Hello,
On 2014-11-14 23:09, Paul Zimmerman wrote:
From: Paul Zimmerman
Sent: Friday, November 14, 2014 1:21 PM
From: linux-usb-owner@xxxxxxxxxxxxxxx [mailto:linux-usb-owner@xxxxxxxxxxxxxxx] On Behalf Of Felipe Balbi
Sent: Friday, November 14, 2014 11:05 AM
On Fri, Nov 14, 2014 at 07:01:37PM +0000, Paul Zimmerman wrote:
-----Original Message-----
From: Marek Szyprowski [mailto:m.szyprowski@xxxxxxxxxxx]
Sent: Friday, November 14, 2014 4:20 AM
This patch adds a call to s3c_hsotg_disconnect() from 'end session'
interrupt (GOTGINT_SES_END_DET) to correctly notify gadget subsystem
about unplugged usb cable. DISCONNINT interrupt cannot be used for this
purpose, because it is asserted only in host mode.
To avoid reporting disconnect event more than once, a disconnect call has
been moved from USB_REQ_SET_ADDRESS handling function to SESSREQINT
interrupt. This way driver ensures that disconnect event is reported
either when usb cable is unplugged or every time the host starts a new
session.
Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
---
drivers/usb/dwc2/core.h | 1 +
drivers/usb/dwc2/gadget.c | 13 +++++++++++--
2 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index 55c90c53f2d6..78b9090ebf71 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -210,6 +210,7 @@ struct s3c_hsotg {
u8 ctrl_buff[8];
struct usb_gadget gadget;
+ unsigned int session:1;
unsigned int setup;
unsigned long last_rst;
struct s3c_hsotg_ep *eps;
diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index fcd2bb55ccca..c7f68dc1cf6b 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -1029,7 +1029,6 @@ static int s3c_hsotg_process_req_feature(struct s3c_hsotg *hsotg,
}
static void s3c_hsotg_enqueue_setup(struct s3c_hsotg *hsotg);
-static void s3c_hsotg_disconnect(struct s3c_hsotg *hsotg);
/**
* s3c_hsotg_stall_ep0 - stall ep0
@@ -1107,7 +1106,6 @@ static void s3c_hsotg_process_control(struct s3c_hsotg *hsotg,
if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
switch (ctrl->bRequest) {
case USB_REQ_SET_ADDRESS:
- s3c_hsotg_disconnect(hsotg);
dcfg = readl(hsotg->regs + DCFG);
dcfg &= ~DCFG_DEVADDR_MASK;
dcfg |= (le16_to_cpu(ctrl->wValue) <<
@@ -2031,6 +2029,10 @@ static void s3c_hsotg_disconnect(struct s3c_hsotg *hsotg)
{
unsigned ep;
+ if (!hsotg->session)
+ return;
+
+ hsotg->session = 0;
for (ep = 0; ep < hsotg->num_of_eps; ep++)
kill_all_requests(hsotg, &hsotg->eps[ep], -ESHUTDOWN, true);
@@ -2290,11 +2292,18 @@ irq_retry:
dev_info(hsotg->dev, "OTGInt: %08x\n", otgint);
writel(otgint, hsotg->regs + GOTGINT);
+
+ if (otgint & GOTGINT_SES_END_DET) {
+ s3c_hsotg_disconnect(hsotg);
I think you should clear hsotg->session here, shouldn't you?
Otherwise I think s3c_hsotg_disconnect() will be called twice, once
here and once when the next GINTSTS_SESSREQINT comes.
the best way to avoid that would be fiddle with hsotg->session inside
s3c_hsotg_disconnect() only.
Whoops, I just noticed that hsotg->session *is* cleared inside of
s3c_hsotg_disconnect(). So I think the patch is good as-is.
Acked-by: Paul Zimmerman <paulz@xxxxxxxxxxxx>
I'm having second thoughts about this. Currently, the
GINTSTS_SESSREQINT interrupt in the gadget does nothing except print
a debug message. So I'm not sure that all versions of the controller
actually assert this interrupt when a connection is made. If they
don't, then this patch would break the disconnect handling, since
hsotg->session would never get set.
In particular, I'm thinking that a core which is synthesized without
SRP support may not implement the GINTSTS_SESSREQINT interrupt. The
databook seems to imply that:
"SessReqInt: In Device mode, this interrupt is asserted when the
utmisrp_bvalid signal goes high."
And in the section which describes the utmisrp_bvalid signal, there is
a note that says:
"This interface is present only when parameter OTG_MODE specifies an
SRP-capable configuration."
So Marek, can you try moving the line which sets hsotg->session = 1
into s3c_hsotg_irq_enumdone() instead? Then we will be sure it gets set
to one after a connect. Probably it should be renamed from 'session'
to 'connect' in that case.
Well... ok, but this will work exactly the same way as v3, which you were
not keen of. I think the best way will be to keep it set both in SESSREQINT
and enumdone, I will send a patch in a few minutes.
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
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