported that writing LFCR rather than the more
traditional CRLF causes issues with some terminals.

Since this aflicts many serial drivers, extract the common code
to a library function (uart_console_write) and arrange for each
driver to supply a "putchar" function.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 5 insertions, 15 deletions

diff --git a/drivers/serial/amba-pl011.c b/drivers/serial/amba-pl011.c
index 034a029e356..3d966cfc9a3 100644
--- a/drivers/serial/amba-pl011.c
+++ b/drivers/serial/amba-pl011.c
@@ -587,14 +587,12 @@ static struct uart_amba_port *amba_ports[UART_NR];
 
 #ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE
 
-static inline void
-pl011_console_write_char(struct uart_amba_port *uap, char ch)
+static void pl011_console_putchar(struct uart_port *port, int ch)
 {
-        unsigned int status;
+        struct uart_amba_port *uap = (struct uart_amba_port *)port;
 
-        do {
-                status = readw(uap->port.membase + UART01x_FR);
-        } while (status & UART01x_FR_TXFF);
+        while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF)
+                barrier();
         writew(ch, uap->port.membase + UART01x_DR);
 }
 
@@ -603,7 +601,6 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
 {
         struct uart_amba_port *uap = amba_ports[co->index];
         unsigned int status, old_cr, new_cr;
-        int i;
 
         clk_enable(uap->clk);
 
@@ -615,14 +612,7 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
         new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
         writew(new_cr, uap->port.membase + UART011_CR);
 
-        /*
-         *      Now, do each character
-         */
-        for (i = 0; i < count; i++) {
-                pl011_console_write_char(uap, s[i]);
-                if (s[i] == '\n')
-                        pl011_console_write_char(uap, '\r');
-        }
+        uart_console_write(&uap->port, s, count, pl011_console_putchar);
 
         /*
          *      Finally, wait for transmitter to become empty