Re: [PATCH] usb: chipidea: udc: clear vbus_active flag in udc_stop
From: Peter Chen
Date: Tue Oct 20 2015 - 02:29:28 EST
On Tue, Oct 20, 2015 at 03:09:02PM +0900, Jiada Wang wrote:
> Hi
>
> On 10/20/2015 03:01 PM, Peter Chen wrote:
> >On Tue, Oct 20, 2015 at 11:29:18AM +0900, Jiada Wang wrote:
> >>Currently in udc_stop, if vbus_active flag is true, all USB activities
> >>will be stopped, but vbus_active flag is still left to be true,
> >>this causes issue, when afterwards driver tries to connect gadget
> >>device to host, But due to the uncleared vbus_active, some necessary
> >>setup steps are skipped.
> >>
> >>This patch clears vbus_active flag in udc_stop callback.
> >>
> >>Signed-off-by: Jiada Wang <jiada_wang@xxxxxxxxxx>
> >>---
> >> drivers/usb/chipidea/udc.c | 1 +
> >> 1 file changed, 1 insertion(+)
> >>
> >>diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
> >>index 8223fe7..b9ac228 100644
> >>--- a/drivers/usb/chipidea/udc.c
> >>+++ b/drivers/usb/chipidea/udc.c
> >>@@ -1762,6 +1762,7 @@ static int ci_udc_stop(struct usb_gadget *gadget)
> >> spin_lock_irqsave(&ci->lock, flags);
> >>
> >> if (ci->vbus_active) {
> >>+ ci->vbus_active = 0;
> >> hw_device_state(ci, 0);
> >> if (ci->platdata->notify_event)
> >> ci->platdata->notify_event(ci,
> >>--
> >>2.4.5
> >>
> >
> >This flag will be handled by vbus interrupt, would you please explain
> >more what problem you have met?
> the actual issue I had is,
> build kernel with USB_OTG_FSM enabled,
> keep usb cable plugged,
> load/unload USB gadget module (for example I tried g_zero or g_serial),
> after unload gadget module once, then the status of vbus_active is not
> correct,
> this causes host machine failed to detect gadget device when later
> gadget device module is loaded again.
>
>
ci->vbus_active is only used at non-fsm mode, would you please try below
fix?
usb: chipidea: otg: gadget module load and unload support
This patch is to support load and unload gadget driver in full OTG mode.
Acked-by: Peter Chen <peter.chen@xxxxxxxxxxxxx>
Signed-off-by: Li Jun <jun.li@xxxxxxxxxxxxx>
---
drivers/usb/chipidea/udc.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
index e19d8b8..67cfa04 100644
--- a/drivers/usb/chipidea/udc.c
+++ b/drivers/usb/chipidea/udc.c
@@ -1755,6 +1755,22 @@ static int ci_udc_start(struct usb_gadget *gadget,
return retval;
}
+static void ci_udc_stop_for_otg_fsm(struct ci_hdrc *ci)
+{
+ if (!ci_otg_is_fsm_mode(ci))
+ return;
+
+ mutex_lock(&ci->fsm.lock);
+ if (ci->fsm.otg->state == OTG_STATE_A_PERIPHERAL) {
+ ci->fsm.a_bidl_adis_tmout = 1;
+ ci_hdrc_otg_fsm_start(ci);
+ } else if (ci->fsm.otg->state == OTG_STATE_B_PERIPHERAL) {
+ ci->fsm.protocol = PROTO_UNDEF;
+ ci->fsm.otg->state = OTG_STATE_UNDEFINED;
+ }
+ mutex_unlock(&ci->fsm.lock);
+}
+
/**
* ci_udc_stop: unregister a gadget driver
*/
@@ -1779,6 +1795,7 @@ static int ci_udc_stop(struct usb_gadget *gadget)
ci->driver = NULL;
spin_unlock_irqrestore(&ci->lock, flags);
+ ci_udc_stop_for_otg_fsm(ci);
return 0;
}
--
1.9.1
--
Best Regards,
Peter Chen
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