[v8,3/4] SFH:Transport Driver to add support of AMD Sensor Fusion Hub (SFH)

diff --git a/drivers/hid/amd-sfh-hid/amd_sfh_client.c b/drivers/hid/amd-sfh-hid/amd_sfh_client.c
new file mode 100644
index 000000000000..3d1ccac5d99a
--- /dev/null
+++ b/drivers/hid/amd-sfh-hid/amd_sfh_client.c
@@ -0,0 +1,246 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  AMD SFH Client Layer
+ *  Copyright 2020 Advanced Micro Devices, Inc.
+ *  Authors: Nehal Bakulchandra Shah <Nehal-Bakulchandra.Shah@amd.com>
+ *	     Sandeep Singh <Sandeep.singh@amd.com>
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/hid.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/errno.h>
+
+#include "hid_descriptor/amd_sfh_hid_desc.h"
+#include "amd_sfh_pcie.h"
+#include "amd_sfh_hid.h"
+
+#define AMD_SFH_IDLE_LOOP	200
+
+struct request_list {
+	struct hid_device *hid;
+	struct list_head list;
+	u8 report_id;
+	u8 sensor_idx;
+	u8 report_type;
+	u8 current_index;
+};
+
+static struct request_list req_list;
+
+void amd_sfh_set_report(struct hid_device *hid, int report_id,
+			int report_type)
+{
+	struct amdtp_hid_data *hid_data = hid->driver_data;
+	struct amdtp_cl_data *cli_data = hid_data->cli_data;
+	int i;
+
+	for (i = 0; i < cli_data->num_hid_devices; i++) {
+		if (cli_data->hid_sensor_hubs[i] == hid) {
+			cli_data->cur_hid_dev = i;
+			break;
+		}
+	}
+	amdtp_hid_wakeup(hid);
+}
+
+int amd_sfh_get_report(struct hid_device *hid, int report_id, int report_type)
+{
+	struct amdtp_hid_data *hid_data = hid->driver_data;
+	struct amdtp_cl_data *cli_data = hid_data->cli_data;
+	int i;
+
+	for (i = 0; i < cli_data->num_hid_devices; i++) {
+		if (cli_data->hid_sensor_hubs[i] == hid) {
+			struct request_list *new = kzalloc(sizeof(*new), GFP_KERNEL);
+
+			if (!new)
+				return -ENOMEM;
+
+			new->current_index = i;
+			new->sensor_idx = cli_data->sensor_idx[i];
+			new->hid = hid;
+			new->report_type = report_type;
+			new->report_id = report_id;
+			cli_data->report_id[i] = report_id;
+			cli_data->request_done[i] = false;
+			list_add(&new->list, &req_list.list);
+			break;
+		}
+	}
+	schedule_delayed_work(&cli_data->work, 0);
+	return 0;
+}
+
+static void amd_sfh_work(struct work_struct *work)
+{
+	struct amdtp_cl_data *cli_data = container_of(work, struct amdtp_cl_data, work.work);
+	struct request_list *req_node;
+	u8 current_index, sensor_index;
+	u8 report_id, node_type;
+	u8 report_size = 0;
+
+	req_node = list_last_entry(&req_list.list, struct request_list, list);
+	list_del(&req_node->list);
+	current_index = req_node->current_index;
+	sensor_index = req_node->sensor_idx;
+	report_id = req_node->report_id;
+	node_type = req_node->report_type;
+
+	if (node_type == HID_FEATURE_REPORT) {
+		report_size = get_feature_report(sensor_index, report_id,
+						 cli_data->feature_report[current_index]);
+		if (report_size)
+			hid_input_report(cli_data->hid_sensor_hubs[current_index],
+					 cli_data->report_type[current_index],
+					 cli_data->feature_report[current_index], report_size, 0);
+		else
+			pr_err("AMDSFH: Invalid report size\n");
+
+	} else if (node_type == HID_INPUT_REPORT) {
+		report_size = get_input_report(sensor_index, report_id,
+					       cli_data->input_report[current_index],
+					       cli_data->sensor_virt_addr[current_index]);
+		if (report_size)
+			hid_input_report(cli_data->hid_sensor_hubs[current_index],
+					 cli_data->report_type[current_index],
+					 cli_data->input_report[current_index], report_size, 0);
+		else
+			pr_err("AMDSFH: Invalid report size\n");
+	}
+	cli_data->cur_hid_dev = current_index;
+	cli_data->sensor_requested_cnt[current_index] = 0;
+	amdtp_hid_wakeup(cli_data->hid_sensor_hubs[current_index]);
+}
+
+static void amd_sfh_work_buffer(struct work_struct *work)
+{
+	struct amdtp_cl_data *cli_data = container_of(work, struct amdtp_cl_data, work_buffer.work);
+	u8 report_size;
+	int i;
+
+	for (i = 0; i < cli_data->num_hid_devices; i++) {
+		report_size = get_input_report(cli_data->sensor_idx[i], cli_data->report_id[i],
+					       cli_data->input_report[i],
+					       cli_data->sensor_virt_addr[i]);
+		hid_input_report(cli_data->hid_sensor_hubs[i], HID_INPUT_REPORT,
+				 cli_data->input_report[i], report_size, 0);
+	}
+	schedule_delayed_work(&cli_data->work_buffer, msecs_to_jiffies(AMD_SFH_IDLE_LOOP));
+}
+
+int amd_sfh_hid_client_init(struct amd_mp2_dev *privdata)
+{
+	struct amdtp_cl_data *cl_data = privdata->cl_data;
+	struct amd_mp2_sensor_info info;
+	struct device *dev;
+	u32 feature_report_size;
+	u32 input_report_size;
+	u8 cl_idx;
+	int rc, i;
+
+	dev = &privdata->pdev->dev;
+	cl_data = kzalloc(sizeof(*cl_data), GFP_KERNEL);
+	if (!cl_data)
+		return -ENOMEM;
+
+	cl_data->num_hid_devices = amd_mp2_get_sensor_num(privdata, &cl_data->sensor_idx[0]);
+
+	INIT_DELAYED_WORK(&cl_data->work, amd_sfh_work);
+	INIT_DELAYED_WORK(&cl_data->work_buffer, amd_sfh_work_buffer);
+	INIT_LIST_HEAD(&req_list.list);
+
+	for (i = 0; i < cl_data->num_hid_devices; i++) {
+		cl_data->sensor_virt_addr[i] = dma_alloc_coherent(dev, sizeof(int) * 8,
+								  &cl_data->sensor_phys_addr[i],
+								  GFP_KERNEL);
+		cl_data->sensor_sts[i] = 0;
+		cl_data->sensor_requested_cnt[i] = 0;
+		cl_data->cur_hid_dev = i;
+		cl_idx = cl_data->sensor_idx[i];
+		cl_data->report_descr_sz[i] = get_descr_sz(cl_idx, descr_size);
+		if (!cl_data->report_descr_sz[i]) {
+			rc = -EINVAL;
+			goto cleanup;
+		}
+		feature_report_size = get_descr_sz(cl_idx, feature_size);
+		if (!feature_report_size) {
+			rc = -EINVAL;
+			goto cleanup;
+		}
+		input_report_size =  get_descr_sz(cl_idx, input_size);
+		if (!input_report_size) {
+			rc = -EINVAL;
+			goto cleanup;
+		}
+		cl_data->feature_report[i] = kzalloc(feature_report_size, GFP_KERNEL);
+		if (!cl_data->feature_report[i]) {
+			rc = -ENOMEM;
+			goto cleanup;
+		}
+		cl_data->input_report[i] = kzalloc(input_report_size, GFP_KERNEL);
+		if (!cl_data->input_report[i]) {
+			rc = -ENOMEM;
+			goto cleanup;
+		}
+		info.period = msecs_to_jiffies(AMD_SFH_IDLE_LOOP);
+		info.sensor_idx = cl_idx;
+		info.phys_address = cl_data->sensor_phys_addr[i];
+
+		cl_data->report_descr[i] = kzalloc(cl_data->report_descr_sz[i], GFP_KERNEL);
+		if (!cl_data->report_descr[i]) {
+			rc = -ENOMEM;
+			goto cleanup;
+		}
+		rc = get_report_descriptor(cl_idx, cl_data->report_descr[i]);
+		if (rc)
+			return rc;
+		rc = amdtp_hid_probe(cl_data->cur_hid_dev, cl_data);
+		if (rc)
+			return rc;
+		amd_start_sensor(privdata, info);
+		cl_data->sensor_sts[i] = 1;
+	}
+	privdata->cl_data = cl_data;
+	schedule_delayed_work(&cl_data->work_buffer, msecs_to_jiffies(AMD_SFH_IDLE_LOOP));
+	return 0;
+
+cleanup:
+	for (i = 0; i < cl_data->num_hid_devices; i++) {
+		if (cl_data->sensor_virt_addr[i]) {
+			dma_free_coherent(&privdata->pdev->dev, 8 * sizeof(int),
+					  cl_data->sensor_virt_addr[i],
+					  cl_data->sensor_phys_addr[i]);
+		}
+		kfree(cl_data->feature_report[i]);
+		kfree(cl_data->input_report[i]);
+		kfree(cl_data->report_descr[i]);
+	}
+	kfree(cl_data);
+	return rc;
+}
+
+int amd_sfh_hid_client_deinit(struct amd_mp2_dev *privdata)
+{
+	struct amdtp_cl_data *cl_data = privdata->cl_data;
+	int i;
+
+	for (i = 0; i < cl_data->num_hid_devices; i++)
+		amd_stop_sensor(privdata, i);
+
+	cancel_delayed_work_sync(&cl_data->work);
+	cancel_delayed_work_sync(&cl_data->work_buffer);
+	amdtp_hid_remove(cl_data);
+
+	for (i = 0; i < cl_data->num_hid_devices; i++) {
+		if (cl_data->sensor_virt_addr[i]) {
+			dma_free_coherent(&privdata->pdev->dev, 8 * sizeof(int),
+					  cl_data->sensor_virt_addr[i],
+					  cl_data->sensor_phys_addr[i]);
+		}
+	}
+	kfree(cl_data);
+	return 0;
+}
diff --git a/drivers/hid/amd-sfh-hid/amd_sfh_hid.c b/drivers/hid/amd-sfh-hid/amd_sfh_hid.c
new file mode 100644
index 000000000000..a471079a3bd0
--- /dev/null
+++ b/drivers/hid/amd-sfh-hid/amd_sfh_hid.c
@@ -0,0 +1,174 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * AMD MP2 Sensors transport driver
+ *
+ * Authors: Nehal Bakulchandra Shah <Nehal-bakulchandra.shah@amd.com>
+ *	    Sandeep Singh <sandeep.singh@amd.com>
+ */
+#include <linux/hid.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+
+#include "amd_sfh_hid.h"
+
+#define AMD_SFH_RESPONSE_TIMEOUT	1500
+
+/**
+ * amdtp_hid_parse() - hid-core .parse() callback
+ * @hid:	hid device instance
+ *
+ * This function gets called during call to hid_add_device
+ *
+ * Return: 0 on success and non zero on error
+ */
+static int amdtp_hid_parse(struct hid_device *hid)
+{
+	struct amdtp_hid_data *hid_data = hid->driver_data;
+	struct amdtp_cl_data *cli_data = hid_data->cli_data;
+
+	return hid_parse_report(hid, cli_data->report_descr[hid_data->index],
+			      cli_data->report_descr_sz[hid_data->index]);
+}
+
+/* Empty callbacks with success return code */
+static int amdtp_hid_start(struct hid_device *hid)
+{
+	return 0;
+}
+
+static void amdtp_hid_stop(struct hid_device *hid)
+{
+}
+
+static int amdtp_hid_open(struct hid_device *hid)
+{
+	return 0;
+}
+
+static void amdtp_hid_close(struct hid_device *hid)
+{
+}
+
+static int amdtp_raw_request(struct hid_device *hdev, u8 reportnum,
+			     u8 *buf, size_t len, u8 rtype, int reqtype)
+{
+	return 0;
+}
+
+static void amdtp_hid_request(struct hid_device *hid, struct hid_report *rep, int reqtype)
+{
+	int rc;
+
+	switch (reqtype) {
+	case HID_REQ_GET_REPORT:
+		rc = amd_sfh_get_report(hid, rep->id, rep->type);
+		if (rc)
+			dev_err(&hid->dev, "AMDSFH  get report error\n");
+		break;
+	case HID_REQ_SET_REPORT:
+		amd_sfh_set_report(hid, rep->id, reqtype);
+		break;
+	default:
+		break;
+	}
+}
+
+static int amdtp_wait_for_response(struct hid_device *hid)
+{
+	struct amdtp_hid_data *hid_data =  hid->driver_data;
+	struct amdtp_cl_data *cli_data = hid_data->cli_data;
+	int i, ret = 0;
+
+	for (i = 0; i < cli_data->num_hid_devices; i++) {
+		if (cli_data->hid_sensor_hubs[i] == hid)
+			break;
+	}
+
+	if (!cli_data->request_done[i])
+		ret = wait_event_interruptible_timeout(hid_data->hid_wait,
+						       cli_data->request_done[i],
+						       msecs_to_jiffies(AMD_SFH_RESPONSE_TIMEOUT));
+	if (ret < 0)
+		return -ETIMEDOUT;
+	else if (ret == -ERESTARTSYS)
+		return -ERESTARTSYS;
+	else
+		return 0;
+}
+
+void amdtp_hid_wakeup(struct hid_device *hid)
+{
+	struct amdtp_hid_data *hid_data = hid->driver_data;
+	struct amdtp_cl_data *cli_data = hid_data->cli_data;
+
+	cli_data->request_done[cli_data->cur_hid_dev] = true;
+	wake_up_interruptible(&hid_data->hid_wait);
+}
+
+static struct hid_ll_driver amdtp_hid_ll_driver = {
+	.parse	=	amdtp_hid_parse,
+	.start	=	amdtp_hid_start,
+	.stop	=	amdtp_hid_stop,
+	.open	=	amdtp_hid_open,
+	.close	=	amdtp_hid_close,
+	.request  =	amdtp_hid_request,
+	.wait	=	amdtp_wait_for_response,
+	.raw_request  =	amdtp_raw_request,
+};
+
+int amdtp_hid_probe(u32 cur_hid_dev, struct amdtp_cl_data *cli_data)
+{
+	struct hid_device *hid;
+	struct amdtp_hid_data *hid_data;
+	int rc;
+
+	hid = hid_allocate_device();
+	if (IS_ERR(hid))
+		return PTR_ERR(hid);
+
+	hid_data = kzalloc(sizeof(*hid_data), GFP_KERNEL);
+	if (!hid_data) {
+		rc = -ENOMEM;
+		goto err_hid_data;
+	}
+
+	hid->ll_driver = &amdtp_hid_ll_driver;
+	hid_data->index = cur_hid_dev;
+	hid_data->cli_data = cli_data;
+	init_waitqueue_head(&hid_data->hid_wait);
+
+	hid->driver_data = hid_data;
+	cli_data->hid_sensor_hubs[cur_hid_dev] = hid;
+	hid->bus = BUS_AMD_AMDTP;
+	hid->vendor = AMD_SFH_HID_VENDOR;
+	hid->product = AMD_SFH_HID_PRODUCT;
+	snprintf(hid->name, sizeof(hid->name), "%s %04X:%04X", "hid-amdtp",
+		 hid->vendor, hid->product);
+
+	rc = hid_add_device(hid);
+	if (rc)
+		goto err_hid_device;
+	return 0;
+
+err_hid_device:
+	kfree(hid_data);
+err_hid_data:
+	hid_destroy_device(hid);
+	return rc;
+}
+
+void amdtp_hid_remove(struct amdtp_cl_data *cli_data)
+{
+	int i;
+
+	for (i = 0; i < cli_data->num_hid_devices; ++i) {
+		kfree(cli_data->feature_report[i]);
+		kfree(cli_data->input_report[i]);
+		kfree(cli_data->report_descr[i]);
+		if (cli_data->hid_sensor_hubs[i]) {
+			kfree(cli_data->hid_sensor_hubs[i]->driver_data);
+			hid_destroy_device(cli_data->hid_sensor_hubs[i]);
+			cli_data->hid_sensor_hubs[i] = NULL;
+		}
+	}
+}
diff --git a/drivers/hid/amd-sfh-hid/amd_sfh_hid.h b/drivers/hid/amd-sfh-hid/amd_sfh_hid.h
new file mode 100644
index 000000000000..6be0783d885c
--- /dev/null
+++ b/drivers/hid/amd-sfh-hid/amd_sfh_hid.h
@@ -0,0 +1,67 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * AMD MP2 Sensors transport driver
+ *
+ * Authors: Nehal Bakulchandra Shah <Nehal-bakulchandra.shah@amd.com>
+ *	    Sandeep Singh <sandeep.singh@amd.com>
+ */
+
+#ifndef AMDSFH_HID_H
+#define AMDSFH_HID_H
+
+#define MAX_HID_DEVICES		4
+#define BUS_AMD_AMDTP		0x20
+#define AMD_SFH_HID_VENDOR	0x1022
+#define AMD_SFH_HID_PRODUCT	0x0001
+
+struct amdtp_cl_data {
+	u8 init_done;
+	u32 cur_hid_dev;
+	u32 hid_dev_count;
+	u32 num_hid_devices;
+	struct device_info *hid_devices;
+	u8  *report_descr[MAX_HID_DEVICES];
+	int report_descr_sz[MAX_HID_DEVICES];
+	struct hid_device *hid_sensor_hubs[MAX_HID_DEVICES];
+	u8 *hid_descr[MAX_HID_DEVICES];
+	int hid_descr_size[MAX_HID_DEVICES];
+	phys_addr_t phys_addr_base;
+	u32 *sensor_virt_addr[MAX_HID_DEVICES];
+	phys_addr_t sensor_phys_addr[MAX_HID_DEVICES];
+	u32 sensor_sts[MAX_HID_DEVICES];
+	u32 sensor_requested_cnt[MAX_HID_DEVICES];
+	u8 report_type[MAX_HID_DEVICES];
+	u8 report_id[MAX_HID_DEVICES];
+	u8 sensor_idx[MAX_HID_DEVICES];
+	u8 *feature_report[MAX_HID_DEVICES];
+	u8 *input_report[MAX_HID_DEVICES];
+	u8 request_done[MAX_HID_DEVICES];
+	struct delayed_work work;
+	struct delayed_work work_buffer;
+};
+
+/**
+ * struct amdtp_hid_data - Per instance HID data
+ * @index:		Device index in the order of enumeration
+ * @request_done:	Get Feature/Input report complete flag
+ *			used during get/set request from hid core
+ * @cli_data:		Link to the client instance
+ * @hid_wait:		Completion waitq
+ *
+ * Used to tie hid->driver data to driver client instance
+ */
+struct amdtp_hid_data {
+	int index;
+	struct amdtp_cl_data *cli_data;
+	wait_queue_head_t hid_wait;
+};
+
+/* Interface functions between HID LL driver and AMD SFH client */
+void hid_amdtp_set_feature(struct hid_device *hid, char *buf, u32 len, int report_id);
+void hid_amdtp_get_report(struct hid_device *hid, int report_id, int report_type);
+int amdtp_hid_probe(u32 cur_hid_dev, struct amdtp_cl_data *cli_data);
+void amdtp_hid_remove(struct amdtp_cl_data *cli_data);
+int amd_sfh_get_report(struct hid_device *hid, int report_id, int report_type);
+void amd_sfh_set_report(struct hid_device *hid, int report_id, int report_type);
+void amdtp_hid_wakeup(struct hid_device *hid);
+#endif