[PATCH] m68k / serial: mcf.c: avoid recomputing 'port' in mcf_console_putc.

Let's `mcf_console_putc' require a `struct uart_port *' instead of a
`struct console *'.  This makes cleaner and slightly more efficient
code, and also makes mcf_console_putc easier to use for early debugging.

Signed-off-by: Philippe De Muyter <[email protected]>
---
 drivers/tty/serial/mcf.c |   32 ++++++++++++++++++++------------
 1 files changed, 20 insertions(+), 12 deletions(-)

On Tue, Jan 15, 2013 at 11:28:38PM +1000, Greg Ungerer wrote:
> If you are getting into the kernel startup code, then take the trace
> up to the C code level. Code up a simple console char output routine
> (use the serial driver console routines as an example).

diff --git a/drivers/tty/serial/mcf.c b/drivers/tty/serial/mcf.c
index fcd56ab..5f60382 100644
--- a/drivers/tty/serial/mcf.c
+++ b/drivers/tty/serial/mcf.c
@@ -473,31 +473,39 @@ int __init early_mcf_setup(struct mcf_platform_uart *platp)
 
 /****************************************************************************/
 
-static void mcf_console_putc(struct console *co, const char c)
+static inline void mcf_console_wait(struct uart_port *port, unsigned char condition)
 {
-	struct uart_port *port = &(mcf_ports + co->index)->port;
 	int i;
 
-	for (i = 0; (i < 0x10000); i++) {
-		if (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY)
+	for (i = 0; i < 0x10000; i++) {
+		if (readb(port->membase + MCFUART_USR) & condition)
 			break;
 	}
+}
+
+/****************************************************************************/
+
+static void mcf_console_putc(struct uart_port *port, const char c)
+{
+
+	mcf_console_wait(port, MCFUART_USR_TXREADY);
 	writeb(c, port->membase + MCFUART_UTB);
-	for (i = 0; (i < 0x10000); i++) {
-		if (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY)
-			break;
-	}
 }
 
 /****************************************************************************/
 
 static void mcf_console_write(struct console *co, const char *s, unsigned int count)
 {
-	for (; (count); count--, s++) {
-		mcf_console_putc(co, *s);
-		if (*s == '\n')
-			mcf_console_putc(co, '\r');
+	struct uart_port *port = &(mcf_ports + co->index)->port;
+
+	while (count--) {
+		unsigned char c = *s++;
+
+		mcf_console_putc(port, c);
+		if (c == '\n')
+			mcf_console_putc(port, '\r');
 	}
+	mcf_console_wait(port, MCFUART_USR_TXEMPTY);
 }
 
 /****************************************************************************/
-- 
1.7.1

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