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2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288Thomas Gleixner1-10/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 263 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.208660670@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-11NFC: digital: Add support for NFC DEP Response Waiting TimeThierry Escande1-0/+1
When sending an ATR_REQ, the initiator must wait for the ATR_RES at least 'RWT(nfcdep,activation) + dRWT(nfcdep)' and no more than 'RWT(nfcdep,activation) + dRWT(nfcdep) + dT(nfcdep,initiator)'. This gives a timeout value between 1237 ms and 1337 ms. This patch defines DIGITAL_ATR_RES_RWT to 1337 used for the timeout value of ATR_REQ command. For other DEP PDUs, the initiator must wait between 'RWT + dRWT(nfcdep)' and 'RWT + dRWT(nfcdep) + dT(nfcdep,initiator)' where RWT is given by the following formula: '(256 * 16 / f(c)) * 2^wt' where wt is the value of the TO field in the ATR_RES response and is in the range between 0 and 14. This patch declares a mapping table for wt values and gives RWT max values between 100 ms and 5049 ms. This patch also defines DIGITAL_ATR_RES_TO_WT, the maximum wt value in target mode, to 8. Signed-off-by: Thierry Escande <thierry.escande@collabora.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2016-07-11NFC: digital: Fix handling of saved PDU sk_buff pointersThierry Escande1-1/+0
This patch fixes the way an I-PDU is saved in case it needs to be sent again. It is now copied using pskb_copy() and not simply referenced using skb_get() since it could be modified by the driver. digital_in_send_saved_skb() and digital_tg_send_saved_skb() still get a reference on the saved skb which is re-sent but release it if the send operation fails. That way the caller doesn't have to take care about skb ref in case of error. RTOX supervisor PDU must not be saved as this can override a previously saved I-PDU that should be re-sent later on. Signed-off-by: Thierry Escande <thierry.escande@collabora.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2016-07-04NFC: digital: Add a delay between poll cyclesThierry Escande1-1/+1
This replaces the polling work struct with a delayed work struct and add a 10 ms delay between 2 poll cycles. This avoids to flood the device with 'switch off'/'switch on' commands. Signed-off-by: Thierry Escande <thierry.escande@collabora.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-11-28NFC: digital: Add NFC-DEP Initiator-side ATN SupportMark A. Greer1-0/+1
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>
2014-11-28NFC: digital: Add NFC-DEP Target-side NACK SupportMark A. Greer1-0/+3
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>
2014-11-28NFC: digital: Add NFC-DEP Initiator-side NACK SupportMark A. Greer1-0/+2
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>
2014-11-28NFC: digital: Add NFC-DEP Send Chaining SupportMark A. Greer1-0/+3
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>
2014-11-28NFC: digital: Implement NFC-DEP max payload lengthsMark A. Greer1-0/+3
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>
2014-11-28NFC: digital: Add Target-mode NFC-DEP DID SupportMark A. Greer1-0/+1
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>
2014-07-23NFC: digital: Add 'tg_listen_md' and 'tg_get_rf_tech' driver hooksMark A. Greer1-0/+12
The digital layer of the NFC subsystem currently supports a 'tg_listen_mdaa' driver hook that supports devices that can do mode detection and automatic anticollision. However, there are some devices that can do mode detection but not automatic anitcollision so add the 'tg_listen_md' hook to support those devices. In order for the digital layer to get the RF technology detected by the device from the driver, add the 'tg_get_rf_tech' hook. It is only valid to call this hook immediately after a successful call to 'tg_listen_md'. CC: 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>
2014-07-23NFC: digital: Remove extra blank lineMark A. Greer1-1/+0
Remove extra blank line that was inadvertently added by a recent commit. CC: 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>
2014-07-21NFC: digital: Add digital framing calls when in target modeMark A. Greer1-0/+2
Add new "NFC_DIGITAL_FRAMING_*" calls to the digital layer so the driver can make the necessary adjustments when performing anticollision while in target mode. The driver must ensure that the effect of these calls happens after the following response has been sent but before reception of the next request begins. 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>
2014-04-22NFC: digital: Add macros for the ISO/IEC 14443-B ProtocolMark A. Greer1-0/+4
Add RF tech and framing macros for the ISO/IEC 14443-B Protocol. Cc: 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>
2014-03-11NFC: digital: Rename Type V tags to Type 5 tagsMark A. Greer1-1/+1
According to the latest draft specification from the NFC-V committee, ISO/IEC 15693 tags will be referred to as "Type 5" tags and not "Type V" tags anymore. Make the code reflect the new terminology. Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-02-16NFC: digital: Add poll support for type 4A tag platformThierry Escande1-0/+3
This adds support for ATS request and response handling for type 4A tag activation. Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-02-16NFC: Add ISO/IEC 15693 header definitionsMark A. Greer1-0/+4
Add the header definitions required by upcoming patches that add support for ISO/IEC 15693. Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-01-04NFC: digital: Add a note about asynchronous functionsThierry Escande1-0/+10
This explains how and why the timeout parameter must be handled by the driver implementation. Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2013-09-25NFC Digital: Add NFC-A technology supportThierry Escande1-0/+3
This adds support for NFC-A technology at 106 kbits/s. The stack can detect tags of type 1 and 2. There is no support for collision detection. Tags can be read and written by using a user space application or a daemon like neard. The flow of polling operations for NFC-A detection is as follow: 1 - The digital stack sends the SENS_REQ command to the NFC device. 2 - The NFC device receives a SENS_RES response from a peer device and passes it to the digital stack. 3 - If the SENS_RES response identifies a type 1 tag, detection ends. NFC core is notified through nfc_targets_found(). 4 - Otherwise, the digital stack sets the cascade level of NFCID1 to CL1 and sends the SDD_REQ command. 5 - The digital stack selects SEL_CMD and SEL_PAR according to the cascade level and sends the SDD_REQ command. 4 - The digital stack receives a SDD_RES response for the cascade level passed in the SDD_REQ command. 5 - The digital stack analyses (part of) NFCID1 and verify BCC. 6 - The digital stack sends the SEL_REQ command with the NFCID1 received in the SDD_RES. 6 - The peer device replies with a SEL_RES response 7 - Detection ends if NFCID1 is complete. NFC core notified of new target by nfc_targets_found(). 8 - If NFCID1 is not complete, the cascade level is incremented (up to and including CL3) and the execution continues at step 5 to get the remaining bytes of NFCID1. Once target detection is done, type 1 and 2 tag commands must be handled by a user space application (i.e neard) through the NFC core. Responses for type 1 tag are returned directly to user space via NFC core. Responses of type 2 commands are handled differently. The digital stack doesn't analyse the type of commands sent through im_transceive() and must differentiate valid responses from error ones. The response process flow is as follow: 1 - If the response length is 16 bytes, it is a valid response of a READ command. the packet is returned to the NFC core through the callback passed to im_transceive(). Processing stops. 2 - If the response is 1 byte long and is a ACK byte (0x0A), it is a valid response of a WRITE command for example. First packet byte is set to 0 for no-error and passed back to the NFC core. Processing stops. 3 - Any other response is treated as an error and -EIO error code is returned to the NFC core through the response callback. Moreover, since the driver can't differentiate success response from a NACK response, the digital stack has to handle CRC calculation. Thus, this patch also adds support for CRC calculation. If the driver doesn't handle it, the digital stack will calculate CRC and will add it to sent frames. CRC will also be checked and removed from received frames. Pointers to the correct CRC calculation functions are stored in the digital stack device structure when a target is detected. This avoids the need to check the current target type for every call to im_transceive() and for every response received from a peer device. Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2013-09-25NFC Digital: Implement driver commands mechanismThierry Escande1-0/+25
This implements the mechanism used to send commands to the driver in initiator mode through in_send_cmd(). Commands are serialized and sent to the driver by using a work item on the system workqueue. Responses are handled asynchronously by another work item. Once the digital stack receives the response through the command_complete callback, the next command is sent to the driver. This also implements the polling mechanism. It's handled by a work item cycling on all supported protocols. The start poll command for a given protocol is sent to the driver using the mechanism described above. The process continues until a peer is discovered or stop_poll is called. This patch implements the poll function for NFC-A that sends a SENS_REQ command and waits for the SENS_RES response. Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2013-09-25NFC: Digital Protocol stack implementationThierry Escande1-0/+199
This is the initial commit of the NFC Digital Protocol stack implementation. It offers an interface for devices that don't have an embedded NFC Digital protocol stack. The driver instantiates the digital stack by calling nfc_digital_allocate_device(). Within the nfc_digital_ops structure, the driver specifies a set of function pointers for driver operations. These functions must be implemented by the driver and are: in_configure_hw: Hardware configuration for RF technology and communication framing in initiator mode. This is a synchronous function. in_send_cmd: Initiator mode data exchange using RF technology and framing previously set with in_configure_hw. The peer response is returned through callback cb. If an io error occurs or the peer didn't reply within the specified timeout (ms), the error code is passed back through the resp pointer. This is an asynchronous function. tg_configure_hw: Hardware configuration for RF technology and communication framing in target mode. This is a synchronous function. tg_send_cmd: Target mode data exchange using RF technology and framing previously set with tg_configure_hw. The peer next command is returned through callback cb. If an io error occurs or the peer didn't reply within the specified timeout (ms), the error code is passed back through the resp pointer. This is an asynchronous function. tg_listen: Put the device in listen mode waiting for data from the peer device. This is an asynchronous function. tg_listen_mdaa: If supported, put the device in automatic listen mode with mode detection and automatic anti-collision. In this mode, the device automatically detects the RF technology and executes the anti-collision detection using the command responses specified in mdaa_params. The mdaa_params structure contains SENS_RES, NFCID1, and SEL_RES for 106A RF tech. NFCID2 and system code (sc) for 212F and 424F. The driver returns the NFC-DEP ATR_REQ command through cb. The digital stack deducts the RF tech by analyzing the SoD of the frame containing the ATR_REQ command. This is an asynchronous function. switch_rf: Turns device radio on or off. The stack does not call explicitly switch_rf to turn the radio on. A call to in|tg_configure_hw must turn the device radio on. abort_cmd: Discard the last sent command. Then the driver registers itself against the digital stack by using nfc_digital_register_device() which in turn registers the digital stack against the NFC core layer. The digital stack implements common NFC operations like dev_up(), dev_down(), start_poll(), stop_poll(), etc. This patch is only a skeleton and NFC operations are just stubs. Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>