Fixed MTP to work with TWRP

drivers/hsi/Kconfig

@@ -0,0 +1,20 @@
+#
+# 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/controllers/Kconfig"
+source "drivers/hsi/clients/Kconfig"
+
+endif # HSI

drivers/hsi/Makefile

@@ -0,0 +1,7 @@
+#
+# Makefile for HSI
+#
+obj-$(CONFIG_HSI_BOARDINFO)	+= hsi_boardinfo.o
+obj-$(CONFIG_HSI)		+= hsi.o
+obj-y				+= controllers/
+obj-y				+= clients/

drivers/hsi/clients/Kconfig

@@ -0,0 +1,30 @@
+#
+# HSI clients configuration
+#
+
+comment "HSI clients"
+
+config NOKIA_MODEM
+	tristate "Nokia Modem"
+	depends on HSI && SSI_PROTOCOL
+	help
+	Say Y here if you want to add support for the modem on Nokia
+	N900 (Nokia RX-51) hardware.
+
+	If unsure, say N.
+
+config SSI_PROTOCOL
+	tristate "SSI protocol"
+	depends on HSI && PHONET && OMAP_SSI
+	help
+	If you say Y here, you will enable the SSI protocol aka McSAAB.
+
+	If unsure, say N.
+
+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.

drivers/hsi/clients/Makefile

@@ -0,0 +1,7 @@
+#
+# Makefile for HSI clients
+#
+
+obj-$(CONFIG_NOKIA_MODEM)	+= nokia-modem.o
+obj-$(CONFIG_SSI_PROTOCOL)	+= ssi_protocol.o
+obj-$(CONFIG_HSI_CHAR)		+= hsi_char.o

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, 0);
+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.num_hw_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.num_hw_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.num_hw_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.num_hw_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.num_hw_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.num_hw_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 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 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 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	= 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");

drivers/hsi/clients/nokia-modem.c

@@ -0,0 +1,285 @@
+/*
+ * nokia-modem.c
+ *
+ * HSI client driver for Nokia N900 modem.
+ *
+ * Copyright (C) 2014 Sebastian Reichel <sre@kernel.org>
+ *
+ * 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/gpio/consumer.h>
+#include <linux/hsi/hsi.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_gpio.h>
+#include <linux/hsi/ssi_protocol.h>
+
+static unsigned int pm;
+module_param(pm, int, 0400);
+MODULE_PARM_DESC(pm,
+	"Enable power management (0=disabled, 1=userland based [default])");
+
+struct nokia_modem_gpio {
+	struct gpio_desc	*gpio;
+	const char		*name;
+};
+
+struct nokia_modem_device {
+	struct tasklet_struct	nokia_modem_rst_ind_tasklet;
+	int			nokia_modem_rst_ind_irq;
+	struct device		*device;
+	struct nokia_modem_gpio	*gpios;
+	int			gpio_amount;
+	struct hsi_client	*ssi_protocol;
+};
+
+static void do_nokia_modem_rst_ind_tasklet(unsigned long data)
+{
+	struct nokia_modem_device *modem = (struct nokia_modem_device *)data;
+
+	if (!modem)
+		return;
+
+	dev_info(modem->device, "CMT rst line change detected\n");
+
+	if (modem->ssi_protocol)
+		ssip_reset_event(modem->ssi_protocol);
+}
+
+static irqreturn_t nokia_modem_rst_ind_isr(int irq, void *data)
+{
+	struct nokia_modem_device *modem = (struct nokia_modem_device *)data;
+
+	tasklet_schedule(&modem->nokia_modem_rst_ind_tasklet);
+
+	return IRQ_HANDLED;
+}
+
+static void nokia_modem_gpio_unexport(struct device *dev)
+{
+	struct nokia_modem_device *modem = dev_get_drvdata(dev);
+	int i;
+
+	for (i = 0; i < modem->gpio_amount; i++) {
+		sysfs_remove_link(&dev->kobj, modem->gpios[i].name);
+		gpiod_unexport(modem->gpios[i].gpio);
+	}
+}
+
+static int nokia_modem_gpio_probe(struct device *dev)
+{
+	struct device_node *np = dev->of_node;
+	struct nokia_modem_device *modem = dev_get_drvdata(dev);
+	int gpio_count, gpio_name_count, i, err;
+
+	gpio_count = of_gpio_count(np);
+
+	if (gpio_count < 0) {
+		dev_err(dev, "missing gpios: %d\n", gpio_count);
+		return gpio_count;
+	}
+
+	gpio_name_count = of_property_count_strings(np, "gpio-names");
+
+	if (gpio_count != gpio_name_count) {
+		dev_err(dev, "number of gpios does not equal number of gpio names\n");
+		return -EINVAL;
+	}
+
+	modem->gpios = devm_kzalloc(dev, gpio_count *
+				sizeof(struct nokia_modem_gpio), GFP_KERNEL);
+	if (!modem->gpios) {
+		dev_err(dev, "Could not allocate memory for gpios\n");
+		return -ENOMEM;
+	}
+
+	modem->gpio_amount = gpio_count;
+
+	for (i = 0; i < gpio_count; i++) {
+		modem->gpios[i].gpio = devm_gpiod_get_index(dev, NULL, i);
+		if (IS_ERR(modem->gpios[i].gpio)) {
+			dev_err(dev, "Could not get gpio %d\n", i);
+			return PTR_ERR(modem->gpios[i].gpio);
+		}
+
+		err = of_property_read_string_index(np, "gpio-names", i,
+						&(modem->gpios[i].name));
+		if (err) {
+			dev_err(dev, "Could not get gpio name %d\n", i);
+			return err;
+		}
+
+		err = gpiod_direction_output(modem->gpios[i].gpio, 0);
+		if (err)
+			return err;
+
+		err = gpiod_export(modem->gpios[i].gpio, 0);
+		if (err)
+			return err;
+
+		err = gpiod_export_link(dev, modem->gpios[i].name,
+							modem->gpios[i].gpio);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int nokia_modem_probe(struct device *dev)
+{
+	struct device_node *np;
+	struct nokia_modem_device *modem;
+	struct hsi_client *cl = to_hsi_client(dev);
+	struct hsi_port *port = hsi_get_port(cl);
+	int irq, pflags, err;
+	struct hsi_board_info ssip;
+
+	np = dev->of_node;
+	if (!np) {
+		dev_err(dev, "device tree node not found\n");
+		return -ENXIO;
+	}
+
+	modem = devm_kzalloc(dev, sizeof(*modem), GFP_KERNEL);
+	if (!modem) {
+		dev_err(dev, "Could not allocate memory for nokia_modem_device\n");
+		return -ENOMEM;
+	}
+	dev_set_drvdata(dev, modem);
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq < 0) {
+		dev_err(dev, "Invalid rst_ind interrupt (%d)\n", irq);
+		return irq;
+	}
+	modem->nokia_modem_rst_ind_irq = irq;
+	pflags = irq_get_trigger_type(irq);
+
+	tasklet_init(&modem->nokia_modem_rst_ind_tasklet,
+			do_nokia_modem_rst_ind_tasklet, (unsigned long)modem);
+	err = devm_request_irq(dev, irq, nokia_modem_rst_ind_isr,
+				IRQF_DISABLED | pflags, "modem_rst_ind", modem);
+	if (err < 0) {
+		dev_err(dev, "Request rst_ind irq(%d) failed (flags %d)\n",
+								irq, pflags);
+		return err;
+	}
+	enable_irq_wake(irq);
+
+	if(pm) {
+		err = nokia_modem_gpio_probe(dev);
+		if (err < 0) {
+			dev_err(dev, "Could not probe GPIOs\n");
+			goto error1;
+		}
+	}
+
+	ssip.name = "ssi-protocol";
+	ssip.tx_cfg = cl->tx_cfg;
+	ssip.rx_cfg = cl->rx_cfg;
+	ssip.platform_data = NULL;
+	ssip.archdata = NULL;
+
+	modem->ssi_protocol = hsi_new_client(port, &ssip);
+	if (!modem->ssi_protocol) {
+		dev_err(dev, "Could not register ssi-protocol device\n");
+		goto error2;
+	}
+
+	err = device_attach(&modem->ssi_protocol->device);
+	if (err == 0) {
+		dev_err(dev, "Missing ssi-protocol driver\n");
+		err = -EPROBE_DEFER;
+		goto error3;
+	} else if (err < 0) {
+		dev_err(dev, "Could not load ssi-protocol driver (%d)\n", err);
+		goto error3;
+	}
+
+	/* TODO: register cmt-speech hsi client */
+
+	dev_info(dev, "Registered Nokia HSI modem\n");
+
+	return 0;
+
+error3:
+	hsi_remove_client(&modem->ssi_protocol->device, NULL);
+error2:
+	nokia_modem_gpio_unexport(dev);
+error1:
+	disable_irq_wake(modem->nokia_modem_rst_ind_irq);
+	tasklet_kill(&modem->nokia_modem_rst_ind_tasklet);
+
+	return err;
+}
+
+static int nokia_modem_remove(struct device *dev)
+{
+	struct nokia_modem_device *modem = dev_get_drvdata(dev);
+
+	if (!modem)
+		return 0;
+
+	if (modem->ssi_protocol) {
+		hsi_remove_client(&modem->ssi_protocol->device, NULL);
+		modem->ssi_protocol = NULL;
+	}
+
+	nokia_modem_gpio_unexport(dev);
+	dev_set_drvdata(dev, NULL);
+	disable_irq_wake(modem->nokia_modem_rst_ind_irq);
+	tasklet_kill(&modem->nokia_modem_rst_ind_tasklet);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id nokia_modem_of_match[] = {
+	{ .compatible = "nokia,n900-modem", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, nokia_modem_of_match);
+#endif
+
+static struct hsi_client_driver nokia_modem_driver = {
+	.driver = {
+		.name	= "nokia-modem",
+		.owner	= THIS_MODULE,
+		.probe	= nokia_modem_probe,
+		.remove	= nokia_modem_remove,
+		.of_match_table = of_match_ptr(nokia_modem_of_match),
+	},
+};
+
+static int __init nokia_modem_init(void)
+{
+	return hsi_register_client_driver(&nokia_modem_driver);
+}
+module_init(nokia_modem_init);
+
+static void __exit nokia_modem_exit(void)
+{
+	hsi_unregister_client_driver(&nokia_modem_driver);
+}
+module_exit(nokia_modem_exit);
+
+MODULE_ALIAS("hsi:nokia-modem");
+MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
+MODULE_DESCRIPTION("HSI driver module for Nokia N900 Modem");
+MODULE_LICENSE("GPL");

drivers/hsi/controllers/Kconfig

@@ -0,0 +1,19 @@
+#
+# HSI controllers configuration
+#
+comment "HSI controllers"
+
+config OMAP_SSI
+	tristate "OMAP SSI hardware driver"
+	depends on HSI && OF && (ARCH_OMAP3 || (ARM && COMPILE_TEST))
+	---help---
+	  SSI is a legacy version of HSI. It is usually used to connect
+	  an application engine with a cellular modem.
+	  If you say Y here, you will enable the OMAP SSI hardware driver.
+
+	  If unsure, say N.
+
+config OMAP_SSI_PORT
+	tristate
+	default m if OMAP_SSI=m
+	default y if OMAP_SSI=y

drivers/hsi/controllers/Makefile

@@ -0,0 +1,6 @@
+#
+# Makefile for HSI controllers drivers
+#
+
+obj-$(CONFIG_OMAP_SSI)		+= omap_ssi.o
+obj-$(CONFIG_OMAP_SSI_PORT)	+= omap_ssi_port.o

drivers/hsi/controllers/omap_ssi.c

@@ -0,0 +1,625 @@
+/* OMAP SSI driver.
+ *
+ * Copyright (C) 2010 Nokia Corporation. All rights reserved.
+ * Copyright (C) 2014 Sebastian Reichel <sre@kernel.org>
+ *
+ * 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/compiler.h>
+#include <linux/err.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/delay.h>
+#include <linux/seq_file.h>
+#include <linux/scatterlist.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/debugfs.h>
+#include <linux/pm_runtime.h>
+#include <linux/of_platform.h>
+#include <linux/hsi/hsi.h>
+#include <linux/idr.h>
+
+#include "omap_ssi_regs.h"
+#include "omap_ssi.h"
+
+/* For automatically allocated device IDs */
+static DEFINE_IDA(platform_omap_ssi_ida);
+
+#ifdef CONFIG_DEBUG_FS
+static int ssi_debug_show(struct seq_file *m, void *p __maybe_unused)
+{
+	struct hsi_controller *ssi = m->private;
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+	void __iomem *sys = omap_ssi->sys;
+
+	pm_runtime_get_sync(ssi->device.parent);
+	seq_printf(m, "REVISION\t: 0x%08x\n",  readl(sys + SSI_REVISION_REG));
+	seq_printf(m, "SYSCONFIG\t: 0x%08x\n", readl(sys + SSI_SYSCONFIG_REG));
+	seq_printf(m, "SYSSTATUS\t: 0x%08x\n", readl(sys + SSI_SYSSTATUS_REG));
+	pm_runtime_put_sync(ssi->device.parent);
+
+	return 0;
+}
+
+static int ssi_debug_gdd_show(struct seq_file *m, void *p __maybe_unused)
+{
+	struct hsi_controller *ssi = m->private;
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+	void __iomem *gdd = omap_ssi->gdd;
+	void __iomem *sys = omap_ssi->sys;
+	int lch;
+
+	pm_runtime_get_sync(ssi->device.parent);
+
+	seq_printf(m, "GDD_MPU_STATUS\t: 0x%08x\n",
+		readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG));
+	seq_printf(m, "GDD_MPU_ENABLE\t: 0x%08x\n\n",
+		readl(sys + SSI_GDD_MPU_IRQ_ENABLE_REG));
+	seq_printf(m, "HW_ID\t\t: 0x%08x\n",
+				readl(gdd + SSI_GDD_HW_ID_REG));
+	seq_printf(m, "PPORT_ID\t: 0x%08x\n",
+				readl(gdd + SSI_GDD_PPORT_ID_REG));
+	seq_printf(m, "MPORT_ID\t: 0x%08x\n",
+				readl(gdd + SSI_GDD_MPORT_ID_REG));
+	seq_printf(m, "TEST\t\t: 0x%08x\n",
+				readl(gdd + SSI_GDD_TEST_REG));
+	seq_printf(m, "GCR\t\t: 0x%08x\n",
+				readl(gdd + SSI_GDD_GCR_REG));
+
+	for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
+		seq_printf(m, "\nGDD LCH %d\n=========\n", lch);
+		seq_printf(m, "CSDP\t\t: 0x%04x\n",
+				readw(gdd + SSI_GDD_CSDP_REG(lch)));
+		seq_printf(m, "CCR\t\t: 0x%04x\n",
+				readw(gdd + SSI_GDD_CCR_REG(lch)));
+		seq_printf(m, "CICR\t\t: 0x%04x\n",
+				readw(gdd + SSI_GDD_CICR_REG(lch)));
+		seq_printf(m, "CSR\t\t: 0x%04x\n",
+				readw(gdd + SSI_GDD_CSR_REG(lch)));
+		seq_printf(m, "CSSA\t\t: 0x%08x\n",
+				readl(gdd + SSI_GDD_CSSA_REG(lch)));
+		seq_printf(m, "CDSA\t\t: 0x%08x\n",
+				readl(gdd + SSI_GDD_CDSA_REG(lch)));
+		seq_printf(m, "CEN\t\t: 0x%04x\n",
+				readw(gdd + SSI_GDD_CEN_REG(lch)));
+		seq_printf(m, "CSAC\t\t: 0x%04x\n",
+				readw(gdd + SSI_GDD_CSAC_REG(lch)));
+		seq_printf(m, "CDAC\t\t: 0x%04x\n",
+				readw(gdd + SSI_GDD_CDAC_REG(lch)));
+		seq_printf(m, "CLNK_CTRL\t: 0x%04x\n",
+				readw(gdd + SSI_GDD_CLNK_CTRL_REG(lch)));
+	}
+
+	pm_runtime_put_sync(ssi->device.parent);
+
+	return 0;
+}
+
+static int ssi_regs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, ssi_debug_show, inode->i_private);
+}
+
+static int ssi_gdd_regs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, ssi_debug_gdd_show, inode->i_private);
+}
+
+static const struct file_operations ssi_regs_fops = {
+	.open		= ssi_regs_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static const struct file_operations ssi_gdd_regs_fops = {
+	.open		= ssi_gdd_regs_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static int __init ssi_debug_add_ctrl(struct hsi_controller *ssi)
+{
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+	struct dentry *dir;
+
+	/* SSI controller */
+	omap_ssi->dir = debugfs_create_dir(dev_name(&ssi->device), NULL);
+	if (!omap_ssi->dir)
+		return -ENOMEM;
+
+	debugfs_create_file("regs", S_IRUGO, omap_ssi->dir, ssi,
+								&ssi_regs_fops);
+	/* SSI GDD (DMA) */
+	dir = debugfs_create_dir("gdd", omap_ssi->dir);
+	if (!dir)
+		goto rback;
+	debugfs_create_file("regs", S_IRUGO, dir, ssi, &ssi_gdd_regs_fops);
+
+	return 0;
+rback:
+	debugfs_remove_recursive(omap_ssi->dir);
+
+	return -ENOMEM;
+}
+
+static void ssi_debug_remove_ctrl(struct hsi_controller *ssi)
+{
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+
+	debugfs_remove_recursive(omap_ssi->dir);
+}
+#endif /* CONFIG_DEBUG_FS */
+
+/*
+ * FIXME: Horrible HACK needed until we remove the useless wakeline test
+ * in the CMT. To be removed !!!!
+ */
+void ssi_waketest(struct hsi_client *cl, unsigned int enable)
+{
+	struct hsi_port *port = hsi_get_port(cl);
+	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
+	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+
+	omap_port->wktest = !!enable;
+	if (omap_port->wktest) {
+		pm_runtime_get_sync(ssi->device.parent);
+		writel_relaxed(SSI_WAKE(0),
+				omap_ssi->sys + SSI_SET_WAKE_REG(port->num));
+	} else {
+		writel_relaxed(SSI_WAKE(0),
+				omap_ssi->sys +	SSI_CLEAR_WAKE_REG(port->num));
+		pm_runtime_put_sync(ssi->device.parent);
+	}
+}
+EXPORT_SYMBOL_GPL(ssi_waketest);
+
+static void ssi_gdd_complete(struct hsi_controller *ssi, unsigned int lch)
+{
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+	struct hsi_msg *msg = omap_ssi->gdd_trn[lch].msg;
+	struct hsi_port *port = to_hsi_port(msg->cl->device.parent);
+	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
+	unsigned int dir;
+	u32 csr;
+	u32 val;
+
+	spin_lock(&omap_ssi->lock);
+
+	val = readl(omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
+	val &= ~SSI_GDD_LCH(lch);
+	writel_relaxed(val, omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
+
+	if (msg->ttype == HSI_MSG_READ) {
+		dir = DMA_FROM_DEVICE;
+		val = SSI_DATAAVAILABLE(msg->channel);
+		pm_runtime_put_sync(ssi->device.parent);
+	} else {
+		dir = DMA_TO_DEVICE;
+		val = SSI_DATAACCEPT(msg->channel);
+		/* Keep clocks reference for write pio event */
+	}
+	dma_unmap_sg(&ssi->device, msg->sgt.sgl, msg->sgt.nents, dir);
+	csr = readw(omap_ssi->gdd + SSI_GDD_CSR_REG(lch));
+	omap_ssi->gdd_trn[lch].msg = NULL; /* release GDD lch */
+	dev_dbg(&port->device, "DMA completed ch %d ttype %d\n",
+				msg->channel, msg->ttype);
+	spin_unlock(&omap_ssi->lock);
+	if (csr & SSI_CSR_TOUR) { /* Timeout error */
+		msg->status = HSI_STATUS_ERROR;
+		msg->actual_len = 0;
+		spin_lock(&omap_port->lock);
+		list_del(&msg->link); /* Dequeue msg */
+		spin_unlock(&omap_port->lock);
+		msg->complete(msg);
+		return;
+	}
+	spin_lock(&omap_port->lock);
+	val |= readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
+	writel_relaxed(val, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
+	spin_unlock(&omap_port->lock);
+
+	msg->status = HSI_STATUS_COMPLETED;
+	msg->actual_len = sg_dma_len(msg->sgt.sgl);
+}
+
+static void ssi_gdd_tasklet(unsigned long dev)
+{
+	struct hsi_controller *ssi = (struct hsi_controller *)dev;
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+	void __iomem *sys = omap_ssi->sys;
+	unsigned int lch;
+	u32 status_reg;
+
+	pm_runtime_get_sync(ssi->device.parent);
+
+	status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
+	for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
+		if (status_reg & SSI_GDD_LCH(lch))
+			ssi_gdd_complete(ssi, lch);
+	}
+	writel_relaxed(status_reg, sys + SSI_GDD_MPU_IRQ_STATUS_REG);
+	status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
+
+	pm_runtime_put_sync(ssi->device.parent);
+
+	if (status_reg)
+		tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
+	else
+		enable_irq(omap_ssi->gdd_irq);
+
+}
+
+static irqreturn_t ssi_gdd_isr(int irq, void *ssi)
+{
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+
+	tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
+	disable_irq_nosync(irq);
+
+	return IRQ_HANDLED;
+}
+
+static unsigned long ssi_get_clk_rate(struct hsi_controller *ssi)
+{
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+	unsigned long rate = clk_get_rate(omap_ssi->fck);
+	return rate;
+}
+
+static int __init ssi_get_iomem(struct platform_device *pd,
+		const char *name, void __iomem **pbase, dma_addr_t *phy)
+{
+	struct resource *mem;
+	struct resource *ioarea;
+	void __iomem *base;
+	struct hsi_controller *ssi = platform_get_drvdata(pd);
+
+	mem = platform_get_resource_byname(pd, IORESOURCE_MEM, name);
+	if (!mem) {
+		dev_err(&pd->dev, "IO memory region missing (%s)\n", name);
+		return -ENXIO;
+	}
+	ioarea = devm_request_mem_region(&ssi->device, mem->start,
+					resource_size(mem), dev_name(&pd->dev));
+	if (!ioarea) {
+		dev_err(&pd->dev, "%s IO memory region request failed\n",
+								mem->name);
+		return -ENXIO;
+	}
+	base = devm_ioremap(&ssi->device, mem->start, resource_size(mem));
+	if (!base) {
+		dev_err(&pd->dev, "%s IO remap failed\n", mem->name);
+		return -ENXIO;
+	}
+	*pbase = base;
+
+	if (phy)
+		*phy = mem->start;
+
+	return 0;
+}
+
+static int __init ssi_add_controller(struct hsi_controller *ssi,
+						struct platform_device *pd)
+{
+	struct omap_ssi_controller *omap_ssi;
+	int err;
+
+	omap_ssi = devm_kzalloc(&ssi->device, sizeof(*omap_ssi), GFP_KERNEL);
+	if (!omap_ssi) {
+		dev_err(&pd->dev, "not enough memory for omap ssi\n");
+		return -ENOMEM;
+	}
+
+	ssi->id = ida_simple_get(&platform_omap_ssi_ida, 0, 0, GFP_KERNEL);
+	if (ssi->id < 0) {
+		err = ssi->id;
+		goto out_err;
+	}
+
+	ssi->owner = THIS_MODULE;
+	ssi->device.parent = &pd->dev;
+	dev_set_name(&ssi->device, "ssi%d", ssi->id);
+	hsi_controller_set_drvdata(ssi, omap_ssi);
+	omap_ssi->dev = &ssi->device;
+	err = ssi_get_iomem(pd, "sys", &omap_ssi->sys, NULL);
+	if (err < 0)
+		goto out_err;
+	err = ssi_get_iomem(pd, "gdd", &omap_ssi->gdd, NULL);
+	if (err < 0)
+		goto out_err;
+	err = platform_get_irq_byname(pd, "gdd_mpu");
+	if (err < 0) {
+		dev_err(&pd->dev, "GDD IRQ resource missing\n");
+		goto out_err;
+	}
+	omap_ssi->gdd_irq = err;
+	tasklet_init(&omap_ssi->gdd_tasklet, ssi_gdd_tasklet,
+							(unsigned long)ssi);
+	err = devm_request_irq(&ssi->device, omap_ssi->gdd_irq, ssi_gdd_isr,
+						0, "gdd_mpu", ssi);
+	if (err < 0) {
+		dev_err(&ssi->device, "Request GDD IRQ %d failed (%d)",
+							omap_ssi->gdd_irq, err);
+		goto out_err;
+	}
+
+	omap_ssi->port = devm_kzalloc(&ssi->device,
+		sizeof(struct omap_ssi_port *) * ssi->num_ports, GFP_KERNEL);
+	if (!omap_ssi->port) {
+		err = -ENOMEM;
+		goto out_err;
+	}
+
+	omap_ssi->fck = devm_clk_get(&ssi->device, "ssi_ssr_fck");
+	if (IS_ERR(omap_ssi->fck)) {
+		dev_err(&pd->dev, "Could not acquire clock \"ssi_ssr_fck\": %li\n",
+			PTR_ERR(omap_ssi->fck));
+		err = -ENODEV;
+		goto out_err;
+	}
+
+	/* TODO: find register, which can be used to detect context loss */
+	omap_ssi->get_loss = NULL;
+
+	omap_ssi->max_speed = UINT_MAX;
+	spin_lock_init(&omap_ssi->lock);
+	err = hsi_register_controller(ssi);
+
+	if (err < 0)
+		goto out_err;
+
+	return 0;
+
+out_err:
+	ida_simple_remove(&platform_omap_ssi_ida, ssi->id);
+	return err;
+}
+
+static int __init ssi_hw_init(struct hsi_controller *ssi)
+{
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+	unsigned int i;
+	u32 val;
+	int err;
+
+	err = pm_runtime_get_sync(ssi->device.parent);
+	if (err < 0) {
+		dev_err(&ssi->device, "runtime PM failed %d\n", err);
+		return err;
+	}
+	/* Reseting SSI controller */
+	writel_relaxed(SSI_SOFTRESET, omap_ssi->sys + SSI_SYSCONFIG_REG);
+	val = readl(omap_ssi->sys + SSI_SYSSTATUS_REG);
+	for (i = 0; ((i < 20) && !(val & SSI_RESETDONE)); i++) {
+		msleep(20);
+		val = readl(omap_ssi->sys + SSI_SYSSTATUS_REG);
+	}
+	if (!(val & SSI_RESETDONE)) {
+		dev_err(&ssi->device, "SSI HW reset failed\n");
+		pm_runtime_put_sync(ssi->device.parent);
+		return -EIO;
+	}
+	/* Reseting GDD */
+	writel_relaxed(SSI_SWRESET, omap_ssi->gdd + SSI_GDD_GRST_REG);
+	/* Get FCK rate in KHz */
+	omap_ssi->fck_rate = DIV_ROUND_CLOSEST(ssi_get_clk_rate(ssi), 1000);
+	dev_dbg(&ssi->device, "SSI fck rate %lu KHz\n", omap_ssi->fck_rate);
+	/* Set default PM settings */
+	val = SSI_AUTOIDLE | SSI_SIDLEMODE_SMART | SSI_MIDLEMODE_SMART;
+	writel_relaxed(val, omap_ssi->sys + SSI_SYSCONFIG_REG);
+	omap_ssi->sysconfig = val;
+	writel_relaxed(SSI_CLK_AUTOGATING_ON, omap_ssi->sys + SSI_GDD_GCR_REG);
+	omap_ssi->gdd_gcr = SSI_CLK_AUTOGATING_ON;
+	pm_runtime_put_sync(ssi->device.parent);
+
+	return 0;
+}
+
+static void ssi_remove_controller(struct hsi_controller *ssi)
+{
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+	int id = ssi->id;
+	tasklet_kill(&omap_ssi->gdd_tasklet);
+	hsi_unregister_controller(ssi);
+	ida_simple_remove(&platform_omap_ssi_ida, id);
+}
+
+static inline int ssi_of_get_available_ports_count(const struct device_node *np)
+{
+	struct device_node *child;
+	int num = 0;
+
+	for_each_available_child_of_node(np, child)
+		if (of_device_is_compatible(child, "ti,omap3-ssi-port"))
+			num++;
+
+	return num;
+}
+
+static int ssi_remove_ports(struct device *dev, void *c)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+
+	of_device_unregister(pdev);
+
+	return 0;
+}
+
+static int __init ssi_probe(struct platform_device *pd)
+{
+	struct platform_device *childpdev;
+	struct device_node *np = pd->dev.of_node;
+	struct device_node *child;
+	struct hsi_controller *ssi;
+	int err;
+	int num_ports;
+
+	if (!np) {
+		dev_err(&pd->dev, "missing device tree data\n");
+		return -EINVAL;
+	}
+
+	num_ports = ssi_of_get_available_ports_count(np);
+
+	ssi = hsi_alloc_controller(num_ports, GFP_KERNEL);
+	if (!ssi) {
+		dev_err(&pd->dev, "No memory for controller\n");
+		return -ENOMEM;
+	}
+
+	platform_set_drvdata(pd, ssi);
+
+	err = ssi_add_controller(ssi, pd);
+	if (err < 0)
+		goto out1;
+
+	pm_runtime_irq_safe(&pd->dev);
+	pm_runtime_enable(&pd->dev);
+
+	err = ssi_hw_init(ssi);
+	if (err < 0)
+		goto out2;
+#ifdef CONFIG_DEBUG_FS
+	err = ssi_debug_add_ctrl(ssi);
+	if (err < 0)
+		goto out2;
+#endif
+
+	for_each_available_child_of_node(np, child) {
+		if (!of_device_is_compatible(child, "ti,omap3-ssi-port"))
+			continue;
+
+		childpdev = of_platform_device_create(child, NULL, &pd->dev);
+		if (!childpdev) {
+			err = -ENODEV;
+			dev_err(&pd->dev, "failed to create ssi controller port\n");
+			goto out3;
+		}
+	}
+
+	dev_info(&pd->dev, "ssi controller %d initialized (%d ports)!\n",
+		ssi->id, num_ports);
+	return err;
+out3:
+	device_for_each_child(&pd->dev, NULL, ssi_remove_ports);
+out2:
+	ssi_remove_controller(ssi);
+out1:
+	platform_set_drvdata(pd, NULL);
+	pm_runtime_disable(&pd->dev);
+
+	return err;
+}
+
+static int __exit ssi_remove(struct platform_device *pd)
+{
+	struct hsi_controller *ssi = platform_get_drvdata(pd);
+
+#ifdef CONFIG_DEBUG_FS
+	ssi_debug_remove_ctrl(ssi);
+#endif
+	ssi_remove_controller(ssi);
+	platform_set_drvdata(pd, NULL);
+
+	pm_runtime_disable(&pd->dev);
+
+	/* cleanup of of_platform_populate() call */
+	device_for_each_child(&pd->dev, NULL, ssi_remove_ports);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_RUNTIME
+static int omap_ssi_runtime_suspend(struct device *dev)
+{
+	struct hsi_controller *ssi = dev_get_drvdata(dev);
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+
+	dev_dbg(dev, "runtime suspend!\n");
+
+	if (omap_ssi->get_loss)
+		omap_ssi->loss_count =
+				omap_ssi->get_loss(ssi->device.parent);
+
+	return 0;
+}
+
+static int omap_ssi_runtime_resume(struct device *dev)
+{
+	struct hsi_controller *ssi = dev_get_drvdata(dev);
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+
+	dev_dbg(dev, "runtime resume!\n");
+
+	if ((omap_ssi->get_loss) && (omap_ssi->loss_count ==
+				omap_ssi->get_loss(ssi->device.parent)))
+		return 0;
+
+	writel_relaxed(omap_ssi->gdd_gcr, omap_ssi->gdd + SSI_GDD_GCR_REG);
+
+	return 0;
+}
+
+static const struct dev_pm_ops omap_ssi_pm_ops = {
+	SET_RUNTIME_PM_OPS(omap_ssi_runtime_suspend, omap_ssi_runtime_resume,
+		NULL)
+};
+
+#define DEV_PM_OPS     (&omap_ssi_pm_ops)
+#else
+#define DEV_PM_OPS     NULL
+#endif
+
+#ifdef CONFIG_OF
+static const struct of_device_id omap_ssi_of_match[] = {
+	{ .compatible = "ti,omap3-ssi", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, omap_ssi_of_match);
+#else
+#define omap_ssi_of_match NULL
+#endif
+
+static struct platform_driver ssi_pdriver = {
+	.remove	= __exit_p(ssi_remove),
+	.driver	= {
+		.name	= "omap_ssi",
+		.owner	= THIS_MODULE,
+		.pm     = DEV_PM_OPS,
+		.of_match_table = omap_ssi_of_match,
+	},
+};
+
+module_platform_driver_probe(ssi_pdriver, ssi_probe);
+
+MODULE_ALIAS("platform:omap_ssi");
+MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>");
+MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
+MODULE_DESCRIPTION("Synchronous Serial Interface Driver");
+MODULE_LICENSE("GPL v2");

drivers/hsi/controllers/omap_ssi.h

@@ -0,0 +1,166 @@
+/* OMAP SSI internal interface.
+ *
+ * Copyright (C) 2010 Nokia Corporation. All rights reserved.
+ * Copyright (C) 2013 Sebastian Reichel
+ *
+ * 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_OMAP_SSI_H__
+#define __LINUX_HSI_OMAP_SSI_H__
+
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/hsi/hsi.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+
+#define SSI_MAX_CHANNELS	8
+#define SSI_MAX_GDD_LCH		8
+#define SSI_BYTES_TO_FRAMES(x) ((((x) - 1) >> 2) + 1)
+
+/**
+ * struct omap_ssm_ctx - OMAP synchronous serial module (TX/RX) context
+ * @mode: Bit transmission mode
+ * @channels: Number of channels
+ * @framesize: Frame size in bits
+ * @timeout: RX frame timeout
+ * @divisor: TX divider
+ * @arb_mode: Arbitration mode for TX frame (Round robin, priority)
+ */
+struct omap_ssm_ctx {
+	u32	mode;
+	u32	channels;
+	u32	frame_size;
+	union	{
+			u32	timeout; /* Rx Only */
+			struct	{
+					u32	arb_mode;
+					u32	divisor;
+			}; /* Tx only */
+	};
+};
+
+/**
+ * struct omap_ssi_port - OMAP SSI port data
+ * @dev: device associated to the port (HSI port)
+ * @pdev: platform device associated to the port
+ * @sst_dma: SSI transmitter physical base address
+ * @ssr_dma: SSI receiver physical base address
+ * @sst_base: SSI transmitter base address
+ * @ssr_base: SSI receiver base address
+ * @wk_lock: spin lock to serialize access to the wake lines
+ * @lock: Spin lock to serialize access to the SSI port
+ * @channels: Current number of channels configured (1,2,4 or 8)
+ * @txqueue: TX message queues
+ * @rxqueue: RX message queues
+ * @brkqueue: Queue of incoming HWBREAK requests (FRAME mode)
+ * @irq: IRQ number
+ * @wake_irq: IRQ number for incoming wake line (-1 if none)
+ * @wake_gpio: GPIO number for incoming wake line (-1 if none)
+ * @pio_tasklet: Bottom half for PIO transfers and events
+ * @wake_tasklet: Bottom half for incoming wake events
+ * @wkin_cken: Keep track of clock references due to the incoming wake line
+ * @wk_refcount: Reference count for output wake line
+ * @sys_mpu_enable: Context for the interrupt enable register for irq 0
+ * @sst: Context for the synchronous serial transmitter
+ * @ssr: Context for the synchronous serial receiver
+ */
+struct omap_ssi_port {
+	struct device		*dev;
+	struct device           *pdev;
+	dma_addr_t		sst_dma;
+	dma_addr_t		ssr_dma;
+	void __iomem		*sst_base;
+	void __iomem		*ssr_base;
+	spinlock_t		wk_lock;
+	spinlock_t		lock;
+	unsigned int		channels;
+	struct list_head	txqueue[SSI_MAX_CHANNELS];
+	struct list_head	rxqueue[SSI_MAX_CHANNELS];
+	struct list_head	brkqueue;
+	unsigned int		irq;
+	int			wake_irq;
+	int			wake_gpio;
+	struct tasklet_struct	pio_tasklet;
+	struct tasklet_struct	wake_tasklet;
+	bool			wktest:1; /* FIXME: HACK to be removed */
+	bool			wkin_cken:1; /* Workaround */
+	unsigned int		wk_refcount;
+	/* OMAP SSI port context */
+	u32			sys_mpu_enable; /* We use only one irq */
+	struct omap_ssm_ctx	sst;
+	struct omap_ssm_ctx	ssr;
+	u32			loss_count;
+	u32			port_id;
+#ifdef CONFIG_DEBUG_FS
+	struct dentry *dir;
+#endif
+};
+
+/**
+ * struct gdd_trn - GDD transaction data
+ * @msg: Pointer to the HSI message being served
+ * @sg: Pointer to the current sg entry being served
+ */
+struct gdd_trn {
+	struct hsi_msg		*msg;
+	struct scatterlist	*sg;
+};
+
+/**
+ * struct omap_ssi_controller - OMAP SSI controller data
+ * @dev: device associated to the controller (HSI controller)
+ * @sys: SSI I/O base address
+ * @gdd: GDD I/O base address
+ * @fck: SSI functional clock
+ * @gdd_irq: IRQ line for GDD
+ * @gdd_tasklet: bottom half for DMA transfers
+ * @gdd_trn: Array of GDD transaction data for ongoing GDD transfers
+ * @lock: lock to serialize access to GDD
+ * @loss_count: To follow if we need to restore context or not
+ * @max_speed: Maximum TX speed (Kb/s) set by the clients.
+ * @sysconfig: SSI controller saved context
+ * @gdd_gcr: SSI GDD saved context
+ * @get_loss: Pointer to omap_pm_get_dev_context_loss_count, if any
+ * @port: Array of pointers of the ports of the controller
+ * @dir: Debugfs SSI root directory
+ */
+struct omap_ssi_controller {
+	struct device		*dev;
+	void __iomem		*sys;
+	void __iomem		*gdd;
+	struct clk		*fck;
+	unsigned int		gdd_irq;
+	struct tasklet_struct	gdd_tasklet;
+	struct gdd_trn		gdd_trn[SSI_MAX_GDD_LCH];
+	spinlock_t		lock;
+	unsigned long		fck_rate;
+	u32			loss_count;
+	u32			max_speed;
+	/* OMAP SSI Controller context */
+	u32			sysconfig;
+	u32			gdd_gcr;
+	int			(*get_loss)(struct device *dev);
+	struct omap_ssi_port	**port;
+#ifdef CONFIG_DEBUG_FS
+	struct dentry *dir;
+#endif
+};
+
+#endif /* __LINUX_HSI_OMAP_SSI_H__ */

drivers/hsi/controllers/omap_ssi_regs.h

@@ -0,0 +1,171 @@
+/* Hardware definitions for SSI.
+ *
+ * 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 __OMAP_SSI_REGS_H__
+#define __OMAP_SSI_REGS_H__
+
+/*
+ * SSI SYS registers
+ */
+#define SSI_REVISION_REG    0
+#  define SSI_REV_MAJOR    0xf0
+#  define SSI_REV_MINOR    0xf
+#define SSI_SYSCONFIG_REG    0x10
+#  define SSI_AUTOIDLE    (1 << 0)
+#  define SSI_SOFTRESET    (1 << 1)
+#  define SSI_SIDLEMODE_FORCE  0
+#  define SSI_SIDLEMODE_NO    (1 << 3)
+#  define SSI_SIDLEMODE_SMART  (1 << 4)
+#  define SSI_SIDLEMODE_MASK  0x18
+#  define SSI_MIDLEMODE_FORCE  0
+#  define SSI_MIDLEMODE_NO    (1 << 12)
+#  define SSI_MIDLEMODE_SMART  (1 << 13)
+#  define SSI_MIDLEMODE_MASK  0x3000
+#define SSI_SYSSTATUS_REG    0x14
+#  define SSI_RESETDONE    1
+#define SSI_MPU_STATUS_REG(port, irq)  (0x808 + ((port) * 0x10) + ((irq) * 2))
+#define SSI_MPU_ENABLE_REG(port, irq)  (0x80c + ((port) * 0x10) + ((irq) * 8))
+#  define SSI_DATAACCEPT(channel)    (1 << (channel))
+#  define SSI_DATAAVAILABLE(channel)  (1 << ((channel) + 8))
+#  define SSI_DATAOVERRUN(channel)    (1 << ((channel) + 16))
+#  define SSI_ERROROCCURED      (1 << 24)
+#  define SSI_BREAKDETECTED    (1 << 25)
+#define SSI_GDD_MPU_IRQ_STATUS_REG  0x0800
+#define SSI_GDD_MPU_IRQ_ENABLE_REG  0x0804
+#  define SSI_GDD_LCH(channel)  (1 << (channel))
+#define SSI_WAKE_REG(port)    (0xc00 + ((port) * 0x10))
+#define SSI_CLEAR_WAKE_REG(port)  (0xc04 + ((port) * 0x10))
+#define SSI_SET_WAKE_REG(port)    (0xc08 + ((port) * 0x10))
+#  define SSI_WAKE(channel)  (1 << (channel))
+#  define SSI_WAKE_MASK    0xff
+
+/*
+ * SSI SST registers
+ */
+#define SSI_SST_ID_REG      0
+#define SSI_SST_MODE_REG    4
+#  define SSI_MODE_VAL_MASK  3
+#  define SSI_MODE_SLEEP    0
+#  define SSI_MODE_STREAM    1
+#  define SSI_MODE_FRAME    2
+#  define SSI_MODE_MULTIPOINTS  3
+#define SSI_SST_FRAMESIZE_REG    8
+#  define SSI_FRAMESIZE_DEFAULT  31
+#define SSI_SST_TXSTATE_REG    0xc
+#  define  SSI_TXSTATE_IDLE  0
+#define SSI_SST_BUFSTATE_REG    0x10
+#  define  SSI_FULL(channel)  (1 << (channel))
+#define SSI_SST_DIVISOR_REG    0x18
+#  define SSI_MAX_DIVISOR    127
+#define SSI_SST_BREAK_REG    0x20
+#define SSI_SST_CHANNELS_REG    0x24
+#  define SSI_CHANNELS_DEFAULT  4
+#define SSI_SST_ARBMODE_REG    0x28
+#  define SSI_ARBMODE_ROUNDROBIN  0
+#  define SSI_ARBMODE_PRIORITY  1
+#define SSI_SST_BUFFER_CH_REG(channel)  (0x80 + ((channel) * 4))
+#define SSI_SST_SWAPBUF_CH_REG(channel)  (0xc0 + ((channel) * 4))
+
+/*
+ * SSI SSR registers
+ */
+#define SSI_SSR_ID_REG      0
+#define SSI_SSR_MODE_REG    4
+#define SSI_SSR_FRAMESIZE_REG    8
+#define SSI_SSR_RXSTATE_REG    0xc
+#define SSI_SSR_BUFSTATE_REG    0x10
+#  define SSI_NOTEMPTY(channel)  (1 << (channel))
+#define SSI_SSR_BREAK_REG    0x1c
+#define SSI_SSR_ERROR_REG    0x20
+#define SSI_SSR_ERRORACK_REG    0x24
+#define SSI_SSR_OVERRUN_REG    0x2c
+#define SSI_SSR_OVERRUNACK_REG    0x30
+#define SSI_SSR_TIMEOUT_REG    0x34
+#  define SSI_TIMEOUT_DEFAULT  0
+#define SSI_SSR_CHANNELS_REG    0x28
+#define SSI_SSR_BUFFER_CH_REG(channel)  (0x80 + ((channel) * 4))
+#define SSI_SSR_SWAPBUF_CH_REG(channel)  (0xc0 + ((channel) * 4))
+
+/*
+ * SSI GDD registers
+ */
+#define SSI_GDD_HW_ID_REG    0
+#define SSI_GDD_PPORT_ID_REG    0x10
+#define SSI_GDD_MPORT_ID_REG    0x14
+#define SSI_GDD_PPORT_SR_REG    0x20
+#define SSI_GDD_MPORT_SR_REG    0x24
+#  define SSI_ACTIVE_LCH_NUM_MASK  0xff
+#define SSI_GDD_TEST_REG    0x40
+#  define SSI_TEST      1
+#define SSI_GDD_GCR_REG      0x100
+#  define  SSI_CLK_AUTOGATING_ON  (1 << 3)
+#  define  SSI_FREE    (1 << 2)
+#  define  SSI_SWITCH_OFF    (1 << 0)
+#define SSI_GDD_GRST_REG    0x200
+#  define SSI_SWRESET    1
+#define SSI_GDD_CSDP_REG(channel)  (0x800 + ((channel) * 0x40))
+#  define SSI_DST_BURST_EN_MASK  0xc000
+#  define SSI_DST_SINGLE_ACCESS0  0
+#  define SSI_DST_SINGLE_ACCESS  (1 << 14)
+#  define SSI_DST_BURST_4x32_BIT  (2 << 14)
+#  define SSI_DST_BURST_8x32_BIT  (3 << 14)
+#  define SSI_DST_MASK    0x1e00
+#  define SSI_DST_MEMORY_PORT  (8 << 9)
+#  define SSI_DST_PERIPHERAL_PORT  (9 << 9)
+#  define SSI_SRC_BURST_EN_MASK  0x180
+#  define SSI_SRC_SINGLE_ACCESS0  0
+#  define SSI_SRC_SINGLE_ACCESS  (1 << 7)
+#  define SSI_SRC_BURST_4x32_BIT  (2 << 7)
+#  define SSI_SRC_BURST_8x32_BIT  (3 << 7)
+#  define SSI_SRC_MASK    0x3c
+#  define SSI_SRC_MEMORY_PORT  (8 << 2)
+#  define SSI_SRC_PERIPHERAL_PORT  (9 << 2)
+#  define SSI_DATA_TYPE_MASK  3
+#  define SSI_DATA_TYPE_S32  2
+#define SSI_GDD_CCR_REG(channel)  (0x802 + ((channel) * 0x40))
+#  define SSI_DST_AMODE_MASK  (3 << 14)
+#  define SSI_DST_AMODE_CONST  0
+#  define SSI_DST_AMODE_POSTINC  (1 << 12)
+#  define SSI_SRC_AMODE_MASK  (3 << 12)
+#  define SSI_SRC_AMODE_CONST  0
+#  define SSI_SRC_AMODE_POSTINC  (1 << 12)
+#  define SSI_CCR_ENABLE    (1 << 7)
+#  define SSI_CCR_SYNC_MASK  0x1f
+#define SSI_GDD_CICR_REG(channel)  (0x804 + ((channel) * 0x40))
+#  define SSI_BLOCK_IE    (1 << 5)
+#  define SSI_HALF_IE    (1 << 2)
+#  define SSI_TOUT_IE    (1 << 0)
+#define SSI_GDD_CSR_REG(channel)  (0x806 + ((channel) * 0x40))
+#  define SSI_CSR_SYNC    (1 << 6)
+#  define SSI_CSR_BLOCK    (1 << 5)
+#  define SSI_CSR_HALF    (1 << 2)
+#  define SSI_CSR_TOUR    (1 << 0)
+#define SSI_GDD_CSSA_REG(channel)  (0x808 + ((channel) * 0x40))
+#define SSI_GDD_CDSA_REG(channel)  (0x80c + ((channel) * 0x40))
+#define SSI_GDD_CEN_REG(channel)  (0x810 + ((channel) * 0x40))
+#define SSI_GDD_CSAC_REG(channel)  (0x818 + ((channel) * 0x40))
+#define SSI_GDD_CDAC_REG(channel)  (0x81a + ((channel) * 0x40))
+#define SSI_GDD_CLNK_CTRL_REG(channel)  (0x828 + ((channel) * 0x40))
+#  define SSI_ENABLE_LNK    (1 << 15)
+#  define SSI_STOP_LNK    (1 << 14)
+#  define SSI_NEXT_CH_ID_MASK  0xf
+
+#endif /* __OMAP_SSI_REGS_H__ */

drivers/hsi/hsi.c

@@ -0,0 +1,772 @@
+/*
+ * 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/list.h>
+#include <linux/kobject.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include "hsi_core.h"
+
+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 DEVICE_ATTR_RO(modalias);
+
+static struct attribute *hsi_bus_dev_attrs[] = {
+	&dev_attr_modalias.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(hsi_bus_dev);
+
+static int hsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	add_uevent_var(env, "MODALIAS=hsi:%s", dev_name(dev));
+
+	return 0;
+}
+
+static int hsi_bus_match(struct device *dev, struct device_driver *driver)
+{
+	if (of_driver_match_device(dev, driver))
+		return true;
+
+	if (strcmp(dev_name(dev), driver->name) == 0)
+		return true;
+
+	return false;
+}
+
+static struct bus_type hsi_bus_type = {
+	.name		= "hsi",
+	.dev_groups	= hsi_bus_dev_groups,
+	.match		= hsi_bus_match,
+	.uevent		= hsi_bus_uevent,
+};
+
+static void hsi_client_release(struct device *dev)
+{
+	struct hsi_client *cl = to_hsi_client(dev);
+
+	kfree(cl->tx_cfg.channels);
+	kfree(cl->rx_cfg.channels);
+	kfree(cl);
+}
+
+struct hsi_client *hsi_new_client(struct hsi_port *port,
+						struct hsi_board_info *info)
+{
+	struct hsi_client *cl;
+	size_t size;
+
+	cl = kzalloc(sizeof(*cl), GFP_KERNEL);
+	if (!cl)
+		return NULL;
+
+	cl->tx_cfg = info->tx_cfg;
+	if (cl->tx_cfg.channels) {
+		size = cl->tx_cfg.num_channels * sizeof(*cl->tx_cfg.channels);
+		cl->tx_cfg.channels = kzalloc(size , GFP_KERNEL);
+		memcpy(cl->tx_cfg.channels, info->tx_cfg.channels, size);
+	}
+
+	cl->rx_cfg = info->rx_cfg;
+	if (cl->rx_cfg.channels) {
+		size = cl->rx_cfg.num_channels * sizeof(*cl->rx_cfg.channels);
+		cl->rx_cfg.channels = kzalloc(size , GFP_KERNEL);
+		memcpy(cl->rx_cfg.channels, info->rx_cfg.channels, size);
+	}
+
+	cl->device.bus = &hsi_bus_type;
+	cl->device.parent = &port->device;
+	cl->device.release = hsi_client_release;
+	dev_set_name(&cl->device, "%s", info->name);
+	cl->device.platform_data = info->platform_data;
+	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);
+		put_device(&cl->device);
+	}
+
+	return cl;
+}
+EXPORT_SYMBOL_GPL(hsi_new_client);
+
+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);
+		}
+}
+
+#ifdef CONFIG_OF
+static struct hsi_board_info hsi_char_dev_info = {
+	.name = "hsi_char",
+};
+
+static int hsi_of_property_parse_mode(struct device_node *client, char *name,
+				      unsigned int *result)
+{
+	const char *mode;
+	int err;
+
+	err = of_property_read_string(client, name, &mode);
+	if (err < 0)
+		return err;
+
+	if (strcmp(mode, "stream") == 0)
+		*result = HSI_MODE_STREAM;
+	else if (strcmp(mode, "frame") == 0)
+		*result = HSI_MODE_FRAME;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static int hsi_of_property_parse_flow(struct device_node *client, char *name,
+				      unsigned int *result)
+{
+	const char *flow;
+	int err;
+
+	err = of_property_read_string(client, name, &flow);
+	if (err < 0)
+		return err;
+
+	if (strcmp(flow, "synchronized") == 0)
+		*result = HSI_FLOW_SYNC;
+	else if (strcmp(flow, "pipeline") == 0)
+		*result = HSI_FLOW_PIPE;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static int hsi_of_property_parse_arb_mode(struct device_node *client,
+					  char *name, unsigned int *result)
+{
+	const char *arb_mode;
+	int err;
+
+	err = of_property_read_string(client, name, &arb_mode);
+	if (err < 0)
+		return err;
+
+	if (strcmp(arb_mode, "round-robin") == 0)
+		*result = HSI_ARB_RR;
+	else if (strcmp(arb_mode, "priority") == 0)
+		*result = HSI_ARB_PRIO;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static void hsi_add_client_from_dt(struct hsi_port *port,
+						struct device_node *client)
+{
+	struct hsi_client *cl;
+	struct hsi_channel channel;
+	struct property *prop;
+	char name[32];
+	int length, cells, err, i, max_chan, mode;
+
+	cl = kzalloc(sizeof(*cl), GFP_KERNEL);
+	if (!cl)
+		return;
+
+	err = of_modalias_node(client, name, sizeof(name));
+	if (err)
+		goto err;
+
+	dev_set_name(&cl->device, "%s", name);
+
+	err = hsi_of_property_parse_mode(client, "hsi-mode", &mode);
+	if (err) {
+		err = hsi_of_property_parse_mode(client, "hsi-rx-mode",
+						 &cl->rx_cfg.mode);
+		if (err)
+			goto err;
+
+		err = hsi_of_property_parse_mode(client, "hsi-tx-mode",
+						 &cl->tx_cfg.mode);
+		if (err)
+			goto err;
+	} else {
+		cl->rx_cfg.mode = mode;
+		cl->tx_cfg.mode = mode;
+	}
+
+	err = of_property_read_u32(client, "hsi-speed-kbps",
+				   &cl->tx_cfg.speed);
+	if (err)
+		goto err;
+	cl->rx_cfg.speed = cl->tx_cfg.speed;
+
+	err = hsi_of_property_parse_flow(client, "hsi-flow",
+					 &cl->rx_cfg.flow);
+	if (err)
+		goto err;
+
+	err = hsi_of_property_parse_arb_mode(client, "hsi-arb-mode",
+					     &cl->rx_cfg.arb_mode);
+	if (err)
+		goto err;
+
+	prop = of_find_property(client, "hsi-channel-ids", &length);
+	if (!prop) {
+		err = -EINVAL;
+		goto err;
+	}
+
+	cells = length / sizeof(u32);
+
+	cl->rx_cfg.num_channels = cells;
+	cl->tx_cfg.num_channels = cells;
+
+	cl->rx_cfg.channels = kzalloc(cells * sizeof(channel), GFP_KERNEL);
+	if (!cl->rx_cfg.channels) {
+		err = -ENOMEM;
+		goto err;
+	}
+
+	cl->tx_cfg.channels = kzalloc(cells * sizeof(channel), GFP_KERNEL);
+	if (!cl->tx_cfg.channels) {
+		err = -ENOMEM;
+		goto err2;
+	}
+
+	max_chan = 0;
+	for (i = 0; i < cells; i++) {
+		err = of_property_read_u32_index(client, "hsi-channel-ids", i,
+						 &channel.id);
+		if (err)
+			goto err3;
+
+		err = of_property_read_string_index(client, "hsi-channel-names",
+						    i, &channel.name);
+		if (err)
+			channel.name = NULL;
+
+		if (channel.id > max_chan)
+			max_chan = channel.id;
+
+		cl->rx_cfg.channels[i] = channel;
+		cl->tx_cfg.channels[i] = channel;
+	}
+
+	cl->rx_cfg.num_hw_channels = max_chan + 1;
+	cl->tx_cfg.num_hw_channels = max_chan + 1;
+
+	cl->device.bus = &hsi_bus_type;
+	cl->device.parent = &port->device;
+	cl->device.release = hsi_client_release;
+	cl->device.of_node = client;
+
+	if (device_register(&cl->device) < 0) {
+		pr_err("hsi: failed to register client: %s\n", name);
+		put_device(&cl->device);
+		goto err3;
+	}
+
+	return;
+
+err3:
+	kfree(cl->tx_cfg.channels);
+err2:
+	kfree(cl->rx_cfg.channels);
+err:
+	kfree(cl);
+	pr_err("hsi client: missing or incorrect of property: err=%d\n", err);
+}
+
+void hsi_add_clients_from_dt(struct hsi_port *port, struct device_node *clients)
+{
+	struct device_node *child;
+
+	/* register hsi-char device */
+	hsi_new_client(port, &hsi_char_dev_info);
+
+	for_each_available_child_of_node(clients, child)
+		hsi_add_client_from_dt(port, child);
+}
+EXPORT_SYMBOL_GPL(hsi_add_clients_from_dt);
+#endif
+
+int hsi_remove_client(struct device *dev, void *data __maybe_unused)
+{
+	device_unregister(dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hsi_remove_client);
+
+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)
+{
+	struct hsi_controller *hsi = to_hsi_controller(dev);
+
+	kfree(hsi->port);
+	kfree(hsi);
+}
+
+static void hsi_port_release(struct device *dev)
+{
+	kfree(to_hsi_port(dev));
+}
+
+/**
+ * hsi_unregister_port - Unregister an HSI port
+ * @port: The HSI port to unregister
+ */
+void hsi_port_unregister_clients(struct hsi_port *port)
+{
+	device_for_each_child(&port->device, NULL, hsi_remove_client);
+}
+EXPORT_SYMBOL_GPL(hsi_port_unregister_clients);
+
+/**
+ * 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;
+
+	err = device_add(&hsi->device);
+	if (err < 0)
+		return err;
+	for (i = 0; i < hsi->num_ports; i++) {
+		hsi->port[i]->device.parent = &hsi->device;
+		err = device_add(&hsi->port[i]->device);
+		if (err < 0)
+			goto out;
+	}
+	/* Populate HSI bus with HSI clients */
+	hsi_scan_board_info(hsi);
+
+	return 0;
+out:
+	while (i-- > 0)
+		device_del(&hsi->port[i]->device);
+	device_del(&hsi->device);
+
+	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_put_controller - Free an HSI controller
+ *
+ * @hsi: Pointer to the HSI controller to freed
+ *
+ * HSI controller drivers should only use this function if they need
+ * to free their allocated hsi_controller structures before a successful
+ * call to hsi_register_controller. Other use is not allowed.
+ */
+void hsi_put_controller(struct hsi_controller *hsi)
+{
+	unsigned int i;
+
+	if (!hsi)
+		return;
+
+	for (i = 0; i < hsi->num_ports; i++)
+		if (hsi->port && hsi->port[i])
+			put_device(&hsi->port[i]->device);
+	put_device(&hsi->device);
+}
+EXPORT_SYMBOL_GPL(hsi_put_controller);
+
+/**
+ * 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;
+
+	hsi = kzalloc(sizeof(*hsi), flags);
+	if (!hsi)
+		return NULL;
+	port = kzalloc(sizeof(*port)*n_ports, flags);
+	if (!port) {
+		kfree(hsi);
+		return NULL;
+	}
+	hsi->num_ports = n_ports;
+	hsi->port = port;
+	hsi->device.release = hsi_controller_release;
+	device_initialize(&hsi->device);
+
+	for (i = 0; i < n_ports; i++) {
+		port[i] = kzalloc(sizeof(**port), flags);
+		if (port[i] == NULL)
+			goto out;
+		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);
+		ATOMIC_INIT_NOTIFIER_HEAD(&port[i]->n_head);
+		dev_set_name(&port[i]->device, "port%d", i);
+		hsi->port[i]->device.release = hsi_port_release;
+		device_initialize(&hsi->port[i]->device);
+	}
+
+	return hsi;
+out:
+	hsi_put_controller(hsi);
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(hsi_alloc_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_event_notifier_call(struct notifier_block *nb,
+				unsigned long event, void *data __maybe_unused)
+{
+	struct hsi_client *cl = container_of(nb, struct hsi_client, nb);
+
+	(*cl->ehandler)(cl, event);
+
+	return 0;
+}
+
+/**
+ * hsi_register_port_event - Register a client to receive port events
+ * @cl: HSI client that wants to receive port events
+ * @handler: Event handler callback
+ *
+ * Clients should register a callback to be able to receive
+ * events from the ports. Registration should happen after
+ * claiming the port.
+ * The handler can be called in interrupt context.
+ *
+ * Returns -errno on error, or 0 on success.
+ */
+int hsi_register_port_event(struct hsi_client *cl,
+			void (*handler)(struct hsi_client *, unsigned long))
+{
+	struct hsi_port *port = hsi_get_port(cl);
+
+	if (!handler || cl->ehandler)
+		return -EINVAL;
+	if (!hsi_port_claimed(cl))
+		return -EACCES;
+	cl->ehandler = handler;
+	cl->nb.notifier_call = hsi_event_notifier_call;
+
+	return atomic_notifier_chain_register(&port->n_head, &cl->nb);
+}
+EXPORT_SYMBOL_GPL(hsi_register_port_event);
+
+/**
+ * hsi_unregister_port_event - Stop receiving port events for a client
+ * @cl: HSI client that wants to stop receiving port events
+ *
+ * Clients should call this function before releasing their associated
+ * port.
+ *
+ * Returns -errno on error, or 0 on success.
+ */
+int hsi_unregister_port_event(struct hsi_client *cl)
+{
+	struct hsi_port *port = hsi_get_port(cl);
+	int err;
+
+	WARN_ON(!hsi_port_claimed(cl));
+
+	err = atomic_notifier_chain_unregister(&port->n_head, &cl->nb);
+	if (!err)
+		cl->ehandler = NULL;
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(hsi_unregister_port_event);
+
+/**
+ * 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
+ *
+ * Returns -errno on error, or 0 on success.
+ */
+int hsi_event(struct hsi_port *port, unsigned long event)
+{
+	return atomic_notifier_call_chain(&port->n_head, event, NULL);
+}
+EXPORT_SYMBOL_GPL(hsi_event);
+
+/**
+ * hsi_get_channel_id_by_name - acquire channel id by channel name
+ * @cl: HSI client, which uses the channel
+ * @name: name the channel is known under
+ *
+ * Clients can call this function to get the hsi channel ids similar to
+ * requesting IRQs or GPIOs by name. This function assumes the same
+ * channel configuration is used for RX and TX.
+ *
+ * Returns -errno on error or channel id on success.
+ */
+int hsi_get_channel_id_by_name(struct hsi_client *cl, char *name)
+{
+	int i;
+
+	if (!cl->rx_cfg.channels)
+		return -ENOENT;
+
+	for (i = 0; i < cl->rx_cfg.num_channels; i++)
+		if (!strcmp(cl->rx_cfg.channels[i].name, name))
+			return cl->rx_cfg.channels[i].id;
+
+	return -ENXIO;
+}
+EXPORT_SYMBOL_GPL(hsi_get_channel_id_by_name);
+
+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");

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;
+}

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__ */