modem: Add M6718 IPC SPI driver protocol framework

Adds the M6718 modem IPC SPI driver procotol framework and types.
Placeholders remain where future parts of the protocol will be
called.

ST-Ericsson ID: 369397
ST-Ericsson FOSS-OUT ID: STETL-FOSS-OUT-12224
ST-Ericsson Linux next: NA

Change-Id: Id4cd5a7fa730c06838c9dd5b1a1cc0045135fdd4
Signed-off-by: Chris Blair <chris.blair@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/36466
Reviewed-by: QATOOLS
Reviewed-by: QABUILD
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>

8 files changed, 548 insertions, 4 deletions

diff --git a/drivers/modem/m6718_spi/Makefile b/drivers/modem/m6718_spi/Makefile
index 492995bc753..66bad09c0dd 100644
--- a/drivers/modem/m6718_spi/Makefile
+++ b/drivers/modem/m6718_spi/Makefile
@@ -5,7 +5,7 @@ ifeq ($(CONFIG_MODEM_M6718_SPI_DEBUG),y)
 EXTRA_CFLAGS += -DDEBUG
 endif
 
-m6718_modem_spi-objs := modem_driver.o
+m6718_modem_spi-objs := modem_driver.o protocol.o
 
 ifeq ($(CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_MODEM_STATE),y)
 m6718_modem_spi-objs += modem_state.o
diff --git a/drivers/modem/m6718_spi/modem_driver.c b/drivers/modem/m6718_spi/modem_driver.c
index 7d0efa6e395..13d4a3e28b2 100644
--- a/drivers/modem/m6718_spi/modem_driver.c
+++ b/drivers/modem/m6718_spi/modem_driver.c
@@ -13,6 +13,7 @@
 #include <linux/spi/spi.h>
 #include <linux/modem/modem_client.h>
 #include <linux/modem/m6718_spi/modem_driver.h>
+#include "modem_protocol.h"
 
 static struct modem_spi_dev modem_driver_data = {
 	.dev = NULL,
@@ -53,6 +54,13 @@ static int spi_probe(struct spi_device *sdev)
 
 	spi_set_drvdata(sdev, &modem_driver_data);
 
+	if (modem_protocol_probe(sdev) != 0) {
+		dev_err(&sdev->dev,
+			"failed to initialise link protocol\n");
+		result = -ENODEV;
+		goto rollback;
+	}
+
 	/*
 	 * Since we can have multiple spi links for the same modem, only
 	 * initialise the modem data and char/net interfaces once.
@@ -65,13 +73,20 @@ static int spi_probe(struct spi_device *sdev)
 			dev_err(&sdev->dev,
 				"failed to retrieve modem description\n");
 			result = -ENODEV;
+			goto rollback_protocol_init;
 		}
 	}
 	return result;
+
+rollback_protocol_init:
+	modem_protocol_exit();
+rollback:
+	return result;
 }
 
 static int __exit spi_remove(struct spi_device *sdev)
 {
+	modem_protocol_exit();
 	return 0;
 }
 
@@ -86,8 +101,14 @@ static int __exit spi_remove(struct spi_device *sdev)
  */
 static int spi_suspend(struct spi_device *sdev, pm_message_t mesg)
 {
-	dev_dbg(&sdev->dev, "suspend called\n");
-	return 0;
+	bool busy;
+
+	busy = modem_protocol_is_busy(sdev);
+	dev_dbg(&sdev->dev, "suspend called, protocol busy:%d\n", busy);
+	if (!busy)
+		return 0;
+	else
+		return -EBUSY;
 }
 
 /**
@@ -118,6 +139,7 @@ static struct spi_driver spi_driver = {
 static int __init m6718_spi_driver_init(void)
 {
 	pr_info("M6718 modem driver initialising\n");
+	modem_protocol_init();
 	return spi_register_driver(&spi_driver);
 }
 module_init(m6718_spi_driver_init);
diff --git a/drivers/modem/m6718_spi/modem_private.h b/drivers/modem/m6718_spi/modem_private.h
new file mode 100644
index 00000000000..383699f1f3e
--- /dev/null
+++ b/drivers/modem/m6718_spi/modem_private.h
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2011
+ *
+ * Author: Chris Blair <chris.blair@stericsson.com> for ST-Ericsson
+ *   based on shrm_driver.h
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ * Modem IPC driver protocol interface header:
+ *   private data
+ */
+#ifndef _MODEM_PRIVATE_H_
+#define _MODEM_PRIVATE_H_
+
+#include <linux/kernel.h>
+#include <linux/spi/spi.h>
+#include <linux/atomic.h>
+#include <linux/interrupt.h>
+#include <linux/timer.h>
+#include <linux/list.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/uaccess.h>
+#include "modem_protocol.h"
+#include "modem_statemachine.h"
+
+#define IPC_DRIVER_VERSION       (0x03) /* APE protocol version */
+#define IPC_DRIVER_MODEM_MIN_VER (0x03) /* version required from modem */
+
+#define IPC_NBR_SUPPORTED_SPI_LINKS (2)
+#define IPC_LINK_COMMON (0)
+#define IPC_LINK_AUDIO  (1)
+
+#define IPC_TX_QUEUE_MAX_SIZE (1024*1024)
+
+#define IPC_L1_HDR_SIZE (4)
+#define IPC_L2_HDR_SIZE (4)
+
+/* tx queue item (frame) */
+struct ipc_tx_queue {
+	struct list_head node;
+	int actual_len;
+	int len;
+	void *data;
+	int counter;
+};
+
+/* context structure for an spi link */
+struct ipc_link_context {
+	struct modem_m6718_spi_link_platform_data *link;
+	struct spi_device *sdev;
+	atomic_t gpio_configured;
+	atomic_t state_int;
+	spinlock_t sm_lock;
+	spinlock_t tx_q_update_lock;
+	atomic_t tx_q_count;
+	int tx_q_free;
+	struct list_head tx_q;
+	int tx_frame_counter;
+	const struct ipc_sm_state *state;
+	u32 cmd;
+	struct ipc_tx_queue *frame;
+	struct spi_message spi_message;
+	struct spi_transfer spi_transfer;
+	struct timer_list comms_timer;
+	struct timer_list slave_stable_timer;
+#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_VERIFY_FRAMES
+	struct ipc_tx_queue *last_frame;
+#endif
+#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_THROUGHPUT_MEASUREMENT
+	u32 tx_bytes;
+	u32 rx_bytes;
+	unsigned long idl_measured_at;
+	unsigned long idl_idle_enter;
+	unsigned long idl_idle_total;
+#endif
+#ifdef CONFIG_DEBUG_FS
+	struct dentry *debugfsfile;
+	u8 lastevent;
+	u8 lastignored;
+	enum ipc_sm_state_id lastignored_in;
+	bool lastignored_inthis;
+	int tx_q_min;
+	unsigned long statesince;
+#endif
+};
+
+/* context structure for the spi driver */
+struct ipc_l1_context {
+	bool init_done;
+	atomic_t boot_sync_done;
+	struct ipc_link_context device_context[IPC_NBR_SUPPORTED_SPI_LINKS];
+#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_THROUGHPUT_MEASUREMENT
+	struct timer_list tp_timer;
+#endif
+#ifdef CONFIG_DEBUG_FS
+	struct dentry *debugfsdir;
+	struct dentry *debugfs_silentreset;
+	bool msr_disable;
+#endif
+};
+
+#endif /* _MODEM_PRIVATE_H_ */
diff --git a/drivers/modem/m6718_spi/modem_protocol.h b/drivers/modem/m6718_spi/modem_protocol.h
new file mode 100644
index 00000000000..69511945cb5
--- /dev/null
+++ b/drivers/modem/m6718_spi/modem_protocol.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2011
+ *
+ * Author: Chris Blair <chris.blair@stericsson.com> for ST-Ericsson
+ *   based on shrm_driver.h
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ * Modem IPC driver protocol interface header.
+ */
+#ifndef _MODEM_PROTOCOL_H_
+#define _MODEM_PROTOCOL_H_
+
+#include <linux/spi/spi.h>
+
+void modem_protocol_init(void);
+int modem_protocol_probe(struct spi_device *sdev);
+void modem_protocol_exit(void);
+bool modem_protocol_is_busy(struct spi_device *sdev);
+bool modem_protocol_channel_is_open(u8 channel);
+
+#endif /* _MODEM_PROTOCOL_H_ */
diff --git a/drivers/modem/m6718_spi/modem_state.c b/drivers/modem/m6718_spi/modem_state.c
index 266f75a7a71..47376934bcb 100644
--- a/drivers/modem/m6718_spi/modem_state.c
+++ b/drivers/modem/m6718_spi/modem_state.c
@@ -13,7 +13,6 @@
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/wait.h>
-#include <linux/modem/m6718_spi/modem_state.h>
 #include <linux/gpio.h>
 #include <linux/interrupt.h>
 #include <linux/ioport.h>
@@ -30,6 +29,7 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/uaccess.h>
+#include "modem_state.h"
 
 /*
  * To enable this driver add a struct platform_device in the board
diff --git a/drivers/modem/m6718_spi/modem_state.h b/drivers/modem/m6718_spi/modem_state.h
new file mode 100644
index 00000000000..a2f1d9fbe3e
--- /dev/null
+++ b/drivers/modem/m6718_spi/modem_state.h
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2011
+ *
+ * Author: Derek Morton <derek.morton@stericsson.com>
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ * Power state driver for M6718 MODEM
+ */
+#ifndef MODEM_STATE_H
+#define MODEM_STATE_H
+
+enum modem_states {
+	MODEM_STATE_OFF,
+	MODEM_STATE_RESET,
+	MODEM_STATE_CRASH,
+	MODEM_STATE_ON,
+	/*
+	 * Add new states before end marker and update modem_state_str[]
+	 * in modem_state.c
+	 */
+	MODEM_STATE_END_MARKER
+};
+
+void modem_state_power_on(void);
+void modem_state_power_off(void);
+void modem_state_force_reset(void);
+int modem_state_get_state(void);
+char *modem_state_to_str(int state);
+
+/* Callbacks will be running in tasklet context */
+int modem_state_register_callback(int (*callback) (unsigned long),
+	unsigned long data);
+int modem_state_remove_callback(int (*callback) (unsigned long));
+
+#endif
diff --git a/drivers/modem/m6718_spi/modem_statemachine.h b/drivers/modem/m6718_spi/modem_statemachine.h
new file mode 100644
index 00000000000..bc737dbb7e8
--- /dev/null
+++ b/drivers/modem/m6718_spi/modem_statemachine.h
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2011
+ *
+ * Author: Chris Blair <chris.blair@stericsson.com> for ST-Ericsson
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ * Modem IPC driver protocol interface header:
+ *   statemachine functionality.
+ */
+#ifndef _MODEM_STATEMACHINE_H_
+#define _MODEM_STATEMACHINE_H_
+
+#include <linux/kernel.h>
+
+/* valid states for the driver state machine */
+enum ipc_sm_state_id {
+	/* common link and shared states below */
+	IPC_SM_INIT,
+	IPC_SM_HALT,
+	IPC_SM_RESET,
+	IPC_SM_WAIT_SLAVE_STABLE,
+	IPC_SM_WAIT_HANDSHAKE_INACTIVE,
+	IPC_SM_SLW_TX_BOOTREQ,
+	IPC_SM_ACT_TX_BOOTREQ,
+	IPC_SM_SLW_RX_BOOTRESP,
+	IPC_SM_ACT_RX_BOOTRESP,
+	IPC_SM_IDL,
+	IPC_SM_SLW_TX_WR_CMD,
+	IPC_SM_ACT_TX_WR_CMD,
+	IPC_SM_SLW_TX_WR_DAT,
+	IPC_SM_ACT_TX_WR_DAT,
+	IPC_SM_SLW_TX_RD_CMD,
+	IPC_SM_ACT_TX_RD_CMD,
+	IPC_SM_SLW_RX_WR_CMD,
+	IPC_SM_ACT_RX_WR_CMD,
+	IPC_SM_ACT_RX_WR_DAT,
+	/* audio link states below */
+	IPC_SM_INIT_AUD,
+	IPC_SM_HALT_AUD,
+	IPC_SM_RESET_AUD,
+	IPC_SM_IDL_AUD,
+	IPC_SM_SLW_TX_WR_DAT_AUD,
+	IPC_SM_ACT_TX_WR_DAT_AUD,
+	IPC_SM_SLW_RX_WR_DAT_AUD,
+	IPC_SM_ACT_RX_WR_DAT_AUD,
+	IPC_SM_STATE_ID_NBR
+};
+
+/* state machine trigger causes events */
+#define IPC_SM_RUN_NONE         (0x00)
+#define IPC_SM_RUN_SLAVE_IRQ    (0x01)
+#define IPC_SM_RUN_TFR_COMPLETE (0x02)
+#define IPC_SM_RUN_TX_REQ       (0x04)
+#define IPC_SM_RUN_INIT         (0x08)
+#define IPC_SM_RUN_ABORT        (0x10)
+#define IPC_SM_RUN_COMMS_TMO    (0x20)
+#define IPC_SM_RUN_STABLE_TMO   (0x40)
+#define IPC_SM_RUN_RESET        (0x80)
+
+struct ipc_link_context; /* forward declaration */
+
+typedef u8 (*ipc_sm_enter_func)(u8 event, struct ipc_link_context *context);
+typedef const struct ipc_sm_state *(*ipc_sm_exit_func)(u8 event,
+					struct ipc_link_context *context);
+
+struct ipc_sm_state {
+	enum ipc_sm_state_id id;
+	ipc_sm_enter_func enter;
+	ipc_sm_exit_func exit;
+	u8 events;
+};
+
+#endif /* _MODEM_STATEMACHINE_H_ */
diff --git a/drivers/modem/m6718_spi/protocol.c b/drivers/modem/m6718_spi/protocol.c
new file mode 100644
index 00000000000..5f03167d024
--- /dev/null
+++ b/drivers/modem/m6718_spi/protocol.c
@@ -0,0 +1,287 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010,2011
+ *
+ * Author: Chris Blair <chris.blair@stericsson.com> for ST-Ericsson
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ * U9500 <-> M6718 IPC protocol implementation using SPI.
+ */
+#include <linux/modem/m6718_spi/modem_driver.h>
+#include "modem_protocol.h"
+#include "modem_private.h"
+
+#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_MODEM_STATE
+#include <linux/workqueue.h>
+#include "modem_state.h"
+
+#define MODEM_STATE_REGISTER_TMO_MS  (500)
+#endif
+
+#ifdef WORKAROUND_DUPLICATED_IRQ
+#include <linux/amba/pl022.h>
+#endif
+
+struct l2mux_channel {
+	u8 open:1;
+	u8 link:7;
+};
+
+/* valid open L2 mux channels */
+static const struct l2mux_channel channels[255] = {
+	[MODEM_M6718_SPI_CHN_ISI] = {
+		.open = true,
+		.link = IPC_LINK_COMMON
+	},
+	[MODEM_M6718_SPI_CHN_AUDIO] = {
+		.open = true,
+		.link = IPC_LINK_AUDIO
+	},
+	[MODEM_M6718_SPI_CHN_MASTER_LOOPBACK0] = {
+		.open = true,
+		.link = IPC_LINK_COMMON
+	},
+	[MODEM_M6718_SPI_CHN_SLAVE_LOOPBACK0] = {
+		.open = true,
+		.link = IPC_LINK_COMMON
+	},
+	[MODEM_M6718_SPI_CHN_MASTER_LOOPBACK1] = {
+		.open = true,
+		.link = IPC_LINK_AUDIO
+	},
+	[MODEM_M6718_SPI_CHN_SLAVE_LOOPBACK1] = {
+		.open = true,
+		.link = IPC_LINK_AUDIO
+	}
+};
+
+#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_MODEM_STATE
+static void modem_state_reg_wq(struct work_struct *work);
+static DECLARE_DELAYED_WORK(modem_state_reg_work, modem_state_reg_wq);
+#endif
+
+/* the spi driver context */
+struct ipc_l1_context l1_context = {
+#ifdef CONFIG_DEBUG_FS
+	.msr_disable = false,
+#endif
+	.init_done = false
+};
+
+bool modem_protocol_channel_is_open(u8 channel)
+{
+	return channels[channel].open;
+}
+
+void modem_comms_timeout(unsigned long data)
+{
+	/* TODO: statemachine will be kicked here */
+}
+
+void slave_stable_timeout(unsigned long data)
+{
+	/* TODO: statemachine will be kicked here */
+}
+
+/**
+ * modem_protocol_init() - initialise the IPC protocol
+ *
+ * Initialises the IPC protocol in preparation for use. After this is called
+ * the protocol is ready to be probed for each link to be supported.
+ */
+void modem_protocol_init(void)
+{
+	pr_info("M6718 IPC protocol initialising version %02x\n",
+		IPC_DRIVER_VERSION);
+
+	atomic_set(&l1_context.boot_sync_done, 0);
+	l1_context.init_done = true;
+#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_MODEM_STATE
+	schedule_delayed_work(&modem_state_reg_work, 0);
+#endif
+}
+
+/**
+ * modem_m6718_spi_send() - send a frame using the IPC protocol
+ * @modem_spi_dev: pointer to modem driver information structure
+ * @channel:       L2 channel to send on
+ * @len:           length of data to send
+ * @data:          pointer to buffer containing data
+ *
+ * Check that the requested channel is supported and open, queue a frame
+ * containing the data on the appropriate link and ensure the state machine
+ * is running to start the transfer.
+ */
+int modem_m6718_spi_send(struct modem_spi_dev *modem_spi_dev, u8 channel,
+	u32 len, void *data)
+{
+	struct ipc_link_context *context;
+
+	if (!channels[channel].open) {
+		dev_err(modem_spi_dev->dev,
+			"error: invalid channel (%d), discarding frame\n",
+			channel);
+		return -EINVAL;
+	}
+
+	context = &l1_context.device_context[channels[channel].link];
+	if (context->state == NULL || context->state->id == IPC_SM_HALT) {
+		static unsigned long linkfail_warn_time;
+		if (printk_timed_ratelimit(&linkfail_warn_time, 60 * 1000))
+			dev_err(modem_spi_dev->dev,
+				"error: link %d for ch %d is not available, "
+				"discarding frames\n",
+				channels[channel].link, channel);
+		return -ENODEV;
+	}
+
+	/* TODO: statemachine will be kicked here */
+	return 0;
+}
+EXPORT_SYMBOL_GPL(modem_m6718_spi_send);
+
+/**
+ * modem_m6718_spi_is_boot_done() - check if boot handshake with modem is done
+ */
+bool modem_m6718_spi_is_boot_done(void)
+{
+	return atomic_read(&l1_context.boot_sync_done);
+}
+EXPORT_SYMBOL_GPL(modem_m6718_spi_is_boot_done);
+
+/**
+ * modem_protocol_is_busy() - check if the protocol is currently active
+ * @sdev: pointer to spi_device for link to check
+ *
+ * Checks each of the IPC links to see if they are inactive: this means they
+ * can be in either IDLE or INIT states. If any of the links are not idle then
+ * true is returned to indicate that the protocol is busy.
+ */
+bool modem_protocol_is_busy(struct spi_device *sdev)
+{
+	int i;
+
+	for (i = 0; i < IPC_NBR_SUPPORTED_SPI_LINKS; i++)
+		switch (l1_context.device_context[i].state->id) {
+		case IPC_SM_IDL:
+		case IPC_SM_IDL_AUD:
+		case IPC_SM_INIT:
+		case IPC_SM_INIT_AUD:
+		case IPC_SM_WAIT_SLAVE_STABLE:
+			/* not busy; continue checking */
+			break;
+		default:
+			dev_info(&sdev->dev, "link %d is busy\n", i);
+			return true;
+		}
+	return false;
+}
+
+#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_MODEM_STATE
+static int modem_state_callback(unsigned long unused)
+{
+	int modem_state = modem_state_get_state();
+
+	pr_info("M6718 IPC protocol modemstate reports modem is %s\n",
+		modem_state_to_str(modem_state));
+
+	switch (modem_state) {
+	case MODEM_STATE_ON:
+		/* TODO: statemachine will be kicked here */
+		break;
+	case MODEM_STATE_OFF:
+	case MODEM_STATE_RESET:
+	case MODEM_STATE_CRASH:
+		/* TODO: statemachine will be kicked here */
+		break;
+	default:
+		break;
+	}
+	return 0;
+}
+
+static void modem_state_reg_wq(struct work_struct *work)
+{
+	if (modem_state_register_callback(modem_state_callback, 0) == -EAGAIN) {
+		pr_info("M6718 IPC protocol failed to register with "
+			"modemstate, will retry\n");
+		schedule_delayed_work(&modem_state_reg_work,
+			(MODEM_STATE_REGISTER_TMO_MS * HZ) / 1000);
+	} else {
+		pr_info("M6718 IPC protocol registered with modemstate\n");
+	}
+}
+#endif
+
+int modem_protocol_probe(struct spi_device *sdev)
+{
+	struct modem_m6718_spi_link_platform_data *link =
+		sdev->dev.platform_data;
+	struct ipc_link_context *context;
+	int link_id;
+
+	if (link == NULL) {
+		/* platform data missing in board config? */
+		dev_err(&sdev->dev, "error: no platform data for link!\n");
+		return -ENODEV;
+	}
+
+	link_id = link->id;
+	context = &l1_context.device_context[link_id];
+
+	if (link_id >= IPC_NBR_SUPPORTED_SPI_LINKS) {
+		dev_err(&sdev->dev,
+			"link %d error: too many links! (max %d)\n",
+			link->id, IPC_NBR_SUPPORTED_SPI_LINKS);
+		return -ENODEV;
+	}
+
+	dev_info(&sdev->dev,
+		"link %d: registering SPI link bus:%d cs:%d\n",
+		link->id, sdev->master->bus_num, sdev->chip_select);
+
+	/* update spi device with correct word size for our device */
+	sdev->bits_per_word = 16;
+	spi_setup(sdev);
+
+	/* init link context */
+	context->link = link;
+	context->sdev = sdev;
+	atomic_set(&context->gpio_configured, 0);
+	spin_lock_init(&context->sm_lock);
+	init_timer(&context->comms_timer);
+	context->comms_timer.function = modem_comms_timeout;
+	context->comms_timer.data = (unsigned long)context;
+	init_timer(&context->slave_stable_timer);
+	context->slave_stable_timer.function = slave_stable_timeout;
+	context->slave_stable_timer.data = (unsigned long)context;
+
+#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_VERIFY_FRAMES
+	context->last_frame = NULL;
+#endif
+
+	/*
+	 * For link0 (the handshake link) we force a state transition now so
+	 * that it prepares for boot sync.
+	 */
+	/* TODO: statemachine will be kicked here */
+
+	/*
+	 * unlikely but possible: for links other than 0, check if handshake is
+	 * already complete by the time this link is probed - if so we force a
+	 * state transition since the one issued by the handshake exit actions
+	 * will have been ignored.
+	 */
+	if (link->id > 0 && atomic_read(&l1_context.boot_sync_done)) {
+		dev_dbg(&sdev->dev,
+			"link %d: boot sync is done, kicking state machine\n",
+			link->id);
+		/* TODO: statemachine will be kicked here */
+	}
+	return 0;
+}
+
+void modem_protocol_exit(void)
+{
+	pr_info("M6718 IPC protocol exit\n");
+}