According to the gadget.h, a "complete" function will always be called
with interrupts disabled. However, sometimes usbhsg_queue_pop() function
is called with interrupts enabled. So, this function should calls
local_irq_save() before this calls the usb_gadget_giveback_request().
Otherwise, there is possible to cause a spinlock suspected in a gadget
complete function.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda...@renesas.com>
---
drivers/usb/renesas_usbhs/mod_gadget.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/drivers/usb/renesas_usbhs/mod_gadget.c
b/drivers/usb/renesas_usbhs/mod_gadget.c
index e0384af..104bddf 100644
--- a/drivers/usb/renesas_usbhs/mod_gadget.c
+++ b/drivers/usb/renesas_usbhs/mod_gadget.c
@@ -126,11 +126,22 @@ static void usbhsg_queue_pop(struct usbhsg_uep *uep,
struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);
struct device *dev = usbhsg_gpriv_to_dev(gpriv);
+ unsigned long flags;
dev_dbg(dev, "pipe %d : queue pop\n", usbhs_pipe_number(pipe));
ureq->req.status = status;
+ /*
+ * According to the gadget.h, a "complete" function will always be
+ * called with interrupts disabled. However, sometimes this function
+ * is called with interrupts enabled. (e.g. complete a DMAC transfer or
+ * write data and done is set immediately when PIO.) So, this function
+ * should calls local_irq_save() before this calls the
+ * usb_gadget_giveback_request().
+ */
+ local_irq_save(flags);
usb_gadget_giveback_request(&uep->ep, &ureq->req);
+ local_irq_restore(flags);
}
static void usbhsg_queue_done(struct usbhs_priv *priv, struct usbhs_pkt *pkt)
--
1.7.9.5
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