* [PATCH] usb: dwc2: only prevent new request when power_down is possible
@ 2020-04-10 14:31 Fabrice Gasnier
2020-04-13 8:56 ` Minas Harutyunyan
0 siblings, 1 reply; 2+ messages in thread
From: Fabrice Gasnier @ 2020-04-10 14:31 UTC (permalink / raw)
To: hminas
Cc: gregkh, balbi, johnyoun, gregory.herrero, Grigor.Tovmasyan,
amelie.delaunay, linux-usb, linux-kernel, linux-stm32
When controller is suspended, registers mustn't be touched. This is not
the case when 'power_down' is set to none. In this case, power saving
routines are skipped.
This fixes a case where gadget driver (f_acm) gets opened (cat /dev/ttyGS0)
but the bus has been suspended by the host:
- configfs-gadget gadget: acm ttyGS0 can't notify serial state, -11
Fixes: 7ababa926c66 ("usb: dwc2: gadget: prevent new request submission during suspend")
Fixes: 88b02f2cb1e1 ("usb: dwc2: Add core state checking")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
---
drivers/usb/dwc2/gadget.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 92ed32e..45a8782 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -1375,7 +1375,8 @@ static int dwc2_hsotg_ep_queue(struct usb_ep *ep, struct usb_request *req,
req->zero, req->short_not_ok);
/* Prevent new request submission when controller is suspended */
- if (hs->lx_state != DWC2_L0) {
+ if (hs->params.power_down != DWC2_POWER_DOWN_PARAM_NONE &&
+ hs->lx_state != DWC2_L0) {
dev_dbg(hs->dev, "%s: submit request only in active state\n",
__func__);
return -EAGAIN;
--
2.7.4
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH] usb: dwc2: only prevent new request when power_down is possible
2020-04-10 14:31 [PATCH] usb: dwc2: only prevent new request when power_down is possible Fabrice Gasnier
@ 2020-04-13 8:56 ` Minas Harutyunyan
0 siblings, 0 replies; 2+ messages in thread
From: Minas Harutyunyan @ 2020-04-13 8:56 UTC (permalink / raw)
To: Fabrice Gasnier
Cc: gregkh, balbi, John Youn, gregory.herrero, Grigor.Tovmasyan,
amelie.delaunay, linux-usb, linux-kernel, linux-stm32
Hi,
On 4/10/2020 6:31 PM, Fabrice Gasnier wrote:
> When controller is suspended, registers mustn't be touched. This is not
> the case when 'power_down' is set to none. In this case, power saving
> routines are skipped.
If core in suspend mode even with any enabled power saving modes then
lx_state = DWC2_L2. If power_down != DWC2_POWER_DOWN_PARAM_NONE it
doesn't mean that core in suspend state (DWC2_L2) and declining request
is wrong. So, additional checking of params.power_dowm here is not correct.
>
> This fixes a case where gadget driver (f_acm) gets opened (cat /dev/ttyGS0)
> but the bus has been suspended by the host:
> - configfs-gadget gadget: acm ttyGS0 can't notify serial state, -11
>
> Fixes: 7ababa926c66 ("usb: dwc2: gadget: prevent new request submission during suspend")
> Fixes: 88b02f2cb1e1 ("usb: dwc2: Add core state checking")
>
> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
> ---
> drivers/usb/dwc2/gadget.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
> index 92ed32e..45a8782 100644
> --- a/drivers/usb/dwc2/gadget.c
> +++ b/drivers/usb/dwc2/gadget.c
> @@ -1375,7 +1375,8 @@ static int dwc2_hsotg_ep_queue(struct usb_ep *ep, struct usb_request *req,
> req->zero, req->short_not_ok);
>
> /* Prevent new request submission when controller is suspended */
> - if (hs->lx_state != DWC2_L0) {
> + if (hs->params.power_down != DWC2_POWER_DOWN_PARAM_NONE &&
> + hs->lx_state != DWC2_L0) {
> dev_dbg(hs->dev, "%s: submit request only in active state\n",
> __func__);
> return -EAGAIN;
>
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2020-04-13 8:57 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-04-10 14:31 [PATCH] usb: dwc2: only prevent new request when power_down is possible Fabrice Gasnier
2020-04-13 8:56 ` Minas Harutyunyan
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).