diff options
Diffstat (limited to 'drivers/parport')
| -rw-r--r-- | drivers/parport/share.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/parport/share.c b/drivers/parport/share.c index 697c6d7bf0fe..8067f54ce050 100644 --- a/drivers/parport/share.c +++ b/drivers/parport/share.c @@ -708,6 +708,20 @@ parport_register_device(struct parport *port, const char *name, } } + if (flags & PARPORT_DEV_EXCL) { + if (port->physport->devices) { + /* + * If a device is already registered and this new + * device wants exclusive access, then no need to + * continue as we can not grant exclusive access to + * this device. + */ + pr_err("%s: cannot grant exclusive access for device %s\n", + port->name, name); + return NULL; + } + } + /* We up our own module reference count, and that of the port on which a device is to be registered, to ensure that neither of us gets unloaded while we sleep in (e.g.) @@ -827,6 +841,20 @@ parport_register_dev_model(struct parport *port, const char *name, } } + if (par_dev_cb->flags & PARPORT_DEV_EXCL) { + if (port->physport->devices) { + /* + * If a device is already registered and this new + * device wants exclusive access, then no need to + * continue as we can not grant exclusive access to + * this device. + */ + pr_err("%s: cannot grant exclusive access for device %s\n", + port->name, name); + return NULL; + } + } + if (!try_module_get(port->ops->owner)) return NULL; |