| Message ID | 1436572068-10661-6-git-send-email-rojtberg@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
On Sat, Jul 11, 2015 at 01:47:45AM +0200, Pavel Rojtberg wrote: > From: "Pierre-Loup A. Griffais" <pgriffais@valvesoftware.com> > > Handle the "a new device is present" message properly by dynamically > creating the input device at this point in time. This requires a > workqueue as we are in interrupt context when we learn about this. > > Also properly disconnect any devices that we are told are removed. > > Signed-off-by: "Pierre-Loup A. Griffais" <pgriffais@valvesoftware.com> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Signed-off-by: Pavel Rojtberg <rojtberg@gmail.com> > --- > drivers/input/joystick/xpad.c | 43 +++++++++++++++++++++++++++++++++++-------- > 1 file changed, 35 insertions(+), 8 deletions(-) > > diff --git a/drivers/input/joystick/xpad.c b/drivers/input/joystick/xpad.c > index 3349861..a9ff4c2 100644 > --- a/drivers/input/joystick/xpad.c > +++ b/drivers/input/joystick/xpad.c > @@ -343,8 +343,12 @@ struct usb_xpad { > int xtype; /* type of xbox device */ > unsigned long pad_nr; /* the order x360 pads were attached */ > const char *name; /* name of the device */ > + struct work_struct work; /* init/remove device from callback */ > }; > > +static int xpad_init_input(struct usb_xpad *xpad); > +static void xpad_deinit_input(struct usb_xpad *xpad); > + > /* > * xpad_process_packet > * > @@ -488,6 +492,22 @@ static void xpad360_process_packet(struct usb_xpad *xpad, > > static void xpad_identify_controller(struct usb_xpad *xpad); > > +static void presence_work_function(struct work_struct *work) > +{ > + struct usb_xpad *xpad = container_of(work, struct usb_xpad, work); > + int error; > + > + if (xpad->pad_present) { > + error = xpad_init_input(xpad); > + if (error) { > + /* complain only, not much else we can do here */ > + dev_err(&xpad->dev->dev, "unable to init device\n"); > + } > + } else { > + xpad_deinit_input(xpad); > + } > +} > + > /* > * xpad360w_process_packet > * > @@ -504,13 +524,16 @@ static void xpad_identify_controller(struct usb_xpad *xpad); > */ > static void xpad360w_process_packet(struct usb_xpad *xpad, u16 cmd, unsigned char *data) > { > + int presence; > + > /* Presence change */ > if (data[0] & 0x08) { > - if (data[1] & 0x80) { > - xpad->pad_present = 1; > - xpad_identify_controller(xpad); > - } else > - xpad->pad_present = 0; > + presence = (data[1] & 0x80) != 0; > + > + if (xpad->pad_present != presence) { > + xpad->pad_present = presence; > + schedule_work(&xpad->work); > + } > } So what happens if we start without the input device, schedule it to be added and then receive a valid pad data packet before work item had a chance to run and input device is still not created? We are going crash and burn :( Thanks.
diff --git a/drivers/input/joystick/xpad.c b/drivers/input/joystick/xpad.c index 3349861..a9ff4c2 100644 --- a/drivers/input/joystick/xpad.c +++ b/drivers/input/joystick/xpad.c @@ -343,8 +343,12 @@ struct usb_xpad { int xtype; /* type of xbox device */ unsigned long pad_nr; /* the order x360 pads were attached */ const char *name; /* name of the device */ + struct work_struct work; /* init/remove device from callback */ }; +static int xpad_init_input(struct usb_xpad *xpad); +static void xpad_deinit_input(struct usb_xpad *xpad); + /* * xpad_process_packet * @@ -488,6 +492,22 @@ static void xpad360_process_packet(struct usb_xpad *xpad, static void xpad_identify_controller(struct usb_xpad *xpad); +static void presence_work_function(struct work_struct *work) +{ + struct usb_xpad *xpad = container_of(work, struct usb_xpad, work); + int error; + + if (xpad->pad_present) { + error = xpad_init_input(xpad); + if (error) { + /* complain only, not much else we can do here */ + dev_err(&xpad->dev->dev, "unable to init device\n"); + } + } else { + xpad_deinit_input(xpad); + } +} + /* * xpad360w_process_packet * @@ -504,13 +524,16 @@ static void xpad_identify_controller(struct usb_xpad *xpad); */ static void xpad360w_process_packet(struct usb_xpad *xpad, u16 cmd, unsigned char *data) { + int presence; + /* Presence change */ if (data[0] & 0x08) { - if (data[1] & 0x80) { - xpad->pad_present = 1; - xpad_identify_controller(xpad); - } else - xpad->pad_present = 0; + presence = (data[1] & 0x80) != 0; + + if (xpad->pad_present != presence) { + xpad->pad_present = presence; + schedule_work(&xpad->work); + } } /* Valid pad data */ @@ -959,8 +982,6 @@ static int xpad_led_probe(struct usb_xpad *xpad) return error; } - xpad_identify_controller(xpad); - return 0; } @@ -1110,6 +1131,8 @@ static int xpad_init_input(struct usb_xpad *xpad) if (error) goto fail_input_register; + xpad_identify_controller(xpad); + return 0; fail_input_register: @@ -1174,6 +1197,7 @@ static int xpad_probe(struct usb_interface *intf, const struct usb_device_id *id xpad->mapping = xpad_device[i].mapping; xpad->xtype = xpad_device[i].xtype; xpad->name = xpad_device[i].name; + INIT_WORK(&xpad->work, presence_work_function); if (xpad->xtype == XTYPE_UNKNOWN) { if (intf->cur_altsetting->desc.bInterfaceClass == USB_CLASS_VENDOR_SPEC) { @@ -1274,7 +1298,8 @@ static void xpad_disconnect(struct usb_interface *intf) { struct usb_xpad *xpad = usb_get_intfdata (intf); - xpad_deinit_input(xpad); + if (xpad->pad_present) + xpad_deinit_input(xpad); xpad_deinit_output(xpad); if (xpad->xtype == XTYPE_XBOX360W) { @@ -1285,6 +1310,8 @@ static void xpad_disconnect(struct usb_interface *intf) usb_free_coherent(xpad->udev, XPAD_PKT_LEN, xpad->idata, xpad->idata_dma); + cancel_work_sync(&xpad->work); + kfree(xpad); usb_set_intfdata(intf, NULL);