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* NFC: digital: Add NFC-DEP Target-side ATN SupportMark A. Greer2014-11-28
| | | | | | | | | | | | | | | | | | | When an NFC-DEP target receives an ATN PDU, its supposed to respond with a similar ATN PDU. When the Target receives an I PDU with the PNI one less than the current PNI and the last PDU sent was an ATN PDU, the Target is to resend the last non-ATN PDU that it has sent. This is described in section 14.12.3.4 of the NFC Digital Protocol Spec. The digital layer's NFC-DEP code doesn't implement this so add that support. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Add NFC-DEP Initiator-side ATN SupportMark A. Greer2014-11-28
| | | | | | | | | | | | | | | | | | | | | | | | When an NFC-DEP Initiator times out when waiting for a DEP_RES from the Target, its supposed to send an ATN to the Target. The Target should respond to the ATN with a similar ATN PDU and the Initiator can then resend the last non-ATN PDU that it sent. No more than 'N(retry,atn)' are to be send where 2 <= 'N(retry,atn)' <= 5. If the Initiator had just sent a NACK PDU when the timeout occurred, it is to continue sending NACKs until 'N(retry,nack)' NACKs have been send. This is described in section 14.12.5.6 of the NFC-DEP Digital Protocol Spec. The digital layer's NFC-DEP code doesn't implement this so add that support. The value chosen for 'N(retry,atn)' is 2. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Add NFC-DEP Target-side NACK SupportMark A. Greer2014-11-28
| | | | | | | | | | | | | | | | | | | | | | | | | When an NFC-DEP Target receives a NACK PDU with a PNI equal to 1 less than the current PNI, it is supposed to re-send the last PDU. This is implied in section 14.12.5.4 of the NFC Digital Protocol Spec. The digital layer's NFC-DEP code doesn't implement Target-side NACK handing so add it. The last PDU that was sent is saved in the 'nfc_digital_dev' structure's 'saved_skb' member. The skb will have an additional reference taken to ensure that the skb isn't freed when the driver performs a kfree_skb() on the skb. The length of the skb/PDU is also saved so the length can be restored when re-sending the PDU in the skb (the driver will perform an skb_pull() so an skb_push() needs to be done to restore the skb's data pointer/length). Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Add NFC-DEP Initiator-side NACK SupportMark A. Greer2014-11-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an NFC-DEP Initiator receives a frame with an incorrect CRC or with a parity error, and the frame is at least 4 bytes long, its supposed to send a NACK to the Target. The Initiator can send up to 'N(retry,nack)' consecutive NACKs where 2 <= 'N(retry,nack)' <= 5. When the limit is exceeded, a PROTOCOL EXCEPTION is raised. Any other type of transmission error is to be ignored and the Initiator should continue waiting for a new frame. This is described in section 14.12.5.4 of the NFC Digital Protocol Spec. The digital layer's NFC-DEP code doesn't implement any of this so add it. This support diverges from the spec in two significant ways: a) NACKs will be sent for ANY error reported by the driver except a timeout. This is done because there is currently no way for the digital layer to distinguish a CRC or parity error from any other type of error reported by the driver. b) All other errors will cause a PROTOCOL EXCEPTION even frames with CRC errors that are less than 4 bytes. The value chosen for 'N(retry,nack)' is 2. Targets do not send NACK PDUs. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Add NFC-DEP Receive Chaining SupportMark A. Greer2014-11-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the peer in an NFC-DEP exchange has a packet to send that is larger than the local maximum payload, it sets the 'MI' bit in the 'I' PDU. This indicates that NFC-DEP chaining is to occur. When such a PDU is received, the local side responds with an 'ACK' PDU and this continues until the peer sends an 'I' PDU with the 'MI' bit cleared. This indicates that the chaining sequence is complete and the entire packet has been transferred. Receiving chained PDUs is currently not supported by the digital layer so add that support. When a chaining sequence is initiated by the peer, the digital layer will allocate an skb large enough to hold 8 maximum sized frame payloads. The maximum payload can range from 64 to 254 bytes so 8 * 254 = 2032 seems like a reasonable compromise between potentially wasting memory and constantly reallocating new, larger skbs. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Add NFC-DEP Send Chaining SupportMark A. Greer2014-11-28
| | | | | | | | | | | | | | | | | | | | | | | | | When the NFC-DEP code is given a packet to send that is larger than the peer's maximum payload, its supposed to set the 'MI' bit in the 'I' PDU's Protocol Frame Byte (PFB). Setting this bit indicates that NFC-DEP chaining is to occur. When NFC-DEP chaining is progress, sender 'I' PDUs are acknowledged with 'ACK' PDUs until the last 'I' PDU in the chain (which has the 'MI' bit cleared) is responded to with a normal 'I' PDU. This can occur while in Initiator mode or in Target mode. Sender NFC-DEP chaining is currently not implemented in the digital layer so add that support. Unfortunately, since sending a frame may require writing the CRC to the end of the data, the relevant data part of the original skb must be copied for each intermediate frame. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Implement NFC-DEP max payload lengthsMark A. Greer2014-11-28
| | | | | | | | | | | | | | | | | | | | | The maximum payload for NFC-DEP exchanges (i.e., the number of bytes between SoD and EoD) is negotiated using the ATR_REQ, ATR_RES, and PSL_REQ commands. The valid maximum lengths are 64, 128, 192, and 254 bytes. Currently, NFC-DEP code assumes that both sides are always using 254 byte maximums and ignores attempts by the peer to change it. Instead, implement the negotiation code, enforce the local maximum when receiving data from the peer, and don't send payloads that exceed the remote's maximum. The default local maximum is 254 bytes. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Enforce NFC-DEP PNI sequencingMark A. Greer2014-11-28
| | | | | | | | | | | | | | | NFC-DEP DEP_REQ and DEP_RES exchanges using 'I' and 'ACK/NACK' PDUs have a sequence number called the Packet Number Information (PNI). The PNI is incremented (modulo 4) after every DEP_REQ/ DEP_RES pair and should be verified by the digital layer code. That verification isn't always done, though, so add code to make sure that it is done. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Ensure no NAD byte in DEP_REQ and DEP_RES framesMark A. Greer2014-11-28
| | | | | | | | | | | | According to chapter 14 of the NFC-DEP Digital Protocol Spec., the NAD byte should never be present in DEP_REQ or DEP_RES frames. However, this is not enforced so add that enforcement code. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Add Target-mode NFC-DEP DID SupportMark A. Greer2014-11-28
| | | | | | | | | | | | | | | | | | | | | | | | | | When in Target mode, the Initiator specifies whether subsequent DEP_REQ and DEP_RES frames will include a DID byte by the value passed in the ATR_REQ. If the DID value in the ATR_REQ is '0' then no DID byte will be included. If the DID value is between '1' and '14' then a DID byte containing the same value must be included in subsequent DEP_REQ and DEP_RES frames. Any other DID value is invalid. This is specified in sections 14.8.1.2 and 14.8.2.2 of the NFC Digital Protocol Spec. Checking the DID value (if it should be there at all), is not currently supported by the digital layer's NFC-DEP code. Add this support by remembering the DID value in the ATR_REQ, checking the DID value of received DEP_REQ frames (if it should be there at all), and including the remembered DID value in DEP_RES frames when appropriate. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Ensure no DID in NFC-DEP responsesMark A. Greer2014-11-28
| | | | | | | | | | | | | | | | | | | When in Initiator mode, the digital layer's NFC-DEP code always sets the Device ID (DID) value in the ATR_REQ to '0'. This means that subsequent DEP_REQ and DEP_RES frames must never include a DID byte. This is specified in sections 14.8.1.1 and 14.8.2.1 of the NFC Digital Protocol Spec. Currently, the digital layer's NFC-DEP code doesn't enforce this rule so add code to ensure that there is no DID byte in DEP_RES frames. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Rearrange NFC-DEP DEP_REQ/DEP_RES CodeMark A. Greer2014-11-28
| | | | | | | | | | | | Rearrange some of the code in digital_in_recv_dep_res() and digital_tg_recv_dep_req() so the initial code looks similar. The real reason is prepare the code for some upcoming patches that require these changes. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Fix potential skb leaks in NFC-DEP codeMark A. Greer2014-11-28
| | | | | | | | | | | | | When digital_in_send_cmd() or digital_tg_send_cmd() fail, they do not free the skb that was passed to them so the routine that allocated the skb should free it. Currently, there are several routines in the NFC-DEP code that don't do this so make them. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Add Inititor-side PSL supportMark A. Greer2014-08-31
| | | | | | | | | | | | | In order to operate at the fasted bit rate possible, add initiator-side support for PSL REQ while in P2P mode. The PSL REQ will switch the RF technology to 424F whenever possible. Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com> Tested-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* Merge tag 'master-2014-07-31' of ↵David S. Miller2014-08-05
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next Conflicts: net/6lowpan/iphc.c Minor conflicts in iphc.c were changes overlapping with some style cleanups. John W. Linville says: ==================== Please pull this last(?) batch of wireless change intended for the 3.17 stream... For the NFC bits, Samuel says: "This is a rather quiet one, we have: - A new driver from ST Microelectronics for their NCI ST21NFCB, including device tree support. - p2p support for the ST21NFCA driver - A few fixes an enhancements for the NFC digital laye" For the Atheros bits, Kalle says: "Michal and Janusz did some important RX aggregation fixes, basically we were missing RX reordering altogether. The 10.1 firmware doesn't support Ad-Hoc mode and Michal fixed ath10k so that it doesn't advertise Ad-Hoc support with that firmware. Also he implemented a workaround for a KVM issue." For the Bluetooth bits, Gustavo and Johan say: "To quote Gustavo from his previous request: 'Some last minute fixes for -next. We have a fix for a use after free in RFCOMM, another fix to an issue with ADV_DIRECT_IND and one for ADV_IND with auto-connection handling. Last, we added support for reading the codec and MWS setting for controllers that support these features.' Additionally there are fixes to LE scanning, an update to conform to the 4.1 core specification as well as fixes for tracking the page scan state. All of these fixes are important for 3.17." And, "We've got: - 6lowpan fixes/cleanups - A couple crash fixes, one for the Marvell HCI driver and another in LE SMP. - Fix for an incorrect connected state check - Fix for the bondable requirement during pairing (an issue which had crept in because of using "pairable" when in fact the actual meaning was "bondable" (these have different meanings in Bluetooth)" Along with those are some late-breaking hardware support patches in brcmfmac and b43 as well as a stray ath9k patch. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * NFC: digital: Clear poll_tech_count before activating targetMark A. Greer2014-07-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, digital_target_found() has a race between the events started by calling nfc_targets_found() (which ultimately expect ddev->poll_tech_count to be zero) and setting ddev->poll_tech_count to zero after the call to nfc_targets_found(). When the race is "lost" (i.e., ddev->poll_tech_count is found to not be zero by the events started by nfc_targets_found()), an error message is printed and the target is not found. A similar race exists when digital_tg_recv_atr_req() calls nfc_tm_activated(). Fix this by first saving the current value of ddev->poll_tech_count and then clearing it before calling nfc_targets_found()/nfc_tm_activated(). Clearing ddev->poll_tech_count before calling nfc_targets_found()/nfc_tm_activated() eliminates the race. Saving the value is required so it can be restored when nfc_targets_found()/nfc_tm_activated() fails and polling needs to continue. Acked-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* | NFC: remove unnecessary break after gotoFabian Frederick2014-07-15
|/ | | | | Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: David S. Miller <davem@davemloft.net>
* NFC: digital: Return proper error code when sending ATR_REQThierry Escande2014-05-25
| | | | | | | | The error code returned by digital_in_send_cmd() was not returned by digital_in_send_atr_req(). Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2014-01-25
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking updates from David Miller: 1) BPF debugger and asm tool by Daniel Borkmann. 2) Speed up create/bind in AF_PACKET, also from Daniel Borkmann. 3) Correct reciprocal_divide and update users, from Hannes Frederic Sowa and Daniel Borkmann. 4) Currently we only have a "set" operation for the hw timestamp socket ioctl, add a "get" operation to match. From Ben Hutchings. 5) Add better trace events for debugging driver datapath problems, also from Ben Hutchings. 6) Implement auto corking in TCP, from Eric Dumazet. Basically, if we have a small send and a previous packet is already in the qdisc or device queue, defer until TX completion or we get more data. 7) Allow userspace to manage ipv6 temporary addresses, from Jiri Pirko. 8) Add a qdisc bypass option for AF_PACKET sockets, from Daniel Borkmann. 9) Share IP header compression code between Bluetooth and IEEE802154 layers, from Jukka Rissanen. 10) Fix ipv6 router reachability probing, from Jiri Benc. 11) Allow packets to be captured on macvtap devices, from Vlad Yasevich. 12) Support tunneling in GRO layer, from Jerry Chu. 13) Allow bonding to be configured fully using netlink, from Scott Feldman. 14) Allow AF_PACKET users to obtain the VLAN TPID, just like they can already get the TCI. From Atzm Watanabe. 15) New "Heavy Hitter" qdisc, from Terry Lam. 16) Significantly improve the IPSEC support in pktgen, from Fan Du. 17) Allow ipv4 tunnels to cache routes, just like sockets. From Tom Herbert. 18) Add Proportional Integral Enhanced packet scheduler, from Vijay Subramanian. 19) Allow openvswitch to mmap'd netlink, from Thomas Graf. 20) Key TCP metrics blobs also by source address, not just destination address. From Christoph Paasch. 21) Support 10G in generic phylib. From Andy Fleming. 22) Try to short-circuit GRO flow compares using device provided RX hash, if provided. From Tom Herbert. The wireless and netfilter folks have been busy little bees too. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2064 commits) net/cxgb4: Fix referencing freed adapter ipv6: reallocate addrconf router for ipv6 address when lo device up fib_frontend: fix possible NULL pointer dereference rtnetlink: remove IFLA_BOND_SLAVE definition rtnetlink: remove check for fill_slave_info in rtnl_have_link_slave_info qlcnic: update version to 5.3.55 qlcnic: Enhance logic to calculate msix vectors. qlcnic: Refactor interrupt coalescing code for all adapters. qlcnic: Update poll controller code path qlcnic: Interrupt code cleanup qlcnic: Enhance Tx timeout debugging. qlcnic: Use bool for rx_mac_learn. bonding: fix u64 division rtnetlink: add missing IFLA_BOND_AD_INFO_UNSPEC sfc: Use the correct maximum TX DMA ring size for SFC9100 Add Shradha Shah as the sfc driver maintainer. net/vxlan: Share RX skb de-marking and checksum checks with ovs tulip: cleanup by using ARRAY_SIZE() ip_tunnel: clear IPCB in ip_tunnel_xmit() in case dst_link_failure() is called net/cxgb4: Don't retrieve stats during recovery ...
| * NFC: digital: Set rf tech and crc functions when receiving a PSL_REQThierry Escande2014-01-07
| | | | | | | | | | | | | | | | This patch sets the correct rf tech value and crc functions in target mode when receiving a PSL_REQ, as done when receiving an ATR_REQ. Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
| * NFC: digital: Set current target active on activate_target() callThierry Escande2014-01-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The curr_protocol field of nfc_digital_dev structure used to determine if a target is currently active was set too soon, immediately when a target is found. This is not good since there is no other way than deactivate_target() to reset curr_protocol and if activate_target() is not called, the target remains active and it's not possible to put the device in poll mode anymore. With this patch curr_protocol is set when nfc core activates a target, puts a device up, or when an ATR_REQ is received in target mode. Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
| * NFC: digital: Use NFC_NFCID3_MAXSIZE from nfc.hThierry Escande2014-01-03
| | | | | | | | | | | | | | | | | | | | | | This removes the declaration of NFCID3 size in digital_dep.c and now uses the one from nfc.h. This also removes a faulty and unneeded call to max(). Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
| * NFC: digital: Fix incorrect use of ERR_PTR and PTR_ERR macrosThierry Escande2014-01-03
| | | | | | | | | | | | | | | | It's bad to use these macros when not dealing with error code. this patch changes calls to these macros with correct casts. Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* | treewide: Fix typos in printkMasanari Iida2013-12-19
|/ | | | | | | | Correct spelling typo in various part of kernel Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* NFC: digital: Add newline to pr_* callsSamuel Ortiz2013-09-24
| | | | | | | | We do not add the newline to the pr_fmt macro, in order to give more flexibility to the caller and to keep the logging style consistent with the rest of the NFC and kernel code. Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC: digital: Remove PR_ERR and PR_DBG macrosSamuel Ortiz2013-09-24
| | | | | | | They can be replaced by the standard pr_err and pr_debug one after defining the right pr_fmt macro. Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC Digital: Add target NFC-DEP supportThierry Escande2013-09-24
| | | | | | | | | | | | | | | | | | This adds support for NFC-DEP target mode for NFC-A and NFC-F technologies. If the driver provides it, the stack uses an automatic mode for technology detection and automatic anti-collision. Otherwise the stack tries to use non-automatic synchronization and listens for SENS_REQ and SENSF_REQ commands. The detection, activation, and data exchange procedures work exactly the same way as in initiator mode, as described in the previous commits, except that the digital stack waits for commands and sends responses back to the peer device. Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
* NFC Digital: Add initiator NFC-DEP supportThierry Escande2013-09-24
This adds support for NFC-DEP protocol in initiator mode for NFC-A and NFC-F technologies. When a target is detected, the process flow is as follow: For NFC-A technology: 1 - The digital stack receives a SEL_RES as the reply of the SEL_REQ command. 2 - If b7 of SEL_RES is set, the peer device is configure for NFC-DEP protocol. NFC core is notified through nfc_targets_found(). Execution continues at step 4. 3 - Otherwise, it's a tag and the NFC core is notified. Detection ends. 4 - The digital stacks sends an ATR_REQ command containing a randomly generated NFCID3 and the general bytes obtained from the LLCP layer of NFC core. For NFC-F technology: 1 - The digital stack receives a SENSF_RES as the reply of the SENSF_REQ command. 2 - If B1 and B2 of NFCID2 are 0x01 and 0xFE respectively, the peer device is configured for NFC-DEP protocol. NFC core is notified through nfc_targets_found(). Execution continues at step 4. 3 - Otherwise it's a type 3 tag. NFC core is notified. Detection ends. 4 - The digital stacks sends an ATR_REQ command containing the NFC-F NFCID2 as NFCID3 and the general bytes obtained from the LLCP layer of NFC core. For both technologies: 5 - The digital stacks receives the ATR_RES response containing the NFCID3 and the general bytes of the peer device. 6 - The digital stack notifies NFC core that the DEP link is up through nfc_dep_link_up(). 7 - The NFC core performs data exchange through tm_transceive(). 8 - The digital stack sends a DEP_REQ command containing an I PDU with the data from NFC core. 9 - The digital stack receives a DEP_RES command 10 - If the DEP_RES response contains a supervisor PDU with timeout extension request (RTOX) the digital stack sends a DEP_REQ command containing a supervisor PDU acknowledging the RTOX request. The execution continues at step 9. 11 - If the DEP_RES response contains an I PDU, the response data is passed back to NFC core through the response callback. The execution continues at step 8. Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>