serial: imx: add imx_poll_init()

For the console poll usage, .poll_init() will perform deeper hardware
initialization to ensure the serial port is always active.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Huang Shijie <b32955@freescale.com>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 8d61aa98b932cf82925fcf98cc8587552d240346..062e7614c9861a342de68e3df08489a045fb77c1 100644 (file)
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1455,6 +1455,41 @@ imx_verify_port(struct uart_port *port, struct serial_struct *ser)
 }
 
 #if defined(CONFIG_CONSOLE_POLL)
+
+static int imx_poll_init(struct uart_port *port)
+{
+       struct imx_port *sport = (struct imx_port *)port;
+       unsigned long flags;
+       unsigned long temp;
+       int retval;
+
+       retval = clk_prepare_enable(sport->clk_ipg);
+       if (retval)
+               return retval;
+       retval = clk_prepare_enable(sport->clk_per);
+       if (retval)
+               clk_disable_unprepare(sport->clk_ipg);
+
+       imx_setup_ufcr(sport, 0);
+
+       spin_lock_irqsave(&sport->port.lock, flags);
+
+       temp = readl(sport->port.membase + UCR1);
+       if (is_imx1_uart(sport))
+               temp |= IMX1_UCR1_UARTCLKEN;
+       temp |= UCR1_UARTEN | UCR1_RRDYEN;
+       temp &= ~(UCR1_TXMPTYEN | UCR1_RTSDEN);
+       writel(temp, sport->port.membase + UCR1);
+
+       temp = readl(sport->port.membase + UCR2);
+       temp |= UCR2_RXEN;
+       writel(temp, sport->port.membase + UCR2);
+
+       spin_unlock_irqrestore(&sport->port.lock, flags);
+
+       return 0;
+}
+
 static int imx_poll_get_char(struct uart_port *port)
 {
        if (!(readl_relaxed(port->membase + USR2) & USR2_RDR))
@@ -1499,6 +1534,7 @@ static struct uart_ops imx_pops = {
        .config_port    = imx_config_port,
        .verify_port    = imx_verify_port,
 #if defined(CONFIG_CONSOLE_POLL)
+       .poll_init      = imx_poll_init,
        .poll_get_char  = imx_poll_get_char,
        .poll_put_char  = imx_poll_put_char,
 #endif