8250: use callbacks to access UART_DLL/UART_DLM

[pandora-kernel.git] / drivers / tty / serial / 8250.c

diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c
index cff03e5..07cfec5 100644 (file)
--- a/drivers/tty/serial/8250.c
+++ b/drivers/tty/serial/8250.c
@@ -777,22 +777,16 @@ static int size_fifo(struct uart_8250_port *up)
  */
 static unsigned int autoconfig_read_divisor_id(struct uart_8250_port *p)
 {
-       unsigned char old_dll, old_dlm, old_lcr;
-       unsigned int id;
+       unsigned char old_lcr;
+       unsigned int id, old_dl;
 
        old_lcr = serial_inp(p, UART_LCR);
        serial_outp(p, UART_LCR, UART_LCR_CONF_MODE_A);
+       old_dl = serial_dl_read(p);
+       serial_dl_write(p, 0);
+       id = serial_dl_read(p);
+       serial_dl_write(p, old_dl);
 
-       old_dll = serial_inp(p, UART_DLL);
-       old_dlm = serial_inp(p, UART_DLM);
-
-       serial_outp(p, UART_DLL, 0);
-       serial_outp(p, UART_DLM, 0);
-
-       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_outp(p, UART_LCR, old_lcr);
 
        return id;
@@ -2701,6 +2695,10 @@ static void serial8250_config_port(struct uart_port *port, int flags)
        if (up->port.type == PORT_16550A && up->port.iotype == UPIO_AU)
                up->bugs |= UART_BUG_NOMSR;
 
+       /* HW bugs may trigger IRQ while IIR == NO_INT */
+       if (up->port.type == PORT_TEGRA)
+               up->bugs |= UART_BUG_NOMSR;
+
        if (up->port.type != PORT_UNKNOWN && flags & UART_CONFIG_IRQ)
                autoconfig_irq(up);