[RFC PATCH] usb: musb: Fix external abort in musb_remove

From: Merlijn Wajer
Date: Thu Mar 08 2018 - 04:32:14 EST


This fixes an oops on unbind / module unload. The fix is similar to the
one in this commit: 0c3aae9bd59978fb8c3557d7883380bef0f2cfa1 (USB: musb:
fix late external abort on suspend), which only fixes the issue for
musb_suspend.

musb_remove function now also flushes any work and also calls
musb_platform_exit before disabling runtime pm.

Signed-off-by: Merlijn Wajer <merlijn@xxxxxxxxxx>
---

If I understand commit 0c3aae9bd59978fb8c3557d7883380bef0f2cfa1 correctly,
this patch should also be backported to 4.9 (and newer kernels).

I have verified that this works on the Nokia N900, RX-51. The problem did not
occur on the Motorola Droid 4, but I have yet to test if this patch causes
issues there.

drivers/usb/musb/musb_core.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index e2e95071328a..4fb0f345c04e 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -2472,13 +2472,19 @@ static int musb_remove(struct platform_device *pdev)
musb_platform_disable(musb);
spin_lock_irqsave(&musb->lock, flags);
musb_disable_interrupts(musb);
+
+ musb->flush_irq_work = true;
+ while (flush_delayed_work(&musb->irq_work))
+ ;
+ musb->flush_irq_work = false;
+
musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
+ musb_platform_exit(musb);
spin_unlock_irqrestore(&musb->lock, flags);

pm_runtime_dont_use_autosuspend(musb->controller);
pm_runtime_put_sync(musb->controller);
pm_runtime_disable(musb->controller);
- musb_platform_exit(musb);
musb_phy_callback = NULL;
if (musb->dma_controller)
musb_dma_controller_destroy(musb->dma_controller);
--
2.16.2