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Commit e46980a10a76ec3282dd6832c1974b880acd23d3

Authored by Samuel Ortiz 2013-04-09 06:51:38 +0800

Committed by Greg Kroah-Hartman 2013-04-09 07:57:15 +0800

Exists in smarc-l5.0.0_1.0.0-ga and in 5 other branches

mei: bus: Add device enabling and disabling API

It should be left to the drivers to enable and disable the device on the
MEI bus when e.g getting probed.
For drivers to be able to safely call the enable and disable hooks, the
mei_cl_ops must be set before it's probed and thus this should happen
before registering the device on the MEI bus. Hence the mei_cl_add_device()
prototype change.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Showing 4 changed files with 123 additions and 14 deletions Inline Diff

Documentation/misc-devices/mei/mei-client-bus.txt
drivers/misc/mei/bus.c
drivers/misc/mei/mei_dev.h
include/linux/mei_cl_bus.h

Documentation/misc-devices/mei/mei-client-bus.txt

Diff comments View file @ e46980a

 Intel(R) Management Engine (ME) Client bus API
 ===============================================
 Rationale
 =========
 MEI misc character device is useful for dedicated applications to send and receive
 data to the many FW appliance found in Intel's ME from the user space.
 However for some of the ME functionalities it make sense to leverage existing software
 stack and expose them through existing kernel subsystems.
 In order to plug seamlessly into the kernel device driver model we add kernel virtual
 bus abstraction on top of the MEI driver. This allows implementing linux kernel drivers
 for the various MEI features as a stand alone entities found in their respective subsystem.
 Existing device drivers can even potentially be re-used by adding an MEI CL bus layer to
 the existing code.
 MEI CL bus API
 ===========
 A driver implementation for an MEI Client is very similar to existing bus
 based device drivers. The driver registers itself as an MEI CL bus driver through
 the mei_cl_driver structure:
 struct mei_cl_driver {
 	struct device_driver driver;
 	const char *name;
 	const struct mei_cl_device_id *id_table;
 	int (*probe)(struct mei_cl_device *dev, const struct mei_cl_id *id);
 	int (*remove)(struct mei_cl_device *dev);
 };
 struct mei_cl_id {
 	char name[MEI_NAME_SIZE];
 	kernel_ulong_t driver_info;
 };
 The mei_cl_id structure allows the driver to bind itself against a device name.
 To actually register a driver on the ME Client bus one must call the mei_cl_add_driver()
 API. This is typically called at module init time.
 Once registered on the ME Client bus, a driver will typically try to do some I/O on
 this bus and this should be done through the mei_cl_send() and mei_cl_recv()
 routines. The latter is synchronous (blocks and sleeps until data shows up).
 In order for drivers to be notified of pending events waiting for them (e.g.
 an Rx event) they can register an event handler through the
 mei_cl_register_event_cb() routine. Currently only the MEI_EVENT_RX event
 will trigger an event handler call and the driver implementation is supposed
 to call mei_recv() from the event handler in order to fetch the pending
 received buffers.
 Example
 =======
 As a theoretical example let's pretend the ME comes with a "contact" NFC IP.
 The driver init and exit routines for this device would look like:
 #define CONTACT_DRIVER_NAME "contact"
 static struct mei_cl_device_id contact_mei_cl_tbl[] = {
 	{ CONTACT_DRIVER_NAME, },
 	/* required last entry */
 	{ }
 };
 MODULE_DEVICE_TABLE(mei_cl, contact_mei_cl_tbl);
 static struct mei_cl_driver contact_driver = {
        .id_table = contact_mei_tbl,
        .name = CONTACT_DRIVER_NAME,
        .probe = contact_probe,
        .remove = contact_remove,
 };
 static int contact_init(void)
 {
 	int r;
 	r = mei_cl_driver_register(&contact_driver);
 	if (r) {
 		pr_err(CONTACT_DRIVER_NAME ": driver registration failed\n");
 		return r;
 	}
 	return 0;
 }
 static void __exit contact_exit(void)
 {
 	mei_cl_driver_unregister(&contact_driver);
 }
 module_init(contact_init);
 module_exit(contact_exit);
 And the driver's simplified probe routine would look like that:
 int contact_probe(struct mei_cl_device *dev, struct mei_cl_device_id *id)
 {
 	struct contact_driver *contact;
 	[...]
+	mei_cl_enable_device(dev);
 	mei_cl_register_event_cb(dev, contact_event_cb, contact);
 	return 0;
  }
-In the probe routine the driver basically registers an ME bus event handler
+In the probe routine the driver first enable the MEI device and then registers
-which is as close as it can get to registering a threaded IRQ handler.
+an ME bus event handler which is as close as it can get to registering a
+threaded IRQ handler.
 The handler implementation will typically call some I/O routine depending on
 the pending events:
 #define MAX_NFC_PAYLOAD 128
 static void contact_event_cb(struct mei_cl_device *dev, u32 events,
 			     void *context)
 {
 	struct contact_driver *contact = context;
 	if (events & BIT(MEI_EVENT_RX)) {
 		u8 payload[MAX_NFC_PAYLOAD];
 		int payload_size;
 		payload_size = mei_recv(dev, payload, MAX_NFC_PAYLOAD);
 		if (payload_size <= 0)
 			return;
 		/* Hook to the NFC subsystem */
 		nfc_hci_recv_frame(contact->hdev, payload, payload_size);
 	}
 }

drivers/misc/mei/bus.c

Diff comments View file @ e46980a

 /*
  * Intel Management Engine Interface (Intel MEI) Linux driver
  * Copyright (c) 2012-2013, 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/device.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/init.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <linux/interrupt.h>
 #include <linux/pci.h>
 #include <linux/mei_cl_bus.h>
 #include "mei_dev.h"
 #include "hw-me.h"
 #include "client.h"
 #define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver)
 #define to_mei_cl_device(d) container_of(d, struct mei_cl_device, dev)
 static int mei_cl_device_match(struct device *dev, struct device_driver *drv)
 {
 	struct mei_cl_device *device = to_mei_cl_device(dev);
 	struct mei_cl_driver *driver = to_mei_cl_driver(drv);
 	const struct mei_cl_device_id *id;
 	if (!device)
 		return 0;
 	if (!driver || !driver->id_table)
 		return 0;
 	id = driver->id_table;
 	while (id->name[0]) {
 		if (!strcmp(dev_name(dev), id->name))
 			return 1;
 		id++;
 	}
 	return 0;
 }
 static int mei_cl_device_probe(struct device *dev)
 {
 	struct mei_cl_device *device = to_mei_cl_device(dev);
 	struct mei_cl_driver *driver;
 	struct mei_cl_device_id id;
 	if (!device)
 		return 0;
 	driver = to_mei_cl_driver(dev->driver);
 	if (!driver || !driver->probe)
 		return -ENODEV;
 	dev_dbg(dev, "Device probe\n");
 	strncpy(id.name, dev_name(dev), MEI_CL_NAME_SIZE);
 	return driver->probe(device, &id);
 }
 static int mei_cl_device_remove(struct device *dev)
 {
 	struct mei_cl_device *device = to_mei_cl_device(dev);
 	struct mei_cl_driver *driver;
 	if (!device || !dev->driver)
 		return 0;
 	if (device->event_cb) {
 		device->event_cb = NULL;
 		cancel_work_sync(&device->event_work);
 	}
 	driver = to_mei_cl_driver(dev->driver);
 	if (!driver->remove) {
 		dev->driver = NULL;
 		return 0;
 	}
 	return driver->remove(device);
 }
 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 			     char *buf)
 {
 	int len;
 	len = snprintf(buf, PAGE_SIZE, "mei:%s\n", dev_name(dev));
 	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 }
 static struct device_attribute mei_cl_dev_attrs[] = {
 	__ATTR_RO(modalias),
 	__ATTR_NULL,
 };
 static int mei_cl_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
 	if (add_uevent_var(env, "MODALIAS=mei:%s", dev_name(dev)))
 		return -ENOMEM;
 	return 0;
 }
 static struct bus_type mei_cl_bus_type = {
 	.name		= "mei",
 	.dev_attrs	= mei_cl_dev_attrs,
 	.match		= mei_cl_device_match,
 	.probe		= mei_cl_device_probe,
 	.remove		= mei_cl_device_remove,
 	.uevent		= mei_cl_uevent,
 };
 static void mei_cl_dev_release(struct device *dev)
 {
 	kfree(to_mei_cl_device(dev));
 }
 static struct device_type mei_cl_device_type = {
 	.release	= mei_cl_dev_release,
 };
 static struct mei_cl *mei_bus_find_mei_cl_by_uuid(struct mei_device *dev,
 						uuid_le uuid)
 {
 	struct mei_cl *cl, *next;
 	list_for_each_entry_safe(cl, next, &dev->device_list, device_link) {
 		if (!uuid_le_cmp(uuid, cl->device_uuid))
 			return cl;
 	}
 	return NULL;
 }
 struct mei_cl_device *mei_cl_add_device(struct mei_device *dev,
-				  uuid_le uuid, char *name)
+					uuid_le uuid, char *name,
+					struct mei_cl_ops *ops)
 {
 	struct mei_cl_device *device;
 	struct mei_cl *cl;
 	int status;
 	cl = mei_bus_find_mei_cl_by_uuid(dev, uuid);
 	if (cl == NULL)
 		return NULL;
 	device = kzalloc(sizeof(struct mei_cl_device), GFP_KERNEL);
 	if (!device)
 		return NULL;
 	device->cl = cl;
+	device->ops = ops;
 	device->dev.parent = &dev->pdev->dev;
 	device->dev.bus = &mei_cl_bus_type;
 	device->dev.type = &mei_cl_device_type;
 	dev_set_name(&device->dev, "%s", name);
 	status = device_register(&device->dev);
 	if (status) {
 		dev_err(&dev->pdev->dev, "Failed to register MEI device\n");
 		kfree(device);
 		return NULL;
 	}
 	cl->device = device;
 	dev_dbg(&device->dev, "client %s registered\n", name);
 	return device;
 }
 EXPORT_SYMBOL_GPL(mei_cl_add_device);
 void mei_cl_remove_device(struct mei_cl_device *device)
 {
 	device_unregister(&device->dev);
 }
 EXPORT_SYMBOL_GPL(mei_cl_remove_device);
 int __mei_cl_driver_register(struct mei_cl_driver *driver, struct module *owner)
 {
 	int err;
 	driver->driver.name = driver->name;
 	driver->driver.owner = owner;
 	driver->driver.bus = &mei_cl_bus_type;
 	err = driver_register(&driver->driver);
 	if (err)
 		return err;
 	pr_debug("mei: driver [%s] registered\n", driver->driver.name);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(__mei_cl_driver_register);
 void mei_cl_driver_unregister(struct mei_cl_driver *driver)
 {
 	driver_unregister(&driver->driver);
 	pr_debug("mei: driver [%s] unregistered\n", driver->driver.name);
 }
 EXPORT_SYMBOL_GPL(mei_cl_driver_unregister);
 static int ___mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
 			bool blocking)
 {
 	struct mei_device *dev;
 	struct mei_cl_cb *cb;
 	int id;
 	int rets;
 	if (WARN_ON(!cl || !cl->dev))
 		return -ENODEV;
 	dev = cl->dev;
 	if (cl->state != MEI_FILE_CONNECTED)
 		return -ENODEV;
 	/* Check if we have an ME client device */
 	id = mei_me_cl_by_id(dev, cl->me_client_id);
 	if (id < 0)
 		return -ENODEV;
 	if (length > dev->me_clients[id].props.max_msg_length)
 		return -EINVAL;
 	cb = mei_io_cb_init(cl, NULL);
 	if (!cb)
 		return -ENOMEM;
 	rets = mei_io_cb_alloc_req_buf(cb, length);
 	if (rets < 0) {
 		mei_io_cb_free(cb);
 		return rets;
 	}
 	memcpy(cb->request_buffer.data, buf, length);
 	mutex_lock(&dev->device_lock);
 	rets = mei_cl_write(cl, cb, blocking);
 	mutex_unlock(&dev->device_lock);
 	if (rets < 0)
 		mei_io_cb_free(cb);
 	return rets;
 }
 int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 {
 	struct mei_device *dev;
 	struct mei_cl_cb *cb;
 	size_t r_length;
 	int err;
 	if (WARN_ON(!cl || !cl->dev))
 		return -ENODEV;
 	dev = cl->dev;
 	mutex_lock(&dev->device_lock);
 	if (!cl->read_cb) {
 		err = mei_cl_read_start(cl);
 		if (err < 0) {
 			mutex_unlock(&dev->device_lock);
 			return err;
 		}
 	}
 	if (cl->reading_state != MEI_READ_COMPLETE &&
 	    !waitqueue_active(&cl->rx_wait)) {
 		mutex_unlock(&dev->device_lock);
 		if (wait_event_interruptible(cl->rx_wait,
 				(MEI_READ_COMPLETE == cl->reading_state))) {
 			if (signal_pending(current))
 				return -EINTR;
 			return -ERESTARTSYS;
 		}
 		mutex_lock(&dev->device_lock);
 	}
 	cb = cl->read_cb;
 	if (cl->reading_state != MEI_READ_COMPLETE) {
 		r_length = 0;
 		goto out;
 	}
 	r_length = min_t(size_t, length, cb->buf_idx);
 	memcpy(buf, cb->response_buffer.data, r_length);
 	mei_io_cb_free(cb);
 	cl->reading_state = MEI_IDLE;
 	cl->read_cb = NULL;
 out:
 	mutex_unlock(&dev->device_lock);
 	return r_length;
 }
 inline int __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length)
 {
 	return ___mei_cl_send(cl, buf, length, 0);
 }
 inline int __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length)
 {
 	return ___mei_cl_send(cl, buf, length, 1);
 }
 int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length)
 {
 	struct mei_cl *cl = device->cl;
 	if (cl == NULL)
 		return -ENODEV;
 	if (device->ops && device->ops->send)
 		return device->ops->send(device, buf, length);
 	return __mei_cl_send(cl, buf, length);
 }
 EXPORT_SYMBOL_GPL(mei_cl_send);
 int mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length)
 {
 	struct mei_cl *cl =  device->cl;
 	if (cl == NULL)
 		return -ENODEV;
 	if (device->ops && device->ops->recv)
 		return device->ops->recv(device, buf, length);
 	return __mei_cl_recv(cl, buf, length);
 }
 EXPORT_SYMBOL_GPL(mei_cl_recv);
 static void mei_bus_event_work(struct work_struct *work)
 {
 	struct mei_cl_device *device;
 	device = container_of(work, struct mei_cl_device, event_work);
 	if (device->event_cb)
 		device->event_cb(device, device->events, device->event_context);
 	device->events = 0;
 	/* Prepare for the next read */
 	mei_cl_read_start(device->cl);
 }
 int mei_cl_register_event_cb(struct mei_cl_device *device,
 			  mei_cl_event_cb_t event_cb, void *context)
 {
 	if (device->event_cb)
 		return -EALREADY;
 	device->events = 0;
 	device->event_cb = event_cb;
 	device->event_context = context;
 	INIT_WORK(&device->event_work, mei_bus_event_work);
 	mei_cl_read_start(device->cl);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(mei_cl_register_event_cb);
 void *mei_cl_get_drvdata(const struct mei_cl_device *device)
 {
 	return dev_get_drvdata(&device->dev);
 }
 EXPORT_SYMBOL_GPL(mei_cl_get_drvdata);
 void mei_cl_set_drvdata(struct mei_cl_device *device, void *data)
 {
 	dev_set_drvdata(&device->dev, data);
 }
 EXPORT_SYMBOL_GPL(mei_cl_set_drvdata);
+int mei_cl_enable_device(struct mei_cl_device *device)
+{
+	int err;
+	struct mei_device *dev;
+	struct mei_cl *cl = device->cl;
+	if (cl == NULL)
+		return -ENODEV;
+	dev = cl->dev;
+	mutex_lock(&dev->device_lock);
+	cl->state = MEI_FILE_CONNECTING;
+	err = mei_cl_connect(cl, NULL);
+	if (err < 0) {
+		mutex_unlock(&dev->device_lock);
+		dev_err(&dev->pdev->dev, "Could not connect to the ME client");
+		return err;
+	}
+	mutex_unlock(&dev->device_lock);
+	if (device->event_cb && !cl->read_cb)
+		mei_cl_read_start(device->cl);
+	if (!device->ops || !device->ops->enable)
+		return 0;
+	return device->ops->enable(device);
+}
+EXPORT_SYMBOL_GPL(mei_cl_enable_device);
+int mei_cl_disable_device(struct mei_cl_device *device)
+{
+	int err;
+	struct mei_device *dev;
+	struct mei_cl *cl = device->cl;
+	if (cl == NULL)
+		return -ENODEV;
+	dev = cl->dev;
+	mutex_lock(&dev->device_lock);
+	if (cl->state != MEI_FILE_CONNECTED) {
+		mutex_unlock(&dev->device_lock);
+		dev_err(&dev->pdev->dev, "Already disconnected");
+		return 0;
+	}
+	cl->state = MEI_FILE_DISCONNECTING;
+	err = mei_cl_disconnect(cl);
+	if (err < 0) {
+		mutex_unlock(&dev->device_lock);
+		dev_err(&dev->pdev->dev,
+			"Could not disconnect from the ME client");
+		return err;
+	}
+	/* Flush queues and remove any pending read */
+	mei_cl_flush_queues(cl);
+	if (cl->read_cb) {
+		struct mei_cl_cb *cb = NULL;
+		cb = mei_cl_find_read_cb(cl);
+		/* Remove entry from read list */
+		if (cb)
+			list_del(&cb->list);
+		cb = cl->read_cb;
+		cl->read_cb = NULL;
+		if (cb) {
+			mei_io_cb_free(cb);
+			cb = NULL;
+		}
+	}
+	mutex_unlock(&dev->device_lock);
+	if (!device->ops || !device->ops->disable)
+		return 0;
+	return device->ops->disable(device);
+}
+EXPORT_SYMBOL_GPL(mei_cl_disable_device);
 void mei_cl_bus_rx_event(struct mei_cl *cl)
 {
 	struct mei_cl_device *device = cl->device;
 	if (!device || !device->event_cb)
 		return;
 	set_bit(MEI_CL_EVENT_RX, &device->events);
 	schedule_work(&device->event_work);
 }
 int __init mei_cl_bus_init(void)
 {
 	return bus_register(&mei_cl_bus_type);
 }
 void __exit mei_cl_bus_exit(void)
 {
 	bus_unregister(&mei_cl_bus_type);
 }

drivers/misc/mei/mei_dev.h

Diff comments View file @ e46980a

 /*
  *
  * Intel Management Engine Interface (Intel MEI) Linux driver
  * Copyright (c) 2003-2012, 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 _MEI_DEV_H_
 #define _MEI_DEV_H_
 #include <linux/types.h>
 #include <linux/watchdog.h>
 #include <linux/poll.h>
 #include <linux/mei.h>
 #include <linux/mei_cl_bus.h>
 #include "hw.h"
 #include "hw-me-regs.h"
 /*
  * watch dog definition
  */
 #define MEI_WD_HDR_SIZE       4
 #define MEI_WD_STOP_MSG_SIZE  MEI_WD_HDR_SIZE
 #define MEI_WD_START_MSG_SIZE (MEI_WD_HDR_SIZE + 16)
 #define MEI_WD_DEFAULT_TIMEOUT   120  /* seconds */
 #define MEI_WD_MIN_TIMEOUT       120  /* seconds */
 #define MEI_WD_MAX_TIMEOUT     65535  /* seconds */
 #define MEI_WD_STOP_TIMEOUT      10 /* msecs */
 #define MEI_WD_STATE_INDEPENDENCE_MSG_SENT       (1 << 0)
 #define MEI_RD_MSG_BUF_SIZE           (128 * sizeof(u32))
 /*
  * AMTHI Client UUID
  */
 extern const uuid_le mei_amthif_guid;
 /*
  * Watchdog Client UUID
  */
 extern const uuid_le mei_wd_guid;
 /*
  * Watchdog independence state message
  */
 extern const u8 mei_wd_state_independence_msg[3][4];
 /*
  * Number of Maximum MEI Clients
  */
 #define MEI_CLIENTS_MAX 256
 /*
  * Number of File descriptors/handles
  * that can be opened to the driver.
  *
  * Limit to 255: 256 Total Clients
  * minus internal client for MEI Bus Messags
  */
 #define  MEI_MAX_OPEN_HANDLE_COUNT (MEI_CLIENTS_MAX - 1)
 /*
  * Internal Clients Number
  */
 #define MEI_HOST_CLIENT_ID_ANY        (-1)
 #define MEI_HBM_HOST_CLIENT_ID         0 /* not used, just for documentation */
 #define MEI_WD_HOST_CLIENT_ID          1
 #define MEI_IAMTHIF_HOST_CLIENT_ID     2
 /* File state */
 enum file_state {
 	MEI_FILE_INITIALIZING = 0,
 	MEI_FILE_CONNECTING,
 	MEI_FILE_CONNECTED,
 	MEI_FILE_DISCONNECTING,
 	MEI_FILE_DISCONNECTED
 };
 /* MEI device states */
 enum mei_dev_state {
 	MEI_DEV_INITIALIZING = 0,
 	MEI_DEV_INIT_CLIENTS,
 	MEI_DEV_ENABLED,
 	MEI_DEV_RESETING,
 	MEI_DEV_DISABLED,
 	MEI_DEV_POWER_DOWN,
 	MEI_DEV_POWER_UP
 };
 const char *mei_dev_state_str(int state);
 /* init clients states*/
 enum mei_init_clients_states {
 	MEI_START_MESSAGE = 0,
 	MEI_ENUM_CLIENTS_MESSAGE,
 	MEI_CLIENT_PROPERTIES_MESSAGE
 };
 enum iamthif_states {
 	MEI_IAMTHIF_IDLE,
 	MEI_IAMTHIF_WRITING,
 	MEI_IAMTHIF_FLOW_CONTROL,
 	MEI_IAMTHIF_READING,
 	MEI_IAMTHIF_READ_COMPLETE
 };
 enum mei_file_transaction_states {
 	MEI_IDLE,
 	MEI_WRITING,
 	MEI_WRITE_COMPLETE,
 	MEI_FLOW_CONTROL,
 	MEI_READING,
 	MEI_READ_COMPLETE
 };
 enum mei_wd_states {
 	MEI_WD_IDLE,
 	MEI_WD_RUNNING,
 	MEI_WD_STOPPING,
 };
 /**
  * enum mei_cb_file_ops  - file operation associated with the callback
  * @MEI_FOP_READ   - read
  * @MEI_FOP_WRITE  - write
  * @MEI_FOP_IOCTL  - ioctl
  * @MEI_FOP_OPEN   - open
  * @MEI_FOP_CLOSE  - close
  */
 enum mei_cb_file_ops {
 	MEI_FOP_READ = 0,
 	MEI_FOP_WRITE,
 	MEI_FOP_IOCTL,
 	MEI_FOP_OPEN,
 	MEI_FOP_CLOSE
 };
 /*
  * Intel MEI message data struct
  */
 struct mei_msg_data {
 	u32 size;
 	unsigned char *data;
 };
 /**
  * struct mei_me_client - representation of me (fw) client
  *
  * @props  - client properties
  * @client_id - me client id
  * @mei_flow_ctrl_creds - flow control credits
  */
 struct mei_me_client {
 	struct mei_client_properties props;
 	u8 client_id;
 	u8 mei_flow_ctrl_creds;
 };
 struct mei_cl;
 /**
  * struct mei_cl_cb - file operation callback structure
  *
  * @cl - file client who is running this operation
  * @fop_type - file operation type
  */
 struct mei_cl_cb {
 	struct list_head list;
 	struct mei_cl *cl;
 	enum mei_cb_file_ops fop_type;
 	struct mei_msg_data request_buffer;
 	struct mei_msg_data response_buffer;
 	unsigned long buf_idx;
 	unsigned long read_time;
 	struct file *file_object;
 };
 /* MEI client instance carried as file->pirvate_data*/
 struct mei_cl {
 	struct list_head link;
 	struct mei_device *dev;
 	enum file_state state;
 	wait_queue_head_t tx_wait;
 	wait_queue_head_t rx_wait;
 	wait_queue_head_t wait;
 	int status;
 	/* ID of client connected */
 	u8 host_client_id;
 	u8 me_client_id;
 	u8 mei_flow_ctrl_creds;
 	u8 timer_count;
 	enum mei_file_transaction_states reading_state;
 	enum mei_file_transaction_states writing_state;
 	int sm_state;
 	struct mei_cl_cb *read_cb;
 	/* MEI CL bus data */
 	struct mei_cl_device *device;
 	struct list_head device_link;
 	uuid_le device_uuid;
 };
 /** struct mei_hw_ops
  *
  * @host_is_ready    - query for host readiness
  * @hw_is_ready      - query if hw is ready
  * @hw_reset         - reset hw
  * @hw_start         - start hw after reset
  * @hw_config        - configure hw
  * @intr_clear       - clear pending interrupts
  * @intr_enable      - enable interrupts
  * @intr_disable     - disable interrupts
  * @hbuf_free_slots  - query for write buffer empty slots
  * @hbuf_is_ready    - query if write buffer is empty
  * @hbuf_max_len     - query for write buffer max len
  * @write            - write a message to FW
  * @rdbuf_full_slots - query how many slots are filled
  * @read_hdr         - get first 4 bytes (header)
  * @read             - read a buffer from the FW
  */
 struct mei_hw_ops {
 	bool (*host_is_ready) (struct mei_device *dev);
 	bool (*hw_is_ready) (struct mei_device *dev);
 	void (*hw_reset) (struct mei_device *dev, bool enable);
 	int  (*hw_start) (struct mei_device *dev);
 	void (*hw_config) (struct mei_device *dev);
 	void (*intr_clear) (struct mei_device *dev);
 	void (*intr_enable) (struct mei_device *dev);
 	void (*intr_disable) (struct mei_device *dev);
 	int (*hbuf_free_slots) (struct mei_device *dev);
 	bool (*hbuf_is_ready) (struct mei_device *dev);
 	size_t (*hbuf_max_len) (const struct mei_device *dev);
 	int (*write)(struct mei_device *dev,
 		     struct mei_msg_hdr *hdr,
 		     unsigned char *buf);
 	int (*rdbuf_full_slots)(struct mei_device *dev);
 	u32 (*read_hdr)(const struct mei_device *dev);
 	int (*read) (struct mei_device *dev,
 		     unsigned char *buf, unsigned long len);
 };
 /* MEI bus API*/
-struct mei_cl_device *mei_cl_add_device(struct mei_device *dev,
-				  uuid_le uuid, char *name);
-void mei_cl_remove_device(struct mei_cl_device *device);
-int __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length);
-int __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length);
-int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length);
 /**
- * struct mei_cl_transport_ops - MEI CL device transport ops
+ * struct mei_cl_ops - MEI CL device ops
  * This structure allows ME host clients to implement technology
- * specific transport layers.
+ * specific operations.
  *
+ * @enable: Enable an MEI CL device. Some devices require specific
+ *	HECI commands to initialize completely.
+ * @disable: Disable an MEI CL device.
  * @send: Tx hook for the device. This allows ME host clients to trap
  *	the device driver buffers before actually physically
  *	pushing it to the ME.
  * @recv: Rx hook for the device. This allows ME host clients to trap the
  *	ME buffers before forwarding them to the device driver.
  */
-struct mei_cl_transport_ops {
+struct mei_cl_ops {
+	int (*enable)(struct mei_cl_device *device);
+	int (*disable)(struct mei_cl_device *device);
 	int (*send)(struct mei_cl_device *device, u8 *buf, size_t length);
 	int (*recv)(struct mei_cl_device *device, u8 *buf, size_t length);
 };
+struct mei_cl_device *mei_cl_add_device(struct mei_device *dev,
+					uuid_le uuid, char *name,
+					struct mei_cl_ops *ops);
+void mei_cl_remove_device(struct mei_cl_device *device);
+int __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length);
+int __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length);
+int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length);
 void mei_cl_bus_rx_event(struct mei_cl *cl);
 int mei_cl_bus_init(void);
 void mei_cl_bus_exit(void);
 /**
  * struct mei_cl_device - MEI device handle
  * An mei_cl_device pointer is returned from mei_add_device()
  * and links MEI bus clients to their actual ME host client pointer.
  * Drivers for MEI devices will get an mei_cl_device pointer
  * when being probed and shall use it for doing ME bus I/O.
  *
  * @dev: linux driver model device pointer
  * @uuid: me client uuid
  * @cl: mei client
  * @ops: ME transport ops
  * @event_cb: Drivers register this callback to get asynchronous ME
  *	events (e.g. Rx buffer pending) notifications.
  * @events: Events bitmask sent to the driver.
  * @priv_data: client private data
  */
 struct mei_cl_device {
 	struct device dev;
 	struct mei_cl *cl;
-	const struct mei_cl_transport_ops *ops;
+	const struct mei_cl_ops *ops;
 	struct work_struct event_work;
 	mei_cl_event_cb_t event_cb;
 	void *event_context;
 	unsigned long events;
 	void *priv_data;
 };
 /**
  * struct mei_device -  MEI private device struct
  * @mem_addr - mem mapped base register address
  * @hbuf_depth - depth of hardware host/write buffer is slots
  * @hbuf_is_ready - query if the host host/write buffer is ready
  * @wr_msg - the buffer for hbm control messages
  * @wr_ext_msg - the buffer for hbm control responses (set in read cycle)
  */
 struct mei_device {
 	struct pci_dev *pdev;	/* pointer to pci device struct */
 	/*
 	 * lists of queues
 	 */
 	/* array of pointers to aio lists */
 	struct mei_cl_cb read_list;		/* driver read queue */
 	struct mei_cl_cb write_list;		/* driver write queue */
 	struct mei_cl_cb write_waiting_list;	/* write waiting queue */
 	struct mei_cl_cb ctrl_wr_list;		/* managed write IOCTL list */
 	struct mei_cl_cb ctrl_rd_list;		/* managed read IOCTL list */
 	/*
 	 * list of files
 	 */
 	struct list_head file_list;
 	long open_handle_count;
 	/*
 	 * lock for the device
 	 */
 	struct mutex device_lock; /* device lock */
 	struct delayed_work timer_work;	/* MEI timer delayed work (timeouts) */
 	bool recvd_hw_ready;
 	bool recvd_msg;
 	/*
 	 * waiting queue for receive message from FW
 	 */
 	wait_queue_head_t wait_hw_ready;
 	wait_queue_head_t wait_recvd_msg;
 	wait_queue_head_t wait_stop_wd;
 	/*
 	 * mei device  states
 	 */
 	enum mei_dev_state dev_state;
 	enum mei_init_clients_states init_clients_state;
 	u16 init_clients_timer;
 	unsigned char rd_msg_buf[MEI_RD_MSG_BUF_SIZE];	/* control messages */
 	u32 rd_msg_hdr;
 	/* write buffer */
 	u8 hbuf_depth;
 	bool hbuf_is_ready;
 	/* used for control messages */
 	struct {
 		struct mei_msg_hdr hdr;
 		unsigned char data[128];
 	} wr_msg;
 	struct {
 		struct mei_msg_hdr hdr;
 		unsigned char data[4];	/* All HBM messages are 4 bytes */
 	} wr_ext_msg;		/* for control responses */
 	struct hbm_version version;
 	struct mei_me_client *me_clients; /* Note: memory has to be allocated */
 	DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
 	DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
 	u8 me_clients_num;
 	u8 me_client_presentation_num;
 	u8 me_client_index;
 	struct mei_cl wd_cl;
 	enum mei_wd_states wd_state;
 	bool wd_pending;
 	u16 wd_timeout;
 	unsigned char wd_data[MEI_WD_START_MSG_SIZE];
 	/* amthif list for cmd waiting */
 	struct mei_cl_cb amthif_cmd_list;
 	/* driver managed amthif list for reading completed amthif cmd data */
 	struct mei_cl_cb amthif_rd_complete_list;
 	struct file *iamthif_file_object;
 	struct mei_cl iamthif_cl;
 	struct mei_cl_cb *iamthif_current_cb;
 	int iamthif_mtu;
 	unsigned long iamthif_timer;
 	u32 iamthif_stall_timer;
 	unsigned char *iamthif_msg_buf; /* Note: memory has to be allocated */
 	u32 iamthif_msg_buf_size;
 	u32 iamthif_msg_buf_index;
 	enum iamthif_states iamthif_state;
 	bool iamthif_flow_control_pending;
 	bool iamthif_ioctl;
 	bool iamthif_canceled;
 	struct work_struct init_work;
 	/* List of bus devices */
 	struct list_head device_list;
 #if IS_ENABLED(CONFIG_DEBUG_FS)
 	struct dentry *dbgfs_dir;
 #endif /* CONFIG_DEBUG_FS */
 	const struct mei_hw_ops *ops;
 	char hw[0] __aligned(sizeof(void *));
 };
 static inline unsigned long mei_secs_to_jiffies(unsigned long sec)
 {
 	return msecs_to_jiffies(sec * MSEC_PER_SEC);
 }
 /**
  * mei_data2slots - get slots - number of (dwords) from a message length
  *	+ size of the mei header
  * @length - size of the messages in bytes
  * returns  - number of slots
  */
 static inline u32 mei_data2slots(size_t length)
 {
 	return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, 4);
 }
 /*
  * mei init function prototypes
  */
 void mei_device_init(struct mei_device *dev);
 void mei_reset(struct mei_device *dev, int interrupts);
 int mei_start(struct mei_device *dev);
 void mei_stop(struct mei_device *dev);
 /*
  *  MEI interrupt functions prototype
  */
 void mei_timer(struct work_struct *work);
 int mei_irq_read_handler(struct mei_device *dev,
 		struct mei_cl_cb *cmpl_list, s32 *slots);
 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list);
 void mei_irq_compl_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list);
 /*
  * AMTHIF - AMT Host Interface Functions
  */
 void mei_amthif_reset_params(struct mei_device *dev);
 int mei_amthif_host_init(struct mei_device *dev);
 int mei_amthif_write(struct mei_device *dev, struct mei_cl_cb *priv_cb);
 int mei_amthif_read(struct mei_device *dev, struct file *file,
 		char __user *ubuf, size_t length, loff_t *offset);
 unsigned int mei_amthif_poll(struct mei_device *dev,
 		struct file *file, poll_table *wait);
 int mei_amthif_release(struct mei_device *dev, struct file *file);
 struct mei_cl_cb *mei_amthif_find_read_list_entry(struct mei_device *dev,
 						struct file *file);
 void mei_amthif_run_next_cmd(struct mei_device *dev);
 int mei_amthif_irq_write_complete(struct mei_device *dev, s32 *slots,
 			struct mei_cl_cb *cb, struct mei_cl_cb *cmpl_list);
 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb);
 int mei_amthif_irq_read_message(struct mei_cl_cb *complete_list,
 		struct mei_device *dev, struct mei_msg_hdr *mei_hdr);
 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots);
 int mei_wd_send(struct mei_device *dev);
 int mei_wd_stop(struct mei_device *dev);
 int mei_wd_host_init(struct mei_device *dev);
 /*
  * mei_watchdog_register  - Registering watchdog interface
  *   once we got connection to the WD Client
  * @dev - mei device
  */
 void mei_watchdog_register(struct mei_device *dev);
 /*
  * mei_watchdog_unregister  - Unregistering watchdog interface
  * @dev - mei device
  */
 void mei_watchdog_unregister(struct mei_device *dev);
 /*
  * Register Access Function
  */
 static inline void mei_hw_config(struct mei_device *dev)
 {
 	dev->ops->hw_config(dev);
 }
 static inline void mei_hw_reset(struct mei_device *dev, bool enable)
 {
 	dev->ops->hw_reset(dev, enable);
 }
 static inline void mei_hw_start(struct mei_device *dev)
 {
 	dev->ops->hw_start(dev);
 }
 static inline void mei_clear_interrupts(struct mei_device *dev)
 {
 	dev->ops->intr_clear(dev);
 }
 static inline void mei_enable_interrupts(struct mei_device *dev)
 {
 	dev->ops->intr_enable(dev);
 }
 static inline void mei_disable_interrupts(struct mei_device *dev)
 {
 	dev->ops->intr_disable(dev);
 }
 static inline bool mei_host_is_ready(struct mei_device *dev)
 {
 	return dev->ops->host_is_ready(dev);
 }
 static inline bool mei_hw_is_ready(struct mei_device *dev)
 {
 	return dev->ops->hw_is_ready(dev);
 }
 static inline bool mei_hbuf_is_ready(struct mei_device *dev)
 {
 	return dev->ops->hbuf_is_ready(dev);
 }
 static inline int mei_hbuf_empty_slots(struct mei_device *dev)
 {
 	return dev->ops->hbuf_free_slots(dev);
 }
 static inline size_t mei_hbuf_max_len(const struct mei_device *dev)
 {
 	return dev->ops->hbuf_max_len(dev);
 }
 static inline int mei_write_message(struct mei_device *dev,
 			struct mei_msg_hdr *hdr,
 			unsigned char *buf)
 {
 	return dev->ops->write(dev, hdr, buf);
 }
 static inline u32 mei_read_hdr(const struct mei_device *dev)
 {
 	return dev->ops->read_hdr(dev);
 }
 static inline void mei_read_slots(struct mei_device *dev,
 		     unsigned char *buf, unsigned long len)
 {
 	dev->ops->read(dev, buf, len);
 }
 static inline int mei_count_full_read_slots(struct mei_device *dev)
 {
 	return dev->ops->rdbuf_full_slots(dev);
 }
 #if IS_ENABLED(CONFIG_DEBUG_FS)
 int mei_dbgfs_register(struct mei_device *dev, const char *name);
 void mei_dbgfs_deregister(struct mei_device *dev);
 #else
 static inline int mei_dbgfs_register(struct mei_device *dev, const char *name)
 {
 	return 0;
 }
 static inline void mei_dbgfs_deregister(struct mei_device *dev) {}
 #endif /* CONFIG_DEBUG_FS */
 int mei_register(struct mei_device *dev);
 void mei_deregister(struct mei_device *dev);

include/linux/mei_cl_bus.h

Diff comments View file @ e46980a

 #ifndef _LINUX_MEI_CL_BUS_H
 #define _LINUX_MEI_CL_BUS_H
 #include <linux/device.h>
 #include <linux/uuid.h>
 struct mei_cl_device;
 struct mei_cl_driver {
 	struct device_driver driver;
 	const char *name;
 	const struct mei_cl_device_id *id_table;
 	int (*probe)(struct mei_cl_device *dev,
 		     const struct mei_cl_device_id *id);
 	int (*remove)(struct mei_cl_device *dev);
 };
 int __mei_cl_driver_register(struct mei_cl_driver *driver,
 				struct module *owner);
 #define mei_cl_driver_register(driver)             \
 	__mei_cl_driver_register(driver, THIS_MODULE)
 void mei_cl_driver_unregister(struct mei_cl_driver *driver);
 int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length);
 int mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length);
 typedef void (*mei_cl_event_cb_t)(struct mei_cl_device *device,
 			       u32 events, void *context);
 int mei_cl_register_event_cb(struct mei_cl_device *device,
 			  mei_cl_event_cb_t read_cb, void *context);
 #define MEI_CL_EVENT_RX 0
 #define MEI_CL_EVENT_TX 1
 void *mei_cl_get_drvdata(const struct mei_cl_device *device);
 void mei_cl_set_drvdata(struct mei_cl_device *device, void *data);
+int mei_cl_enable_device(struct mei_cl_device *device);
+int mei_cl_disable_device(struct mei_cl_device *device);
 #endif /* _LINUX_MEI_CL_BUS_H */