openwrt-xburst/target/linux/ramips/patches-2.6.32/101-rt288x_serial_driver_hack.patch

--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -301,9 +301,9 @@ static const struct serial8250_config ua
 	},
 };
 
-#if defined (CONFIG_SERIAL_8250_AU1X00)
+#if defined (CONFIG_SERIAL_8250_AU1X00) || defined (CONFIG_SERIAL_8250_RT288X)
 
-/* Au1x00 UART hardware has a weird register layout */
+/* Au1x00 and RT288x UART hardware has a weird register layout */
 static const u8 au_io_in_map[] = {
 	[UART_RX]  = 0,
 	[UART_IER] = 2,
@@ -421,7 +421,7 @@ static unsigned int mem32_serial_in(stru
 	return readl(p->membase + offset);
 }
 
-#ifdef CONFIG_SERIAL_8250_AU1X00
+#if defined(CONFIG_SERIAL_8250_AU1X00) || defined(CONFIG_SERIAL_8250_RT288X)
 static unsigned int au_serial_in(struct uart_port *p, int offset)
 {
 	offset = map_8250_in_reg(p, offset) << p->regshift;
@@ -502,7 +502,7 @@ static void set_io_from_upio(struct uart
 		p->serial_out = mem32_serial_out;
 		break;
 
-#ifdef CONFIG_SERIAL_8250_AU1X00
+#if defined (CONFIG_SERIAL_8250_AU1X00) || defined (CONFIG_SERIAL_8250_RT288X)
 	case UPIO_AU:
 		p->serial_in = au_serial_in;
 		p->serial_out = au_serial_out;
@@ -534,7 +534,7 @@ serial_out_sync(struct uart_8250_port *u
 	switch (p->iotype) {
 	case UPIO_MEM:
 	case UPIO_MEM32:
-#ifdef CONFIG_SERIAL_8250_AU1X00
+#if defined (CONFIG_SERIAL_8250_AU1X00) || defined (CONFIG_SERIAL_8250_RT288X)
 	case UPIO_AU:
 #endif
 	case UPIO_DWAPB:
@@ -572,8 +572,8 @@ static inline void _serial_dl_write(stru
 	serial_outp(up, UART_DLM, value >> 8 & 0xff);
 }
 
-#if defined(CONFIG_SERIAL_8250_AU1X00)
-/* Au1x00 haven't got a standard divisor latch */
+#if defined (CONFIG_SERIAL_8250_AU1X00) || defined (CONFIG_SERIAL_8250_RT288X)
+/* Au1x00 and RT288x haven't got a standard divisor latch */
 static int serial_dl_read(struct uart_8250_port *up)
 {
 	if (up->port.iotype == UPIO_AU)
@@ -780,22 +780,19 @@ static int size_fifo(struct uart_8250_po
  */
 static unsigned int autoconfig_read_divisor_id(struct uart_8250_port *p)
 {
-	unsigned char old_dll, old_dlm, old_lcr;
+	unsigned char old_lcr;
+	unsigned int old_dl;
 	unsigned int id;
 
 	old_lcr = serial_inp(p, UART_LCR);
 	serial_outp(p, UART_LCR, UART_LCR_DLAB);
 
-	old_dll = serial_inp(p, UART_DLL);
-	old_dlm = serial_inp(p, UART_DLM);
+	old_dl = serial_dl_read(p);
 
-	serial_outp(p, UART_DLL, 0);
-	serial_outp(p, UART_DLM, 0);
+	serial_dl_write(p, 0);
+	id = serial_dl_read(p);
 
-	id = serial_inp(p, UART_DLL) | serial_inp(p, UART_DLM) << 8;
-
-	serial_outp(p, UART_DLL, old_dll);
-	serial_outp(p, UART_DLM, old_dlm);
+	serial_dl_write(p, old_dl);
 	serial_outp(p, UART_LCR, old_lcr);
 
 	return id;
@@ -1217,7 +1214,7 @@ static void autoconfig(struct uart_8250_
 	}
 #endif
 
-#ifdef CONFIG_SERIAL_8250_AU1X00
+#if defined (CONFIG_SERIAL_8250_AU1X00) || defined (CONFIG_SERIAL_8250_RT288X)
 	/* if access method is AU, it is a 16550 with a quirk */
 	if (up->port.type == PORT_16550A && up->port.iotype == UPIO_AU)
 		up->bugs |= UART_BUG_NOMSR;
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -266,6 +266,14 @@ config SERIAL_8250_AU1X00
 	  say Y to this option. The driver can handle up to 4 serial ports,
 	  depending on the SOC. If unsure, say N.
 
+config SERIAL_8250_RT288X
+	bool "Ralink RT288x/RT305x serial port support"
+	depends on SERIAL_8250 != n && (SOC_RT288X || SOC_RT305X)
+	help
+	  If you have a Ralink RT288x/RT305x SoC based board and want to use the 
+	  serial port, say Y to this option. The driver can handle up to 2 serial 
+	  ports. If unsure, say N.
+
 config SERIAL_8250_RM9K
 	bool "Support for MIPS RM9xxx integrated serial port"
 	depends on SERIAL_8250 != n && SERIAL_RM9000
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -281,7 +281,7 @@ struct uart_port {
 #define UPIO_HUB6		(1)
 #define UPIO_MEM		(2)
 #define UPIO_MEM32		(3)
-#define UPIO_AU			(4)			/* Au1x00 type IO */
+#define UPIO_AU			(4)			/* Au1x00 and RT288x type IO */
 #define UPIO_TSI		(5)			/* Tsi108/109 type IO */
 #define UPIO_DWAPB		(6)			/* DesignWare APB UART */
 #define UPIO_RM9000		(7)			/* RM9000 type IO */