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-rw-r--r--drivers/hsi/Kconfig19
-rw-r--r--drivers/hsi/Makefile6
-rw-r--r--drivers/hsi/clients/Kconfig13
-rw-r--r--drivers/hsi/clients/Makefile5
-rw-r--r--drivers/hsi/clients/hsi_char.c802
-rw-r--r--drivers/hsi/hsi.c494
-rw-r--r--drivers/hsi/hsi_boardinfo.c62
-rw-r--r--drivers/hsi/hsi_core.h35
8 files changed, 1436 insertions, 0 deletions
diff --git a/drivers/hsi/Kconfig b/drivers/hsi/Kconfig
new file mode 100644
index 000000000000..d94e38dd80c7
--- /dev/null
+++ b/drivers/hsi/Kconfig
@@ -0,0 +1,19 @@
+#
+# HSI driver configuration
+#
+menuconfig HSI
+ tristate "HSI support"
+ ---help---
+ The "High speed synchronous Serial Interface" is
+ synchronous serial interface used mainly to connect
+ application engines and cellular modems.
+
+if HSI
+
+config HSI_BOARDINFO
+ bool
+ default y
+
+source "drivers/hsi/clients/Kconfig"
+
+endif # HSI
diff --git a/drivers/hsi/Makefile b/drivers/hsi/Makefile
new file mode 100644
index 000000000000..9d5d33f90de2
--- /dev/null
+++ b/drivers/hsi/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for HSI
+#
+obj-$(CONFIG_HSI_BOARDINFO) += hsi_boardinfo.o
+obj-$(CONFIG_HSI) += hsi.o
+obj-y += clients/
diff --git a/drivers/hsi/clients/Kconfig b/drivers/hsi/clients/Kconfig
new file mode 100644
index 000000000000..3bacd275f479
--- /dev/null
+++ b/drivers/hsi/clients/Kconfig
@@ -0,0 +1,13 @@
+#
+# HSI clients configuration
+#
+
+comment "HSI clients"
+
+config HSI_CHAR
+ tristate "HSI/SSI character driver"
+ depends on HSI
+ ---help---
+ If you say Y here, you will enable the HSI/SSI character driver.
+ This driver provides a simple character device interface for
+ serial communication with the cellular modem over HSI/SSI bus.
diff --git a/drivers/hsi/clients/Makefile b/drivers/hsi/clients/Makefile
new file mode 100644
index 000000000000..327c0e27c8b0
--- /dev/null
+++ b/drivers/hsi/clients/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for HSI clients
+#
+
+obj-$(CONFIG_HSI_CHAR) += hsi_char.o
diff --git a/drivers/hsi/clients/hsi_char.c b/drivers/hsi/clients/hsi_char.c
new file mode 100644
index 000000000000..88a050df2389
--- /dev/null
+++ b/drivers/hsi/clients/hsi_char.c
@@ -0,0 +1,802 @@
+/*
+ * HSI character device driver, implements the character device
+ * interface.
+ *
+ * Copyright (C) 2010 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Andras Domokos <andras.domokos@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/atomic.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/kmemleak.h>
+#include <linux/ioctl.h>
+#include <linux/wait.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/device.h>
+#include <linux/cdev.h>
+#include <linux/uaccess.h>
+#include <linux/scatterlist.h>
+#include <linux/stat.h>
+#include <linux/hsi/hsi.h>
+#include <linux/hsi/hsi_char.h>
+
+#define HSC_DEVS 16 /* Num of channels */
+#define HSC_MSGS 4
+
+#define HSC_RXBREAK 0
+
+#define HSC_ID_BITS 6
+#define HSC_PORT_ID_BITS 4
+#define HSC_ID_MASK 3
+#define HSC_PORT_ID_MASK 3
+#define HSC_CH_MASK 0xf
+
+/*
+ * We support up to 4 controllers that can have up to 4
+ * ports, which should currently be more than enough.
+ */
+#define HSC_BASEMINOR(id, port_id) \
+ ((((id) & HSC_ID_MASK) << HSC_ID_BITS) | \
+ (((port_id) & HSC_PORT_ID_MASK) << HSC_PORT_ID_BITS))
+
+enum {
+ HSC_CH_OPEN,
+ HSC_CH_READ,
+ HSC_CH_WRITE,
+ HSC_CH_WLINE,
+};
+
+enum {
+ HSC_RX,
+ HSC_TX,
+};
+
+struct hsc_client_data;
+/**
+ * struct hsc_channel - hsi_char internal channel data
+ * @ch: channel number
+ * @flags: Keeps state of the channel (open/close, reading, writing)
+ * @free_msgs_list: List of free HSI messages/requests
+ * @rx_msgs_queue: List of pending RX requests
+ * @tx_msgs_queue: List of pending TX requests
+ * @lock: Serialize access to the lists
+ * @cl: reference to the associated hsi_client
+ * @cl_data: reference to the client data that this channels belongs to
+ * @rx_wait: RX requests wait queue
+ * @tx_wait: TX requests wait queue
+ */
+struct hsc_channel {
+ unsigned int ch;
+ unsigned long flags;
+ struct list_head free_msgs_list;
+ struct list_head rx_msgs_queue;
+ struct list_head tx_msgs_queue;
+ spinlock_t lock;
+ struct hsi_client *cl;
+ struct hsc_client_data *cl_data;
+ wait_queue_head_t rx_wait;
+ wait_queue_head_t tx_wait;
+};
+
+/**
+ * struct hsc_client_data - hsi_char internal client data
+ * @cdev: Characther device associated to the hsi_client
+ * @lock: Lock to serialize open/close access
+ * @flags: Keeps track of port state (rx hwbreak armed)
+ * @usecnt: Use count for claiming the HSI port (mutex protected)
+ * @cl: Referece to the HSI client
+ * @channels: Array of channels accessible by the client
+ */
+struct hsc_client_data {
+ struct cdev cdev;
+ struct mutex lock;
+ unsigned long flags;
+ unsigned int usecnt;
+ struct hsi_client *cl;
+ struct hsc_channel channels[HSC_DEVS];
+};
+
+/* Stores the major number dynamically allocated for hsi_char */
+static unsigned int hsc_major;
+/* Maximum buffer size that hsi_char will accept from userspace */
+static unsigned int max_data_size = 0x1000;
+module_param(max_data_size, uint, S_IRUSR | S_IWUSR);
+MODULE_PARM_DESC(max_data_size, "max read/write data size [4,8..65536] (^2)");
+
+static void hsc_add_tail(struct hsc_channel *channel, struct hsi_msg *msg,
+ struct list_head *queue)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&channel->lock, flags);
+ list_add_tail(&msg->link, queue);
+ spin_unlock_irqrestore(&channel->lock, flags);
+}
+
+static struct hsi_msg *hsc_get_first_msg(struct hsc_channel *channel,
+ struct list_head *queue)
+{
+ struct hsi_msg *msg = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&channel->lock, flags);
+
+ if (list_empty(queue))
+ goto out;
+
+ msg = list_first_entry(queue, struct hsi_msg, link);
+ list_del(&msg->link);
+out:
+ spin_unlock_irqrestore(&channel->lock, flags);
+
+ return msg;
+}
+
+static inline void hsc_msg_free(struct hsi_msg *msg)
+{
+ kfree(sg_virt(msg->sgt.sgl));
+ hsi_free_msg(msg);
+}
+
+static void hsc_free_list(struct list_head *list)
+{
+ struct hsi_msg *msg, *tmp;
+
+ list_for_each_entry_safe(msg, tmp, list, link) {
+ list_del(&msg->link);
+ hsc_msg_free(msg);
+ }
+}
+
+static void hsc_reset_list(struct hsc_channel *channel, struct list_head *l)
+{
+ unsigned long flags;
+ LIST_HEAD(list);
+
+ spin_lock_irqsave(&channel->lock, flags);
+ list_splice_init(l, &list);
+ spin_unlock_irqrestore(&channel->lock, flags);
+
+ hsc_free_list(&list);
+}
+
+static inline struct hsi_msg *hsc_msg_alloc(unsigned int alloc_size)
+{
+ struct hsi_msg *msg;
+ void *buf;
+
+ msg = hsi_alloc_msg(1, GFP_KERNEL);
+ if (!msg)
+ goto out;
+ buf = kmalloc(alloc_size, GFP_KERNEL);
+ if (!buf) {
+ hsi_free_msg(msg);
+ goto out;
+ }
+ sg_init_one(msg->sgt.sgl, buf, alloc_size);
+ /* Ignore false positive, due to sg pointer handling */
+ kmemleak_ignore(buf);
+
+ return msg;
+out:
+ return NULL;
+}
+
+static inline int hsc_msgs_alloc(struct hsc_channel *channel)
+{
+ struct hsi_msg *msg;
+ int i;
+
+ for (i = 0; i < HSC_MSGS; i++) {
+ msg = hsc_msg_alloc(max_data_size);
+ if (!msg)
+ goto out;
+ msg->channel = channel->ch;
+ list_add_tail(&msg->link, &channel->free_msgs_list);
+ }
+
+ return 0;
+out:
+ hsc_free_list(&channel->free_msgs_list);
+
+ return -ENOMEM;
+}
+
+static inline unsigned int hsc_msg_len_get(struct hsi_msg *msg)
+{
+ return msg->sgt.sgl->length;
+}
+
+static inline void hsc_msg_len_set(struct hsi_msg *msg, unsigned int len)
+{
+ msg->sgt.sgl->length = len;
+}
+
+static void hsc_rx_completed(struct hsi_msg *msg)
+{
+ struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl);
+ struct hsc_channel *channel = cl_data->channels + msg->channel;
+
+ if (test_bit(HSC_CH_READ, &channel->flags)) {
+ hsc_add_tail(channel, msg, &channel->rx_msgs_queue);
+ wake_up(&channel->rx_wait);
+ } else {
+ hsc_add_tail(channel, msg, &channel->free_msgs_list);
+ }
+}
+
+static void hsc_rx_msg_destructor(struct hsi_msg *msg)
+{
+ msg->status = HSI_STATUS_ERROR;
+ hsc_msg_len_set(msg, 0);
+ hsc_rx_completed(msg);
+}
+
+static void hsc_tx_completed(struct hsi_msg *msg)
+{
+ struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl);
+ struct hsc_channel *channel = cl_data->channels + msg->channel;
+
+ if (test_bit(HSC_CH_WRITE, &channel->flags)) {
+ hsc_add_tail(channel, msg, &channel->tx_msgs_queue);
+ wake_up(&channel->tx_wait);
+ } else {
+ hsc_add_tail(channel, msg, &channel->free_msgs_list);
+ }
+}
+
+static void hsc_tx_msg_destructor(struct hsi_msg *msg)
+{
+ msg->status = HSI_STATUS_ERROR;
+ hsc_msg_len_set(msg, 0);
+ hsc_tx_completed(msg);
+}
+
+static void hsc_break_req_destructor(struct hsi_msg *msg)
+{
+ struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl);
+
+ hsi_free_msg(msg);
+ clear_bit(HSC_RXBREAK, &cl_data->flags);
+}
+
+static void hsc_break_received(struct hsi_msg *msg)
+{
+ struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl);
+ struct hsc_channel *channel = cl_data->channels;
+ int i, ret;
+
+ /* Broadcast HWBREAK on all channels */
+ for (i = 0; i < HSC_DEVS; i++, channel++) {
+ struct hsi_msg *msg2;
+
+ if (!test_bit(HSC_CH_READ, &channel->flags))
+ continue;
+ msg2 = hsc_get_first_msg(channel, &channel->free_msgs_list);
+ if (!msg2)
+ continue;
+ clear_bit(HSC_CH_READ, &channel->flags);
+ hsc_msg_len_set(msg2, 0);
+ msg2->status = HSI_STATUS_COMPLETED;
+ hsc_add_tail(channel, msg2, &channel->rx_msgs_queue);
+ wake_up(&channel->rx_wait);
+ }
+ hsi_flush(msg->cl);
+ ret = hsi_async_read(msg->cl, msg);
+ if (ret < 0)
+ hsc_break_req_destructor(msg);
+}
+
+static int hsc_break_request(struct hsi_client *cl)
+{
+ struct hsc_client_data *cl_data = hsi_client_drvdata(cl);
+ struct hsi_msg *msg;
+ int ret;
+
+ if (test_and_set_bit(HSC_RXBREAK, &cl_data->flags))
+ return -EBUSY;
+
+ msg = hsi_alloc_msg(0, GFP_KERNEL);
+ if (!msg) {
+ clear_bit(HSC_RXBREAK, &cl_data->flags);
+ return -ENOMEM;
+ }
+ msg->break_frame = 1;
+ msg->complete = hsc_break_received;
+ msg->destructor = hsc_break_req_destructor;
+ ret = hsi_async_read(cl, msg);
+ if (ret < 0)
+ hsc_break_req_destructor(msg);
+
+ return ret;
+}
+
+static int hsc_break_send(struct hsi_client *cl)
+{
+ struct hsi_msg *msg;
+ int ret;
+
+ msg = hsi_alloc_msg(0, GFP_ATOMIC);
+ if (!msg)
+ return -ENOMEM;
+ msg->break_frame = 1;
+ msg->complete = hsi_free_msg;
+ msg->destructor = hsi_free_msg;
+ ret = hsi_async_write(cl, msg);
+ if (ret < 0)
+ hsi_free_msg(msg);
+
+ return ret;
+}
+
+static int hsc_rx_set(struct hsi_client *cl, struct hsc_rx_config *rxc)
+{
+ struct hsi_config tmp;
+ int ret;
+
+ if ((rxc->mode != HSI_MODE_STREAM) && (rxc->mode != HSI_MODE_FRAME))
+ return -EINVAL;
+ if ((rxc->channels == 0) || (rxc->channels > HSC_DEVS))
+ return -EINVAL;
+ if (rxc->channels & (rxc->channels - 1))
+ return -EINVAL;
+ if ((rxc->flow != HSI_FLOW_SYNC) && (rxc->flow != HSI_FLOW_PIPE))
+ return -EINVAL;
+ tmp = cl->rx_cfg;
+ cl->rx_cfg.mode = rxc->mode;
+ cl->rx_cfg.channels = rxc->channels;
+ cl->rx_cfg.flow = rxc->flow;
+ ret = hsi_setup(cl);
+ if (ret < 0) {
+ cl->rx_cfg = tmp;
+ return ret;
+ }
+ if (rxc->mode == HSI_MODE_FRAME)
+ hsc_break_request(cl);
+
+ return ret;
+}
+
+static inline void hsc_rx_get(struct hsi_client *cl, struct hsc_rx_config *rxc)
+{
+ rxc->mode = cl->rx_cfg.mode;
+ rxc->channels = cl->rx_cfg.channels;
+ rxc->flow = cl->rx_cfg.flow;
+}
+
+static int hsc_tx_set(struct hsi_client *cl, struct hsc_tx_config *txc)
+{
+ struct hsi_config tmp;
+ int ret;
+
+ if ((txc->mode != HSI_MODE_STREAM) && (txc->mode != HSI_MODE_FRAME))
+ return -EINVAL;
+ if ((txc->channels == 0) || (txc->channels > HSC_DEVS))
+ return -EINVAL;
+ if (txc->channels & (txc->channels - 1))
+ return -EINVAL;
+ if ((txc->arb_mode != HSI_ARB_RR) && (txc->arb_mode != HSI_ARB_PRIO))
+ return -EINVAL;
+ tmp = cl->tx_cfg;
+ cl->tx_cfg.mode = txc->mode;
+ cl->tx_cfg.channels = txc->channels;
+ cl->tx_cfg.speed = txc->speed;
+ cl->tx_cfg.arb_mode = txc->arb_mode;
+ ret = hsi_setup(cl);
+ if (ret < 0) {
+ cl->tx_cfg = tmp;
+ return ret;
+ }
+
+ return ret;
+}
+
+static inline void hsc_tx_get(struct hsi_client *cl, struct hsc_tx_config *txc)
+{
+ txc->mode = cl->tx_cfg.mode;
+ txc->channels = cl->tx_cfg.channels;
+ txc->speed = cl->tx_cfg.speed;
+ txc->arb_mode = cl->tx_cfg.arb_mode;
+}
+
+static ssize_t hsc_read(struct file *file, char __user *buf, size_t len,
+ loff_t *ppos __maybe_unused)
+{
+ struct hsc_channel *channel = file->private_data;
+ struct hsi_msg *msg;
+ ssize_t ret;
+
+ if (len == 0)
+ return 0;
+ if (!IS_ALIGNED(len, sizeof(u32)))
+ return -EINVAL;
+ if (len > max_data_size)
+ len = max_data_size;
+ if (channel->ch >= channel->cl->rx_cfg.channels)
+ return -ECHRNG;
+ if (test_and_set_bit(HSC_CH_READ, &channel->flags))
+ return -EBUSY;
+ msg = hsc_get_first_msg(channel, &channel->free_msgs_list);
+ if (!msg) {
+ ret = -ENOSPC;
+ goto out;
+ }
+ hsc_msg_len_set(msg, len);
+ msg->complete = hsc_rx_completed;
+ msg->destructor = hsc_rx_msg_destructor;
+ ret = hsi_async_read(channel->cl, msg);
+ if (ret < 0) {
+ hsc_add_tail(channel, msg, &channel->free_msgs_list);
+ goto out;
+ }
+
+ ret = wait_event_interruptible(channel->rx_wait,
+ !list_empty(&channel->rx_msgs_queue));
+ if (ret < 0) {
+ clear_bit(HSC_CH_READ, &channel->flags);
+ hsi_flush(channel->cl);
+ return -EINTR;
+ }
+
+ msg = hsc_get_first_msg(channel, &channel->rx_msgs_queue);
+ if (msg) {
+ if (msg->status != HSI_STATUS_ERROR) {
+ ret = copy_to_user((void __user *)buf,
+ sg_virt(msg->sgt.sgl), hsc_msg_len_get(msg));
+ if (ret)
+ ret = -EFAULT;
+ else
+ ret = hsc_msg_len_get(msg);
+ } else {
+ ret = -EIO;
+ }
+ hsc_add_tail(channel, msg, &channel->free_msgs_list);
+ }
+out:
+ clear_bit(HSC_CH_READ, &channel->flags);
+
+ return ret;
+}
+
+static ssize_t hsc_write(struct file *file, const char __user *buf, size_t len,
+ loff_t *ppos __maybe_unused)
+{
+ struct hsc_channel *channel = file->private_data;
+ struct hsi_msg *msg;
+ ssize_t ret;
+
+ if ((len == 0) || !IS_ALIGNED(len, sizeof(u32)))
+ return -EINVAL;
+ if (len > max_data_size)
+ len = max_data_size;
+ if (channel->ch >= channel->cl->tx_cfg.channels)
+ return -ECHRNG;
+ if (test_and_set_bit(HSC_CH_WRITE, &channel->flags))
+ return -EBUSY;
+ msg = hsc_get_first_msg(channel, &channel->free_msgs_list);
+ if (!msg) {
+ clear_bit(HSC_CH_WRITE, &channel->flags);
+ return -ENOSPC;
+ }
+ if (copy_from_user(sg_virt(msg->sgt.sgl), (void __user *)buf, len)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ hsc_msg_len_set(msg, len);
+ msg->complete = hsc_tx_completed;
+ msg->destructor = hsc_tx_msg_destructor;
+ ret = hsi_async_write(channel->cl, msg);
+ if (ret < 0)
+ goto out;
+
+ ret = wait_event_interruptible(channel->tx_wait,
+ !list_empty(&channel->tx_msgs_queue));
+ if (ret < 0) {
+ clear_bit(HSC_CH_WRITE, &channel->flags);
+ hsi_flush(channel->cl);
+ return -EINTR;
+ }
+
+ msg = hsc_get_first_msg(channel, &channel->tx_msgs_queue);
+ if (msg) {
+ if (msg->status == HSI_STATUS_ERROR)
+ ret = -EIO;
+ else
+ ret = hsc_msg_len_get(msg);
+
+ hsc_add_tail(channel, msg, &channel->free_msgs_list);
+ }
+out:
+ clear_bit(HSC_CH_WRITE, &channel->flags);
+
+ return ret;
+}
+
+static long hsc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct hsc_channel *channel = file->private_data;
+ unsigned int state;
+ struct hsc_rx_config rxc;
+ struct hsc_tx_config txc;
+ long ret = 0;
+
+ switch (cmd) {
+ case HSC_RESET:
+ hsi_flush(channel->cl);
+ break;
+ case HSC_SET_PM:
+ if (copy_from_user(&state, (void __user *)arg, sizeof(state)))
+ return -EFAULT;
+ if (state == HSC_PM_DISABLE) {
+ if (test_and_set_bit(HSC_CH_WLINE, &channel->flags))
+ return -EINVAL;
+ ret = hsi_start_tx(channel->cl);
+ } else if (state == HSC_PM_ENABLE) {
+ if (!test_and_clear_bit(HSC_CH_WLINE, &channel->flags))
+ return -EINVAL;
+ ret = hsi_stop_tx(channel->cl);
+ } else {
+ ret = -EINVAL;
+ }
+ break;
+ case HSC_SEND_BREAK:
+ return hsc_break_send(channel->cl);
+ case HSC_SET_RX:
+ if (copy_from_user(&rxc, (void __user *)arg, sizeof(rxc)))
+ return -EFAULT;
+ return hsc_rx_set(channel->cl, &rxc);
+ case HSC_GET_RX:
+ hsc_rx_get(channel->cl, &rxc);
+ if (copy_to_user((void __user *)arg, &rxc, sizeof(rxc)))
+ return -EFAULT;
+ break;
+ case HSC_SET_TX:
+ if (copy_from_user(&txc, (void __user *)arg, sizeof(txc)))
+ return -EFAULT;
+ return hsc_tx_set(channel->cl, &txc);
+ case HSC_GET_TX:
+ hsc_tx_get(channel->cl, &txc);
+ if (copy_to_user((void __user *)arg, &txc, sizeof(txc)))
+ return -EFAULT;
+ break;
+ default:
+ return -ENOIOCTLCMD;
+ }
+
+ return ret;
+}
+
+static inline void __hsc_port_release(struct hsc_client_data *cl_data)
+{
+ BUG_ON(cl_data->usecnt == 0);
+
+ if (--cl_data->usecnt == 0) {
+ hsi_flush(cl_data->cl);
+ hsi_release_port(cl_data->cl);
+ }
+}
+
+static int hsc_open(struct inode *inode, struct file *file)
+{
+ struct hsc_client_data *cl_data;
+ struct hsc_channel *channel;
+ int ret = 0;
+
+ pr_debug("open, minor = %d\n", iminor(inode));
+
+ cl_data = container_of(inode->i_cdev, struct hsc_client_data, cdev);
+ mutex_lock(&cl_data->lock);
+ channel = cl_data->channels + (iminor(inode) & HSC_CH_MASK);
+
+ if (test_and_set_bit(HSC_CH_OPEN, &channel->flags)) {
+ ret = -EBUSY;
+ goto out;
+ }
+ /*
+ * Check if we have already claimed the port associated to the HSI
+ * client. If not then try to claim it, else increase its refcount
+ */
+ if (cl_data->usecnt == 0) {
+ ret = hsi_claim_port(cl_data->cl, 0);
+ if (ret < 0)
+ goto out;
+ hsi_setup(cl_data->cl);
+ }
+ cl_data->usecnt++;
+
+ ret = hsc_msgs_alloc(channel);
+ if (ret < 0) {
+ __hsc_port_release(cl_data);
+ goto out;
+ }
+
+ file->private_data = channel;
+ mutex_unlock(&cl_data->lock);
+
+ return ret;
+out:
+ mutex_unlock(&cl_data->lock);
+
+ return ret;
+}
+
+static int hsc_release(struct inode *inode __maybe_unused, struct file *file)
+{
+ struct hsc_channel *channel = file->private_data;
+ struct hsc_client_data *cl_data = channel->cl_data;
+
+ mutex_lock(&cl_data->lock);
+ file->private_data = NULL;
+ if (test_and_clear_bit(HSC_CH_WLINE, &channel->flags))
+ hsi_stop_tx(channel->cl);
+ __hsc_port_release(cl_data);
+ hsc_reset_list(channel, &channel->rx_msgs_queue);
+ hsc_reset_list(channel, &channel->tx_msgs_queue);
+ hsc_reset_list(channel, &channel->free_msgs_list);
+ clear_bit(HSC_CH_READ, &channel->flags);
+ clear_bit(HSC_CH_WRITE, &channel->flags);
+ clear_bit(HSC_CH_OPEN, &channel->flags);
+ wake_up(&channel->rx_wait);
+ wake_up(&channel->tx_wait);
+ mutex_unlock(&cl_data->lock);
+
+ return 0;
+}
+
+static const struct file_operations hsc_fops = {
+ .owner = THIS_MODULE,
+ .read = hsc_read,
+ .write = hsc_write,
+ .unlocked_ioctl = hsc_ioctl,
+ .open = hsc_open,
+ .release = hsc_release,
+};
+
+static void __devinit hsc_channel_init(struct hsc_channel *channel)
+{
+ init_waitqueue_head(&channel->rx_wait);
+ init_waitqueue_head(&channel->tx_wait);
+ spin_lock_init(&channel->lock);
+ INIT_LIST_HEAD(&channel->free_msgs_list);
+ INIT_LIST_HEAD(&channel->rx_msgs_queue);
+ INIT_LIST_HEAD(&channel->tx_msgs_queue);
+}
+
+static int __devinit hsc_probe(struct device *dev)
+{
+ const char devname[] = "hsi_char";
+ struct hsc_client_data *cl_data;
+ struct hsc_channel *channel;
+ struct hsi_client *cl = to_hsi_client(dev);
+ unsigned int hsc_baseminor;
+ dev_t hsc_dev;
+ int ret;
+ int i;
+
+ cl_data = kzalloc(sizeof(*cl_data), GFP_KERNEL);
+ if (!cl_data) {
+ dev_err(dev, "Could not allocate hsc_client_data\n");
+ return -ENOMEM;
+ }
+ hsc_baseminor = HSC_BASEMINOR(hsi_id(cl), hsi_port_id(cl));
+ if (!hsc_major) {
+ ret = alloc_chrdev_region(&hsc_dev, hsc_baseminor,
+ HSC_DEVS, devname);
+ if (ret > 0)
+ hsc_major = MAJOR(hsc_dev);
+ } else {
+ hsc_dev = MKDEV(hsc_major, hsc_baseminor);
+ ret = register_chrdev_region(hsc_dev, HSC_DEVS, devname);
+ }
+ if (ret < 0) {
+ dev_err(dev, "Device %s allocation failed %d\n",
+ hsc_major ? "minor" : "major", ret);
+ goto out1;
+ }
+ mutex_init(&cl_data->lock);
+ hsi_client_set_drvdata(cl, cl_data);
+ cdev_init(&cl_data->cdev, &hsc_fops);
+ cl_data->cdev.owner = THIS_MODULE;
+ cl_data->cl = cl;
+ for (i = 0, channel = cl_data->channels; i < HSC_DEVS; i++, channel++) {
+ hsc_channel_init(channel);
+ channel->ch = i;
+ channel->cl = cl;
+ channel->cl_data = cl_data;
+ }
+
+ /* 1 hsi client -> N char devices (one for each channel) */
+ ret = cdev_add(&cl_data->cdev, hsc_dev, HSC_DEVS);
+ if (ret) {
+ dev_err(dev, "Could not add char device %d\n", ret);
+ goto out2;
+ }
+
+ return 0;
+out2:
+ unregister_chrdev_region(hsc_dev, HSC_DEVS);
+out1:
+ kfree(cl_data);
+
+ return ret;
+}
+
+static int __devexit hsc_remove(struct device *dev)
+{
+ struct hsi_client *cl = to_hsi_client(dev);
+ struct hsc_client_data *cl_data = hsi_client_drvdata(cl);
+ dev_t hsc_dev = cl_data->cdev.dev;
+
+ cdev_del(&cl_data->cdev);
+ unregister_chrdev_region(hsc_dev, HSC_DEVS);
+ hsi_client_set_drvdata(cl, NULL);
+ kfree(cl_data);
+
+ return 0;
+}
+
+static struct hsi_client_driver hsc_driver = {
+ .driver = {
+ .name = "hsi_char",
+ .owner = THIS_MODULE,
+ .probe = hsc_probe,
+ .remove = __devexit_p(hsc_remove),
+ },
+};
+
+static int __init hsc_init(void)
+{
+ int ret;
+
+ if ((max_data_size < 4) || (max_data_size > 0x10000) ||
+ (max_data_size & (max_data_size - 1))) {
+ pr_err("Invalid max read/write data size");
+ return -EINVAL;
+ }
+
+ ret = hsi_register_client_driver(&hsc_driver);
+ if (ret) {
+ pr_err("Error while registering HSI/SSI driver %d", ret);
+ return ret;
+ }
+
+ pr_info("HSI/SSI char device loaded\n");
+
+ return 0;
+}
+module_init(hsc_init);
+
+static void __exit hsc_exit(void)
+{
+ hsi_unregister_client_driver(&hsc_driver);
+ pr_info("HSI char device removed\n");
+}
+module_exit(hsc_exit);
+
+MODULE_AUTHOR("Andras Domokos <andras.domokos@nokia.com>");
+MODULE_ALIAS("hsi:hsi_char");
+MODULE_DESCRIPTION("HSI character device");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/hsi/hsi.c b/drivers/hsi/hsi.c
new file mode 100644
index 000000000000..4e2d79b79334
--- /dev/null
+++ b/drivers/hsi/hsi.c
@@ -0,0 +1,494 @@
+/*
+ * HSI core.
+ *
+ * Copyright (C) 2010 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Carlos Chinea <carlos.chinea@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+#include <linux/hsi/hsi.h>
+#include <linux/compiler.h>
+#include <linux/rwsem.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/kobject.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include "hsi_core.h"
+
+static struct device_type hsi_ctrl = {
+ .name = "hsi_controller",
+};
+
+static struct device_type hsi_cl = {
+ .name = "hsi_client",
+};
+
+static struct device_type hsi_port = {
+ .name = "hsi_port",
+};
+
+static ssize_t modalias_show(struct device *dev,
+ struct device_attribute *a __maybe_unused, char *buf)
+{
+ return sprintf(buf, "hsi:%s\n", dev_name(dev));
+}
+
+static struct device_attribute hsi_bus_dev_attrs[] = {
+ __ATTR_RO(modalias),
+ __ATTR_NULL,
+};
+
+static int hsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ if (dev->type == &hsi_cl)
+ add_uevent_var(env, "MODALIAS=hsi:%s", dev_name(dev));
+
+ return 0;
+}
+
+static int hsi_bus_match(struct device *dev, struct device_driver *driver)
+{
+ return strcmp(dev_name(dev), driver->name) == 0;
+}
+
+static struct bus_type hsi_bus_type = {
+ .name = "hsi",
+ .dev_attrs = hsi_bus_dev_attrs,
+ .match = hsi_bus_match,
+ .uevent = hsi_bus_uevent,
+};
+
+static void hsi_client_release(struct device *dev)
+{
+ kfree(to_hsi_client(dev));
+}
+
+static void hsi_new_client(struct hsi_port *port, struct hsi_board_info *info)
+{
+ struct hsi_client *cl;
+ unsigned long flags;
+
+ cl = kzalloc(sizeof(*cl), GFP_KERNEL);
+ if (!cl)
+ return;
+ cl->device.type = &hsi_cl;
+ cl->tx_cfg = info->tx_cfg;
+ cl->rx_cfg = info->rx_cfg;
+ cl->device.bus = &hsi_bus_type;
+ cl->device.parent = &port->device;
+ cl->device.release = hsi_client_release;
+ dev_set_name(&cl->device, info->name);
+ cl->device.platform_data = info->platform_data;
+ spin_lock_irqsave(&port->clock, flags);
+ list_add_tail(&cl->link, &port->clients);
+ spin_unlock_irqrestore(&port->clock, flags);
+ if (info->archdata)
+ cl->device.archdata = *info->archdata;
+ if (device_register(&cl->device) < 0) {
+ pr_err("hsi: failed to register client: %s\n", info->name);
+ kfree(cl);
+ }
+}
+
+static void hsi_scan_board_info(struct hsi_controller *hsi)
+{
+ struct hsi_cl_info *cl_info;
+ struct hsi_port *p;
+
+ list_for_each_entry(cl_info, &hsi_board_list, list)
+ if (cl_info->info.hsi_id == hsi->id) {
+ p = hsi_find_port_num(hsi, cl_info->info.port);
+ if (!p)
+ continue;
+ hsi_new_client(p, &cl_info->info);
+ }
+}
+
+static int hsi_remove_client(struct device *dev, void *data __maybe_unused)
+{
+ struct hsi_client *cl = to_hsi_client(dev);
+ struct hsi_port *port = to_hsi_port(dev->parent);
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->clock, flags);
+ list_del(&cl->link);
+ spin_unlock_irqrestore(&port->clock, flags);
+ device_unregister(dev);
+
+ return 0;
+}
+
+static int hsi_remove_port(struct device *dev, void *data __maybe_unused)
+{
+ device_for_each_child(dev, NULL, hsi_remove_client);
+ device_unregister(dev);
+
+ return 0;
+}
+
+static void hsi_controller_release(struct device *dev __maybe_unused)
+{
+}
+
+static void hsi_port_release(struct device *dev __maybe_unused)
+{
+}
+
+/**
+ * hsi_unregister_controller - Unregister an HSI controller
+ * @hsi: The HSI controller to register
+ */
+void hsi_unregister_controller(struct hsi_controller *hsi)
+{
+ device_for_each_child(&hsi->device, NULL, hsi_remove_port);
+ device_unregister(&hsi->device);
+}
+EXPORT_SYMBOL_GPL(hsi_unregister_controller);
+
+/**
+ * hsi_register_controller - Register an HSI controller and its ports
+ * @hsi: The HSI controller to register
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int hsi_register_controller(struct hsi_controller *hsi)
+{
+ unsigned int i;
+ int err;
+
+ hsi->device.type = &hsi_ctrl;
+ hsi->device.bus = &hsi_bus_type;
+ hsi->device.release = hsi_controller_release;
+ err = device_register(&hsi->device);
+ if (err < 0)
+ return err;
+ for (i = 0; i < hsi->num_ports; i++) {
+ hsi->port[i].device.parent = &hsi->device;
+ hsi->port[i].device.bus = &hsi_bus_type;
+ hsi->port[i].device.release = hsi_port_release;
+ hsi->port[i].device.type = &hsi_port;
+ INIT_LIST_HEAD(&hsi->port[i].clients);
+ spin_lock_init(&hsi->port[i].clock);
+ err = device_register(&hsi->port[i].device);
+ if (err < 0)
+ goto out;
+ }
+ /* Populate HSI bus with HSI clients */
+ hsi_scan_board_info(hsi);
+
+ return 0;
+out:
+ hsi_unregister_controller(hsi);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(hsi_register_controller);
+
+/**
+ * hsi_register_client_driver - Register an HSI client to the HSI bus
+ * @drv: HSI client driver to register
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int hsi_register_client_driver(struct hsi_client_driver *drv)
+{
+ drv->driver.bus = &hsi_bus_type;
+
+ return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(hsi_register_client_driver);
+
+static inline int hsi_dummy_msg(struct hsi_msg *msg __maybe_unused)
+{
+ return 0;
+}
+
+static inline int hsi_dummy_cl(struct hsi_client *cl __maybe_unused)
+{
+ return 0;
+}
+
+/**
+ * hsi_alloc_controller - Allocate an HSI controller and its ports
+ * @n_ports: Number of ports on the HSI controller
+ * @flags: Kernel allocation flags
+ *
+ * Return NULL on failure or a pointer to an hsi_controller on success.
+ */
+struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags)
+{
+ struct hsi_controller *hsi;
+ struct hsi_port *port;
+ unsigned int i;
+
+ if (!n_ports)
+ return NULL;
+
+ port = kzalloc(sizeof(*port)*n_ports, flags);
+ if (!port)
+ return NULL;
+ hsi = kzalloc(sizeof(*hsi), flags);
+ if (!hsi)
+ goto out;
+ for (i = 0; i < n_ports; i++) {
+ dev_set_name(&port[i].device, "port%d", i);
+ port[i].num = i;
+ port[i].async = hsi_dummy_msg;
+ port[i].setup = hsi_dummy_cl;
+ port[i].flush = hsi_dummy_cl;
+ port[i].start_tx = hsi_dummy_cl;
+ port[i].stop_tx = hsi_dummy_cl;
+ port[i].release = hsi_dummy_cl;
+ mutex_init(&port[i].lock);
+ }
+ hsi->num_ports = n_ports;
+ hsi->port = port;
+
+ return hsi;
+out:
+ kfree(port);
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(hsi_alloc_controller);
+
+/**
+ * hsi_free_controller - Free an HSI controller
+ * @hsi: Pointer to HSI controller
+ */
+void hsi_free_controller(struct hsi_controller *hsi)
+{
+ if (!hsi)
+ return;
+
+ kfree(hsi->port);
+ kfree(hsi);
+}
+EXPORT_SYMBOL_GPL(hsi_free_controller);
+
+/**
+ * hsi_free_msg - Free an HSI message
+ * @msg: Pointer to the HSI message
+ *
+ * Client is responsible to free the buffers pointed by the scatterlists.
+ */
+void hsi_free_msg(struct hsi_msg *msg)
+{
+ if (!msg)
+ return;
+ sg_free_table(&msg->sgt);
+ kfree(msg);
+}
+EXPORT_SYMBOL_GPL(hsi_free_msg);
+
+/**
+ * hsi_alloc_msg - Allocate an HSI message
+ * @nents: Number of memory entries
+ * @flags: Kernel allocation flags
+ *
+ * nents can be 0. This mainly makes sense for read transfer.
+ * In that case, HSI drivers will call the complete callback when
+ * there is data to be read without consuming it.
+ *
+ * Return NULL on failure or a pointer to an hsi_msg on success.
+ */
+struct hsi_msg *hsi_alloc_msg(unsigned int nents, gfp_t flags)
+{
+ struct hsi_msg *msg;
+ int err;
+
+ msg = kzalloc(sizeof(*msg), flags);
+ if (!msg)
+ return NULL;
+
+ if (!nents)
+ return msg;
+
+ err = sg_alloc_table(&msg->sgt, nents, flags);
+ if (unlikely(err)) {
+ kfree(msg);
+ msg = NULL;
+ }
+
+ return msg;
+}
+EXPORT_SYMBOL_GPL(hsi_alloc_msg);
+
+/**
+ * hsi_async - Submit an HSI transfer to the controller
+ * @cl: HSI client sending the transfer
+ * @msg: The HSI transfer passed to controller
+ *
+ * The HSI message must have the channel, ttype, complete and destructor
+ * fields set beforehand. If nents > 0 then the client has to initialize
+ * also the scatterlists to point to the buffers to write to or read from.
+ *
+ * HSI controllers relay on pre-allocated buffers from their clients and they
+ * do not allocate buffers on their own.
+ *
+ * Once the HSI message transfer finishes, the HSI controller calls the
+ * complete callback with the status and actual_len fields of the HSI message
+ * updated. The complete callback can be called before returning from
+ * hsi_async.
+ *
+ * Returns -errno on failure or 0 on success
+ */
+int hsi_async(struct hsi_client *cl, struct hsi_msg *msg)
+{
+ struct hsi_port *port = hsi_get_port(cl);
+
+ if (!hsi_port_claimed(cl))
+ return -EACCES;
+
+ WARN_ON_ONCE(!msg->destructor || !msg->complete);
+ msg->cl = cl;
+
+ return port->async(msg);
+}
+EXPORT_SYMBOL_GPL(hsi_async);
+
+/**
+ * hsi_claim_port - Claim the HSI client's port
+ * @cl: HSI client that wants to claim its port
+ * @share: Flag to indicate if the client wants to share the port or not.
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int hsi_claim_port(struct hsi_client *cl, unsigned int share)
+{
+ struct hsi_port *port = hsi_get_port(cl);
+ int err = 0;
+
+ mutex_lock(&port->lock);
+ if ((port->claimed) && (!port->shared || !share)) {
+ err = -EBUSY;
+ goto out;
+ }
+ if (!try_module_get(to_hsi_controller(port->device.parent)->owner)) {
+ err = -ENODEV;
+ goto out;
+ }
+ port->claimed++;
+ port->shared = !!share;
+ cl->pclaimed = 1;
+out:
+ mutex_unlock(&port->lock);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(hsi_claim_port);
+
+/**
+ * hsi_release_port - Release the HSI client's port
+ * @cl: HSI client which previously claimed its port
+ */
+void hsi_release_port(struct hsi_client *cl)
+{
+ struct hsi_port *port = hsi_get_port(cl);
+
+ mutex_lock(&port->lock);
+ /* Allow HW driver to do some cleanup */
+ port->release(cl);
+ if (cl->pclaimed)
+ port->claimed--;
+ BUG_ON(port->claimed < 0);
+ cl->pclaimed = 0;
+ if (!port->claimed)
+ port->shared = 0;
+ module_put(to_hsi_controller(port->device.parent)->owner);
+ mutex_unlock(&port->lock);
+}
+EXPORT_SYMBOL_GPL(hsi_release_port);
+
+static int hsi_start_rx(struct hsi_client *cl, void *data __maybe_unused)
+{
+ if (cl->hsi_start_rx)
+ (*cl->hsi_start_rx)(cl);
+
+ return 0;
+}
+
+static int hsi_stop_rx(struct hsi_client *cl, void *data __maybe_unused)
+{
+ if (cl->hsi_stop_rx)
+ (*cl->hsi_stop_rx)(cl);
+
+ return 0;
+}
+
+static int hsi_port_for_each_client(struct hsi_port *port, void *data,
+ int (*fn)(struct hsi_client *cl, void *data))
+{
+ struct hsi_client *cl;
+
+ spin_lock(&port->clock);
+ list_for_each_entry(cl, &port->clients, link) {
+ spin_unlock(&port->clock);
+ (*fn)(cl, data);
+ spin_lock(&port->clock);
+ }
+ spin_unlock(&port->clock);
+
+ return 0;
+}
+
+/**
+ * hsi_event -Notifies clients about port events
+ * @port: Port where the event occurred
+ * @event: The event type
+ *
+ * Clients should not be concerned about wake line behavior. However, due
+ * to a race condition in HSI HW protocol, clients need to be notified
+ * about wake line changes, so they can implement a workaround for it.
+ *
+ * Events:
+ * HSI_EVENT_START_RX - Incoming wake line high
+ * HSI_EVENT_STOP_RX - Incoming wake line down
+ */
+void hsi_event(struct hsi_port *port, unsigned int event)
+{
+ int (*fn)(struct hsi_client *cl, void *data);
+
+ switch (event) {
+ case HSI_EVENT_START_RX:
+ fn = hsi_start_rx;
+ break;
+ case HSI_EVENT_STOP_RX:
+ fn = hsi_stop_rx;
+ break;
+ default:
+ return;
+ }
+ hsi_port_for_each_client(port, NULL, fn);
+}
+EXPORT_SYMBOL_GPL(hsi_event);
+
+static int __init hsi_init(void)
+{
+ return bus_register(&hsi_bus_type);
+}
+postcore_initcall(hsi_init);
+
+static void __exit hsi_exit(void)
+{
+ bus_unregister(&hsi_bus_type);
+}
+module_exit(hsi_exit);
+
+MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>");
+MODULE_DESCRIPTION("High-speed Synchronous Serial Interface (HSI) framework");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/hsi/hsi_boardinfo.c b/drivers/hsi/hsi_boardinfo.c
new file mode 100644
index 000000000000..e56bc6da5f98
--- /dev/null
+++ b/drivers/hsi/hsi_boardinfo.c
@@ -0,0 +1,62 @@
+/*
+ * HSI clients registration interface
+ *
+ * Copyright (C) 2010 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Carlos Chinea <carlos.chinea@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+#include <linux/hsi/hsi.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include "hsi_core.h"
+
+/*
+ * hsi_board_list is only used internally by the HSI framework.
+ * No one else is allowed to make use of it.
+ */
+LIST_HEAD(hsi_board_list);
+EXPORT_SYMBOL_GPL(hsi_board_list);
+
+/**
+ * hsi_register_board_info - Register HSI clients information
+ * @info: Array of HSI clients on the board
+ * @len: Length of the array
+ *
+ * HSI clients are statically declared and registered on board files.
+ *
+ * HSI clients will be automatically registered to the HSI bus once the
+ * controller and the port where the clients wishes to attach are registered
+ * to it.
+ *
+ * Return -errno on failure, 0 on success.
+ */
+int __init hsi_register_board_info(struct hsi_board_info const *info,
+ unsigned int len)
+{
+ struct hsi_cl_info *cl_info;
+
+ cl_info = kzalloc(sizeof(*cl_info) * len, GFP_KERNEL);
+ if (!cl_info)
+ return -ENOMEM;
+
+ for (; len; len--, info++, cl_info++) {
+ cl_info->info = *info;
+ list_add_tail(&cl_info->list, &hsi_board_list);
+ }
+
+ return 0;
+}
diff --git a/drivers/hsi/hsi_core.h b/drivers/hsi/hsi_core.h
new file mode 100644
index 000000000000..ab5c2fb175fd
--- /dev/null
+++ b/drivers/hsi/hsi_core.h
@@ -0,0 +1,35 @@
+/*
+ * HSI framework internal interfaces,
+ *
+ * Copyright (C) 2010 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Carlos Chinea <carlos.chinea@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#ifndef __LINUX_HSI_CORE_H__
+#define __LINUX_HSI_CORE_H__
+
+#include <linux/hsi/hsi.h>
+
+struct hsi_cl_info {
+ struct list_head list;
+ struct hsi_board_info info;
+};
+
+extern struct list_head hsi_board_list;
+
+#endif /* __LINUX_HSI_CORE_H__ */