soc: qcom: smd: Remove standalone driver

Remove the standalone SMD implementation as we have transitioned the
client drivers to use the RPMSG based one.

Also remove all dependencies on QCOM_SMD from Kconfig files, in order to
keep them selectable in the absence of the removed symbol.

Acked-by: Andy Gross <andy.gross@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 0 insertions, 1569 deletions

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index 4e090c697eb6..9fca977ef18d 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -33,14 +33,6 @@ config QCOM_SMEM
 	  The driver provides an interface to items in a heap shared among all
 	  processors in a Qualcomm platform.
 
-config QCOM_SMD
-	tristate "Qualcomm Shared Memory Driver (SMD)"
-	depends on QCOM_SMEM
-	help
-	  Say y here to enable support for the Qualcomm Shared Memory Driver
-	  providing communication channels to remote processors in Qualcomm
-	  platforms.
-
 config QCOM_SMD_RPM
 	tristate "Qualcomm Resource Power Manager (RPM) over SMD"
 	depends on ARCH_QCOM
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 1f30260b06b8..414f0de274fa 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -1,7 +1,6 @@
 obj-$(CONFIG_QCOM_GSBI)	+=	qcom_gsbi.o
 obj-$(CONFIG_QCOM_MDT_LOADER)	+= mdt_loader.o
 obj-$(CONFIG_QCOM_PM)	+=	spm.o
-obj-$(CONFIG_QCOM_SMD) +=	smd.o
 obj-$(CONFIG_QCOM_SMD_RPM)	+= smd-rpm.o
 obj-$(CONFIG_QCOM_SMEM) +=	smem.o
 obj-$(CONFIG_QCOM_SMEM_STATE) += smem_state.o
diff --git a/drivers/soc/qcom/smd.c b/drivers/soc/qcom/smd.c
deleted file mode 100644
index 322034ab9d37..000000000000
--- a/drivers/soc/qcom/smd.c
+++ /dev/null
@@ -1,1560 +0,0 @@
-/*
- * Copyright (c) 2015, Sony Mobile Communications AB.
- * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 and
- * only version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that 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.
- */
-
-#include <linux/interrupt.h>
-#include <linux/io.h>
-#include <linux/mfd/syscon.h>
-#include <linux/module.h>
-#include <linux/of_irq.h>
-#include <linux/of_platform.h>
-#include <linux/platform_device.h>
-#include <linux/regmap.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/soc/qcom/smd.h>
-#include <linux/soc/qcom/smem.h>
-#include <linux/wait.h>
-
-/*
- * The Qualcomm Shared Memory communication solution provides point-to-point
- * channels for clients to send and receive streaming or packet based data.
- *
- * Each channel consists of a control item (channel info) and a ring buffer
- * pair. The channel info carry information related to channel state, flow
- * control and the offsets within the ring buffer.
- *
- * All allocated channels are listed in an allocation table, identifying the
- * pair of items by name, type and remote processor.
- *
- * Upon creating a new channel the remote processor allocates channel info and
- * ring buffer items from the smem heap and populate the allocation table. An
- * interrupt is sent to the other end of the channel and a scan for new
- * channels should be done. A channel never goes away, it will only change
- * state.
- *
- * The remote processor signals it intent for bring up the communication
- * channel by setting the state of its end of the channel to "opening" and
- * sends out an interrupt. We detect this change and register a smd device to
- * consume the channel. Upon finding a consumer we finish the handshake and the
- * channel is up.
- *
- * Upon closing a channel, the remote processor will update the state of its
- * end of the channel and signal us, we will then unregister any attached
- * device and close our end of the channel.
- *
- * Devices attached to a channel can use the qcom_smd_send function to push
- * data to the channel, this is done by copying the data into the tx ring
- * buffer, updating the pointers in the channel info and signaling the remote
- * processor.
- *
- * The remote processor does the equivalent when it transfer data and upon
- * receiving the interrupt we check the channel info for new data and delivers
- * this to the attached device. If the device is not ready to receive the data
- * we leave it in the ring buffer for now.
- */
-
-struct smd_channel_info;
-struct smd_channel_info_pair;
-struct smd_channel_info_word;
-struct smd_channel_info_word_pair;
-
-#define SMD_ALLOC_TBL_COUNT	2
-#define SMD_ALLOC_TBL_SIZE	64
-
-/*
- * This lists the various smem heap items relevant for the allocation table and
- * smd channel entries.
- */
-static const struct {
-	unsigned alloc_tbl_id;
-	unsigned info_base_id;
-	unsigned fifo_base_id;
-} smem_items[SMD_ALLOC_TBL_COUNT] = {
-	{
-		.alloc_tbl_id = 13,
-		.info_base_id = 14,
-		.fifo_base_id = 338
-	},
-	{
-		.alloc_tbl_id = 266,
-		.info_base_id = 138,
-		.fifo_base_id = 202,
-	},
-};
-
-/**
- * struct qcom_smd_edge - representing a remote processor
- * @dev:		device for this edge
- * @of_node:		of_node handle for information related to this edge
- * @edge_id:		identifier of this edge
- * @remote_pid:		identifier of remote processor
- * @irq:		interrupt for signals on this edge
- * @ipc_regmap:		regmap handle holding the outgoing ipc register
- * @ipc_offset:		offset within @ipc_regmap of the register for ipc
- * @ipc_bit:		bit in the register at @ipc_offset of @ipc_regmap
- * @channels:		list of all channels detected on this edge
- * @channels_lock:	guard for modifications of @channels
- * @allocated:		array of bitmaps representing already allocated channels
- * @smem_available:	last available amount of smem triggering a channel scan
- * @scan_work:		work item for discovering new channels
- * @state_work:		work item for edge state changes
- */
-struct qcom_smd_edge {
-	struct device dev;
-
-	struct device_node *of_node;
-	unsigned edge_id;
-	unsigned remote_pid;
-
-	int irq;
-
-	struct regmap *ipc_regmap;
-	int ipc_offset;
-	int ipc_bit;
-
-	struct list_head channels;
-	spinlock_t channels_lock;
-
-	DECLARE_BITMAP(allocated[SMD_ALLOC_TBL_COUNT], SMD_ALLOC_TBL_SIZE);
-
-	unsigned smem_available;
-
-	wait_queue_head_t new_channel_event;
-
-	struct work_struct scan_work;
-	struct work_struct state_work;
-};
-
-#define to_smd_edge(d) container_of(d, struct qcom_smd_edge, dev)
-
-/*
- * SMD channel states.
- */
-enum smd_channel_state {
-	SMD_CHANNEL_CLOSED,
-	SMD_CHANNEL_OPENING,
-	SMD_CHANNEL_OPENED,
-	SMD_CHANNEL_FLUSHING,
-	SMD_CHANNEL_CLOSING,
-	SMD_CHANNEL_RESET,
-	SMD_CHANNEL_RESET_OPENING
-};
-
-/**
- * struct qcom_smd_channel - smd channel struct
- * @edge:		qcom_smd_edge this channel is living on
- * @qsdev:		reference to a associated smd client device
- * @name:		name of the channel
- * @state:		local state of the channel
- * @remote_state:	remote state of the channel
- * @info:		byte aligned outgoing/incoming channel info
- * @info_word:		word aligned outgoing/incoming channel info
- * @tx_lock:		lock to make writes to the channel mutually exclusive
- * @fblockread_event:	wakeup event tied to tx fBLOCKREADINTR
- * @tx_fifo:		pointer to the outgoing ring buffer
- * @rx_fifo:		pointer to the incoming ring buffer
- * @fifo_size:		size of each ring buffer
- * @bounce_buffer:	bounce buffer for reading wrapped packets
- * @cb:			callback function registered for this channel
- * @recv_lock:		guard for rx info modifications and cb pointer
- * @pkt_size:		size of the currently handled packet
- * @list:		lite entry for @channels in qcom_smd_edge
- */
-struct qcom_smd_channel {
-	struct qcom_smd_edge *edge;
-
-	struct qcom_smd_device *qsdev;
-
-	char *name;
-	enum smd_channel_state state;
-	enum smd_channel_state remote_state;
-
-	struct smd_channel_info_pair *info;
-	struct smd_channel_info_word_pair *info_word;
-
-	struct mutex tx_lock;
-	wait_queue_head_t fblockread_event;
-
-	void *tx_fifo;
-	void *rx_fifo;
-	int fifo_size;
-
-	void *bounce_buffer;
-	qcom_smd_cb_t cb;
-
-	spinlock_t recv_lock;
-
-	int pkt_size;
-
-	void *drvdata;
-
-	struct list_head list;
-};
-
-/*
- * Format of the smd_info smem items, for byte aligned channels.
- */
-struct smd_channel_info {
-	__le32 state;
-	u8  fDSR;
-	u8  fCTS;
-	u8  fCD;
-	u8  fRI;
-	u8  fHEAD;
-	u8  fTAIL;
-	u8  fSTATE;
-	u8  fBLOCKREADINTR;
-	__le32 tail;
-	__le32 head;
-};
-
-struct smd_channel_info_pair {
-	struct smd_channel_info tx;
-	struct smd_channel_info rx;
-};
-
-/*
- * Format of the smd_info smem items, for word aligned channels.
- */
-struct smd_channel_info_word {
-	__le32 state;
-	__le32 fDSR;
-	__le32 fCTS;
-	__le32 fCD;
-	__le32 fRI;
-	__le32 fHEAD;
-	__le32 fTAIL;
-	__le32 fSTATE;
-	__le32 fBLOCKREADINTR;
-	__le32 tail;
-	__le32 head;
-};
-
-struct smd_channel_info_word_pair {
-	struct smd_channel_info_word tx;
-	struct smd_channel_info_word rx;
-};
-
-#define GET_RX_CHANNEL_FLAG(channel, param)				     \
-	({								     \
-		BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u8)); \
-		channel->info_word ?					     \
-			le32_to_cpu(channel->info_word->rx.param) :	     \
-			channel->info->rx.param;			     \
-	})
-
-#define GET_RX_CHANNEL_INFO(channel, param)				      \
-	({								      \
-		BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u32)); \
-		le32_to_cpu(channel->info_word ?			      \
-			channel->info_word->rx.param :			      \
-			channel->info->rx.param);			      \
-	})
-
-#define SET_RX_CHANNEL_FLAG(channel, param, value)			     \
-	({								     \
-		BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u8)); \
-		if (channel->info_word)					     \
-			channel->info_word->rx.param = cpu_to_le32(value);   \
-		else							     \
-			channel->info->rx.param = value;		     \
-	})
-
-#define SET_RX_CHANNEL_INFO(channel, param, value)			      \
-	({								      \
-		BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u32)); \
-		if (channel->info_word)					      \
-			channel->info_word->rx.param = cpu_to_le32(value);    \
-		else							      \
-			channel->info->rx.param = cpu_to_le32(value);	      \
-	})
-
-#define GET_TX_CHANNEL_FLAG(channel, param)				     \
-	({								     \
-		BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u8)); \
-		channel->info_word ?					     \
-			le32_to_cpu(channel->info_word->tx.param) :          \
-			channel->info->tx.param;			     \
-	})
-
-#define GET_TX_CHANNEL_INFO(channel, param)				      \
-	({								      \
-		BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u32)); \
-		le32_to_cpu(channel->info_word ?			      \
-			channel->info_word->tx.param :			      \
-			channel->info->tx.param);			      \
-	})
-
-#define SET_TX_CHANNEL_FLAG(channel, param, value)			     \
-	({								     \
-		BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u8)); \
-		if (channel->info_word)					     \
-			channel->info_word->tx.param = cpu_to_le32(value);   \
-		else							     \
-			channel->info->tx.param = value;		     \
-	})
-
-#define SET_TX_CHANNEL_INFO(channel, param, value)			      \
-	({								      \
-		BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u32)); \
-		if (channel->info_word)					      \
-			channel->info_word->tx.param = cpu_to_le32(value);   \
-		else							      \
-			channel->info->tx.param = cpu_to_le32(value);	      \
-	})
-
-/**
- * struct qcom_smd_alloc_entry - channel allocation entry
- * @name:	channel name
- * @cid:	channel index
- * @flags:	channel flags and edge id
- * @ref_count:	reference count of the channel
- */
-struct qcom_smd_alloc_entry {
-	u8 name[20];
-	__le32 cid;
-	__le32 flags;
-	__le32 ref_count;
-} __packed;
-
-#define SMD_CHANNEL_FLAGS_EDGE_MASK	0xff
-#define SMD_CHANNEL_FLAGS_STREAM	BIT(8)
-#define SMD_CHANNEL_FLAGS_PACKET	BIT(9)
-
-/*
- * Each smd packet contains a 20 byte header, with the first 4 being the length
- * of the packet.
- */
-#define SMD_PACKET_HEADER_LEN	20
-
-/*
- * Signal the remote processor associated with 'channel'.
- */
-static void qcom_smd_signal_channel(struct qcom_smd_channel *channel)
-{
-	struct qcom_smd_edge *edge = channel->edge;
-
-	regmap_write(edge->ipc_regmap, edge->ipc_offset, BIT(edge->ipc_bit));
-}
-
-/*
- * Initialize the tx channel info
- */
-static void qcom_smd_channel_reset(struct qcom_smd_channel *channel)
-{
-	SET_TX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED);
-	SET_TX_CHANNEL_FLAG(channel, fDSR, 0);
-	SET_TX_CHANNEL_FLAG(channel, fCTS, 0);
-	SET_TX_CHANNEL_FLAG(channel, fCD, 0);
-	SET_TX_CHANNEL_FLAG(channel, fRI, 0);
-	SET_TX_CHANNEL_FLAG(channel, fHEAD, 0);
-	SET_TX_CHANNEL_FLAG(channel, fTAIL, 0);
-	SET_TX_CHANNEL_FLAG(channel, fSTATE, 1);
-	SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 1);
-	SET_TX_CHANNEL_INFO(channel, head, 0);
-	SET_RX_CHANNEL_INFO(channel, tail, 0);
-
-	qcom_smd_signal_channel(channel);
-
-	channel->state = SMD_CHANNEL_CLOSED;
-	channel->pkt_size = 0;
-}
-
-/*
- * Set the callback for a channel, with appropriate locking
- */
-static void qcom_smd_channel_set_callback(struct qcom_smd_channel *channel,
-					  qcom_smd_cb_t cb)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&channel->recv_lock, flags);
-	channel->cb = cb;
-	spin_unlock_irqrestore(&channel->recv_lock, flags);
-};
-
-/*
- * Calculate the amount of data available in the rx fifo
- */
-static size_t qcom_smd_channel_get_rx_avail(struct qcom_smd_channel *channel)
-{
-	unsigned head;
-	unsigned tail;
-
-	head = GET_RX_CHANNEL_INFO(channel, head);
-	tail = GET_RX_CHANNEL_INFO(channel, tail);
-
-	return (head - tail) & (channel->fifo_size - 1);
-}
-
-/*
- * Set tx channel state and inform the remote processor
- */
-static void qcom_smd_channel_set_state(struct qcom_smd_channel *channel,
-				       int state)
-{
-	struct qcom_smd_edge *edge = channel->edge;
-	bool is_open = state == SMD_CHANNEL_OPENED;
-
-	if (channel->state == state)
-		return;
-
-	dev_dbg(&edge->dev, "set_state(%s, %d)\n", channel->name, state);
-
-	SET_TX_CHANNEL_FLAG(channel, fDSR, is_open);
-	SET_TX_CHANNEL_FLAG(channel, fCTS, is_open);
-	SET_TX_CHANNEL_FLAG(channel, fCD, is_open);
-
-	SET_TX_CHANNEL_INFO(channel, state, state);
-	SET_TX_CHANNEL_FLAG(channel, fSTATE, 1);
-
-	channel->state = state;
-	qcom_smd_signal_channel(channel);
-}
-
-/*
- * Copy count bytes of data using 32bit accesses, if that's required.
- */
-static void smd_copy_to_fifo(void __iomem *dst,
-			     const void *src,
-			     size_t count,
-			     bool word_aligned)
-{
-	if (word_aligned) {
-		__iowrite32_copy(dst, src, count / sizeof(u32));
-	} else {
-		memcpy_toio(dst, src, count);
-	}
-}
-
-/*
- * Copy count bytes of data using 32bit accesses, if that is required.
- */
-static void smd_copy_from_fifo(void *dst,
-			       const void __iomem *src,
-			       size_t count,
-			       bool word_aligned)
-{
-	if (word_aligned) {
-		__ioread32_copy(dst, src, count / sizeof(u32));
-	} else {
-		memcpy_fromio(dst, src, count);
-	}
-}
-
-/*
- * Read count bytes of data from the rx fifo into buf, but don't advance the
- * tail.
- */
-static size_t qcom_smd_channel_peek(struct qcom_smd_channel *channel,
-				    void *buf, size_t count)
-{
-	bool word_aligned;
-	unsigned tail;
-	size_t len;
-
-	word_aligned = channel->info_word;
-	tail = GET_RX_CHANNEL_INFO(channel, tail);
-
-	len = min_t(size_t, count, channel->fifo_size - tail);
-	if (len) {
-		smd_copy_from_fifo(buf,
-				   channel->rx_fifo + tail,
-				   len,
-				   word_aligned);
-	}
-
-	if (len != count) {
-		smd_copy_from_fifo(buf + len,
-				   channel->rx_fifo,
-				   count - len,
-				   word_aligned);
-	}
-
-	return count;
-}
-
-/*
- * Advance the rx tail by count bytes.
- */
-static void qcom_smd_channel_advance(struct qcom_smd_channel *channel,
-				     size_t count)
-{
-	unsigned tail;
-
-	tail = GET_RX_CHANNEL_INFO(channel, tail);
-	tail += count;
-	tail &= (channel->fifo_size - 1);
-	SET_RX_CHANNEL_INFO(channel, tail, tail);
-}
-
-/*
- * Read out a single packet from the rx fifo and deliver it to the device
- */
-static int qcom_smd_channel_recv_single(struct qcom_smd_channel *channel)
-{
-	unsigned tail;
-	size_t len;
-	void *ptr;
-	int ret;
-
-	if (!channel->cb)
-		return 0;
-
-	tail = GET_RX_CHANNEL_INFO(channel, tail);
-
-	/* Use bounce buffer if the data wraps */
-	if (tail + channel->pkt_size >= channel->fifo_size) {
-		ptr = channel->bounce_buffer;
-		len = qcom_smd_channel_peek(channel, ptr, channel->pkt_size);
-	} else {
-		ptr = channel->rx_fifo + tail;
-		len = channel->pkt_size;
-	}
-
-	ret = channel->cb(channel, ptr, len);
-	if (ret < 0)
-		return ret;
-
-	/* Only forward the tail if the client consumed the data */
-	qcom_smd_channel_advance(channel, len);
-
-	channel->pkt_size = 0;
-
-	return 0;
-}
-
-/*
- * Per channel interrupt handling
- */
-static bool qcom_smd_channel_intr(struct qcom_smd_channel *channel)
-{
-	bool need_state_scan = false;
-	int remote_state;
-	__le32 pktlen;
-	int avail;
-	int ret;
-
-	/* Handle state changes */
-	remote_state = GET_RX_CHANNEL_INFO(channel, state);
-	if (remote_state != channel->remote_state) {
-		channel->remote_state = remote_state;
-		need_state_scan = true;
-	}
-	/* Indicate that we have seen any state change */
-	SET_RX_CHANNEL_FLAG(channel, fSTATE, 0);
-
-	/* Signal waiting qcom_smd_send() about the interrupt */
-	if (!GET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR))
-		wake_up_interruptible(&channel->fblockread_event);
-
-	/* Don't consume any data until we've opened the channel */
-	if (channel->state != SMD_CHANNEL_OPENED)
-		goto out;
-
-	/* Indicate that we've seen the new data */
-	SET_RX_CHANNEL_FLAG(channel, fHEAD, 0);
-
-	/* Consume data */
-	for (;;) {
-		avail = qcom_smd_channel_get_rx_avail(channel);
-
-		if (!channel->pkt_size && avail >= SMD_PACKET_HEADER_LEN) {
-			qcom_smd_channel_peek(channel, &pktlen, sizeof(pktlen));
-			qcom_smd_channel_advance(channel, SMD_PACKET_HEADER_LEN);
-			channel->pkt_size = le32_to_cpu(pktlen);
-		} else if (channel->pkt_size && avail >= channel->pkt_size) {
-			ret = qcom_smd_channel_recv_single(channel);
-			if (ret)
-				break;
-		} else {
-			break;
-		}
-	}
-
-	/* Indicate that we have seen and updated tail */
-	SET_RX_CHANNEL_FLAG(channel, fTAIL, 1);
-
-	/* Signal the remote that we've consumed the data (if requested) */
-	if (!GET_RX_CHANNEL_FLAG(channel, fBLOCKREADINTR)) {
-		/* Ensure ordering of channel info updates */
-		wmb();
-
-		qcom_smd_signal_channel(channel);
-	}
-
-out:
-	return need_state_scan;
-}
-
-/*
- * The edge interrupts are triggered by the remote processor on state changes,
- * channel info updates or when new channels are created.
- */
-static irqreturn_t qcom_smd_edge_intr(int irq, void *data)
-{
-	struct qcom_smd_edge *edge = data;
-	struct qcom_smd_channel *channel;
-	unsigned available;
-	bool kick_scanner = false;
-	bool kick_state = false;
-
-	/*
-	 * Handle state changes or data on each of the channels on this edge
-	 */
-	spin_lock(&edge->channels_lock);
-	list_for_each_entry(channel, &edge->channels, list) {
-		spin_lock(&channel->recv_lock);
-		kick_state |= qcom_smd_channel_intr(channel);
-		spin_unlock(&channel->recv_lock);
-	}
-	spin_unlock(&edge->channels_lock);
-
-	/*
-	 * Creating a new channel requires allocating an smem entry, so we only
-	 * have to scan if the amount of available space in smem have changed
-	 * since last scan.
-	 */
-	available = qcom_smem_get_free_space(edge->remote_pid);
-	if (available != edge->smem_available) {
-		edge->smem_available = available;
-		kick_scanner = true;
-	}
-
-	if (kick_scanner)
-		schedule_work(&edge->scan_work);
-	if (kick_state)
-		schedule_work(&edge->state_work);
-
-	return IRQ_HANDLED;
-}
-
-/*
- * Delivers any outstanding packets in the rx fifo, can be used after probe of
- * the clients to deliver any packets that wasn't delivered before the client
- * was setup.
- */
-static void qcom_smd_channel_resume(struct qcom_smd_channel *channel)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&channel->recv_lock, flags);
-	qcom_smd_channel_intr(channel);
-	spin_unlock_irqrestore(&channel->recv_lock, flags);
-}
-
-/*
- * Calculate how much space is available in the tx fifo.
- */
-static size_t qcom_smd_get_tx_avail(struct qcom_smd_channel *channel)
-{
-	unsigned head;
-	unsigned tail;
-	unsigned mask = channel->fifo_size - 1;
-
-	head = GET_TX_CHANNEL_INFO(channel, head);
-	tail = GET_TX_CHANNEL_INFO(channel, tail);
-
-	return mask - ((head - tail) & mask);
-}
-
-/*
- * Write count bytes of data into channel, possibly wrapping in the ring buffer
- */
-static int qcom_smd_write_fifo(struct qcom_smd_channel *channel,
-			       const void *data,
-			       size_t count)
-{
-	bool word_aligned;
-	unsigned head;
-	size_t len;
-
-	word_aligned = channel->info_word;
-	head = GET_TX_CHANNEL_INFO(channel, head);
-
-	len = min_t(size_t, count, channel->fifo_size - head);
-	if (len) {
-		smd_copy_to_fifo(channel->tx_fifo + head,
-				 data,
-				 len,
-				 word_aligned);
-	}
-
-	if (len != count) {
-		smd_copy_to_fifo(channel->tx_fifo,
-				 data + len,
-				 count - len,
-				 word_aligned);
-	}
-
-	head += count;
-	head &= (channel->fifo_size - 1);
-	SET_TX_CHANNEL_INFO(channel, head, head);
-
-	return count;
-}
-
-/**
- * qcom_smd_send - write data to smd channel
- * @channel:	channel handle
- * @data:	buffer of data to write
- * @len:	number of bytes to write
- *
- * This is a blocking write of len bytes into the channel's tx ring buffer and
- * signal the remote end. It will sleep until there is enough space available
- * in the tx buffer, utilizing the fBLOCKREADINTR signaling mechanism to avoid
- * polling.
- */
-int qcom_smd_send(struct qcom_smd_channel *channel, const void *data, int len)
-{
-	__le32 hdr[5] = { cpu_to_le32(len), };
-	int tlen = sizeof(hdr) + len;
-	int ret;
-
-	/* Word aligned channels only accept word size aligned data */
-	if (channel->info_word && len % 4)
-		return -EINVAL;
-
-	/* Reject packets that are too big */
-	if (tlen >= channel->fifo_size)
-		return -EINVAL;
-
-	ret = mutex_lock_interruptible(&channel->tx_lock);
-	if (ret)
-		return ret;
-
-	while (qcom_smd_get_tx_avail(channel) < tlen) {
-		if (channel->state != SMD_CHANNEL_OPENED) {
-			ret = -EPIPE;
-			goto out;
-		}
-
-		SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 0);
-
-		ret = wait_event_interruptible(channel->fblockread_event,
-				       qcom_smd_get_tx_avail(channel) >= tlen ||
-				       channel->state != SMD_CHANNEL_OPENED);
-		if (ret)
-			goto out;
-
-		SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 1);
-	}
-
-	SET_TX_CHANNEL_FLAG(channel, fTAIL, 0);
-
-	qcom_smd_write_fifo(channel, hdr, sizeof(hdr));
-	qcom_smd_write_fifo(channel, data, len);
-
-	SET_TX_CHANNEL_FLAG(channel, fHEAD, 1);
-
-	/* Ensure ordering of channel info updates */
-	wmb();
-
-	qcom_smd_signal_channel(channel);
-
-out:
-	mutex_unlock(&channel->tx_lock);
-
-	return ret;
-}
-EXPORT_SYMBOL(qcom_smd_send);
-
-static struct qcom_smd_device *to_smd_device(struct device *dev)
-{
-	return container_of(dev, struct qcom_smd_device, dev);
-}
-
-static struct qcom_smd_driver *to_smd_driver(struct device *dev)
-{
-	struct qcom_smd_device *qsdev = to_smd_device(dev);
-
-	return container_of(qsdev->dev.driver, struct qcom_smd_driver, driver);
-}
-
-static int qcom_smd_dev_match(struct device *dev, struct device_driver *drv)
-{
-	struct qcom_smd_device *qsdev = to_smd_device(dev);
-	struct qcom_smd_driver *qsdrv = container_of(drv, struct qcom_smd_driver, driver);
-	const struct qcom_smd_id *match = qsdrv->smd_match_table;
-	const char *name = qsdev->channel->name;
-
-	if (match) {
-		while (match->name[0]) {
-			if (!strcmp(match->name, name))
-				return 1;
-			match++;
-		}
-	}
-
-	return of_driver_match_device(dev, drv);
-}
-
-/*
- * Helper for opening a channel
- */
-static int qcom_smd_channel_open(struct qcom_smd_channel *channel,
-				 qcom_smd_cb_t cb)
-{
-	size_t bb_size;
-
-	/*
-	 * Packets are maximum 4k, but reduce if the fifo is smaller
-	 */
-	bb_size = min(channel->fifo_size, SZ_4K);
-	channel->bounce_buffer = kmalloc(bb_size, GFP_KERNEL);
-	if (!channel->bounce_buffer)
-		return -ENOMEM;
-
-	qcom_smd_channel_set_callback(channel, cb);
-	qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENING);
-	qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENED);
-
-	return 0;
-}
-
-/*
- * Helper for closing and resetting a channel
- */
-static void qcom_smd_channel_close(struct qcom_smd_channel *channel)
-{
-	qcom_smd_channel_set_callback(channel, NULL);
-
-	kfree(channel->bounce_buffer);
-	channel->bounce_buffer = NULL;
-
-	qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSED);
-	qcom_smd_channel_reset(channel);
-}
-
-/*
- * Probe the smd client.
- *
- * The remote side have indicated that it want the channel to be opened, so
- * complete the state handshake and probe our client driver.
- */
-static int qcom_smd_dev_probe(struct device *dev)
-{
-	struct qcom_smd_device *qsdev = to_smd_device(dev);
-	struct qcom_smd_driver *qsdrv = to_smd_driver(dev);
-	struct qcom_smd_channel *channel = qsdev->channel;
-	int ret;
-
-	ret = qcom_smd_channel_open(channel, qsdrv->callback);
-	if (ret)
-		return ret;
-
-	ret = qsdrv->probe(qsdev);
-	if (ret)
-		goto err;
-
-	qcom_smd_channel_resume(channel);
-
-	return 0;
-
-err:
-	dev_err(&qsdev->dev, "probe failed\n");
-
-	qcom_smd_channel_close(channel);
-	return ret;
-}
-
-/*
- * Remove the smd client.
- *
- * The channel is going away, for some reason, so remove the smd client and
- * reset the channel state.
- */
-static int qcom_smd_dev_remove(struct device *dev)
-{
-	struct qcom_smd_device *qsdev = to_smd_device(dev);
-	struct qcom_smd_driver *qsdrv = to_smd_driver(dev);
-	struct qcom_smd_channel *channel = qsdev->channel;
-
-	qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSING);
-
-	/*
-	 * Make sure we don't race with the code receiving data.
-	 */
-	qcom_smd_channel_set_callback(channel, NULL);
-
-	/* Wake up any sleepers in qcom_smd_send() */
-	wake_up_interruptible(&channel->fblockread_event);
-
-	/*
-	 * We expect that the client might block in remove() waiting for any
-	 * outstanding calls to qcom_smd_send() to wake up and finish.
-	 */
-	if (qsdrv->remove)
-		qsdrv->remove(qsdev);
-
-	/* The client is now gone, close the primary channel */
-	qcom_smd_channel_close(channel);
-	channel->qsdev = NULL;
-
-	return 0;
-}
-
-static struct bus_type qcom_smd_bus = {
-	.name = "qcom_smd",
-	.match = qcom_smd_dev_match,
-	.probe = qcom_smd_dev_probe,
-	.remove = qcom_smd_dev_remove,
-};
-
-/*
- * Release function for the qcom_smd_device object.
- */
-static void qcom_smd_release_device(struct device *dev)
-{
-	struct qcom_smd_device *qsdev = to_smd_device(dev);
-
-	kfree(qsdev);
-}
-
-/*
- * Finds the device_node for the smd child interested in this channel.
- */
-static struct device_node *qcom_smd_match_channel(struct device_node *edge_node,
-						  const char *channel)
-{
-	struct device_node *child;
-	const char *name;
-	const char *key;
-	int ret;
-
-	for_each_available_child_of_node(edge_node, child) {
-		key = "qcom,smd-channels";
-		ret = of_property_read_string(child, key, &name);
-		if (ret)
-			continue;
-
-		if (strcmp(name, channel) == 0)
-			return child;
-	}
-
-	return NULL;
-}
-
-/*
- * Create a smd client device for channel that is being opened.
- */
-static int qcom_smd_create_device(struct qcom_smd_channel *channel)
-{
-	struct qcom_smd_device *qsdev;
-	struct qcom_smd_edge *edge = channel->edge;
-	struct device_node *node;
-	int ret;
-
-	if (channel->qsdev)
-		return -EEXIST;
-
-	dev_dbg(&edge->dev, "registering '%s'\n", channel->name);
-
-	qsdev = kzalloc(sizeof(*qsdev), GFP_KERNEL);
-	if (!qsdev)
-		return -ENOMEM;
-
-	node = qcom_smd_match_channel(edge->of_node, channel->name);
-	dev_set_name(&qsdev->dev, "%s.%s",
-		     edge->of_node->name,
-		     node ? node->name : channel->name);
-
-	qsdev->dev.parent = &edge->dev;
-	qsdev->dev.bus = &qcom_smd_bus;
-	qsdev->dev.release = qcom_smd_release_device;
-	qsdev->dev.of_node = node;
-
-	qsdev->channel = channel;
-
-	channel->qsdev = qsdev;
-
-	ret = device_register(&qsdev->dev);
-	if (ret) {
-		dev_err(&edge->dev, "device_register failed: %d\n", ret);
-		put_device(&qsdev->dev);
-	}
-
-	return ret;
-}
-
-/*
- * Destroy a smd client device for a channel that's going away.
- */
-static void qcom_smd_destroy_device(struct qcom_smd_channel *channel)
-{
-	struct device *dev;
-
-	BUG_ON(!channel->qsdev);
-
-	dev = &channel->qsdev->dev;
-
-	device_unregister(dev);
-	of_node_put(dev->of_node);
-	put_device(dev);
-}
-
-/**
- * qcom_smd_driver_register - register a smd driver
- * @qsdrv:	qcom_smd_driver struct
- */
-int qcom_smd_driver_register(struct qcom_smd_driver *qsdrv)
-{
-	qsdrv->driver.bus = &qcom_smd_bus;
-	return driver_register(&qsdrv->driver);
-}
-EXPORT_SYMBOL(qcom_smd_driver_register);
-
-void *qcom_smd_get_drvdata(struct qcom_smd_channel *channel)
-{
-	return channel->drvdata;
-}
-EXPORT_SYMBOL(qcom_smd_get_drvdata);
-
-void qcom_smd_set_drvdata(struct qcom_smd_channel *channel, void *data)
-{
-	channel->drvdata = data;
-}
-EXPORT_SYMBOL(qcom_smd_set_drvdata);
-
-/**
- * qcom_smd_driver_unregister - unregister a smd driver
- * @qsdrv:	qcom_smd_driver struct
- */
-void qcom_smd_driver_unregister(struct qcom_smd_driver *qsdrv)
-{
-	driver_unregister(&qsdrv->driver);
-}
-EXPORT_SYMBOL(qcom_smd_driver_unregister);
-
-static struct qcom_smd_channel *
-qcom_smd_find_channel(struct qcom_smd_edge *edge, const char *name)
-{
-	struct qcom_smd_channel *channel;
-	struct qcom_smd_channel *ret = NULL;
-	unsigned long flags;
-	unsigned state;
-
-	spin_lock_irqsave(&edge->channels_lock, flags);
-	list_for_each_entry(channel, &edge->channels, list) {
-		if (strcmp(channel->name, name))
-			continue;
-
-		state = GET_RX_CHANNEL_INFO(channel, state);
-		if (state != SMD_CHANNEL_OPENING &&
-		    state != SMD_CHANNEL_OPENED)
-			continue;
-
-		ret = channel;
-		break;
-	}
-	spin_unlock_irqrestore(&edge->channels_lock, flags);
-
-	return ret;
-}
-
-/**
- * qcom_smd_open_channel() - claim additional channels on the same edge
- * @sdev:	smd_device handle
- * @name:	channel name
- * @cb:		callback method to use for incoming data
- *
- * Returns a channel handle on success, or -EPROBE_DEFER if the channel isn't
- * ready.
- *
- * Any channels returned must be closed with a call to qcom_smd_close_channel()
- */
-struct qcom_smd_channel *qcom_smd_open_channel(struct qcom_smd_channel *parent,
-					       const char *name,
-					       qcom_smd_cb_t cb)
-{
-	struct qcom_smd_channel *channel;
-	struct qcom_smd_device *sdev = parent->qsdev;
-	struct qcom_smd_edge *edge = parent->edge;
-	int ret;
-
-	/* Wait up to HZ for the channel to appear */
-	ret = wait_event_interruptible_timeout(edge->new_channel_event,
-			(channel = qcom_smd_find_channel(edge, name)) != NULL,
-			HZ);
-	if (!ret)
-		return ERR_PTR(-ETIMEDOUT);
-
-	if (channel->state != SMD_CHANNEL_CLOSED) {
-		dev_err(&sdev->dev, "channel %s is busy\n", channel->name);
-		return ERR_PTR(-EBUSY);
-	}
-
-	channel->qsdev = sdev;
-	ret = qcom_smd_channel_open(channel, cb);
-	if (ret) {
-		channel->qsdev = NULL;
-		return ERR_PTR(ret);
-	}
-
-	return channel;
-}
-EXPORT_SYMBOL(qcom_smd_open_channel);
-
-/**
- * qcom_smd_close_channel() - close an additionally opened channel
- * @channel:	channel handle, returned by qcom_smd_open_channel()
- */
-void qcom_smd_close_channel(struct qcom_smd_channel *channel)
-{
-	qcom_smd_channel_close(channel);
-	channel->qsdev = NULL;
-}
-EXPORT_SYMBOL(qcom_smd_close_channel);
-
-/*
- * Allocate the qcom_smd_channel object for a newly found smd channel,
- * retrieving and validating the smem items involved.
- */
-static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *edge,
-							unsigned smem_info_item,
-							unsigned smem_fifo_item,
-							char *name)
-{
-	struct qcom_smd_channel *channel;
-	size_t fifo_size;
-	size_t info_size;
-	void *fifo_base;
-	void *info;
-	int ret;
-
-	channel = devm_kzalloc(&edge->dev, sizeof(*channel), GFP_KERNEL);
-	if (!channel)
-		return ERR_PTR(-ENOMEM);
-
-	channel->edge = edge;
-	channel->name = devm_kstrdup(&edge->dev, name, GFP_KERNEL);
-	if (!channel->name)
-		return ERR_PTR(-ENOMEM);
-
-	mutex_init(&channel->tx_lock);
-	spin_lock_init(&channel->recv_lock);
-	init_waitqueue_head(&channel->fblockread_event);
-
-	info = qcom_smem_get(edge->remote_pid, smem_info_item, &info_size);
-	if (IS_ERR(info)) {
-		ret = PTR_ERR(info);
-		goto free_name_and_channel;
-	}
-
-	/*
-	 * Use the size of the item to figure out which channel info struct to
-	 * use.
-	 */
-	if (info_size == 2 * sizeof(struct smd_channel_info_word)) {
-		channel->info_word = info;
-	} else if (info_size == 2 * sizeof(struct smd_channel_info)) {
-		channel->info = info;
-	} else {
-		dev_err(&edge->dev,
-			"channel info of size %zu not supported\n", info_size);
-		ret = -EINVAL;
-		goto free_name_and_channel;
-	}
-
-	fifo_base = qcom_smem_get(edge->remote_pid, smem_fifo_item, &fifo_size);
-	if (IS_ERR(fifo_base)) {
-		ret =  PTR_ERR(fifo_base);
-		goto free_name_and_channel;
-	}
-
-	/* The channel consist of a rx and tx fifo of equal size */
-	fifo_size /= 2;
-
-	dev_dbg(&edge->dev, "new channel '%s' info-size: %zu fifo-size: %zu\n",
-			  name, info_size, fifo_size);
-
-	channel->tx_fifo = fifo_base;
-	channel->rx_fifo = fifo_base + fifo_size;
-	channel->fifo_size = fifo_size;
-
-	qcom_smd_channel_reset(channel);
-
-	return channel;
-
-free_name_and_channel:
-	devm_kfree(&edge->dev, channel->name);
-	devm_kfree(&edge->dev, channel);
-
-	return ERR_PTR(ret);
-}
-
-/*
- * Scans the allocation table for any newly allocated channels, calls
- * qcom_smd_create_channel() to create representations of these and add
- * them to the edge's list of channels.
- */
-static void qcom_channel_scan_worker(struct work_struct *work)
-{
-	struct qcom_smd_edge *edge = container_of(work, struct qcom_smd_edge, scan_work);
-	struct qcom_smd_alloc_entry *alloc_tbl;
-	struct qcom_smd_alloc_entry *entry;
-	struct qcom_smd_channel *channel;
-	unsigned long flags;
-	unsigned fifo_id;
-	unsigned info_id;
-	int tbl;
-	int i;
-	u32 eflags, cid;
-
-	for (tbl = 0; tbl < SMD_ALLOC_TBL_COUNT; tbl++) {
-		alloc_tbl = qcom_smem_get(edge->remote_pid,
-				    smem_items[tbl].alloc_tbl_id, NULL);
-		if (IS_ERR(alloc_tbl))
-			continue;
-
-		for (i = 0; i < SMD_ALLOC_TBL_SIZE; i++) {
-			entry = &alloc_tbl[i];
-			eflags = le32_to_cpu(entry->flags);
-			if (test_bit(i, edge->allocated[tbl]))
-				continue;
-
-			if (entry->ref_count == 0)
-				continue;
-
-			if (!entry->name[0])
-				continue;
-
-			if (!(eflags & SMD_CHANNEL_FLAGS_PACKET))
-				continue;
-
-			if ((eflags & SMD_CHANNEL_FLAGS_EDGE_MASK) != edge->edge_id)
-				continue;
-
-			cid = le32_to_cpu(entry->cid);
-			info_id = smem_items[tbl].info_base_id + cid;
-			fifo_id = smem_items[tbl].fifo_base_id + cid;
-
-			channel = qcom_smd_create_channel(edge, info_id, fifo_id, entry->name);
-			if (IS_ERR(channel))
-				continue;
-
-			spin_lock_irqsave(&edge->channels_lock, flags);
-			list_add(&channel->list, &edge->channels);
-			spin_unlock_irqrestore(&edge->channels_lock, flags);
-
-			dev_dbg(&edge->dev, "new channel found: '%s'\n", channel->name);
-			set_bit(i, edge->allocated[tbl]);
-
-			wake_up_interruptible(&edge->new_channel_event);
-		}
-	}
-
-	schedule_work(&edge->state_work);
-}
-
-/*
- * This per edge worker scans smem for any new channels and register these. It
- * then scans all registered channels for state changes that should be handled
- * by creating or destroying smd client devices for the registered channels.
- *
- * LOCKING: edge->channels_lock only needs to cover the list operations, as the
- * worker is killed before any channels are deallocated
- */
-static void qcom_channel_state_worker(struct work_struct *work)
-{
-	struct qcom_smd_channel *channel;
-	struct qcom_smd_edge *edge = container_of(work,
-						  struct qcom_smd_edge,
-						  state_work);
-	unsigned remote_state;
-	unsigned long flags;
-
-	/*
-	 * Register a device for any closed channel where the remote processor
-	 * is showing interest in opening the channel.
-	 */
-	spin_lock_irqsave(&edge->channels_lock, flags);
-	list_for_each_entry(channel, &edge->channels, list) {
-		if (channel->state != SMD_CHANNEL_CLOSED)
-			continue;
-
-		remote_state = GET_RX_CHANNEL_INFO(channel, state);
-		if (remote_state != SMD_CHANNEL_OPENING &&
-		    remote_state != SMD_CHANNEL_OPENED)
-			continue;
-
-		spin_unlock_irqrestore(&edge->channels_lock, flags);
-		qcom_smd_create_device(channel);
-		spin_lock_irqsave(&edge->channels_lock, flags);
-	}
-
-	/*
-	 * Unregister the device for any channel that is opened where the
-	 * remote processor is closing the channel.
-	 */
-	list_for_each_entry(channel, &edge->channels, list) {
-		if (channel->state != SMD_CHANNEL_OPENING &&
-		    channel->state != SMD_CHANNEL_OPENED)
-			continue;
-
-		remote_state = GET_RX_CHANNEL_INFO(channel, state);
-		if (remote_state == SMD_CHANNEL_OPENING ||
-		    remote_state == SMD_CHANNEL_OPENED)
-			continue;
-
-		spin_unlock_irqrestore(&edge->channels_lock, flags);
-		qcom_smd_destroy_device(channel);
-		spin_lock_irqsave(&edge->channels_lock, flags);
-	}
-	spin_unlock_irqrestore(&edge->channels_lock, flags);
-}
-
-/*
- * Parses an of_node describing an edge.
- */
-static int qcom_smd_parse_edge(struct device *dev,
-			       struct device_node *node,
-			       struct qcom_smd_edge *edge)
-{
-	struct device_node *syscon_np;
-	const char *key;
-	int irq;
-	int ret;
-
-	INIT_LIST_HEAD(&edge->channels);
-	spin_lock_init(&edge->channels_lock);
-
-	INIT_WORK(&edge->scan_work, qcom_channel_scan_worker);
-	INIT_WORK(&edge->state_work, qcom_channel_state_worker);
-
-	edge->of_node = of_node_get(node);
-
-	key = "qcom,smd-edge";
-	ret = of_property_read_u32(node, key, &edge->edge_id);
-	if (ret) {
-		dev_err(dev, "edge missing %s property\n", key);
-		return -EINVAL;
-	}
-
-	edge->remote_pid = QCOM_SMEM_HOST_ANY;
-	key = "qcom,remote-pid";
-	of_property_read_u32(node, key, &edge->remote_pid);
-
-	syscon_np = of_parse_phandle(node, "qcom,ipc", 0);
-	if (!syscon_np) {
-		dev_err(dev, "no qcom,ipc node\n");
-		return -ENODEV;
-	}
-
-	edge->ipc_regmap = syscon_node_to_regmap(syscon_np);
-	if (IS_ERR(edge->ipc_regmap))
-		return PTR_ERR(edge->ipc_regmap);
-
-	key = "qcom,ipc";
-	ret = of_property_read_u32_index(node, key, 1, &edge->ipc_offset);
-	if (ret < 0) {
-		dev_err(dev, "no offset in %s\n", key);
-		return -EINVAL;
-	}
-
-	ret = of_property_read_u32_index(node, key, 2, &edge->ipc_bit);
-	if (ret < 0) {
-		dev_err(dev, "no bit in %s\n", key);
-		return -EINVAL;
-	}
-
-	irq = irq_of_parse_and_map(node, 0);
-	if (irq < 0) {
-		dev_err(dev, "required smd interrupt missing\n");
-		return -EINVAL;
-	}
-
-	ret = devm_request_irq(dev, irq,
-			       qcom_smd_edge_intr, IRQF_TRIGGER_RISING,
-			       node->name, edge);
-	if (ret) {
-		dev_err(dev, "failed to request smd irq\n");
-		return ret;
-	}
-
-	edge->irq = irq;
-
-	return 0;
-}
-
-/*
- * Release function for an edge.
- * Reset the state of each associated channel and free the edge context.
- */
-static void qcom_smd_edge_release(struct device *dev)
-{
-	struct qcom_smd_channel *channel;
-	struct qcom_smd_edge *edge = to_smd_edge(dev);
-
-	list_for_each_entry(channel, &edge->channels, list) {
-		SET_RX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED);
-		SET_RX_CHANNEL_INFO(channel, head, 0);
-		SET_RX_CHANNEL_INFO(channel, tail, 0);
-	}
-
-	kfree(edge);
-}
-
-/**
- * qcom_smd_register_edge() - register an edge based on an device_node
- * @parent:	parent device for the edge
- * @node:	device_node describing the edge
- *
- * Returns an edge reference, or negative ERR_PTR() on failure.
- */
-struct qcom_smd_edge *qcom_smd_register_edge(struct device *parent,
-					     struct device_node *node)
-{
-	struct qcom_smd_edge *edge;
-	int ret;
-
-	edge = kzalloc(sizeof(*edge), GFP_KERNEL);
-	if (!edge)
-		return ERR_PTR(-ENOMEM);
-
-	init_waitqueue_head(&edge->new_channel_event);
-
-	edge->dev.parent = parent;
-	edge->dev.release = qcom_smd_edge_release;
-	dev_set_name(&edge->dev, "%s:%s", dev_name(parent), node->name);
-	ret = device_register(&edge->dev);
-	if (ret) {
-		pr_err("failed to register smd edge\n");
-		return ERR_PTR(ret);
-	}
-
-	ret = qcom_smd_parse_edge(&edge->dev, node, edge);
-	if (ret) {
-		dev_err(&edge->dev, "failed to parse smd edge\n");
-		goto unregister_dev;
-	}
-
-	schedule_work(&edge->scan_work);
-
-	return edge;
-
-unregister_dev:
-	put_device(&edge->dev);
-	return ERR_PTR(ret);
-}
-EXPORT_SYMBOL(qcom_smd_register_edge);
-
-static int qcom_smd_remove_device(struct device *dev, void *data)
-{
-	device_unregister(dev);
-	of_node_put(dev->of_node);
-	put_device(dev);
-
-	return 0;
-}
-
-/**
- * qcom_smd_unregister_edge() - release an edge and its children
- * @edge:	edge reference acquired from qcom_smd_register_edge
- */
-int qcom_smd_unregister_edge(struct qcom_smd_edge *edge)
-{
-	int ret;
-
-	disable_irq(edge->irq);
-	cancel_work_sync(&edge->scan_work);
-	cancel_work_sync(&edge->state_work);
-
-	ret = device_for_each_child(&edge->dev, NULL, qcom_smd_remove_device);
-	if (ret)
-		dev_warn(&edge->dev, "can't remove smd device: %d\n", ret);
-
-	device_unregister(&edge->dev);
-
-	return 0;
-}
-EXPORT_SYMBOL(qcom_smd_unregister_edge);
-
-static int qcom_smd_probe(struct platform_device *pdev)
-{
-	struct device_node *node;
-	void *p;
-
-	/* Wait for smem */
-	p = qcom_smem_get(QCOM_SMEM_HOST_ANY, smem_items[0].alloc_tbl_id, NULL);
-	if (PTR_ERR(p) == -EPROBE_DEFER)
-		return PTR_ERR(p);
-
-	for_each_available_child_of_node(pdev->dev.of_node, node)
-		qcom_smd_register_edge(&pdev->dev, node);
-
-	return 0;
-}
-
-static int qcom_smd_remove_edge(struct device *dev, void *data)
-{
-	struct qcom_smd_edge *edge = to_smd_edge(dev);
-
-	return qcom_smd_unregister_edge(edge);
-}
-
-/*
- * Shut down all smd clients by making sure that each edge stops processing
- * events and scanning for new channels, then call destroy on the devices.
- */
-static int qcom_smd_remove(struct platform_device *pdev)
-{
-	int ret;
-
-	ret = device_for_each_child(&pdev->dev, NULL, qcom_smd_remove_edge);
-	if (ret)
-		dev_warn(&pdev->dev, "can't remove smd device: %d\n", ret);
-
-	return ret;
-}
-
-static const struct of_device_id qcom_smd_of_match[] = {
-	{ .compatible = "qcom,smd" },
-	{}
-};
-MODULE_DEVICE_TABLE(of, qcom_smd_of_match);
-
-static struct platform_driver qcom_smd_driver = {
-	.probe = qcom_smd_probe,
-	.remove = qcom_smd_remove,
-	.driver = {
-		.name = "qcom-smd",
-		.of_match_table = qcom_smd_of_match,
-	},
-};
-
-static int __init qcom_smd_init(void)
-{
-	int ret;
-
-	ret = bus_register(&qcom_smd_bus);
-	if (ret) {
-		pr_err("failed to register smd bus: %d\n", ret);
-		return ret;
-	}
-
-	return platform_driver_register(&qcom_smd_driver);
-}
-postcore_initcall(qcom_smd_init);
-
-static void __exit qcom_smd_exit(void)
-{
-	platform_driver_unregister(&qcom_smd_driver);
-	bus_unregister(&qcom_smd_bus);
-}
-module_exit(qcom_smd_exit);
-
-MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>");
-MODULE_DESCRIPTION("Qualcomm Shared Memory Driver");
-MODULE_LICENSE("GPL v2");