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path: root/drivers/misc/mei/bus.c
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2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-31mei: bus: unregister callbacks upon me client disable callAlexander Usyskin
Stop and unregister receive and notification callbacks from the disable function, to allow its later re-enablement. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-31mei: bus: prevent hardware module unload if device on bus is activeAlexander Usyskin
The hardware module should not be unloaded if the bus has active devices. Get get_/put_ bus parent module upon client device connection/disconnection, to prevent the hardware managing module to disappear underneath. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-31mei: bus: cancel and disable callback after release callAlexander Usyskin
A driver on the mei bus may rely on the availability of the receive callback during driver remove() call, e.g. mei_wdt. Move callbacks dismantling after the remove() call to unblock that scenario. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-04mei: bus: fix mei_cldev_enable KDocAlexander Usyskin
Adjust function name in KDoc. Fixes: d49dc5e76fc9 (mei: bus: use mei_cldev_ prefix for the API functions) Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-06mei: bus: enable non-blocking RXAlexander Usyskin
Enable non-blocking receive for drivers on mei bus, this allows checking for data availability by mei client drivers. This is most effective for fixed address clients, that lacks flow control. This function adds new API function mei_cldev_recv_nonblock(), it retuns -EGAIN if function will block. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-17mei: bus: split RX and async notification callbacksAlexander Usyskin
Split callbacks for RX and async notification events on mei bus to eliminate synchronization problems and to open way for RX optimizations. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-17mei: bus: make a client pointer always availableAlexander Usyskin
Change life time of the client pointer, allocate it upon client device creation and free it upon device destruction, instead of upon connection and disconnection. This helps to eliminate racy NULL checks in the bus code. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-10mei: enable to set the internal flag for client writeAlexander Usyskin
Prepare the client write functions to set the internal flag in message header. Carry both blocking and internal modes inside the transmit cb, and call internal bus function __mei_cl_send() with send mode bit mask. The Internal flag should be added only on messages generated by the driver. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31mei: bus: demote error to debug level upon disconnectAlexander Usyskin
A mei client driver on the mei client bus can call disconnect function on already internal disconnected client. A client can disconnect internally, for example, during link reset or upon FW request. Those are legitimate flows and we should not log an error message, hence we demote 'Already disconnected' message to the debug level. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28mei: bus: remove rx callback contextTomas Winkler
The callback context is redunant as all the information can be retrived from the device struture of its private data. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-30mei: amthif: fix deadlock in initialization during a resetAlexander Usyskin
The device lock was unnecessary obtained in bus rescan work before the amthif client search. That causes incorrect lock ordering and task hang: ... [88004.613213] INFO: task kworker/1:14:21832 blocked for more than 120 seconds. ... [88004.645934] Workqueue: events mei_cl_bus_rescan_work ... The correct lock order is cl_bus_lock device_lock me_clients_rwsem Move device_lock into amthif init function that called after me_clients_rwsem is released. This fixes regression introduced by commit: commit 025fb792bac3 ("mei: split amthif client init from end of clients enumeration") Cc: <stable@vger.kernel.org> # 4.6+ Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-30mei: add wrapper for queuing control commands.Tomas Winkler
Enclose the boiler plate code of allocating a control/hbm command cb and enqueueing it onto ctrl_wr.list in a convenient wrapper mei_cl_enqueue_ctrl_wr_cb(). This is a preparatory patch for enabling consecutive reads. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-30mei: fix return value on disconnectionTomas Winkler
Correct errno on client disconnection is -ENODEV not -EBUSY Cc: <stable@vger.kernel.org> #4.3+ Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-30mei: drop read complete queue emptiness checkAlexander Usyskin
In the course of the read flow we want to wait for read completion only if the read queue is empty. However the calling list_empty(&cl->rd_completed) is a duplication as the same check was performed by mei_cl_read_cb() and the waiting is skipped if it returns not NULL. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03mei: bus: call mei_cl_read_start under device lockAlexander Usyskin
Ensure that mei_cl_read_start is called under the device lock also in the bus layer. The function updates global ctrl_wr_list which should be locked. Cc: <stable@vger.kernel.org> #4.4+ Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30mei: do not pin module if cldrv->probe() failedAlexey Khoroshilov
If cldrv->probe() failed in mei_cl_device_probe(), the mei module is left pinned. The patch moves __module_get(THIS_MODULE) after cldrv->probe(). Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-31mei: bus: use scnprintf in *_showRasmus Villemoes
There's no reason to duplicate the logic provided by scnprintf(). Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-11mei: fix double freeing of a cb during link resetAlexander Usyskin
Fix double freeing of the cb that can happen if link reset kicks in the middle of blocked write from a device on the cl bus. Free cb inside mei_cl_write function on failure and drop cb free operation from callers, during a link reset the mei_cl_write function returns with an error, but the caller doesn't know if the cb was already queued or not so it doesn't know if the cb will be freed upon queue reclaim or it has to free it itself. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07mei: split amthif client init from end of clients enumerationAlexander Usyskin
The amthif FW client can appear after the end of client enumeration. Amthif host client initialization is done now at FW client discovery time. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07mei: bus: run rescan on me_clients list changeAlexander Usyskin
Since clients can be now added and removed during runtime we need to run bus rescan whenever me_clients list is modified. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07mei: drop reserved host client idsAlexander Usyskin
The reserved host clients can be obsoleted now, a portion of the platforms is shipped without iAMT enabled, where the reservation is not relevant and for platforms with iAMT dynamic allocation is sufficient. Dropping reserved ids makes enumeration more flexible and generic Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07mei: bus: check if the device is enabled before data transferAlexander Usyskin
The bus data transfer interface was missing the check if the device is in enabled state, this may lead to stack corruption during link reset. Cc: <stable@vger.kernel.org> #4.0 Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07mei: bus: fix notification event deliveryTomas Winkler
Call wake_up cl->ev_wait only in case there is no bus client registered to the event notification. Second, since we don't have exclusive waiter wake_up_interruptible_all is not used correctly here. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07mei: bus: fix RX event schedulingTomas Winkler
In this particular case this more correct and safer to check if the RX event is set in the event mask rather than query waitqueue_active Since the check is already performed in the mei_cl_bus_rx_event function, it is just required to check for its return value. Second, since we don't have exclusive waiter wake_up_interruptible_all is not used correctly here. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-29mei: bus: set the device name before running fixupTomas Winkler
The mei bus fixup use dev_xxx services for printing to kernel log so we need to setup the device name prior to running fixup hooks. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-29mei: bus: use correct lock orderingTomas Winkler
The correct lock order is cl_bus_lock device_lock me_clients_rwsem This order was violated in bus rescan and remove routines when me_client_rwsem was locked before cl_bus_lock. Chain exists of: [ 4.321653] &dev->device_lock --> &dev->me_clients_rwsem --> &dev->cl_bus_lock [ 4.321653] [ 4.321679] Possible unsafe locking scenario: [ 4.321679] [ 4.321693] CPU0 CPU1 [ 4.321701] ---- ---- [ 4.321709] lock(&dev->cl_bus_lock); [ 4.321720] lock(&dev->me_clients_rwsem); [ 4.321733] lock(&dev->cl_bus_lock); [ 4.321745] lock(&dev->device_lock); [ 4.321755] [ 4.321755] *** DEADLOCK *** [ 4.321755] Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17mei: bus: fix c&p issue in the kdocTomas Winkler
s/send/receive/ The buffer in the receive function is not used for sending Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-20mei: bus: use mei_cl_bus_ prefix consistentlyTomas Winkler
Use mei_cl_bus_ for internal bus function consistently. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-20mei: bus: use mei_cldev_ prefix for the API functionsTomas Winkler
Use mei_cldev_ prefix for all mei client bus api functions in order to resolve prefix conflict with functions that handle client function and are defined in client.c Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-20mei: bus: export mei_cldev_enabled functionTomas Winkler
Let me client device driver query of the device is connected and hence enabled. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-20mei: bus: export uuid and protocol version to mei_cl bus driversTomas Winkler
Export the uuid and the protocol version of the underlying me client for me client bus drivers usage. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-20mei: bus: add client protocol version to the device aliasTomas Winkler
The device alias now looks like mei:S:uuid:N:* In that way we can bind different drivers to clients with different protocol versions if required. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-20mei: bus: export client protocol versionTomas Winkler
export me client protocol version to sysfs and uevent Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-20mei: make modules.alias UUID information easier to readPrarit Bhargava
scripts/mod/file2alias.c:add_uuid() convert UUID into a single string which does not conform to the standard little endian UUID formatting. This patch changes add_uuid() to output same format as %pUL and modifies the mei driver to match the change. Signed-off-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: add and call callback on notify eventAlexander Usyskin
Enable drivers on mei client bus to subscribe to asynchronous event notifications. Introduce events_mask to the existing callback infrastructure so it is possible to handle both RX and event notification. Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: link client devices instead of host clientsTomas Winkler
MEI bus was designed around nfc and was hard to extend. Instead of the hard coded way of adding the devices on the mei bus we scan the whole me client list and create a device for each eligible me client (mei_cl_bus_rescan); currently we support only clients with single connection and fixed address clients. NFC radio name detection is run as a fixup routine The patch replaces handling the device list based on struct me_cl to device list based on me_cl_devices. The creating a connection is pushed from the device creation time to device enablement. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: simplify how we build nfc bus nameTomas Winkler
Remove the dependency on struct ndev from the nfc device name creation function so it is possible to use it in a fixup routine Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: enable running fixup routines before device registrationTomas Winkler
Split the device registration into allocation and device struct initialization, device setup, and the final device registration. This why it is possible to run fixups and quirks during the setup stage on an initialized device. Each fixup routine effects do_match flag. If the flag is set to false at the end the device won't be registered on the bus. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: add me client device list infrastructureTomas Winkler
Instead of holding the list of host clients (me_cl) we want to keep the list me client devices (mei_cl_device) This way we can create host to me client connection only when needed. Add list head to mei_cl_device and cl_bus_lock Add bus_added flag to the me client (mei_me_client) to track if the appropriate mei_cl_device was already created and is_added flag to mei_cl_device to track if it was already added to the device list across the bus rescans Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: add reference to bus device in struct mei_cl_clientTomas Winkler
Add reference to the bus device (mei_device) for easier access. To ensures that referencing cldev->bus is valid during cldev life time we increase the bus ref counter on a client device creation and drop it on the device release. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: revamp probe and remove functionsTomas Winkler
Instead of generating device id on the fly during probing we find the matching id entry on the device id table. Get bus the module reference counter so it cannot be unloaded after the driver has bounded to the client device Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: revamp device matchingTomas Winkler
mei_cl_device_match now calls mei_cl_device_find that returns the matching device id in the device id table. We will utilize the mei_cl_device_find during probing to locate the matching entry. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: report if event registration failedTomas Winkler
If event registeration has failed, the caller should know about it. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: don't enable events implicitly in device enableTomas Winkler
Do not enable events implicitly in mei_cl_enable_device, it should be done explicitly using mei_cl_register_event_cb so the events are enabled only when needed. The NFC drivers has been already using it that way so no need for further changes just remove the code from mei_cl_enable_device. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: rename uevent handler to mei_cl_device_ueventTomas Winkler
Rename mei_cl_uevent to mei_cl_device_uevent to match the naming convention of mei_cl_bus_type functions Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: move driver api functions at the start of the fileTomas Winkler
To make the file more organize move mei client driver api to the start of the file and add Kdoc. There are no functional changes in this patch. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-03mei: bus: fix drivers and devices names confusionTomas Winkler
In the mei bus layer there is use of different variables of driver and device types with no clear naming convention. There are generic struct device and struct driver, then mei_cl_{device, driver}, and finally mei_device which in this context serves as a bus device. The patch sets following naming convention: the variables of type struct device remains dev the variables of type struct driver remains drv the variables of type struct mei_cl_device are now cldev the variables of type struct mei_cl_driver are now cldrv the variables of type struct mei_device are now bus, in bus layer context Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-07mei: nfc: fix deadlock on shutdown/suspend pathTomas Winkler
In function mei_nfc_host_exit mei_cl_remove_device cannot be called under the device mutex as device removing flow invokes the device driver remove handler that calls in turn to mei_cl_disable_device which naturally acquires the device mutex. Also remove mei_cl_bus_remove_devices which has the same issue, but is never executed as currently the only device on the mei client bus is NFC and a new device cannot be easily added till the bus revamp is completed. This fixes regression caused by commit be9b720a0ccb ("mei_phy: move all nfc logic from mei driver to nfc") Prior to this change the nfc driver remove handler called to no-op disable function while actual nfc device was disabled directly from the mei driver. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Samuel Ortiz <sameo@linux.intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-05-31mei: fix up uuid matchingGreg Kroah-Hartman
A previous commit, c93b76b34b4d ("mei: bus: report also uuid in module alias") caused a build error as I missed applying a needed patch to add some macros to uapi/linux/uuid.h. Instead of those additional macros, change the mei code to use the existing uuid structure directly. Fixes: c93b76b34b4d Cc: Tomas Winkler <tomas.winkler@intel.com> Cc: Samuel Ortiz <sameo@linux.intel.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>