[RFC 4/4] hid: intel-ish-hid: ISH HID client driver

[Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>]

From: Daniel Drubin <daniel.drubin@intel.com>

This driver is responsible for implementing ISH HID client, which
gets HID description and report. Once it has completely gets
report descriptors, it registers as a HID LL drivers. This implements
necessary callbacks so that it can be used by HID sensor hub driver.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/hid/intel-ish-hid/Makefile           |   4 +
 drivers/hid/intel-ish-hid/ishtp-hid-client.c | 672 +++++++++++++++++++++++++++
 drivers/hid/intel-ish-hid/ishtp-hid.c        | 201 ++++++++
 drivers/hid/intel-ish-hid/ishtp-hid.h        | 157 +++++++
 4 files changed, 1034 insertions(+)
 create mode 100644 drivers/hid/intel-ish-hid/ishtp-hid-client.c
 create mode 100644 drivers/hid/intel-ish-hid/ishtp-hid.c
 create mode 100644 drivers/hid/intel-ish-hid/ishtp-hid.h

diff --git a/drivers/hid/intel-ish-hid/Makefile b/drivers/hid/intel-ish-hid/Makefile
index 2c83cb9..6727c66 100644
--- a/drivers/hid/intel-ish-hid/Makefile
+++ b/drivers/hid/intel-ish-hid/Makefile
@@ -13,4 +13,8 @@ obj-$(CONFIG_INTEL_ISH_HID_IPC) += intel-ish-ipc.o
 intel-ish-ipc-objs := ipc/ipc.o
 intel-ish-ipc-objs += ipc/pci-ish.o
 
+obj-$(CONFIG_INTEL_ISH_HID) += intel-ishtp-hid.o
+intel-ishtp-hid-objs := ishtp-hid.o
+intel-ishtp-hid-objs += ishtp-hid-client.o
+
 ccflags-y += -Idrivers/hid/intel-ish-hid/ishtp
diff --git a/drivers/hid/intel-ish-hid/ishtp-hid-client.c b/drivers/hid/intel-ish-hid/ishtp-hid-client.c
new file mode 100644
index 0000000..5d22be6
--- /dev/null
+++ b/drivers/hid/intel-ish-hid/ishtp-hid-client.c
@@ -0,0 +1,672 @@
+/*
+ * ISHTP client driver for HID (ISH)
+ *
+ * Copyright (c) 2014-2016, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/hid.h>
+#include "ishtp/ishtp-dev.h"
+#include "ishtp/client.h"
+#include "ishtp-hid.h"
+
+/* Rx ring buffer pool size */
+#define HID_CL_RX_RING_SIZE	32
+#define HID_CL_TX_RING_SIZE	16
+
+/**
+ * report_bad_packets() - Report bad packets
+ * @hid_ishtp_cl:	Client instance to get stats
+ * @recv_buf:		Raw received host interface message
+ * @cur_pos:		Current position index in payload
+ * @payload_len:	Length of payload expected
+ *
+ * Dumps error in case bad packet is received
+ */
+static void report_bad_packet(struct ishtp_cl *hid_ishtp_cl, void *recv_buf,
+			      size_t cur_pos,  size_t payload_len)
+{
+	struct hostif_msg *recv_msg = recv_buf;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+
+	dev_err(&hid_ishtp_cl->device->dev, "[hid-ish]: BAD packet %02X\n"
+		"total_bad=%u cur_pos=%u\n"
+		"[%02X %02X %02X %02X]\n"
+		"payload_len=%u\n"
+		"multi_packet_cnt=%u\n"
+		"is_response=%02X\n",
+		recv_msg->hdr.command, client_data->bad_recv_cnt,
+		(unsigned int)cur_pos,
+		((unsigned char *)recv_msg)[0], ((unsigned char *)recv_msg)[1],
+		((unsigned char *)recv_msg)[2], ((unsigned char *)recv_msg)[3],
+		(unsigned int)payload_len, client_data->multi_packet_cnt,
+		recv_msg->hdr.command & ~CMD_MASK);
+}
+
+/**
+ * process_recv() - Received and parse incoming packet
+ * @hid_ishtp_cl:	Client instance to get stats
+ * @recv_buf:		Raw received host interface message
+ * @data_len:		length of the message
+ *
+ * Parse the incoming packet. If it is a response packet then it will update
+ * per instance flags and wake up the caller waiting to for the response.
+ */
+static void process_recv(struct ishtp_cl *hid_ishtp_cl, void *recv_buf,
+			 size_t data_len)
+{
+	struct hostif_msg *recv_msg;
+	unsigned char *payload;
+	struct device_info *dev_info;
+	int i, j;
+	size_t	payload_len, total_len, cur_pos;
+	int report_type;
+	struct report_list *reports_list;
+	char *reports;
+	size_t report_len;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+
+	if (data_len < sizeof(struct hostif_msg_hdr)) {
+		dev_err(&hid_ishtp_cl->device->dev,
+			"[hid-ish]: error, received %u which is "
+			"less than data header %u\n",
+			(unsigned int)data_len,
+			(unsigned int)sizeof(struct hostif_msg_hdr));
+		++client_data->bad_recv_cnt;
+		ish_hw_reset(hid_ishtp_cl->dev);
+		return;
+	}
+
+	payload = recv_buf + sizeof(struct hostif_msg_hdr);
+	total_len = data_len;
+	cur_pos = 0;
+
+	do {
+		recv_msg = (struct hostif_msg *)(recv_buf + cur_pos);
+		payload_len = recv_msg->hdr.size;
+
+		/* Sanity checks */
+		if (cur_pos + payload_len + sizeof(struct hostif_msg) >
+				total_len) {
+			++client_data->bad_recv_cnt;
+			report_bad_packet(hid_ishtp_cl, recv_msg, cur_pos,
+					  payload_len);
+			ish_hw_reset(hid_ishtp_cl->dev);
+			break;
+		}
+
+
+		switch (recv_msg->hdr.command & CMD_MASK) {
+		case HOSTIF_DM_ENUM_DEVICES:
+			if ((!(recv_msg->hdr.command & ~CMD_MASK) ||
+					client_data->init_done)) {
+				++client_data->bad_recv_cnt;
+				report_bad_packet(hid_ishtp_cl, recv_msg,
+						  cur_pos,
+						  payload_len);
+				ish_hw_reset(hid_ishtp_cl->dev);
+				break;
+			}
+			client_data->hid_dev_count = (unsigned int)*payload;
+			client_data->hid_devices = devm_kzalloc(
+						&hid_ishtp_cl->device->dev,
+						client_data->hid_dev_count *
+						sizeof(struct device_info),
+						GFP_KERNEL);
+			if (!client_data->hid_devices) {
+				dev_err(&hid_ishtp_cl->device->dev,
+				"Mem alloc failed for hid device info\n");
+				wake_up(&client_data->init_wait);
+				break;
+			}
+			for (i = 0; i < client_data->hid_dev_count; ++i) {
+				if (1 + sizeof(struct device_info) * i >=
+						payload_len) {
+					dev_err(&hid_ishtp_cl->device->dev,
+						"[hid-ish]: [ENUM_DEVICES]:"
+						" content size %lu "
+						"is bigger than "
+						"payload_len %u\n",
+						1 + sizeof(struct device_info)
+						* i,
+						(unsigned int)payload_len);
+				}
+
+				if (1 + sizeof(struct device_info) * i >=
+						data_len)
+					break;
+
+				dev_info = (struct device_info *)(payload + 1 +
+					sizeof(struct device_info) * i);
+				if (client_data->hid_devices)
+					memcpy(client_data->hid_devices + i,
+					       dev_info,
+					       sizeof(struct device_info));
+			}
+
+			client_data->enum_devices_done = 1;
+			wake_up(&client_data->init_wait);
+
+			break;
+
+		case HOSTIF_GET_HID_DESCRIPTOR:
+			if ((!(recv_msg->hdr.command & ~CMD_MASK) ||
+					client_data->init_done)) {
+				++client_data->bad_recv_cnt;
+				report_bad_packet(hid_ishtp_cl, recv_msg,
+						  cur_pos,
+						  payload_len);
+				ish_hw_reset(hid_ishtp_cl->dev);
+				break;
+			}
+			client_data->hid_descr[client_data->cur_hid_dev] =
+				devm_kmalloc(&hid_ishtp_cl->device->dev,
+					     payload_len, GFP_KERNEL);
+			if (client_data->hid_descr[client_data->cur_hid_dev]) {
+				memcpy(client_data->hid_descr[
+						client_data->cur_hid_dev],
+				       payload, payload_len);
+				client_data->hid_descr_size[
+				client_data->cur_hid_dev] = payload_len;
+				client_data->hid_descr_done = 1;
+			}
+			wake_up(&client_data->init_wait);
+
+			break;
+
+		case HOSTIF_GET_REPORT_DESCRIPTOR:
+			if ((!(recv_msg->hdr.command & ~CMD_MASK) ||
+					client_data->init_done)) {
+				++client_data->bad_recv_cnt;
+				report_bad_packet(hid_ishtp_cl, recv_msg,
+						  cur_pos,
+						  payload_len);
+				ish_hw_reset(hid_ishtp_cl->dev);
+				break;
+			}
+			client_data->report_descr[client_data->cur_hid_dev] =
+				devm_kmalloc(&hid_ishtp_cl->device->dev,
+					     payload_len, GFP_KERNEL);
+			if (client_data->report_descr[
+						client_data->cur_hid_dev]) {
+				memcpy(client_data->report_descr[
+					client_data->cur_hid_dev], payload,
+				       payload_len);
+				client_data->report_descr_size[
+				client_data->cur_hid_dev] = payload_len;
+				client_data->report_descr_done = 1;
+			}
+			wake_up(&client_data->init_wait);
+
+			break;
+
+		case HOSTIF_GET_FEATURE_REPORT:
+			report_type = HID_FEATURE_REPORT;
+			goto	do_get_report;
+
+		case HOSTIF_GET_INPUT_REPORT:
+			report_type = HID_INPUT_REPORT;
+do_get_report:
+			/* Get index of device that matches this id */
+			for (i = 0; i < client_data->num_hid_devices; ++i) {
+				if (recv_msg->hdr.device_id ==
+					client_data->hid_devices[i].dev_id)
+					if (client_data->hid_sensor_hubs[i]) {
+						hid_input_report(
+						client_data->hid_sensor_hubs[
+									i],
+						report_type, payload,
+						payload_len, 0);
+						break;
+					}
+			}
+			client_data->get_report_done = 1;
+			wake_up(&client_data->ishtp_hid_wait);
+			break;
+
+		case HOSTIF_SET_FEATURE_REPORT:
+			client_data->get_report_done = 1;
+			wake_up(&client_data->ishtp_hid_wait);
+			break;
+
+		case HOSTIF_PUBLISH_INPUT_REPORT:
+			report_type = HID_INPUT_REPORT;
+			for (i = 0; i < client_data->num_hid_devices; ++i)
+				if (recv_msg->hdr.device_id ==
+					client_data->hid_devices[i].dev_id)
+					if (client_data->hid_sensor_hubs[i])
+						hid_input_report(
+						client_data->hid_sensor_hubs[
+									i],
+						report_type, payload,
+						payload_len, 0);
+			break;
+
+		case HOSTIF_PUBLISH_INPUT_REPORT_LIST:
+			report_type = HID_INPUT_REPORT;
+			reports_list = (struct report_list *)payload;
+			reports = (char *)reports_list->reports;
+
+			for (j = 0; j < reports_list->num_of_reports; j++) {
+				recv_msg = (struct hostif_msg *)(reports +
+					sizeof(uint16_t));
+				report_len = *(uint16_t *)reports;
+				payload = reports + sizeof(uint16_t) +
+					sizeof(struct hostif_msg_hdr);
+				payload_len = report_len -
+					sizeof(struct hostif_msg_hdr);
+
+				for (i = 0; i < client_data->num_hid_devices;
+				     ++i)
+					if (recv_msg->hdr.device_id ==
+					client_data->hid_devices[i].dev_id &&
+					client_data->hid_sensor_hubs[i]) {
+						hid_input_report(
+						client_data->hid_sensor_hubs[
+									i],
+						report_type,
+						payload, payload_len,
+						0);
+					}
+
+				reports += sizeof(uint16_t) + report_len;
+			}
+			break;
+		default:
+			++client_data->bad_recv_cnt;
+			report_bad_packet(hid_ishtp_cl, recv_msg, cur_pos,
+					  payload_len);
+			ish_hw_reset(hid_ishtp_cl->dev);
+			break;
+
+		}
+
+		if (!cur_pos && cur_pos + payload_len +
+				sizeof(struct hostif_msg) < total_len)
+			++client_data->multi_packet_cnt;
+
+		cur_pos += payload_len + sizeof(struct hostif_msg);
+		payload += payload_len + sizeof(struct hostif_msg);
+
+	} while (cur_pos < total_len);
+}
+
+/**
+ * ish_cl_event_cb() - bus driver callback for incoming message/packet
+ * @device:	Pointer to the the ishtp client device for which this message
+ *		is targeted
+ *
+ * Remove the packet from the list and process the message by calling
+ * process_recv
+ */
+static void ish_cl_event_cb(struct ishtp_cl_device *device)
+{
+	struct ishtp_cl	*hid_ishtp_cl = device->driver_data;
+	struct ishtp_cl_rb *rb_in_proc;
+	size_t r_length;
+	unsigned long flags;
+
+	if (!hid_ishtp_cl)
+		return;
+
+	spin_lock_irqsave(&hid_ishtp_cl->in_process_spinlock, flags);
+	while (!list_empty(&hid_ishtp_cl->in_process_list.list)) {
+		rb_in_proc = list_entry(
+			hid_ishtp_cl->in_process_list.list.next,
+			struct ishtp_cl_rb, list);
+		list_del_init(&rb_in_proc->list);
+		spin_unlock_irqrestore(&hid_ishtp_cl->in_process_spinlock,
+			flags);
+
+		if (!rb_in_proc->buffer.data)
+			return;
+
+		r_length = rb_in_proc->buf_idx;
+
+		/* decide what to do with received data */
+		process_recv(hid_ishtp_cl, rb_in_proc->buffer.data, r_length);
+
+		ishtp_io_rb_recycle(rb_in_proc);
+		spin_lock_irqsave(&hid_ishtp_cl->in_process_spinlock, flags);
+	}
+	spin_unlock_irqrestore(&hid_ishtp_cl->in_process_spinlock, flags);
+}
+
+/**
+ * hid_ishtp_set_feature() - send request to ISH FW to set a feature request
+ * @hid:	hid device instance for this request
+ * @buf:	feature buffer
+ * @len:	Length of feature buffer
+ * @report_id:	Report id for the feature set request
+ *
+ * This is called from hid core .request() callback. This function doesn't wait
+ * for response.
+ */
+void hid_ishtp_set_feature(struct hid_device *hid, char *buf, unsigned int len,
+			   int report_id)
+{
+	struct ishtp_cl *hid_ishtp_cl = hid->driver_data;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+	struct hostif_msg *msg = (struct hostif_msg *)buf;
+	int	rv;
+	int	i;
+
+	memset(msg, 0, sizeof(struct hostif_msg));
+	msg->hdr.command = HOSTIF_SET_FEATURE_REPORT;
+	for (i = 0; i < client_data->num_hid_devices; ++i) {
+		if (hid == client_data->hid_sensor_hubs[i]) {
+			msg->hdr.device_id =
+				client_data->hid_devices[i].dev_id;
+			break;
+		}
+	}
+
+	if (i == client_data->num_hid_devices)
+		return;
+
+	rv = ishtp_cl_send(hid_ishtp_cl, buf, len);
+}
+
+/**
+ * hid_ishtp_get_report() - request to get feature/input report
+ * @hid:	hid device instance for this request
+ * @report_id:	Report id for the get request
+ * @report_type:	Report type for the this request
+ *
+ * This is called from hid core .request() callback. This function will send
+ * request to FW and return without waiting for response.
+ */
+void hid_ishtp_get_report(struct hid_device *hid, int report_id,
+			  int report_type)
+{
+	struct ishtp_cl *hid_ishtp_cl = hid->driver_data;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+	static unsigned char	buf[10];
+	unsigned int	len;
+	struct hostif_msg_to_sensor *msg = (struct hostif_msg_to_sensor *)buf;
+	int	rv;
+	int	i;
+
+	len = sizeof(struct hostif_msg_to_sensor);
+
+	memset(msg, 0, sizeof(struct hostif_msg_to_sensor));
+	msg->hdr.command = (report_type == HID_FEATURE_REPORT) ?
+		HOSTIF_GET_FEATURE_REPORT : HOSTIF_GET_INPUT_REPORT;
+	for (i = 0; i < client_data->num_hid_devices; ++i) {
+		if (hid == client_data->hid_sensor_hubs[i]) {
+			msg->hdr.device_id =
+				client_data->hid_devices[i].dev_id;
+			break;
+		}
+	}
+
+	if (i == client_data->num_hid_devices)
+		return;
+
+	msg->report_id = report_id;
+	rv = ishtp_cl_send(hid_ishtp_cl, buf, len);
+}
+
+/**
+ * hid_ishtp_cl_init() - Init function for ISHTP client
+ * @hid_istp_cl:	ISHTP client instance
+ *
+ * This function complete the initializtion of the client. The summary of
+ * processing:
+ * - Send request to enumerate the hid clients
+ *	Get the HID descriptor for each enumearated device
+ *	Get report description of each device
+ *	Register each device wik hid core by calling ishtp_hid_probe
+ */
+static int hid_ishtp_cl_init(struct ishtp_cl *hid_ishtp_cl)
+{
+	static unsigned char buf[512];
+	unsigned int len;
+	struct hostif_msg *msg = (struct hostif_msg *)buf;
+	struct ishtp_device *dev;
+	int retry_count;
+	unsigned long flags;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+	int i;
+	int rv;
+
+	init_waitqueue_head(&client_data->init_wait);
+	init_waitqueue_head(&client_data->ishtp_hid_wait);
+
+	rv = ishtp_cl_link(hid_ishtp_cl, ISHTP_HOST_CLIENT_ID_ANY);
+	if (rv)
+		return	-ENOMEM;
+
+	client_data->init_done = 0;
+
+	dev = hid_ishtp_cl->dev;
+
+	/* Connect to FW client */
+	hid_ishtp_cl->rx_ring_size = HID_CL_RX_RING_SIZE;
+	hid_ishtp_cl->tx_ring_size = HID_CL_TX_RING_SIZE;
+
+	spin_lock_irqsave(&dev->fw_clients_lock, flags);
+	i = ishtp_fw_cl_by_uuid(dev, &hid_ishtp_guid);
+	if (i < 0) {
+		spin_unlock_irqrestore(&dev->fw_clients_lock, flags);
+		return i;
+	}
+	hid_ishtp_cl->fw_client_id = dev->fw_clients[i].client_id;
+	spin_unlock_irqrestore(&dev->fw_clients_lock, flags);
+	hid_ishtp_cl->state = ISHTP_CL_CONNECTING;
+
+	rv = ishtp_cl_connect(hid_ishtp_cl);
+	if (rv)
+		goto ret;
+
+	/* Register read callback */
+	ishtp_register_event_cb(hid_ishtp_cl->device, ish_cl_event_cb);
+
+	/* Send HOSTIF_DM_ENUM_DEVICES */
+	memset(msg, 0, sizeof(struct hostif_msg));
+	msg->hdr.command = HOSTIF_DM_ENUM_DEVICES;
+	len = sizeof(struct hostif_msg);
+	rv = ishtp_cl_send(hid_ishtp_cl, buf, len);
+	if (rv)
+		goto ret;
+
+	rv = 0;
+
+	retry_count = 0;
+	while (!client_data->enum_devices_done &&
+	       retry_count < 10) {
+		wait_event_timeout(client_data->init_wait,
+				   client_data->enum_devices_done,
+				   3 * HZ);
+		++retry_count;
+		if (!client_data->enum_devices_done)
+			/* Send HOSTIF_DM_ENUM_DEVICES */
+			rv = ishtp_cl_send(hid_ishtp_cl, buf, len);
+	}
+	if (!client_data->enum_devices_done) {
+		dev_err(&hid_ishtp_cl->device->dev,
+			"[hid-ish]: timed out waiting for enum_devices\n");
+		rv = -ETIMEDOUT;
+		goto ret;
+	}
+	if (!client_data->hid_devices) {
+		dev_err(&hid_ishtp_cl->device->dev,
+			"[hid-ish]: failed to allocate HID dev structures\n");
+		rv = -ENOMEM;
+		goto ret;
+	}
+
+	client_data->num_hid_devices = client_data->hid_dev_count;
+	dev_warn(&hid_ishtp_cl->device->dev,
+		"[hid-ish]: enum_devices_done OK, num_hid_devices=%d\n",
+		client_data->num_hid_devices);
+
+	for (i = 0; i < client_data->num_hid_devices; ++i) {
+		client_data->cur_hid_dev = i;
+
+		/* Get HID descriptor */
+		client_data->hid_descr_done = 0;
+		memset(msg, 0, sizeof(struct hostif_msg));
+		msg->hdr.command = HOSTIF_GET_HID_DESCRIPTOR;
+		msg->hdr.device_id = client_data->hid_devices[i].dev_id;
+		len = sizeof(struct hostif_msg);
+		rv = ishtp_cl_send(hid_ishtp_cl, buf, len);
+		rv = 0;
+
+		if (!client_data->hid_descr_done)
+			wait_event_timeout(client_data->init_wait,
+					   client_data->hid_descr_done,
+					   30 * HZ);
+		if (!client_data->hid_descr_done) {
+			dev_err(&hid_ishtp_cl->device->dev,
+				"[hid-ish]: timed out for hid_descr_done\n");
+			continue;
+		}
+
+		if (!client_data->hid_descr[i]) {
+			dev_err(&hid_ishtp_cl->device->dev,
+				"[hid-ish]: allocation HID desc fail\n");
+			continue;
+		}
+
+		/* Get report descriptor */
+		client_data->report_descr_done = 0;
+		memset(msg, 0, sizeof(struct hostif_msg));
+		msg->hdr.command = HOSTIF_GET_REPORT_DESCRIPTOR;
+		msg->hdr.device_id = client_data->hid_devices[i].dev_id;
+		len = sizeof(struct hostif_msg);
+		rv = ishtp_cl_send(hid_ishtp_cl, buf, len);
+
+		rv = 0;
+
+		if (!client_data->report_descr_done)
+			wait_event_timeout(client_data->init_wait,
+					   client_data->report_descr_done,
+					   30 * HZ);
+		if (!client_data->report_descr_done) {
+			dev_err(&hid_ishtp_cl->device->dev,
+				"[hid-ish]: timed out for report descr\n");
+			continue;
+		}
+
+		if (!client_data->report_descr[i]) {
+			dev_err(&hid_ishtp_cl->device->dev,
+				"[hid-ish]: failed to alloc report descr\n");
+			continue;
+		}
+
+		rv = ishtp_hid_probe(i, hid_ishtp_cl);
+		if (rv) {
+			dev_err(&hid_ishtp_cl->device->dev,
+				"[hid-ish]: HID probe for #%u failed: %d\n",
+				i, rv);
+			continue;
+		}
+	} /* for() on all hid devices */
+
+ret:
+	client_data->init_done = 1;
+
+	return rv;
+}
+
+/**
+ * hid_ishtp_cl_probe() - ISHTP client driver probe
+ * @cl_device:		ISHTP client device instance
+ *
+ * This function calls on device create on ISHTP bus
+ */
+static int hid_ishtp_cl_probe(struct ishtp_cl_device *cl_device)
+{
+	struct ishtp_cl *hid_ishtp_cl;
+	struct ishtp_cl_data *client_data;
+	int rv;
+
+	if (!cl_device)
+		return	-ENODEV;
+
+	if (uuid_le_cmp(hid_ishtp_guid,
+			cl_device->fw_client->props.protocol_name) != 0)
+		return	-ENODEV;
+
+	client_data = devm_kzalloc(&cl_device->dev, sizeof(*client_data),
+				   GFP_KERNEL);
+	if (!client_data)
+		return -ENOMEM;
+
+	hid_ishtp_cl = ishtp_cl_allocate(cl_device->ishtp_dev);
+	if (!hid_ishtp_cl)
+		return -ENOMEM;
+
+	cl_device->driver_data = hid_ishtp_cl;
+	hid_ishtp_cl->client_data = client_data;
+
+	rv = hid_ishtp_cl_init(hid_ishtp_cl);
+	if (rv) {
+		ishtp_cl_free(hid_ishtp_cl);
+		return rv;
+	}
+
+	return 0;
+}
+
+/**
+ * hid_ishtp_cl_remove() - ISHTP client driver remove
+ * @cl_device:		ISHTP client device instance
+ *
+ * This function calls on device create on ISHTP bus
+ */
+static int hid_ishtp_cl_remove(struct ishtp_cl_device *cl_device)
+{
+	struct ishtp_cl *hid_ishtp_cl = cl_device->driver_data;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+
+	ishtp_hid_remove(hid_ishtp_cl);
+
+	ishtp_cl_unlink(hid_ishtp_cl);
+	ishtp_cl_flush_queues(hid_ishtp_cl);
+
+	/* disband and free all Tx and Rx client-level rings */
+	ishtp_cl_free(hid_ishtp_cl);
+	hid_ishtp_cl = NULL;
+
+	client_data->num_hid_devices = 0;
+
+	return 0;
+}
+
+
+struct ishtp_cl_driver	hid_ishtp_cl_driver = {
+	.name = "ish",
+	.probe = hid_ishtp_cl_probe,
+	.remove = hid_ishtp_cl_remove,
+};
+
+static int __init ish_hid_init(void)
+{
+	int	rv;
+
+	/* Register ISHTP client device driver with ISHTP Bus */
+	rv = ishtp_cl_driver_register(&hid_ishtp_cl_driver);
+
+	return rv;
+
+}
+late_initcall(ish_hid_init);
+
+MODULE_DESCRIPTION("ISH ISHTP HID client driver");
+/* Primary author */
+MODULE_AUTHOR("Daniel Drubin <daniel.drubin@intel.com>");
+/* Modification for multi instance support and clean up */
+MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/hid/intel-ish-hid/ishtp-hid.c b/drivers/hid/intel-ish-hid/ishtp-hid.c
new file mode 100644
index 0000000..f0c5569
--- /dev/null
+++ b/drivers/hid/intel-ish-hid/ishtp-hid.c
@@ -0,0 +1,201 @@
+/*
+ * ISHTP-HID glue driver.
+ *
+ * Copyright (c) 2012-2016, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/hid.h>
+#include "ishtp/client.h"
+#include "ishtp-hid.h"
+
+/**
+ * ishtp_hid_parse() - hid-core .parse() callback
+ * @hid:	hid device instance
+ *
+ * This function gets called during call to hid_add_device
+ */
+static int ishtp_hid_parse(struct hid_device *hid)
+{
+	struct ishtp_cl *hid_ishtp_cl = hid->driver_data;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+	int	rv;
+
+	rv = hid_parse_report(hid,
+		client_data->report_descr[client_data->cur_hid_dev],
+		client_data->report_descr_size[client_data->cur_hid_dev]);
+	if (rv)
+		return	rv;
+
+	return 0;
+}
+
+/* Empty callbacks with success return code */
+static int ishtp_hid_start(struct hid_device *hid)
+{
+	return 0;
+}
+
+static void ishtp_hid_stop(struct hid_device *hid)
+{
+}
+
+static int ishtp_hid_open(struct hid_device *hid)
+{
+	return 0;
+}
+
+static void ishtp_hid_close(struct hid_device *hid)
+{
+}
+
+static int ishtp_raw_request(struct hid_device *hdev, unsigned char reportnum,
+	__u8 *buf, size_t len, unsigned char rtype, int reqtype)
+{
+	return 0;
+}
+
+/**
+ * ishtp_hid_request() - hid-core .request() callback
+ * @hid:	hid device instance
+ * @rep:	pointer to hid_report
+ * @reqtype:	type of req. [GET|SET]_REPORT
+ *
+ * This function is used to set/get feaure/input report.
+ */
+static void ishtp_hid_request(struct hid_device *hid, struct hid_report *rep,
+	int reqtype)
+{
+	/* the specific report length, just HID part of it */
+	unsigned int len = ((rep->size - 1) >> 3) + 1 + (rep->id > 0);
+	char *buf;
+	unsigned int header_size = sizeof(struct hostif_msg);
+
+	len += header_size;
+
+	switch (reqtype) {
+	case HID_REQ_GET_REPORT:
+		hid_ishtp_get_report(hid, rep->id, rep->type);
+		break;
+	case HID_REQ_SET_REPORT:
+		/*
+		 * Spare 7 bytes for 64b accesses through
+		 * get/put_unaligned_le64()
+		 */
+		buf = kzalloc(len + 7, GFP_KERNEL);
+		if (!buf)
+			return;
+
+		hid_output_report(rep, buf + header_size);
+		hid_ishtp_set_feature(hid, buf, len, rep->id);
+		kfree(buf);
+		break;
+	}
+}
+
+/**
+ * ishtp_wait_for_response() - hid-core .wait() callback
+ * @hid:	hid device instance
+ *
+ * This function is used to wait after get feaure/input report.
+ */
+static int ishtp_wait_for_response(struct hid_device *hid)
+{
+	struct ishtp_cl *hid_ishtp_cl = hid->driver_data;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+
+	if (!client_data->get_report_done)
+		wait_event_timeout(client_data->ishtp_hid_wait,
+				   client_data->get_report_done, 3 * HZ);
+
+	if (!client_data->get_report_done) {
+		hid_err(hid,
+			"timeout waiting for response from ISHTP device\n");
+		return -1;
+	}
+
+	client_data->get_report_done = 0;
+
+	return 0;
+}
+
+static struct hid_ll_driver ishtp_hid_ll_driver = {
+	.parse = ishtp_hid_parse,
+	.start = ishtp_hid_start,
+	.stop = ishtp_hid_stop,
+	.open = ishtp_hid_open,
+	.close = ishtp_hid_close,
+	.request = ishtp_hid_request,
+	.wait = ishtp_wait_for_response,
+	.raw_request = ishtp_raw_request
+};
+
+/**
+ * ishtp_hid_probe() - hid register ll driver
+ * @curr_hid_dev:	Index of hid device calling to register
+ * @hid_ishtp_cl:	ISHTP Client instance
+ *
+ * This function is used to allocate and add HID device.
+ */
+int ishtp_hid_probe(unsigned int cur_hid_dev, struct ishtp_cl *hid_ishtp_cl)
+{
+	int rv;
+	struct hid_device	*hid;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+
+	hid = hid_allocate_device();
+	if (IS_ERR(hid)) {
+		rv = PTR_ERR(hid);
+		return	-ENOMEM;
+	}
+
+	hid->driver_data = hid_ishtp_cl;
+
+	client_data->hid_sensor_hubs[cur_hid_dev] = hid;
+
+	hid->ll_driver = &ishtp_hid_ll_driver;
+	hid->bus = BUS_ISHTP;
+	hid->version = le16_to_cpu(ISH_HID_VERSION);
+	hid->vendor = le16_to_cpu(ISH_HID_VENDOR);
+	hid->product = le16_to_cpu(ISH_HID_PRODUCT);
+
+	snprintf(hid->name, sizeof(hid->name), "%s %04hX:%04hX", "hid-ishtp",
+		hid->vendor, hid->product);
+
+	rv = hid_add_device(hid);
+	if (rv) {
+		if (rv != -ENODEV)
+			hid_err(hid, "[hid-ishtp]: can't add HID device: %d\n",
+				rv);
+		kfree(hid);
+		return	rv;
+	}
+
+	return 0;
+}
+
+/**
+ * ishtp_hid_probe() - Remove registered hid device
+ * @hid_ishtp_cl:	ISHTP Client instance
+ *
+ * This function is used to destroy allocatd HID device.
+ */
+void ishtp_hid_remove(struct ishtp_cl *hid_ishtp_cl)
+{
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+	int	i;
+
+	for (i = 0; i < client_data->num_hid_devices; ++i)
+		if (client_data->hid_sensor_hubs[i]) {
+			hid_destroy_device(client_data->hid_sensor_hubs[i]);
+			client_data->hid_sensor_hubs[i] = NULL;
+		}
+}
diff --git a/drivers/hid/intel-ish-hid/ishtp-hid.h b/drivers/hid/intel-ish-hid/ishtp-hid.h
new file mode 100644
index 0000000..9bf9198
--- /dev/null
+++ b/drivers/hid/intel-ish-hid/ishtp-hid.h
@@ -0,0 +1,157 @@
+/*
+ * ISHTP-HID glue driver's definitions.
+ *
+ * Copyright (c) 2014-2016, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+#ifndef ISHTP_HID__H
+#define	ISHTP_HID__H
+
+/* ISH Transport protocol id */
+#define	BUS_ISHTP	0x44
+
+/* The fixed ISH product and vendor id */
+#define	ISH_HID_VENDOR	0x8086
+#define	ISH_HID_PRODUCT	0x22D8
+#define	ISH_HID_VERSION	0x0200
+
+#define	CMD_MASK	0x7F
+#define	IS_RESPONSE	0x80
+
+/* ISH Transport protocol (ISHTP in short) GUID */
+static const uuid_le hid_ishtp_guid = UUID_LE(0x33AECD58, 0xB679, 0x4E54,
+					      0x9B, 0xD9, 0xA0, 0x4D, 0x34,
+					      0xF0, 0xC2, 0x26);
+
+/* ISH HID message structure */
+struct hostif_msg_hdr {
+	uint8_t	command; /* Bit 7: is_response */
+	uint8_t	device_id;
+	uint8_t	status;
+	uint8_t	flags;
+	uint16_t size;
+} __packed;
+
+struct hostif_msg {
+	struct hostif_msg_hdr	hdr;
+} __packed;
+
+struct hostif_msg_to_sensor {
+	struct hostif_msg_hdr	hdr;
+	uint8_t	report_id;
+} __packed;
+
+struct device_info {
+	uint32_t dev_id;
+	uint8_t dev_class;
+	uint16_t pid;
+	uint16_t vid;
+} __packed;
+
+struct ishtp_version {
+	uint8_t	major;
+	uint8_t	minor;
+	uint8_t	hotfix;
+	uint16_t build;
+} __packed;
+
+/* struct for ISHTP aggregated input data */
+struct report_list {
+	uint16_t total_size;
+	uint8_t	num_of_reports;
+	uint8_t	flags;
+	struct {
+		uint16_t	size_of_report;
+		uint8_t report[1];
+	} __packed reports[1];
+} __packed;
+
+/* HOSTIF commands */
+#define	HOSTIF_HID_COMMAND_BASE			0
+#define	HOSTIF_GET_HID_DESCRIPTOR		0
+#define	HOSTIF_GET_REPORT_DESCRIPTOR		1
+#define HOSTIF_GET_FEATURE_REPORT		2
+#define	HOSTIF_SET_FEATURE_REPORT		3
+#define	HOSTIF_GET_INPUT_REPORT			4
+#define	HOSTIF_PUBLISH_INPUT_REPORT		5
+#define	HOSTIF_PUBLISH_INPUT_REPORT_LIST	6
+#define	HOSTIF_DM_COMMAND_BASE			32
+#define	HOSTIF_DM_ENUM_DEVICES			33
+#define	HOSTIF_DM_ADD_DEVICE			34
+
+#define	MAX_HID_DEVICES				32
+
+/**
+ * struct ishtp_cl_data - Encapsulate per ISH TP HID Client
+ * @enum_device_done:	Enum devices response complete flag
+ * @hid_descr_done:	HID descriptor complete flag
+ * @report_descr_done:	Get report descriptor complete flag
+ * @get_report_done:	Get Feature/Input report complete flag
+ *			used during get/set request from hid core
+ * @init_done:		Init process completed successfully
+ * @num_hid_devices:	Number of HID devices enumerated in this client
+ * @cur_hid_dev:	This keeps track of the device index for which
+ *			initialization and registration with HID core
+ *			in progress.
+ * @hid_devices:	Store vid/pid/devid for each enumerated HID device
+ * @report_descr:	Stores the raw report descriptors for each HID device
+ * @report_descr_size:	Report description of size of above repo_descr[]
+ * @hid_sensor_hubs:	Pointer to hid_device for all HID device, so that
+ *			when clients are removed, they can be freed
+ * @hid_descr:		Pointer to hid descriptor for each enumerated hid
+ *			device
+ * @hid_descr_size:	Size of each above report descriptor
+ * @init_wait:		Wait queue to wait during initialization, where the
+ *			client send message to ISH FW and wait for response
+ * @ishtp_hid_wait:	The wait for get report during wait callback from hid
+ *			core
+ * @bad_recv_cnt:	Running count of packets received with error
+ * @multi_packet_cnt:	Count of fragmented packet count
+ *
+ * This structure is used to store completion flags and per client data like
+ * like report description, number of HID devices etc.
+ */
+struct ishtp_cl_data {
+	/* completion flags */
+	int enum_devices_done;
+	int hid_descr_done;
+	int report_descr_done;
+	int get_report_done;
+	int init_done;
+
+	unsigned int num_hid_devices;
+	unsigned int cur_hid_dev;
+	unsigned int hid_dev_count;
+
+	struct device_info *hid_devices;
+	unsigned char *report_descr[MAX_HID_DEVICES];
+	int report_descr_size[MAX_HID_DEVICES];
+	struct hid_device *hid_sensor_hubs[MAX_HID_DEVICES];
+	unsigned char *hid_descr[MAX_HID_DEVICES];
+	int hid_descr_size[MAX_HID_DEVICES];
+
+	wait_queue_head_t init_wait;
+	wait_queue_head_t ishtp_hid_wait;
+
+	/* Statistics */
+	unsigned int bad_recv_cnt;
+	int multi_packet_cnt;
+};
+
+/* Interface functions between HID LL driver and ISH TP client */
+void hid_ishtp_set_feature(struct hid_device *hid, char *buf, unsigned int len,
+			   int report_id);
+void hid_ishtp_get_report(struct hid_device *hid, int report_id,
+			  int report_type);
+int ishtp_hid_probe(unsigned int cur_hid_dev, struct ishtp_cl *hid_ishtp_cl);
+void ishtp_hid_remove(struct ishtp_cl *hid_ishtp_cl);
+
+#endif	/* ISHTP_HID__H */
-- 
1.9.1