HID: intel-ish-hid: ISH HID client driver

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.

Original-author: Daniel Drubin <daniel.drubin@intel.com>
Reviewed-and-tested-by: Ooi, Joyce <joyce.ooi@intel.com>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Rann Bar-On <rb6@duke.edu>
Tested-by: Atri Bhattacharya <badshah400@aim.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 978 insertions, 0 deletions

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 000000000000..5c643d7a07b2
--- /dev/null
+++ b/drivers/hid/intel-ish-hid/ishtp-hid-client.c
@@ -0,0 +1,978 @@
+/*
+ * 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 <linux/sched.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(&client_data->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;
+	int curr_hid_dev = client_data->cur_hid_dev;
+
+	if (data_len < sizeof(struct hostif_msg_hdr)) {
+		dev_err(&client_data->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;
+		}
+
+		hid_ishtp_trace(client_data,  "%s %d\n",
+				__func__, recv_msg->hdr.command & CMD_MASK);
+
+		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;
+			if (!client_data->hid_devices)
+				client_data->hid_devices = devm_kzalloc(
+						&client_data->cl_device->dev,
+						client_data->hid_dev_count *
+						sizeof(struct device_info),
+						GFP_KERNEL);
+			if (!client_data->hid_devices) {
+				dev_err(&client_data->cl_device->dev,
+				"Mem alloc failed for hid device info\n");
+				wake_up_interruptible(&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(&client_data->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 = true;
+			wake_up_interruptible(&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;
+			}
+			if (!client_data->hid_descr[curr_hid_dev])
+				client_data->hid_descr[curr_hid_dev] =
+				devm_kmalloc(&client_data->cl_device->dev,
+					     payload_len, GFP_KERNEL);
+			if (client_data->hid_descr[curr_hid_dev]) {
+				memcpy(client_data->hid_descr[curr_hid_dev],
+				       payload, payload_len);
+				client_data->hid_descr_size[curr_hid_dev] =
+					payload_len;
+				client_data->hid_descr_done = true;
+			}
+			wake_up_interruptible(&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;
+			}
+			if (!client_data->report_descr[curr_hid_dev])
+				client_data->report_descr[curr_hid_dev] =
+				devm_kmalloc(&client_data->cl_device->dev,
+					     payload_len, GFP_KERNEL);
+			if (client_data->report_descr[curr_hid_dev])  {
+				memcpy(client_data->report_descr[curr_hid_dev],
+				       payload,
+				       payload_len);
+				client_data->report_descr_size[curr_hid_dev] =
+					payload_len;
+				client_data->report_descr_done = true;
+			}
+			wake_up_interruptible(&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);
+						ishtp_hid_wakeup(
+						client_data->hid_sensor_hubs[
+							i]);
+						break;
+					}
+			}
+			break;
+
+		case HOSTIF_SET_FEATURE_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]) {
+						ishtp_hid_wakeup(
+						client_data->hid_sensor_hubs[
+							i]);
+						break;
+					}
+			}
+			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_cl_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_hid_data *hid_data =  hid->driver_data;
+	struct ishtp_cl_data *client_data = hid_data->client_data;
+	struct hostif_msg *msg = (struct hostif_msg *)buf;
+	int	rv;
+	int	i;
+
+	hid_ishtp_trace(client_data,  "%s hid %p\n", __func__, hid);
+
+	rv = ishtp_hid_link_ready_wait(client_data);
+	if (rv) {
+		hid_ishtp_trace(client_data,  "%s hid %p link not ready\n",
+				__func__, hid);
+		return;
+	}
+
+	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(client_data->hid_ishtp_cl, buf, len);
+	if (rv)
+		hid_ishtp_trace(client_data,  "%s hid %p send failed\n",
+				__func__, hid);
+}
+
+/**
+ * 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_hid_data *hid_data =  hid->driver_data;
+	struct ishtp_cl_data *client_data = hid_data->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;
+
+	hid_ishtp_trace(client_data,  "%s hid %p\n", __func__, hid);
+	rv = ishtp_hid_link_ready_wait(client_data);
+	if (rv) {
+		hid_ishtp_trace(client_data,  "%s hid %p link not ready\n",
+				__func__, hid);
+		return;
+	}
+
+	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(client_data->hid_ishtp_cl, buf, len);
+	if (rv)
+		hid_ishtp_trace(client_data,  "%s hid %p send failed\n",
+				__func__, hid);
+}
+
+/**
+ * ishtp_hid_link_ready_wait() - Wait for link ready
+ * @client_data:	client data instance
+ *
+ * If the transport link started suspend process, then wait, till either
+ * resumed or timeout
+ *
+ * Return: 0 on success, non zero on error
+ */
+int ishtp_hid_link_ready_wait(struct ishtp_cl_data *client_data)
+{
+	int rc;
+
+	if (client_data->suspended) {
+		hid_ishtp_trace(client_data,  "wait for link ready\n");
+		rc = wait_event_interruptible_timeout(
+					client_data->ishtp_resume_wait,
+					!client_data->suspended,
+					5 * HZ);
+
+		if (rc == 0) {
+			hid_ishtp_trace(client_data,  "link not ready\n");
+			return -EIO;
+		}
+		hid_ishtp_trace(client_data,  "link ready\n");
+	}
+
+	return 0;
+}
+
+/**
+ * ishtp_enum_enum_devices() - Enumerate hid devices
+ * @hid_ishtp_cl:	client instance
+ *
+ * Helper function to send request to firmware to enumerate HID devices
+ *
+ * Return: 0 on success, non zero on error
+ */
+static int ishtp_enum_enum_devices(struct ishtp_cl *hid_ishtp_cl)
+{
+	struct hostif_msg msg;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+	int retry_count;
+	int rv;
+
+	/* Send HOSTIF_DM_ENUM_DEVICES */
+	memset(&msg, 0, sizeof(struct hostif_msg));
+	msg.hdr.command = HOSTIF_DM_ENUM_DEVICES;
+	rv = ishtp_cl_send(hid_ishtp_cl, (unsigned char *)&msg,
+			   sizeof(struct hostif_msg));
+	if (rv)
+		return rv;
+
+	retry_count = 0;
+	while (!client_data->enum_devices_done &&
+	       retry_count < 10) {
+		wait_event_interruptible_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,
+					   (unsigned char *) &msg,
+					   sizeof(struct hostif_msg));
+	}
+	if (!client_data->enum_devices_done) {
+		dev_err(&client_data->cl_device->dev,
+			"[hid-ish]: timed out waiting for enum_devices\n");
+		return -ETIMEDOUT;
+	}
+	if (!client_data->hid_devices) {
+		dev_err(&client_data->cl_device->dev,
+			"[hid-ish]: failed to allocate HID dev structures\n");
+		return -ENOMEM;
+	}
+
+	client_data->num_hid_devices = client_data->hid_dev_count;
+	dev_info(&hid_ishtp_cl->device->dev,
+		"[hid-ish]: enum_devices_done OK, num_hid_devices=%d\n",
+		client_data->num_hid_devices);
+
+	return	0;
+}
+
+/**
+ * ishtp_get_hid_descriptor() - Get hid descriptor
+ * @hid_ishtp_cl:	client instance
+ * @index:		Index into the hid_descr array
+ *
+ * Helper function to send request to firmware get HID descriptor of a device
+ *
+ * Return: 0 on success, non zero on error
+ */
+static int ishtp_get_hid_descriptor(struct ishtp_cl *hid_ishtp_cl, int index)
+{
+	struct hostif_msg msg;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+	int rv;
+
+	/* Get HID descriptor */
+	client_data->hid_descr_done = false;
+	memset(&msg, 0, sizeof(struct hostif_msg));
+	msg.hdr.command = HOSTIF_GET_HID_DESCRIPTOR;
+	msg.hdr.device_id = client_data->hid_devices[index].dev_id;
+	rv = ishtp_cl_send(hid_ishtp_cl, (unsigned char *) &msg,
+			   sizeof(struct hostif_msg));
+	if (rv)
+		return rv;
+
+	if (!client_data->hid_descr_done) {
+		wait_event_interruptible_timeout(client_data->init_wait,
+						 client_data->hid_descr_done,
+						 3 * HZ);
+		if (!client_data->hid_descr_done) {
+			dev_err(&client_data->cl_device->dev,
+				"[hid-ish]: timed out for hid_descr_done\n");
+			return -EIO;
+		}
+
+		if (!client_data->hid_descr[index]) {
+			dev_err(&client_data->cl_device->dev,
+				"[hid-ish]: allocation HID desc fail\n");
+			return -ENOMEM;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * ishtp_get_report_descriptor() - Get report descriptor
+ * @hid_ishtp_cl:	client instance
+ * @index:		Index into the hid_descr array
+ *
+ * Helper function to send request to firmware get HID report descriptor of
+ * a device
+ *
+ * Return: 0 on success, non zero on error
+ */
+static int ishtp_get_report_descriptor(struct ishtp_cl *hid_ishtp_cl,
+				       int index)
+{
+	struct hostif_msg msg;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+	int rv;
+
+	/* Get report descriptor */
+	client_data->report_descr_done = false;
+	memset(&msg, 0, sizeof(struct hostif_msg));
+	msg.hdr.command = HOSTIF_GET_REPORT_DESCRIPTOR;
+	msg.hdr.device_id = client_data->hid_devices[index].dev_id;
+	rv = ishtp_cl_send(hid_ishtp_cl, (unsigned char *) &msg,
+			   sizeof(struct hostif_msg));
+	if (rv)
+		return rv;
+
+	if (!client_data->report_descr_done)
+		wait_event_interruptible_timeout(client_data->init_wait,
+					 client_data->report_descr_done,
+					 3 * HZ);
+	if (!client_data->report_descr_done) {
+		dev_err(&client_data->cl_device->dev,
+				"[hid-ish]: timed out for report descr\n");
+		return -EIO;
+	}
+	if (!client_data->report_descr[index]) {
+		dev_err(&client_data->cl_device->dev,
+			"[hid-ish]: failed to alloc report descr\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+/**
+ * hid_ishtp_cl_init() - Init function for ISHTP client
+ * @hid_ishtp_cl:	ISHTP client instance
+ * @reset:		true if called for init after reset
+ *
+ * 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
+ *
+ * Return: 0 on success, non zero on error
+ */
+static int hid_ishtp_cl_init(struct ishtp_cl *hid_ishtp_cl, int reset)
+{
+	struct ishtp_device *dev;
+	unsigned long flags;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+	int i;
+	int rv;
+
+	dev_dbg(&client_data->cl_device->dev, "%s\n", __func__);
+	hid_ishtp_trace(client_data,  "%s reset flag: %d\n", __func__, reset);
+
+	rv = ishtp_cl_link(hid_ishtp_cl, ISHTP_HOST_CLIENT_ID_ANY);
+	if (rv) {
+		dev_err(&client_data->cl_device->dev,
+			"ishtp_cl_link failed\n");
+		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);
+		dev_err(&client_data->cl_device->dev,
+			"ish client uuid not found\n");
+		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) {
+		dev_err(&client_data->cl_device->dev,
+			"client connect fail\n");
+		goto err_cl_unlink;
+	}
+
+	hid_ishtp_trace(client_data,  "%s client connected\n", __func__);
+
+	/* Register read callback */
+	ishtp_register_event_cb(hid_ishtp_cl->device, ish_cl_event_cb);
+
+	rv = ishtp_enum_enum_devices(hid_ishtp_cl);
+	if (rv)
+		goto err_cl_disconnect;
+
+	hid_ishtp_trace(client_data,  "%s enumerated device count %d\n",
+			__func__, client_data->num_hid_devices);
+
+	for (i = 0; i < client_data->num_hid_devices; ++i) {
+		client_data->cur_hid_dev = i;
+
+		rv = ishtp_get_hid_descriptor(hid_ishtp_cl, i);
+		if (rv)
+			goto err_cl_disconnect;
+
+		rv = ishtp_get_report_descriptor(hid_ishtp_cl, i);
+		if (rv)
+			goto err_cl_disconnect;
+
+		if (!reset) {
+			rv = ishtp_hid_probe(i, client_data);
+			if (rv) {
+				dev_err(&client_data->cl_device->dev,
+				"[hid-ish]: HID probe for #%u failed: %d\n",
+				i, rv);
+				goto err_cl_disconnect;
+			}
+		}
+	} /* for() on all hid devices */
+
+	client_data->init_done = 1;
+	client_data->suspended = false;
+	wake_up_interruptible(&client_data->ishtp_resume_wait);
+	hid_ishtp_trace(client_data,  "%s successful init\n", __func__);
+	return 0;
+
+err_cl_disconnect:
+	hid_ishtp_cl->state = ISHTP_CL_DISCONNECTING;
+	ishtp_cl_disconnect(hid_ishtp_cl);
+err_cl_unlink:
+	ishtp_cl_unlink(hid_ishtp_cl);
+	return rv;
+}
+
+/**
+ * hid_ishtp_cl_deinit() - Deinit function for ISHTP client
+ * @hid_ishtp_cl:	ISHTP client instance
+ *
+ * Unlink and free hid client
+ */
+static void hid_ishtp_cl_deinit(struct ishtp_cl *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);
+}
+
+static void hid_ishtp_cl_reset_handler(struct work_struct *work)
+{
+	struct ishtp_cl_data *client_data;
+	struct ishtp_cl *hid_ishtp_cl;
+	struct ishtp_cl_device *cl_device;
+	int retry;
+	int rv;
+
+	client_data = container_of(work, struct ishtp_cl_data, work);
+
+	hid_ishtp_cl = client_data->hid_ishtp_cl;
+	cl_device = client_data->cl_device;
+
+	hid_ishtp_trace(client_data, "%s hid_ishtp_cl %p\n", __func__,
+			hid_ishtp_cl);
+	dev_dbg(&cl_device->dev, "%s\n", __func__);
+
+	hid_ishtp_cl_deinit(hid_ishtp_cl);
+
+	hid_ishtp_cl = ishtp_cl_allocate(cl_device->ishtp_dev);
+	if (!hid_ishtp_cl)
+		return;
+
+	cl_device->driver_data = hid_ishtp_cl;
+	hid_ishtp_cl->client_data = client_data;
+	client_data->hid_ishtp_cl = hid_ishtp_cl;
+
+	client_data->num_hid_devices = 0;
+
+	for (retry = 0; retry < 3; ++retry) {
+		rv = hid_ishtp_cl_init(hid_ishtp_cl, 1);
+		if (!rv)
+			break;
+		dev_err(&client_data->cl_device->dev, "Retry reset init\n");
+	}
+	if (rv) {
+		dev_err(&client_data->cl_device->dev, "Reset Failed\n");
+		hid_ishtp_trace(client_data, "%s Failed hid_ishtp_cl %p\n",
+				__func__, hid_ishtp_cl);
+	}
+}
+
+/**
+ * hid_ishtp_cl_probe() - ISHTP client driver probe
+ * @cl_device:		ISHTP client device instance
+ *
+ * This function gets called on device create on ISHTP bus
+ *
+ * Return: 0 on success, non zero on error
+ */
+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;
+	client_data->hid_ishtp_cl = hid_ishtp_cl;
+	client_data->cl_device = cl_device;
+
+	init_waitqueue_head(&client_data->init_wait);
+	init_waitqueue_head(&client_data->ishtp_resume_wait);
+
+	INIT_WORK(&client_data->work, hid_ishtp_cl_reset_handler);
+
+	rv = hid_ishtp_cl_init(hid_ishtp_cl, 0);
+	if (rv) {
+		ishtp_cl_free(hid_ishtp_cl);
+		return rv;
+	}
+	ishtp_get_device(cl_device);
+
+	return 0;
+}
+
+/**
+ * hid_ishtp_cl_remove() - ISHTP client driver remove
+ * @cl_device:		ISHTP client device instance
+ *
+ * This function gets called on device remove on ISHTP bus
+ *
+ * Return: 0
+ */
+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;
+
+	hid_ishtp_trace(client_data, "%s hid_ishtp_cl %p\n", __func__,
+			hid_ishtp_cl);
+
+	dev_dbg(&cl_device->dev, "%s\n", __func__);
+	hid_ishtp_cl->state = ISHTP_CL_DISCONNECTING;
+	ishtp_cl_disconnect(hid_ishtp_cl);
+	ishtp_put_device(cl_device);
+	ishtp_hid_remove(client_data);
+	hid_ishtp_cl_deinit(hid_ishtp_cl);
+
+	hid_ishtp_cl = NULL;
+
+	client_data->num_hid_devices = 0;
+
+	return 0;
+}
+
+/**
+ * hid_ishtp_cl_reset() - ISHTP client driver reset
+ * @cl_device:		ISHTP client device instance
+ *
+ * This function gets called on device reset on ISHTP bus
+ *
+ * Return: 0
+ */
+static int hid_ishtp_cl_reset(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;
+
+	hid_ishtp_trace(client_data, "%s hid_ishtp_cl %p\n", __func__,
+			hid_ishtp_cl);
+
+	schedule_work(&client_data->work);
+
+	return 0;
+}
+
+#define to_ishtp_cl_device(d) container_of(d, struct ishtp_cl_device, dev)
+
+/**
+ * hid_ishtp_cl_suspend() - ISHTP client driver suspend
+ * @device:	device instance
+ *
+ * This function gets called on system suspend
+ *
+ * Return: 0
+ */
+static int hid_ishtp_cl_suspend(struct device *device)
+{
+	struct ishtp_cl_device *cl_device = to_ishtp_cl_device(device);
+	struct ishtp_cl *hid_ishtp_cl = cl_device->driver_data;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+
+	hid_ishtp_trace(client_data, "%s hid_ishtp_cl %p\n", __func__,
+			hid_ishtp_cl);
+	client_data->suspended = true;
+
+	return 0;
+}
+
+/**
+ * hid_ishtp_cl_resume() - ISHTP client driver resume
+ * @device:	device instance
+ *
+ * This function gets called on system resume
+ *
+ * Return: 0
+ */
+static int hid_ishtp_cl_resume(struct device *device)
+{
+	struct ishtp_cl_device *cl_device = to_ishtp_cl_device(device);
+	struct ishtp_cl *hid_ishtp_cl = cl_device->driver_data;
+	struct ishtp_cl_data *client_data = hid_ishtp_cl->client_data;
+
+	hid_ishtp_trace(client_data, "%s hid_ishtp_cl %p\n", __func__,
+			hid_ishtp_cl);
+	client_data->suspended = false;
+	return 0;
+}
+
+static const struct dev_pm_ops hid_ishtp_pm_ops = {
+	.suspend = hid_ishtp_cl_suspend,
+	.resume = hid_ishtp_cl_resume,
+};
+
+static struct ishtp_cl_driver	hid_ishtp_cl_driver = {
+	.name = "ish-hid",
+	.probe = hid_ishtp_cl_probe,
+	.remove = hid_ishtp_cl_remove,
+	.reset = hid_ishtp_cl_reset,
+	.driver.pm = &hid_ishtp_pm_ops,
+};
+
+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;
+
+}
+
+static void __exit ish_hid_exit(void)
+{
+	ishtp_cl_driver_unregister(&hid_ishtp_cl_driver);
+}
+
+late_initcall(ish_hid_init);
+module_exit(ish_hid_exit);
+
+MODULE_DESCRIPTION("ISH ISHTP HID client driver");
+/* Primary author */
+MODULE_AUTHOR("Daniel Drubin <daniel.drubin@intel.com>");
+/*
+ * Several modification for multi instance support
+ * suspend/resume and clean up
+ */
+MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("ishtp:*");