The latter seems to create invalid configuration, the device pointer passed to the attr callbacks is not correct afterwards (results into segfaults when accessing the attributes).
Signed-off-by: Andrej Krutak dev@andree.sk --- sound/usb/line6/podhd.c | 60 ++++++++++++++++++++++++++++++++++++------------- 1 file changed, 44 insertions(+), 16 deletions(-)
diff --git a/sound/usb/line6/podhd.c b/sound/usb/line6/podhd.c index 42fa376..f72803a 100644 --- a/sound/usb/line6/podhd.c +++ b/sound/usb/line6/podhd.c @@ -57,6 +57,9 @@ struct usb_line6_podhd {
/* Firmware version */ int firmware_version; + + /* Flag whether the sysfs files were created */ + int devfiles_created; };
static struct snd_ratden podhd_ratden = { @@ -177,16 +180,37 @@ static ssize_t firmware_version_show(struct device *dev, static DEVICE_ATTR_RO(firmware_version); static DEVICE_ATTR_RO(serial_number);
-static struct attribute *podhd_dev_attrs[] = { - &dev_attr_firmware_version.attr, - &dev_attr_serial_number.attr, - NULL -}; +/* + * Create sysfs entries. + */ +static int podhd_create_attrs(struct device *dev) +{ + int err; + struct usb_interface *interface = to_usb_interface(dev); + struct usb_line6_podhd *pod = usb_get_intfdata(interface);
-static const struct attribute_group podhd_dev_attr_group = { - .name = "podhd", - .attrs = podhd_dev_attrs, -}; + err = device_create_file(dev, &dev_attr_firmware_version); + if (err < 0) + return err; + err = device_create_file(dev, &dev_attr_serial_number); + if (err < 0) + return err; + + pod->devfiles_created = 1; + return 0; +} + +static void podhd_remove_attrs(struct device *dev) +{ + struct usb_interface *interface = to_usb_interface(dev); + struct usb_line6_podhd *pod = usb_get_intfdata(interface); + + if (pod->devfiles_created) { + device_remove_file(dev, &dev_attr_firmware_version); + device_remove_file(dev, &dev_attr_serial_number); + pod->devfiles_created = 0; + } +}
/* * POD X3 startup procedure. @@ -281,6 +305,14 @@ static int podhd_startup_finalize(struct usb_line6_podhd *pod) { struct usb_line6 *line6 = &pod->line6;
+ if (pod->line6.properties->capabilities & LINE6_CAP_CONTROL) { + /* create sysfs entries: */ + int err = podhd_create_attrs(line6->ifcdev); + + if (err < 0) + return err; + } + /* ALSA audio interface: */ return snd_card_register(line6->card); } @@ -288,8 +320,11 @@ static int podhd_startup_finalize(struct usb_line6_podhd *pod) static void podhd_disconnect(struct usb_line6 *line6) { struct usb_line6_podhd *pod = (struct usb_line6_podhd *)line6; + struct device *dev = line6->ifcdev;
if (pod->line6.properties->capabilities & LINE6_CAP_CONTROL) { + podhd_remove_attrs(dev); + del_timer_sync(&pod->startup_timer); cancel_work_sync(&pod->startup_work); } @@ -306,13 +341,6 @@ static int podhd_init(struct usb_line6 *line6,
line6->disconnect = podhd_disconnect;
- if (pod->line6.properties->capabilities & LINE6_CAP_CONTROL) { - /* create sysfs entries: */ - err = snd_card_add_dev_attr(line6->card, &podhd_dev_attr_group); - if (err < 0) - return err; - } - /* initialize MIDI subsystem: */ err = line6_init_midi(line6); if (err < 0)