diff options
| author | Alan Stern <stern@rowland.harvard.edu> | 2021-05-20 16:22:06 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-06-04 13:52:09 +0200 |
| commit | 87191ca9f90244d4e003fbe5c77390b5e585a5ef (patch) | |
| tree | 0bc3c7d850610a57294f8c3512de9345eee3625a /drivers/usb/gadget/udc | |
| parent | b42e8090ba93526d6063108b25e5fc0f11f58770 (diff) | |
USB: UDC: Implement udc_async_callbacks in net2272
This patch adds a udc_async_callbacks handler to the net2272 UDC
driver, which will prevent a theoretical race during gadget unbinding.
The net2272 driver is sufficiently complicated that I didn't want to
mess around with IRQ settings. Instead, the patch simply adds a new
flag to control async callbacks, and checks the flag before issuing
any of them.
Acked-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20210520202206.GF1216852@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/gadget/udc')
| -rw-r--r-- | drivers/usb/gadget/udc/net2272.c | 41 | ||||
| -rw-r--r-- | drivers/usb/gadget/udc/net2272.h | 1 |
2 files changed, 28 insertions, 14 deletions
diff --git a/drivers/usb/gadget/udc/net2272.c b/drivers/usb/gadget/udc/net2272.c index 89f479b78d80..7c38057dcb4a 100644 --- a/drivers/usb/gadget/udc/net2272.c +++ b/drivers/usb/gadget/udc/net2272.c @@ -1150,6 +1150,7 @@ net2272_pullup(struct usb_gadget *_gadget, int is_on) static int net2272_start(struct usb_gadget *_gadget, struct usb_gadget_driver *driver); static int net2272_stop(struct usb_gadget *_gadget); +static void net2272_async_callbacks(struct usb_gadget *_gadget, bool enable); static const struct usb_gadget_ops net2272_ops = { .get_frame = net2272_get_frame, @@ -1158,6 +1159,7 @@ static const struct usb_gadget_ops net2272_ops = { .pullup = net2272_pullup, .udc_start = net2272_start, .udc_stop = net2272_stop, + .udc_async_callbacks = net2272_async_callbacks, }; /*---------------------------------------------------------------------------*/ @@ -1476,7 +1478,7 @@ stop_activity(struct net2272 *dev, struct usb_gadget_driver *driver) net2272_dequeue_all(&dev->ep[i]); /* report disconnect; the driver is already quiesced */ - if (driver) { + if (dev->async_callbacks && driver) { spin_unlock(&dev->lock); driver->disconnect(&dev->gadget); spin_lock(&dev->lock); @@ -1501,6 +1503,15 @@ static int net2272_stop(struct usb_gadget *_gadget) return 0; } +static void net2272_async_callbacks(struct usb_gadget *_gadget, bool enable) +{ + struct net2272 *dev = container_of(_gadget, struct net2272, gadget); + + spin_lock_irq(&dev->lock); + dev->async_callbacks = enable; + spin_unlock_irq(&dev->lock); +} + /*---------------------------------------------------------------------------*/ /* handle ep-a/ep-b dma completions */ static void @@ -1910,9 +1921,11 @@ net2272_handle_stat0_irqs(struct net2272 *dev, u8 stat) u.r.bRequestType, u.r.bRequest, u.r.wValue, u.r.wIndex, net2272_ep_read(ep, EP_CFG)); - spin_unlock(&dev->lock); - tmp = dev->driver->setup(&dev->gadget, &u.r); - spin_lock(&dev->lock); + if (dev->async_callbacks) { + spin_unlock(&dev->lock); + tmp = dev->driver->setup(&dev->gadget, &u.r); + spin_lock(&dev->lock); + } } /* stall ep0 on error */ @@ -1994,14 +2007,14 @@ net2272_handle_stat1_irqs(struct net2272 *dev, u8 stat) if (disconnect || reset) { stop_activity(dev, dev->driver); net2272_ep0_start(dev); - spin_unlock(&dev->lock); - if (reset) - usb_gadget_udc_reset - (&dev->gadget, dev->driver); - else - (dev->driver->disconnect) - (&dev->gadget); - spin_lock(&dev->lock); + if (dev->async_callbacks) { + spin_unlock(&dev->lock); + if (reset) + usb_gadget_udc_reset(&dev->gadget, dev->driver); + else + (dev->driver->disconnect)(&dev->gadget); + spin_lock(&dev->lock); + } return; } } @@ -2015,14 +2028,14 @@ net2272_handle_stat1_irqs(struct net2272 *dev, u8 stat) if (stat & tmp) { net2272_write(dev, IRQSTAT1, tmp); if (stat & (1 << SUSPEND_REQUEST_INTERRUPT)) { - if (dev->driver->suspend) + if (dev->async_callbacks && dev->driver->suspend) dev->driver->suspend(&dev->gadget); if (!enable_suspend) { stat &= ~(1 << SUSPEND_REQUEST_INTERRUPT); dev_dbg(dev->dev, "Suspend disabled, ignoring\n"); } } else { - if (dev->driver->resume) + if (dev->async_callbacks && dev->driver->resume) dev->driver->resume(&dev->gadget); } stat &= ~tmp; diff --git a/drivers/usb/gadget/udc/net2272.h b/drivers/usb/gadget/udc/net2272.h index c669308111c2..a9994f737588 100644 --- a/drivers/usb/gadget/udc/net2272.h +++ b/drivers/usb/gadget/udc/net2272.h @@ -442,6 +442,7 @@ struct net2272 { softconnect:1, wakeup:1, added:1, + async_callbacks:1, dma_eot_polarity:1, dma_dack_polarity:1, dma_dreq_polarity:1, |