diff options
Diffstat (limited to 'drivers/staging/comedi/drivers/dt9812.c')
| -rw-r--r-- | drivers/staging/comedi/drivers/dt9812.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/staging/comedi/drivers/dt9812.c b/drivers/staging/comedi/drivers/dt9812.c index 96caae36279c..06059850dae2 100644 --- a/drivers/staging/comedi/drivers/dt9812.c +++ b/drivers/staging/comedi/drivers/dt9812.c @@ -262,7 +262,7 @@ struct dt9812_usb_cmd { #define DT9812_NUM_SLOTS 16 -static DECLARE_MUTEX(dt9812_mutex); +static DEFINE_SEMAPHORE(dt9812_mutex); static const struct usb_device_id dt9812_table[] = { {USB_DEVICE(0x0867, 0x9812)}, @@ -890,8 +890,10 @@ static struct usb_driver dt9812_usb_driver = { * Comedi functions */ -static void dt9812_comedi_open(struct comedi_device *dev) +static int dt9812_comedi_open(struct comedi_device *dev) { + int result = -ENODEV; + down(&devpriv->slot->mutex); if (devpriv->slot->usb) { /* We have an attached device, fill in current range info */ @@ -934,8 +936,10 @@ static void dt9812_comedi_open(struct comedi_device *dev) } break; } + result = 0; } up(&devpriv->slot->mutex); + return result; } static int dt9812_di_rinsn(struct comedi_device *dev, @@ -1124,7 +1128,7 @@ static int __init usb_dt9812_init(void) /* Initialize all driver slots */ for (i = 0; i < DT9812_NUM_SLOTS; i++) { - init_MUTEX(&dt9812[i].mutex); + sema_init(&dt9812[i].mutex, 1); dt9812[i].serial = 0; dt9812[i].usb = NULL; dt9812[i].comedi = NULL; |