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2009-06-03rfkill: document /dev/rfkillJohannes Berg1-1/+7
Add some blurb about /dev/rfkill to the documentation and fix the "transmiter" spelling error. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-06-03rfkill: rewriteJohannes Berg1-519/+78
This patch completely rewrites the rfkill core to address the following deficiencies: * all rfkill drivers need to implement polling where necessary rather than having one central implementation * updating the rfkill state cannot be done from arbitrary contexts, forcing drivers to use schedule_work and requiring lots of code * rfkill drivers need to keep track of soft/hard blocked internally -- the core should do this * the rfkill API has many unexpected quirks, for example being asymmetric wrt. alloc/free and register/unregister * rfkill can call back into a driver from within a function the driver called -- this is prone to deadlocks and generally should be avoided * rfkill-input pointlessly is a separate module * drivers need to #ifdef rfkill functions (unless they want to depend on or select RFKILL) -- rfkill should provide inlines that do nothing if it isn't compiled in * the rfkill structure is not opaque -- drivers need to initialise it correctly (lots of sanity checking code required) -- instead force drivers to pass the right variables to rfkill_alloc() * the documentation is hard to read because it always assumes the reader is completely clueless and contains way TOO MANY CAPS * the rfkill code needlessly uses a lot of locks and atomic operations in locked sections * fix LED trigger to actually change the LED when the radio state changes -- this wasn't done before Tested-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk> Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> [thinkpad] Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-23rfkill: remove user_claim stuffJohannes Berg1-10/+6
Almost all drivers do not support user_claim, so remove it completely and always report -EOPNOTSUPP to userspace. Since userspace cannot really drive rfkill _anyway_ (due to the odd restrictions imposed by the documentation) having this code is just pointless. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-11-01rfkill: add master_switch_mode and EPO lock to rfkill and rfkill-inputHenrique de Moraes Holschuh1-7/+13
Add of software-based sanity to rfkill and rfkill-input so that it can reproduce what hardware-based EPO switches do, blocking all transmitters and locking down any further attempts to unblock them until the switch is deactivated. rfkill-input is responsible for issuing the EPO control requests, like before. While an rfkill EPO is active, all transmitters are locked to one of the BLOCKED states and all attempts to change that through the rfkill API (userspace and kernel) will be either ignored or return -EPERM errors. The lock will be released upon receipt of EV_SW SW_RFKILL_ALL ON by rfkill-input, or should modular rfkill-input be unloaded. This makes rfkill and rfkill-input extend the operation of an existing wireless master kill switch to all wireless devices in the system, even those that are not under hardware or firmware control. Since the above is the expected operational behavior for the master rfkill switch, the EPO lock functionality is not optional. Also, extend rfkill-input to allow for three different behaviors when it receives an EV_SW SW_RFKILL_ALL ON input event. The user can set which behavior he wants through the master_switch_mode parameter: master_switch_mode = 0: EV_SW SW_RFKILL_ALL ON just unlocks rfkill controller state changes (so that the rfkill userspace and kernel APIs can now be used to change rfkill controller states again), but doesn't change any of their states (so they will all remain blocked). This is the safest mode of operation, as it requires explicit operator action to re-enable a transmitter. master_switch_mode = 1: EV_SW SW_RFKILL_ALL ON causes rfkill-input to attempt to restore the system to the state before the last EV_SW SW_RFKILL_ALL OFF event, or to the default global states if no EV_SW SW_RFKILL_ALL OFF ever happened. This is the recommended mode of operation for laptops. master_switch_mode = 2: tries to unblock all rfkill controllers (i.e. enable all transmitters) when an EV_SW SW_RFKILL_ALL ON event is received. This is the default mode of operation, as it mimics the previous behavior of rfkill-input. In order to implement these features in a clean way, the entire event handling of rfkill-input was refactored into a single worker function. Protection against input event DoS (repeatedly firing rfkill events for rfkill-input to process) was removed during the code refactoring. It will be added back in a future patch. Note that with these changes, rfkill-input doesn't need to explicitly handle any radio types for which KEY_<radio type> or SW_<radio type> events do not exist yet. Code to handle EV_SW SW_{WLAN,WWAN,BLUETOOTH,WIMAX,...} was added as it might be needed in the future (and its implementation is not that obvious), but is currently #ifdef'd out to avoid wasting resources. Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Cc: Ivo van Doorn <IvDoorn@gmail.com> Cc: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-09-16rfkill: remove transmitter blocking on suspendHenrique de Moraes Holschuh1-4/+28
Currently, rfkill would stand in the way of properly supporting wireless devices that are capable of waking the system up from sleep or hibernation when they receive a special wireless message. It would also get in the way of mesh devices that need to remain operational even during platform suspend. To avoid that, stop trying to block the transmitters on the rfkill class suspend handler. Drivers that need rfkill's older behaviour will have to implement it by themselves in their own suspend handling. Do note that rfkill *will* attempt to restore the transmitter state on resume in any situation. This happens after the driver's resume method is called by the suspend core (class devices resume after the devices they are attached to have been resumed). The following drivers need to check if they need to explicitly block their transmitters in their own suspend handlers (maintainers Cc'd): arch/arm/mach-pxa/tosa-bt.c drivers/net/usb/hso.c drivers/net/wireless/rt2x00/* (USB might need it?) drivers/net/wireless/b43/ (SSB over USB might need it?) drivers/misc/hp-wmi.c eeepc-laptop w/rfkill support (not in mainline yet) Compal laptop w/rfkill support (not in mainline yet) toshiba-acpi w/rfkill support (not in mainline yet) Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Cc: Ivo van Doorn <IvDoorn@gmail.com> Cc: Matthew Garrett <mjg@redhat.com> Cc: Andrew Bird <ajb@spheresystems.co.uk> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Cezary Jackiewicz <cezary.jackiewicz@gmail.com> Cc: Philip Langdale <philipl@overt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-08-18rfkill: protect suspended rfkill controllersHenrique de Moraes Holschuh1-0/+5
Guard rfkill controllers attached to a rfkill class against state changes after class suspend has been issued. Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Acked-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-07-30rfkill: document rfkill_force_state as required (v2)Henrique de Moraes Holschuh1-4/+16
While the rfkill class does work with just get_state(), it doesn't work well on devices that are subject to external events that cause rfkill state changes. Document that rfkill_force_state() is required in those cases. Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Acked-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-06-26rfkill: improve documentation for kernel driversHenrique de Moraes Holschuh1-60/+201
Improve the documentation of how to use the rfkill class in kernel drivers, based on the doubts that came up in a thread in linux-wireless. Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Acked-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-06-26rfkill: rename the rfkill_state states and add block-locked stateHenrique de Moraes Holschuh1-9/+47
The current naming of rfkill_state causes a lot of confusion: not only the "kill" in rfkill suggests negative logic, but also the fact that rfkill cannot turn anything on (it can just force something off or stop forcing something off) is often forgotten. Rename RFKILL_STATE_OFF to RFKILL_STATE_SOFT_BLOCKED (transmitter is blocked and will not operate; state can be changed by a toggle_radio request), and RFKILL_STATE_ON to RFKILL_STATE_UNBLOCKED (transmitter is not blocked, and may operate). Also, add a new third state, RFKILL_STATE_HARD_BLOCKED (transmitter is blocked and will not operate; state cannot be changed through a toggle_radio request), which is used by drivers to indicate a wireless transmiter was blocked by a hardware rfkill line that accepts no overrides. Keep the old names as #defines, but document them as deprecated. This way, drivers can be converted to the new names *and* verified to actually use rfkill correctly one by one. Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Acked-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-06-26rfkill: document rw rfkill switches and clarify input subsystem interactionsHenrique de Moraes Holschuh1-55/+308
Rework the documentation so as to make sure driver writers understand exactly where the boundaries are for input drivers related to rfkill switches, buttons and keys, and rfkill class drivers. Also fix a small error in the documentation: setting the state of a normal instance of the rfkill class does not affect the state of any other devices (unless they are tied by firmware/hardware somehow). Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Acked-by: Ivo van Doorn <IvDoorn@gmail.com> Cc: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-06-26rfkill: clarify meaning of rfkill statesHenrique de Moraes Holschuh1-0/+7
rfkill really should have been named rfswitch. As it is, one can get confused whether RFKILL_STATE_ON means the KILL switch is on (and therefore, the radio is being *blocked* from operating), or whether it means the RADIO rf output is on. Clearly state that RFKILL_STATE_ON means the radio is *unblocked* from operating (i.e. there is no rf killing going on). Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Acked-by: Ivo van Doorn <IvDoorn@gmail.com> Cc: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-11[RFKILL]: Add rfkill documentationIvo van Doorn1-0/+89
Add a documentation file which contains a short description about rfkill with some notes about drivers and the userspace interface. Changes since v1 and v2: - Spellchecking Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Acked-by: Dmitry Torokhov <dtor@mail.ru> Acked-by: Randy Dunlap <randy.dunlap@oracle.com>