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-rw-r--r--include/net/caif/caif_layer.h279
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diff --git a/include/net/caif/caif_layer.h b/include/net/caif/caif_layer.h
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+++ b/include/net/caif/caif_layer.h
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) ST-Ericsson AB 2010
+ * Author: Sjur Brendeland
+ */
+
+#ifndef CAIF_LAYER_H_
+#define CAIF_LAYER_H_
+
+#include <linux/list.h>
+
+struct cflayer;
+struct cfpkt;
+struct cfpktq;
+struct caif_payload_info;
+struct caif_packet_funcs;
+
+#define CAIF_LAYER_NAME_SZ 16
+
+/**
+ * caif_assert() - Assert function for CAIF.
+ * @assert: expression to evaluate.
+ *
+ * This function will print a error message and a do WARN_ON if the
+ * assertion failes. Normally this will do a stack up at the current location.
+ */
+#define caif_assert(assert) \
+do { \
+ if (!(assert)) { \
+ pr_err("caif:Assert detected:'%s'\n", #assert); \
+ WARN_ON(!(assert)); \
+ } \
+} while (0)
+
+/**
+ * enum caif_ctrlcmd - CAIF Stack Control Signaling sent in layer.ctrlcmd().
+ *
+ * @CAIF_CTRLCMD_FLOW_OFF_IND: Flow Control is OFF, transmit function
+ * should stop sending data
+ *
+ * @CAIF_CTRLCMD_FLOW_ON_IND: Flow Control is ON, transmit function
+ * can start sending data
+ *
+ * @CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND: Remote end modem has decided to close
+ * down channel
+ *
+ * @CAIF_CTRLCMD_INIT_RSP: Called initially when the layer below
+ * has finished initialization
+ *
+ * @CAIF_CTRLCMD_DEINIT_RSP: Called when de-initialization is
+ * complete
+ *
+ * @CAIF_CTRLCMD_INIT_FAIL_RSP: Called if initialization fails
+ *
+ * @_CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND: CAIF Link layer temporarily cannot
+ * send more packets.
+ * @_CAIF_CTRLCMD_PHYIF_FLOW_ON_IND: Called if CAIF Link layer is able
+ * to send packets again.
+ * @_CAIF_CTRLCMD_PHYIF_DOWN_IND: Called if CAIF Link layer is going
+ * down.
+ *
+ * These commands are sent upwards in the CAIF stack to the CAIF Client.
+ * They are used for signaling originating from the modem or CAIF Link Layer.
+ * These are either responses (*_RSP) or events (*_IND).
+ */
+enum caif_ctrlcmd {
+ CAIF_CTRLCMD_FLOW_OFF_IND,
+ CAIF_CTRLCMD_FLOW_ON_IND,
+ CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND,
+ CAIF_CTRLCMD_INIT_RSP,
+ CAIF_CTRLCMD_DEINIT_RSP,
+ CAIF_CTRLCMD_INIT_FAIL_RSP,
+ _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND,
+ _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND,
+ _CAIF_CTRLCMD_PHYIF_DOWN_IND,
+};
+
+/**
+ * enum caif_modemcmd - Modem Control Signaling, sent from CAIF Client
+ * to the CAIF Link Layer or modem.
+ *
+ * @CAIF_MODEMCMD_FLOW_ON_REQ: Flow Control is ON, transmit function
+ * can start sending data.
+ *
+ * @CAIF_MODEMCMD_FLOW_OFF_REQ: Flow Control is OFF, transmit function
+ * should stop sending data.
+ *
+ * @_CAIF_MODEMCMD_PHYIF_USEFULL: Notify physical layer that it is in use
+ *
+ * @_CAIF_MODEMCMD_PHYIF_USELESS: Notify physical layer that it is
+ * no longer in use.
+ *
+ * These are requests sent 'downwards' in the stack.
+ * Flow ON, OFF can be indicated to the modem.
+ */
+enum caif_modemcmd {
+ CAIF_MODEMCMD_FLOW_ON_REQ = 0,
+ CAIF_MODEMCMD_FLOW_OFF_REQ = 1,
+ _CAIF_MODEMCMD_PHYIF_USEFULL = 3,
+ _CAIF_MODEMCMD_PHYIF_USELESS = 4
+};
+
+/**
+ * enum caif_direction - CAIF Packet Direction.
+ * Indicate if a packet is to be sent out or to be received in.
+ * @CAIF_DIR_IN: Incoming packet received.
+ * @CAIF_DIR_OUT: Outgoing packet to be transmitted.
+ */
+enum caif_direction {
+ CAIF_DIR_IN = 0,
+ CAIF_DIR_OUT = 1
+};
+
+/**
+ * struct cflayer - CAIF Stack layer.
+ * Defines the framework for the CAIF Core Stack.
+ * @up: Pointer up to the layer above.
+ * @dn: Pointer down to the layer below.
+ * @node: List node used when layer participate in a list.
+ * @receive: Packet receive function.
+ * @transmit: Packet transmit funciton.
+ * @ctrlcmd: Used for control signalling upwards in the stack.
+ * @modemcmd: Used for control signaling downwards in the stack.
+ * @id: The identity of this layer
+ * @name: Name of the layer.
+ *
+ * This structure defines the layered structure in CAIF.
+ *
+ * It defines CAIF layering structure, used by all CAIF Layers and the
+ * layers interfacing CAIF.
+ *
+ * In order to integrate with CAIF an adaptation layer on top of the CAIF stack
+ * and PHY layer below the CAIF stack
+ * must be implemented. These layer must follow the design principles below.
+ *
+ * Principles for layering of protocol layers:
+ * - All layers must use this structure. If embedding it, then place this
+ * structure first in the layer specific structure.
+ *
+ * - Each layer should not depend on any others layer's private data.
+ *
+ * - In order to send data upwards do
+ * layer->up->receive(layer->up, packet);
+ *
+ * - In order to send data downwards do
+ * layer->dn->transmit(layer->dn, info, packet);
+ */
+struct cflayer {
+ struct cflayer *up;
+ struct cflayer *dn;
+ struct list_head node;
+
+ /*
+ * receive() - Receive Function (non-blocking).
+ * Contract: Each layer must implement a receive function passing the
+ * CAIF packets upwards in the stack.
+ * Packet handling rules:
+ * - The CAIF packet (cfpkt) ownership is passed to the
+ * called receive function. This means that the
+ * packet cannot be accessed after passing it to the
+ * above layer using up->receive().
+ *
+ * - If parsing of the packet fails, the packet must be
+ * destroyed and negative error code returned
+ * from the function.
+ * EXCEPTION: If the framing layer (cffrml) returns
+ * -EILSEQ, the packet is not freed.
+ *
+ * - If parsing succeeds (and above layers return OK) then
+ * the function must return a value >= 0.
+ *
+ * Returns result < 0 indicates an error, 0 or positive value
+ * indicates success.
+ *
+ * @layr: Pointer to the current layer the receive function is
+ * implemented for (this pointer).
+ * @cfpkt: Pointer to CaifPacket to be handled.
+ */
+ int (*receive)(struct cflayer *layr, struct cfpkt *cfpkt);
+
+ /*
+ * transmit() - Transmit Function (non-blocking).
+ * Contract: Each layer must implement a transmit function passing the
+ * CAIF packet downwards in the stack.
+ * Packet handling rules:
+ * - The CAIF packet (cfpkt) ownership is passed to the
+ * transmit function. This means that the packet
+ * cannot be accessed after passing it to the below
+ * layer using dn->transmit().
+ *
+ * - Upon error the packet ownership is still passed on,
+ * so the packet shall be freed where error is detected.
+ * Callers of the transmit function shall not free packets,
+ * but errors shall be returned.
+ *
+ * - Return value less than zero means error, zero or
+ * greater than zero means OK.
+ *
+ * Returns result < 0 indicates an error, 0 or positive value
+ * indicates success.
+ *
+ * @layr: Pointer to the current layer the receive function
+ * isimplemented for (this pointer).
+ * @cfpkt: Pointer to CaifPacket to be handled.
+ */
+ int (*transmit) (struct cflayer *layr, struct cfpkt *cfpkt);
+
+ /*
+ * cttrlcmd() - Control Function upwards in CAIF Stack (non-blocking).
+ * Used for signaling responses (CAIF_CTRLCMD_*_RSP)
+ * and asynchronous events from the modem (CAIF_CTRLCMD_*_IND)
+ *
+ * @layr: Pointer to the current layer the receive function
+ * is implemented for (this pointer).
+ * @ctrl: Control Command.
+ */
+ void (*ctrlcmd) (struct cflayer *layr, enum caif_ctrlcmd ctrl,
+ int phyid);
+
+ /*
+ * modemctrl() - Control Function used for controlling the modem.
+ * Used to signal down-wards in the CAIF stack.
+ * Returns 0 on success, < 0 upon failure.
+ *
+ * @layr: Pointer to the current layer the receive function
+ * is implemented for (this pointer).
+ * @ctrl: Control Command.
+ */
+ int (*modemcmd) (struct cflayer *layr, enum caif_modemcmd ctrl);
+
+ unsigned int id;
+ char name[CAIF_LAYER_NAME_SZ];
+};
+
+/**
+ * layer_set_up() - Set the up pointer for a specified layer.
+ * @layr: Layer where up pointer shall be set.
+ * @above: Layer above.
+ */
+#define layer_set_up(layr, above) ((layr)->up = (struct cflayer *)(above))
+
+/**
+ * layer_set_dn() - Set the down pointer for a specified layer.
+ * @layr: Layer where down pointer shall be set.
+ * @below: Layer below.
+ */
+#define layer_set_dn(layr, below) ((layr)->dn = (struct cflayer *)(below))
+
+/**
+ * struct dev_info - Physical Device info information about physical layer.
+ * @dev: Pointer to native physical device.
+ * @id: Physical ID of the physical connection used by the
+ * logical CAIF connection. Used by service layers to
+ * identify their physical id to Caif MUX (CFMUXL)so
+ * that the MUX can add the correct physical ID to the
+ * packet.
+ */
+struct dev_info {
+ void *dev;
+ unsigned int id;
+};
+
+/**
+ * struct caif_payload_info - Payload information embedded in packet (sk_buff).
+ *
+ * @dev_info: Information about the receiving device.
+ *
+ * @hdr_len: Header length, used to align pay load on 32bit boundary.
+ *
+ * @channel_id: Channel ID of the logical CAIF connection.
+ * Used by mux to insert channel id into the caif packet.
+ */
+struct caif_payload_info {
+ struct dev_info *dev_info;
+ unsigned short hdr_len;
+ unsigned short channel_id;
+};
+
+#endif /* CAIF_LAYER_H_ */