serial: arm: Implement CONFIG_SERIAL_MULTI into lpc32xx serial driver

Implement support for CONFIG_SERIAL_MULTI into lpc32xx serial driver.
This driver was so far only usable directly, but this patch also adds
support for the multi method. This allows using more than one serial
driver alongside the lpc32xx driver. Also, add a weak implementation
of default_serial_console() returning this driver.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Tom Rini <trini@ti.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>

common/serial.c

@@ -73,6 +73,7 @@ serial_initfunc(p3mx_serial_initialize);
 serial_initfunc(altera_jtag_serial_initialize);
 serial_initfunc(altera_serial_initialize);
 serial_initfunc(atmel_serial_initialize);
+serial_initfunc(lpc32xx_serial_initialize);
 
 void serial_register(struct serial_device *dev)
 {
@@ -124,6 +125,7 @@ void serial_initialize(void)
 	altera_jtag_serial_initialize();
 	altera_serial_initialize();
 	atmel_serial_initialize();
+	lpc32xx_serial_initialize();
 
 	serial_assign(default_serial_console()->name);
 }

drivers/serial/lpc32xx_hsuart.c

@@ -22,12 +22,14 @@
 #include <asm/arch/clk.h>
 #include <asm/arch/uart.h>
 #include <asm/io.h>
+#include <serial.h>
+#include <linux/compiler.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
 static struct hsuart_regs *hsuart = (struct hsuart_regs *)HS_UART_BASE;
 
-static void lpc32xx_hsuart_set_baudrate(void)
+static void lpc32xx_serial_setbrg(void)
 {
 	u32 div;
 
@@ -39,7 +41,7 @@ static void lpc32xx_hsuart_set_baudrate(void)
 	writel(div, &hsuart->rate);
 }
 
-static int lpc32xx_hsuart_getc(void)
+static int lpc32xx_serial_getc(void)
 {
 	while (!(readl(&hsuart->level) & HSUART_LEVEL_RX))
 		/* NOP */;
@@ -47,7 +49,7 @@ static int lpc32xx_hsuart_getc(void)
 	return readl(&hsuart->rx) & HSUART_RX_DATA;
 }
 
-static void lpc32xx_hsuart_putc(const char c)
+static void lpc32xx_serial_putc(const char c)
 {
 	writel(c, &hsuart->tx);
 
@@ -56,7 +58,7 @@ static void lpc32xx_hsuart_putc(const char c)
 		/* NOP */;
 }
 
-static int lpc32xx_hsuart_tstc(void)
+static int lpc32xx_serial_tstc(void)
 {
 	if (readl(&hsuart->level) & HSUART_LEVEL_RX)
 		return 1;
@@ -64,49 +66,72 @@ static int lpc32xx_hsuart_tstc(void)
 	return 0;
 }
 
-static void lpc32xx_hsuart_init(void)
+static int lpc32xx_serial_init(void)
 {
-	lpc32xx_hsuart_set_baudrate();
+	lpc32xx_serial_setbrg();
 
 	/* Disable hardware RTS and CTS flow control, set up RX and TX FIFO */
 	writel(HSUART_CTRL_TMO_16 | HSUART_CTRL_HSU_OFFSET(20) |
 	       HSUART_CTRL_HSU_RX_TRIG_32 | HSUART_CTRL_HSU_TX_TRIG_0,
 	       &hsuart->ctrl);
+	return 0;
 }
 
-void serial_setbrg(void)
+static void lpc32xx_serial_puts(const char *s)
 {
-	return lpc32xx_hsuart_set_baudrate();
+	while (*s)
+		serial_putc(*s++);
 }
 
-void serial_putc(const char c)
+#ifdef CONFIG_SERIAL_MULTI
+static struct serial_device lpc32xx_serial_drv = {
+	.name	= "lpc32xx_serial",
+	.start	= lpc32xx_serial_init,
+	.stop	= NULL,
+	.setbrg	= lpc32xx_serial_setbrg,
+	.putc	= lpc32xx_serial_putc,
+	.puts	= lpc32xx_serial_puts,
+	.getc	= lpc32xx_serial_getc,
+	.tstc	= lpc32xx_serial_tstc,
+};
+
+void lpc32xx_serial_initialize(void)
 {
-	lpc32xx_hsuart_putc(c);
+	serial_register(&lpc32xx_serial_drv);
+}
 
-	/* If \n, also do \r */
-	if (c == '\n')
-		lpc32xx_hsuart_putc('\r');
+__weak struct serial_device *default_serial_console(void)
+{
+	return &lpc32xx_serial_drv;
+}
+#else
+int serial_init(void)
+{
+	return lpc32xx_serial_init();
 }
 
-int serial_getc(void)
+void serial_setbrg(void)
 {
-	return lpc32xx_hsuart_getc();
+	lpc32xx_serial_setbrg();
 }
 
-void serial_puts(const char *s)
+void serial_putc(const char c)
 {
-	while (*s)
-		serial_putc(*s++);
+	lpc32xx_serial_putc(c);
 }
 
-int serial_tstc(void)
+void serial_puts(const char *s)
 {
-	return lpc32xx_hsuart_tstc();
+	lpc32xx_serial_puts(s);
 }
 
-int serial_init(void)
+int serial_getc(void)
 {
-	lpc32xx_hsuart_init();
+	return lpc32xx_serial_getc();
+}
 
-	return 0;
+int serial_tstc(void)
+{
+	return lpc32xx_serial_tstc();
 }
+#endif