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: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

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: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

NCI SPI layer should not manage the nci dev, this is the job of the nci
chipset driver. This layer should be limited to frame/deframe nci
packets, and optionnaly check integrity (crc) and manage the ack/nak
protocol.

The NCI SPI must not be mixed up with an NCI dev. spi_[dev|device] are
therefore renamed to a simple spi for more clarity.
The header and crc sizes are moved to nci.h so that drivers can use
them to reserve space in outgoing skbs.
nci_spi_send() is exported to be accessible by drivers.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

struct nfc_phy_ops is not an HCI structure only, it can also be used by
NCI or direct NFC Core drivers.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

An hci dev is an hdev. An nci dev is an ndev. Calling an nci spi dev an
ndev is misleading since it's not the same thing. The nci dev contained
in the nci spi dev is also named inconsistently.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Use a more standard kernel style macro logging name.

Standardize the spacing of the "NFC: " prefix.
Add \n to uses, remove from macro.
Fix the defective uses that already had a \n.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Use the generic kernel function instead of a home-grown
one that does the same thing.

Add \n to uses not at the macro.  Don't add \n where
the nfc_dev_dbg macro mistakenly had them already.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This will be needed by all NFC driver implementing the SE ops.
Signed-off-by: NArron Wang <arron.wang@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Result is added as an NFC_ATTR_FIRMWARE_DOWNLOAD_STATUS attribute
containing the standard errno positive value of the completion result.
This event will be sent when the firmare download operation is done and
will contain the operation result.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This API must be called by NFC drivers, and its prototype was
incorrectly placed.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Loading a firmware into a target is typically called firmware
download, not firmware upload. So we rename the netlink API to
NFC_CMD_FW_DOWNLOAD in order to avoid any terminology confusion from
userspace.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This API will allow NFC drivers to add and remove the secure elements
they know about or detect. Typically this should be called (asynchronously
or not) from the driver or the host interface stack detect_se hook.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Secure elements need to be discovered after enabling the NFC controller.
This is typically done by the NCI core and the HCI drivers (HCI does not
specify how to discover SEs, it is left to the specific drivers).
Also, the SE enable/disable API explicitely takes a SE index as its
argument.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Supported secure elements are typically found during a discovery process
initiated when the NFC controller is up and running. For a given NFC
chipset there can be many configurations (embedded SE or not, with or
without a SIM card wired to the NFC controller SWP interface, etc...) and
thus driver code will never know before hand which SEs are available.
So we remove this field, it will be replaced by a real SE discovery
mechanism.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

When using NFC-F we should copy the NFCID2 buffer that we got from
SENSF_RES through the ATR_REQ NFCID3 buffer. Not doing so violates
NFC Forum digital requirement #189.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Before any operation, driver interruption is de-asserted to prevent
race condition between TX and RX.

Transaction starts by emitting "Direct read" and acknowledged mode
bytes. Then packet length is read allowing to allocate correct NCI
socket buffer. After that payload is retrieved.

A delay after the transaction can be added.
This delay is determined by the driver during nci_spi_allocate_device()
call and can be 0.

If acknowledged mode is set:
- CRC of header and payload is checked
- if frame reception fails (CRC error): NACK is sent
- if received frame has ACK or NACK flag: unblock nci_spi_send()

Payload is passed to NCI module.

At the end, driver interruption is re asserted.
Signed-off-by: NFrederic Danis <frederic.danis@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Before any operation, driver interruption is de-asserted to prevent
race condition between TX and RX.

The NCI over SPI header is added in front of NCI packet.
If acknowledged mode is set, CRC-16-CCITT is added to the packet.
Then the packet is forwarded to SPI module to be sent.

A delay after the transaction is added.
This delay is determined by the driver during nci_spi_allocate_device()
call and can be 0.

After data has been sent, driver interruption is re-asserted.

If acknowledged mode is set, nci_spi_send will block until
acknowledgment is received.
Signed-off-by: NFrederic Danis <frederic.danis@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The NFC Forum defines a transport interface based on
Serial Peripheral Interface (SPI) for the NFC Controller
Interface (NCI).

This module implements the SPI transport of NCI, calling SPI module
directly to read/write data to NFC controller (NFCC).

NFCC driver should provide functions performing device open and close.
It should also provide functions asserting/de-asserting interruption
to prevent TX/RX race conditions.
NFCC driver can also fix a delay between transactions if needed by
the hardware.
Signed-off-by: NFrederic Danis <frederic.danis@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This is a simple forward to the HCI driver. When driver is done with the
operation, it shall directly notify NFC Core by calling
nfc_fw_upload_done().
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

As several NFC chipsets can have their firmwares upgraded and
reflashed, this patchset adds a new netlink command to trigger
that the driver loads or flashes a new firmware. This will allows
userspace triggered firmware upgrade through netlink.
The firmware name or hint is passed as a parameter, and the driver
will eventually fetch the firmware binary through the request_firmware
API.
The cmd can only be executed when the nfc dev is not in use. Actual
firmware loading/flashing is an asynchronous operation. Result of the
operation shall send a new event up to user space through the nfc dev
multicast socket. During operation, the nfc dev is not openable and
thus not usable.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

skb->dev is used for carrying a net_device pointer and not
an nci_dev pointer.

Remove usage of skb-dev to carry nci_dev and replace it by parameter
in nci_recv_frame(), nci_send_frame() and driver send() functions.

NfcWilink driver is also updated to use those functions.
Signed-off-by: NFrederic Danis <frederic.danis@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

All NFC devices will now get proper RFKILL support as long as they provide
some dev_up and dev_down hooks. Rfkilling an NFC device will bring it down
while it is left to userspace to bring it back up when being rfkill unblocked.
This is very similar to what Bluetooth does.
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Each NFC adapter can have several links to different secure elements and
that property needs to be exported by the drivers.
A secure element link can be enabled and disabled, and card emulation will
be handled by the currently active one. Otherwise card emulation will be
host implemented.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Some chips diverge from the HCI spec in their implementation of standard
features. This adds a new quirks parameter to
nfc_hci_allocate_device() to let the driver indicate its divergence.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

There is no use to return an error if the caller doesn't get it.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

When an adapter is removed, it will unregister itself from hci and/or
nfc core. In order to do that safely, work tasks must first be canceled
and prevented to be scheduled again, before the hci or nfc device can be
destroyed.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Some HCI drivers will need it.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.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>

The driver now has all HCI stuff isolated in one file, and all the
hardware link specifics in another. Writing a pn544 driver on top of
another hardware link is now just a matter of adding a new file for that
new hardware specifics.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

And implement the corresponding hooks for pn544.
Signed-off-by: NArron Wang <arron.wang@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

And implement the corresponding hooks for pn544.
Signed-off-by: NArron Wang <arron.wang@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NArron Wang <arron.wang@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Set the local general bytes and default value for NFCIP1
Target/Initiator registries if the protocol is NFC-DEP
Signed-off-by: NArron Wang <arron.wang@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

xmit callback provided by a driver encapsulates upper layers
data and sends it to the hardware. So, HCI does not know the
exact amount of data being sent and thus can't handle partially
sent frames properly.

Therefore, the driver must return 0 for completely sent frame or
negative for failure.
Signed-off-by: NWaldemar Rymarkiewicz <waldemar.rymarkiewicz@tieto.com>
Acked-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The previous shdlc HCI driver and its header are removed from the tree.
PN544 now registers directly with HCI and passes the name of the llc it
requires (shdlc).
HCI instantiation now allocates the required llc instance. The llc is
started when the HCI device is brought up.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This is used by HCI drivers such as the one for the pn544 which require
communications between HCI and the chip to use shdlc.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This is a passthrough llc. It can be used by HCI drivers that don't
need link layer control. HCI will then write directly to the driver, and
driver will deliver incoming frames directly to HCI without any
processing.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The LLC layer manages modules that control the link layer protocol (such
as shdlc) between HCI and an HCI driver. The driver must simply specify
the required llc when it registers with HCI.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This enables the completion callback to be called from a different
context, preventing a possible deadlock if the callback resulted in the
invocation of a nested call to the currently locked nfc_dev.
This is also more in line with the im_transceive nfc_ops for NFC Core or
NCI drivers which already behave asynchronously.
Signed-off-by: NEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>