ARM: davinci: uncompress.h: bail out if uart not initialized

Bail out of UART access functions in uncompress.h if the uart
port is not setup. This will happen when booting from DT since
machine type matching does not work in this case. This may also
happen if a correct machine type is not setup by bootloader.

Signed-off-by: Sekhar Nori <nsekhar@ti.com>

diff --git a/arch/arm/mach-davinci/include/mach/uncompress.h b/arch/arm/mach-davinci/include/mach/uncompress.h
index 18cfd4977155b468970559945663e05a48bb2000..3a0ff905a69bb979618476eaaee4318941c0fd22 100644 (file)
--- a/arch/arm/mach-davinci/include/mach/uncompress.h
+++ b/arch/arm/mach-davinci/include/mach/uncompress.h
@@ -32,6 +32,9 @@ u32 *uart;
 /* PORT_16C550A, in polled non-fifo mode */
 static void putc(char c)
 {
+       if (!uart)
+               return;
+
        while (!(uart[UART_LSR] & UART_LSR_THRE))
                barrier();
        uart[UART_TX] = c;
@@ -39,6 +42,9 @@ static void putc(char c)
 
 static inline void flush(void)
 {
+       if (!uart)
+               return;
+
        while (!(uart[UART_LSR] & UART_LSR_THRE))
                barrier();
 }