1 files changed, 19 insertions, 4 deletions

diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index 19805a7de06c..e10a02df6e1d 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -36,7 +36,13 @@
 #define UART_OMAP_NO_EMPTY_FIFO_READ_IP_REV     0x52
 #define UART_OMAP_WER           0x17    /* Wake-up enable register */
 
-#define DEFAULT_TIMEOUT (5 * HZ)
+/*
+ * NOTE: By default the serial timeout is disabled as it causes lost characters
+ * over the serial ports. This means that the UART clocks will stay on until
+ * disabled via sysfs. This also causes that any deeper omap sleep states are
+ * blocked. 
+ */
+#define DEFAULT_TIMEOUT 0
 
 struct omap_uart_state {
         int num;
@@ -125,6 +131,13 @@ static struct plat_serial8250_port serial_platform_data3[] = {
         }
 };
 #endif
+static inline unsigned int __serial_read_reg(struct uart_port *up,
+                                           int offset)
+{
+        offset <<= up->regshift;
+        return (unsigned int)__raw_readb(up->membase + offset);
+}
+
 static inline unsigned int serial_read_reg(struct plat_serial8250_port *up,
                                            int offset)
 {
@@ -415,7 +428,8 @@ static void omap_uart_idle_init(struct omap_uart_state *uart)
         uart->timeout = DEFAULT_TIMEOUT;
         setup_timer(&uart->timer, omap_uart_idle_timer,
                     (unsigned long) uart);
-        mod_timer(&uart->timer, jiffies + uart->timeout);
+        if (uart->timeout)
+                mod_timer(&uart->timer, jiffies + uart->timeout);
         omap_uart_smart_idle_enable(uart, 0);
 
         if (cpu_is_omap34xx()) {
@@ -583,11 +597,12 @@ static unsigned int serial_in_override(struct uart_port *up, int offset)
 {
         if (UART_RX == offset) {
                 unsigned int lsr;
-                lsr = serial_read_reg(omap_uart[up->line].p, UART_LSR);
+                lsr = __serial_read_reg(up, UART_LSR);
                 if (!(lsr & UART_LSR_DR))
                         return -EPERM;
         }
-        return serial_read_reg(omap_uart[up->line].p, offset);
+
+        return __serial_read_reg(up, offset);
 }
 
 void __init omap_serial_early_init(void)