Hi, Sorry for the delay reviewing this. On Mon, 2016-02-08 at 10:41 -0500, João Paulo Rechi Vita wrote: > Provide an interface for the airplane-mode indicator be controlled > from > userspace. User has to first acquire the control through > RFKILL_OP_AIRPLANE_MODE_ACQUIRE and keep the fd open for the whole > time > it wants to be in control of the indicator. Closing the fd or using > RFKILL_OP_AIRPLANE_MODE_RELEASE restores the default policy. I've come to the conclusion that the new ops are probably the best thing to do here. > +Userspace can also override the default airplane-mode indicator > policy through > +/dev/rfkill. Control of the airplane mode indicator has to be > acquired first, > +using RFKILL_OP_AIRPLANE_MODE_ACQUIRE, and is only available for one > userspace > +application at a time. Closing the fd or using > RFKILL_OP_AIRPLANE_MODE_RELEASE > +reverts the airplane-mode indicator back to the default kernel > policy and makes > +it available for other applications to take control. Changes to the > +airplane-mode indicator state can be made using > RFKILL_OP_AIRPLANE_MODE_CHANGE, > +passing the new value in the 'soft' field of 'struct rfkill_event'. I don't really see any value in _RELEASE, since an application can just close the fd? I'd prefer not having the duplicate functionality and force us to exercise the single code path every time. > For further details consult Documentation/ABI/stable/sysfs-class- > rfkill. > diff --git a/include/uapi/linux/rfkill.h > b/include/uapi/linux/rfkill.h > index 2e00dce..9cb999b 100644 > --- a/include/uapi/linux/rfkill.h > +++ b/include/uapi/linux/rfkill.h > @@ -67,6 +67,9 @@ enum rfkill_operation { > RFKILL_OP_DEL, > RFKILL_OP_CHANGE, > RFKILL_OP_CHANGE_ALL, > + RFKILL_OP_AIRPLANE_MODE_ACQUIRE, > + RFKILL_OP_AIRPLANE_MODE_RELEASE, > + RFKILL_OP_AIRPLANE_MODE_CHANGE, > }; > @@ -1199,7 +1202,7 @@ static ssize_t rfkill_fop_write(struct file > *file, const char __user *buf, > if (copy_from_user(&ev, buf, count)) > return -EFAULT; > > - if (ev.op != RFKILL_OP_CHANGE && ev.op != > RFKILL_OP_CHANGE_ALL) > + if (ev.op < RFKILL_OP_CHANGE) > return -EINVAL; You need to also reject invalid high values, like 27. > mutex_lock(&rfkill_global_mutex); > > + if (ev.op == RFKILL_OP_AIRPLANE_MODE_ACQUIRE) { > + if (rfkill_apm_owned && !data->is_apm_owner) { > + count = -EACCES; > + } else { > + rfkill_apm_owned = true; > + data->is_apm_owner = true; > + } > + } > + > + if (ev.op == RFKILL_OP_AIRPLANE_MODE_RELEASE) { It would probably be better to simply use "switch (ev.op)" and make the default case do a reject. > if (ev.op == RFKILL_OP_CHANGE_ALL) > rfkill_update_global_state(ev.type, ev.soft); Also moving the existing code inside the switch, of course. johannes -- To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html