usb: chipidea: usbmisc: add power lost check for imx7d

imx7d can shutdown domain power supply if none of peripheral in this
domain is registered as wakeup source, this patch add related codes to
check if power is lost.

Signed-off-by: Li Jun <jun.li@nxp.com>
Link: https://lore.kernel.org/r/20221013151442.3262951-8-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/chipidea/usbmisc_imx.c b/drivers/usb/chipidea/usbmisc_imx.c
index 7bfbfc8..cc17dcd 100644 (file)
--- a/drivers/usb/chipidea/usbmisc_imx.c
+++ b/drivers/usb/chipidea/usbmisc_imx.c
@@ -939,6 +939,25 @@ static int usbmisc_imx7ulp_init(struct imx_usbmisc_data *data)
        return 0;
 }
 
+static int usbmisc_imx7d_power_lost_check(struct imx_usbmisc_data *data)
+{
+       struct imx_usbmisc *usbmisc = dev_get_drvdata(data->dev);
+       unsigned long flags;
+       u32 val;
+
+       spin_lock_irqsave(&usbmisc->lock, flags);
+       val = readl(usbmisc->base);
+       spin_unlock_irqrestore(&usbmisc->lock, flags);
+       /*
+        * Here use a power on reset value to judge
+        * if the controller experienced a power lost
+        */
+       if (val == 0x30001000)
+               return 1;
+       else
+               return 0;
+}
+
 static int usbmisc_imx6sx_power_lost_check(struct imx_usbmisc_data *data)
 {
        struct imx_usbmisc *usbmisc = dev_get_drvdata(data->dev);
@@ -998,6 +1017,7 @@ static const struct usbmisc_ops imx7d_usbmisc_ops = {
        .init = usbmisc_imx7d_init,
        .set_wakeup = usbmisc_imx7d_set_wakeup,
        .charger_detection = imx7d_charger_detection,
+       .power_lost_check = usbmisc_imx7d_power_lost_check,
 };
 
 static const struct usbmisc_ops imx7ulp_usbmisc_ops = {