MLK-21073 usb: cdns3: core: fix the oops when the interrupt occurs during suspend

When the interrupt occurs during the USB is entering suspend, the
cdns->lpm flag may not be updated well, the below oops may occur.
We treat above interrupt as wakeup interrupt, it should be handled
after lpm flag is set.

irq 120: nobody cared (try booting with the "irqpoll" option)
CPU: 0 PID: 107 Comm: kworker/0:1 Tainted: G           O    4.14.78 #1
Hardware name: Freescale i.MX8QM MEK (DT)
Workqueue: pm pm_runtime_work
Call trace:
[<ffff000008083230>] el1_irq+0xb0/0x124
[<ffff000009028fcc>] _raw_spin_unlock_irqrestore+0x18/0x48
[<ffff000008147a6c>] __irq_put_desc_unlock+0x1c/0x44
[<ffff000008149e4c>] enable_irq+0x54/0x90
[<ffff0000089cb08c>] cdns3_enter_suspend+0x30c/0x3ac
[<ffff0000089cb274>] cdns3_runtime_suspend+0x40/0x78
[<ffff000008796cd8>] pm_generic_runtime_suspend+0x28/0x48
[<ffff0000087a7400>] genpd_runtime_suspend+0x90/0x21c
[<ffff00000879a14c>] __rpm_callback+0x130/0x264
[<ffff00000879a2a4>] rpm_callback+0x24/0x78
[<ffff000008798ec8>] rpm_suspend+0x10c/0x668
[<ffff0000087996b4>] rpm_idle+0x1c0/0x390
[<ffff00000879aa6c>] pm_runtime_work+0x94/0xe0
[<ffff0000080fac88>] process_one_work+0x140/0x3f8
[<ffff0000080fb078>] worker_thread+0x138/0x3e4
[<ffff0000081014e0>] kthread+0x104/0x130
[<ffff00000808552c>] ret_from_fork+0x10/0x18

Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Arulpandiyan Vadivel <arulpandiyan_vadivel@mentor.com>
Signed-off-by: Shrikant Bobade <Shrikant_Bobade@mentor.com>
(cherry picked from commit e9f0c22de405d2e7f9698e67fbebde1e5aa37fdc)

diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
index db20506..b8a183f 100644 (file)
--- a/drivers/usb/cdns3/core.c
+++ b/drivers/usb/cdns3/core.c
@@ -704,10 +704,18 @@ static void cdns3_enter_suspend(struct cdns3 *cdns, bool suspend, bool wakeup)
        u32 value;
        int timeout_us = 100000;
 
-       if (cdns->role != CDNS3_ROLE_HOST)
+       if (cdns->role == CDNS3_ROLE_GADGET) {
+               if (suspend) {
+                       /* When at device mode, set controller at reset mode */
+                       value = readl(cdns->none_core_regs + USB3_CORE_CTRL1);
+                       value |= ALL_SW_RESET;
+                       writel(value, cdns->none_core_regs + USB3_CORE_CTRL1);
+               }
+               return;
+       } else if (cdns->role == CDNS3_ROLE_END) {
                return;
+       }
 
-       disable_irq(cdns->irq);
        if (suspend) {
                if (cdns3_role(cdns)->suspend)
                        cdns3_role(cdns)->suspend(cdns, wakeup);
@@ -823,6 +831,14 @@ static void cdns3_enter_suspend(struct cdns3 *cdns, bool suspend, bool wakeup)
                if (timeout_us <= 0)
                        dev_err(cdns->dev, "wait xhci_power_on_ready timeout\n");
        }
+}
+
+static void cdns3_controller_suspend(struct cdns3 *cdns, bool wakeup)
+{
+       disable_irq(cdns->irq);
+       cdns3_enter_suspend(cdns, true, wakeup);
+       usb_phy_set_suspend(cdns->usbphy, 1);
+       cdns->in_lpm = true;
        enable_irq(cdns->irq);
 }
 
@@ -831,29 +847,17 @@ static int cdns3_suspend(struct device *dev)
 {
        struct cdns3 *cdns = dev_get_drvdata(dev);
        bool wakeup = device_may_wakeup(dev);
-       u32 value;
 
        dev_dbg(dev, "at %s\n", __func__);
 
        if (pm_runtime_status_suspended(dev))
                pm_runtime_resume(dev);
 
-       if (cdns->role == CDNS3_ROLE_HOST)
-               cdns3_enter_suspend(cdns, true, wakeup);
-       else if (cdns->role == CDNS3_ROLE_GADGET) {
-               /* When at device mode, always set controller at reset mode */
-               value = readl(cdns->none_core_regs + USB3_CORE_CTRL1);
-               value |= ALL_SW_RESET;
-               writel(value, cdns->none_core_regs + USB3_CORE_CTRL1);
-       }
-
+       cdns3_controller_suspend(cdns, wakeup);
+       cdns3_disable_unprepare_clks(dev);
        if (wakeup)
                enable_irq_wake(cdns->irq);
 
-       usb_phy_set_suspend(cdns->usbphy, 1);
-       cdns3_disable_unprepare_clks(dev);
-       cdns->in_lpm = true;
-
        return 0;
 }
 
@@ -929,10 +933,8 @@ static int cdns3_runtime_suspend(struct device *dev)
                return 0;
        }
 
-       cdns3_enter_suspend(cdns, true, true);
-       usb_phy_set_suspend(cdns->usbphy, 1);
+       cdns3_controller_suspend(cdns, true);
        cdns3_disable_unprepare_clks(dev);
-       cdns->in_lpm = true;
 
        dev_dbg(dev, "at the end of %s\n", __func__);