On Wed, Mar 18, 2015 at 01:36:13PM +0800, Peter Chen wrote:
> On Tue, Mar 17, 2015 at 10:37:47PM +0800, Li Jun wrote:
> > Adds HNP polling timer when transits to host state, the OTG status request
> > will be sent to peripheral after timeout, if host request flag is set, it will
> > switch to peripheral state, otherwise it will repeat HNP polling every 1.5s and
> > maintain the current session.
> >
> > Signed-off-by: Li Jun <jun.li@xxxxxxxxxxxxx>
> > ---
> > drivers/usb/common/usb-otg-fsm.c | 84 ++++++++++++++++++++++++++++++++++++++
> > include/linux/usb/otg-fsm.h | 13 ++++++
> > 2 files changed, 97 insertions(+)
> >
> > diff --git a/drivers/usb/common/usb-otg-fsm.c b/drivers/usb/common/usb-otg-fsm.c
> > index 61d538a..1a1b5f4 100644
> > --- a/drivers/usb/common/usb-otg-fsm.c
> > +++ b/drivers/usb/common/usb-otg-fsm.c
> > +static void otg_hnp_polling_work(struct work_struct *work)
> > +{
> > + struct otg_fsm *fsm = container_of(to_delayed_work(work),
> > + struct otg_fsm, hnp_polling_work);
> > + struct usb_device *udev;
> > + u8 host_req_flag;
> > + enum usb_otg_state state = fsm->otg->state;
> > + int retval;
> > +
> > + if (state != OTG_STATE_A_HOST && state != OTG_STATE_B_HOST)
> > + return;
> > +
> > + udev = usb_hub_find_child(fsm->otg->host->root_hub, 1);
> > + if (!udev) {
> > + dev_err(fsm->otg->host->controller,
> > + "no usb dev connected, can't start HNP polling\n");
> > + return;
> > + }
> > +
> > + /* Get host request flag from connected USB device */
> > + retval = usb_control_msg(udev,
> > + usb_rcvctrlpipe(udev, 0),
> > + USB_REQ_GET_STATUS,
> > + USB_DIR_IN | USB_RECIP_DEVICE,
> > + 0,
> > + OTG_STS_SELECTOR,
> > + &host_req_flag,
> > + 1,
> > + USB_CTRL_GET_TIMEOUT);
> > + if (retval != 1) {
> > + dev_err(&udev->dev, "Get one byte OTG status failed\n");
> > + return;
> > + }
>
> If I plug usb thumb device, it will print above message, any ways to
> hide it for non hnp-polling featured device?
>
> Others are ok
>
> Peter
>
This is known to me, I plan to enhance this in my next step, for this patchset,
which can be prevented by change of something like below:
diff --git a/drivers/usb/common/usb-otg-fsm.c b/drivers/usb/common/usb-otg-fsm.c
index 1a1b5f4..20906f6 100644
--- a/drivers/usb/common/usb-otg-fsm.c
+++ b/drivers/usb/common/usb-otg-fsm.c
@@ -197,9 +197,30 @@ static void otg_hnp_polling_work(struct work_struct *work)
static void otg_start_hnp_polling(struct otg_fsm *fsm)
{
- INIT_DELAYED_WORK(&fsm->hnp_polling_work, otg_hnp_polling_work);
- schedule_delayed_work(&fsm->hnp_polling_work,
+ struct usb_device *udev;
+ struct usb_otg_descriptor *desc = NULL;
+
+ udev = usb_hub_find_child(fsm->otg->host->root_hub, 1);
+ if (!udev) {
+ dev_err(fsm->otg->host->controller,
+ "no usb dev connected, can't start HNP polling\n");
+ return;
+ }
+
+ if (__usb_get_extra_descriptor(udev->rawdescriptors[0],
+ le16_to_cpu(udev->config[0].desc.wTotalLength),
+ USB_DT_OTG, (void **) &desc) == 0) {
+ if (desc->bmAttributes & USB_OTG_HNP) {
+ INIT_DELAYED_WORK(&fsm->hnp_polling_work,
+ otg_hnp_polling_work);
+ schedule_delayed_work(&fsm->hnp_polling_work,
+ msecs_to_jiffies(T_HOST_REQ_POLL));
+ } else {
+ dev_info(&udev->dev, "OTG device w/o HNP capable\n");
+ }
+ } else {
+ dev_info(&udev->dev, "Non-OTG device\n");
+ }
}
Idea is to check if the connected device is a HNP capable OTG(even V2.0)device,
maybe the better way is to use some flag which can be set while enumeration
of OTG device(again existing bus->b_hnp_enable is not accurate for this purpose),
Li Jun
> >
> > +
> > + if (host_req_flag == 0) {
> > + /* Continue HNP polling */
> > + schedule_delayed_work(&fsm->hnp_polling_work,
> > + msecs_to_jiffies(T_HOST_REQ_POLL));
> > + return;
> > + } else if (host_req_flag != HOST_REQUEST_FLAG) {
> > + dev_err(&udev->dev, "host request flag %d is invalid\n",
> > + host_req_flag);
> > + return;
> > + }
> > +
> > + /* Host request flag is set */
> > + if (state == OTG_STATE_A_HOST) {
> > + /* Set b_hnp_enable */
> > + if (!fsm->otg->host->b_hnp_enable) {
> > + retval = usb_control_msg(udev,
> > + usb_sndctrlpipe(udev, 0),
> > + USB_REQ_SET_FEATURE, 0,
> > + USB_DEVICE_B_HNP_ENABLE,
> > + 0, NULL, 0,
> > + USB_CTRL_SET_TIMEOUT);
> > + if (retval < 0) {
> > + dev_err(&udev->dev,
> > + "can't enable HNP %d\n", retval);
> > + return;
> > + }
> > + fsm->otg->host->b_hnp_enable = 1;
> > + }
> > +
> > + fsm->a_bus_req = 0;
> > + } else if (state == OTG_STATE_B_HOST) {
> > + fsm->b_bus_req = 0;
> > + }
> > +
> > + otg_statemachine(fsm);
> > +}
> > +
> > +static void otg_start_hnp_polling(struct otg_fsm *fsm)
> > +{
> > + INIT_DELAYED_WORK(&fsm->hnp_polling_work, otg_hnp_polling_work);
> > + schedule_delayed_work(&fsm->hnp_polling_work,
> > + msecs_to_jiffies(T_HOST_REQ_POLL));
> > +}
> > +
> > /* Called when entering a state */
> > static int otg_set_state(struct otg_fsm *fsm, enum usb_otg_state new_state)
> > {
> > @@ -169,6 +251,7 @@ static int otg_set_state(struct otg_fsm *fsm, enum usb_otg_state new_state)
> > otg_set_protocol(fsm, PROTO_HOST);
> > usb_bus_start_enum(fsm->otg->host,
> > fsm->otg->host->otg_port);
> > + otg_start_hnp_polling(fsm);
> > break;
> > case OTG_STATE_A_IDLE:
> > otg_drv_vbus(fsm, 0);
> > @@ -203,6 +286,7 @@ static int otg_set_state(struct otg_fsm *fsm, enum usb_otg_state new_state)
> > */
> > if (!fsm->a_bus_req || fsm->a_suspend_req_inf)
> > otg_add_timer(fsm, A_WAIT_ENUM);
> > + otg_start_hnp_polling(fsm);
> > break;
> > case OTG_STATE_A_SUSPEND:
> > otg_drv_vbus(fsm, 1);
> > diff --git a/include/linux/usb/otg-fsm.h b/include/linux/usb/otg-fsm.h
> > index f728f18..2bea252 100644
> > --- a/include/linux/usb/otg-fsm.h
> > +++ b/include/linux/usb/otg-fsm.h
> > @@ -40,6 +40,18 @@
> > #define PROTO_HOST (1)
> > #define PROTO_GADGET (2)
> >
> > +#define OTG_STS_SELECTOR 0xF000 /* OTG status selector, according to
> > + * OTG and EH 2.0 Chapter 6.2.3
> > + * Table:6-4
> > + */
> > +
> > +#define HOST_REQUEST_FLAG 1 /* Host request flag, according to
> > + * OTG and EH 2.0 Charpter 6.2.3
> > + * Table:6-5
> > + */
> > +
> > +#define T_HOST_REQ_POLL (1500) /* 1500ms, HNP polling interval */
> > +
> > enum otg_fsm_timer {
> > /* Standard OTG timers */
> > A_WAIT_VRISE,
> > @@ -119,6 +131,7 @@ struct otg_fsm {
> > /* Current usb protocol used: 0:undefine; 1:host; 2:client */
> > int protocol;
> > struct mutex lock;
> > + struct delayed_work hnp_polling_work;
> > };
> >
> > struct otg_fsm_ops {
> > --
> > 1.7.9.5
> >
>
> --
>
> Best Regards,
> Peter Chen
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