All in-kernel users of class_find_device() don't really need mutable
data for match callback.

In two places (kernel/power/suspend_test.c, drivers/scsi/osd/osd_uld.c)
this patch changes match callbacks to use const search data.

The const is propagated to rtc_class_open() and power_supply_get_by_name()
parameters.

Note that there's a dev reference leak in suspend_test.c that's not
touched in this patch.
Signed-off-by: NMichał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NSzymon Janc <szymon.janc@tieto.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

As a consequence the NFC device IDs won't be increasing all the time,
as IDR provides the first available ID.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

rf_mode is now set to NFC_RF_NONE when a device gets allocated,
when the link goes down, and when stop polling.
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

When the driver does not support checking the tag is still present, it
must return -EOPNOTSUPP. The NFC Core will then stop asking and not
report a tag lost event to user space.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The network merge brought in a few users of functions that got
deprecated by the workqueue cleanups: the 'system_nrt_wq' is now the
same as the regular system_wq, since all workqueues are now non-
reentrant.

Similarly, remove one use of flush_work_sync() - the regular
flush_work() has become synchronous, and the "_sync()" version is thus
deprecated as being superfluous.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

NFC is using a number of custom ordered workqueues w/ WQ_MEM_RECLAIM.
WQ_MEM_RECLAIM is unnecessary unless NFC is gonna be used as transport
for storage device, and all use cases match one work item to one
ordered workqueue - IOW, there's no actual ordering going on at all
and using system_nrt_wq gives the same behavior.

There's nothing to be gained by using custom workqueues.  Use
system_nrt_wq instead and drop all the custom ones.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

If the device is polling we sent a 0 target found event.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The semantics for a zero target found event is that the polling operation
could not complete.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

There can ever be only one call to nfc_targets_found() after polling
has been engaged. This could be from a target discovered event from
the driver, or from an error handler to notify poll will never complete.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This API should be used by drivers, HCI, SHDLC or NCI stacks to report an
unrecoverable error.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Even in target mode we need to let the driver know that we want to
bring the DEP link down.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This routine will be called by drivers whenever they receive data in target
mode. This should be unexpected events and as such should be handled by a
standalone API (i.e. not as a callback pointer from an existing API).
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

And rename the initiator mode data exchange ops for consistency sake.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Userspace gets a netlink event upon target mode activation.
The LLCP layer is also signaled when we get an ATR_REQ in order to get
the remote general bytes.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

It is now specified that nfc_target_found() and nfc_target_lost() core
functions must not be called from an atomic context. This allow us to
serialize calls and protect the targets table using the nfc device lock
instead of a spinlock.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The NFC Core now caches the active nfc target pointer, thereby avoiding
the need to lookup the target table for each invocation of a driver ops.
Consequently, pn533, HCI and NCI now directly receive an nfc_target
pointer instead of a target index.

Cc: Ilan Elias <ilane@ti.com>
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Use of "unsigned int" is preferred to bare "unsigned" in net tree.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some HW/drivers get notifications when a tag moves out of the radio field.
This notification is now forwarded to user space through netlink.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The target index can be used by userspace to uniquely identify a target
and thus should be kept unique, per NFC adapter. Moreover, some protocols
do not provide a logical index when discovering new targets, so we have to
generate one for them.
For NCI or pn533 to fetch their logical index, we added a logical_idx field
to the target structure.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

NFC drivers will call this routine when they detect that a tag leaves the
RF field. This will eventually lead to the corresponding netlink event
to be sent.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When calling nfc_dep_link_up, we implicitely are in initiator mode.
Which means we also can provide the general bytes as a function argument,
as all drivers will eventually request them.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The NFC core layer should not set the target_idx.
Instead, the driver layer (e.g. NCI, PN533) should set the
target_idx, so that it will be able to identify the target
when its I/F (e.g. activate_target) is called.
This is required in order to support multiple targets.
Note that currently supported drivers (PN533 and NCI) don't
use the target_idx in their implementation.
Signed-off-by: NIlan Elias <ilane@ti.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch is an initial implementation for the NFC Logical Link Control
protocol. It's also known as NFC peer to peer mode.
This is a basic implementation as it lacks SDP (services Discovery
Protocol), frames aggregation support, and frame rejecion parsing.
Follow up patches will implement those missing features.
This code has been tested against a Nexus S phone implementing LLCP 1.0.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Without an API for setting and getting the local and remote general bytes,
drivers won't be able to properly establish a DEP link.
This API also allows them to propagate the remote general bytes they get
from the DEP link establishment up to the LLCP layer.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

NFC-DEP (Data Exchange Protocol) is an NFC MAC layer.
This command allows to enable and disable the DEP link on to which e.g.
LLCP can run.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This is a factorization of the current rawsock tx skb allocation routine,
as it will be used by the LLCP code.
We also rename nfc_alloc_skb to nfc_alloc_recv_skb for consistency sake.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

All uses have been removed, so killing what's not necessary.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Using the standard debugging mechanisms is better than
subsystem specific ones when the subsystem doesn't use
a specific struct.

Coalesce long formats.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Using the normal logging styles is preferred over
subsystem specific styles when the subsystem does
not take a specific struct.

Convert nfc_<level> specific messages to pr_<level>
Add newlines to uses.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add 2 new nfc control operations:
dev_up to turn on the nfc device
dev_down to turn off the nfc device
Signed-off-by: NIlan Elias <ilane@ti.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>