From: Grygorii Strashko <grygorii.stras...@ti.com>

If earlyprintk is enabled and current UART is console port the platform
code can mark it as RPM_ACTIVE to sync real IP state with PM Runtime and
avoid resuming of already active device, but now, driver initialization
will be performed in the wrong way:

        pm_runtime_enable(&pdev->dev);
    <-- PM runtime alowed (device state RPM_ACTIVE)
        if (omap_up_info->autosuspend_timeout == 0)
                omap_up_info->autosuspend_timeout = -1;
        device_init_wakeup(up->dev, true);
        pm_runtime_use_autosuspend(&pdev->dev);
        <-- update_autosuspend() will be called and it will disable device
        (device state RPM_SUSPENDED)
        pm_runtime_set_autosuspend_delay(&pdev->dev,
                        omap_up_info->autosuspend_timeout);
        <-- update_autosuspend() will be called which will re-enable device
        (device state RPM_ACTIVE), because autosuspend_timeout < 0

        pm_runtime_irq_safe(&pdev->dev);
        pm_runtime_get_sync(&pdev->dev);
        <-- will do nothing

Such behavior isn't expected by OMAP serial drivers and causes
unpredictable calls of serial_omap_runtime_suspend() and
serial_omap_runtime_resume().

Hence, fix it by allowing PM runtime only after all its parameters are
configured.

CC: Tony Lindgren <t...@atomide.com>
CC: Rajendra Nayak <rna...@ti.com>
CC: Felipe Balbi <ba...@ti.com>
CC: Kevin Hilman <khil...@linaro.org>

Signed-off-by: Grygorii Strashko <grygorii.stras...@ti.com>
---
 drivers/tty/serial/omap-serial.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index b6d1728..f39bf0c 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -1501,7 +1501,6 @@ static int serial_omap_probe(struct platform_device *pdev)
        INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
 
        platform_set_drvdata(pdev, up);
-       pm_runtime_enable(&pdev->dev);
        if (omap_up_info->autosuspend_timeout == 0)
                omap_up_info->autosuspend_timeout = -1;
        device_init_wakeup(up->dev, true);
@@ -1510,6 +1509,8 @@ static int serial_omap_probe(struct platform_device *pdev)
                        omap_up_info->autosuspend_timeout);
 
        pm_runtime_irq_safe(&pdev->dev);
+       pm_runtime_enable(&pdev->dev);
+
        pm_runtime_get_sync(&pdev->dev);
 
        omap_serial_fill_features_erratas(up);
-- 
1.7.9.5

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