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-rw-r--r--drivers/misc/mei/bus.c1257
1 files changed, 1257 insertions, 0 deletions
diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
new file mode 100644
index 000000000..9cdaa7f3a
--- /dev/null
+++ b/drivers/misc/mei/bus.c
@@ -0,0 +1,1257 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2012-2019, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/sched/signal.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/interrupt.h>
+#include <linux/mei_cl_bus.h>
+
+#include "mei_dev.h"
+#include "client.h"
+
+#define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver)
+
+/**
+ * __mei_cl_send - internal client send (write)
+ *
+ * @cl: host client
+ * @buf: buffer to send
+ * @length: buffer length
+ * @mode: sending mode
+ *
+ * Return: written size bytes or < 0 on error
+ */
+ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
+ unsigned int mode)
+{
+ struct mei_device *bus;
+ struct mei_cl_cb *cb;
+ ssize_t rets;
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -ENODEV;
+
+ bus = cl->dev;
+
+ mutex_lock(&bus->device_lock);
+ if (bus->dev_state != MEI_DEV_ENABLED) {
+ rets = -ENODEV;
+ goto out;
+ }
+
+ if (!mei_cl_is_connected(cl)) {
+ rets = -ENODEV;
+ goto out;
+ }
+
+ /* Check if we have an ME client device */
+ if (!mei_me_cl_is_active(cl->me_cl)) {
+ rets = -ENOTTY;
+ goto out;
+ }
+
+ if (length > mei_cl_mtu(cl)) {
+ rets = -EFBIG;
+ goto out;
+ }
+
+ while (cl->tx_cb_queued >= bus->tx_queue_limit) {
+ mutex_unlock(&bus->device_lock);
+ rets = wait_event_interruptible(cl->tx_wait,
+ cl->writing_state == MEI_WRITE_COMPLETE ||
+ (!mei_cl_is_connected(cl)));
+ mutex_lock(&bus->device_lock);
+ if (rets) {
+ if (signal_pending(current))
+ rets = -EINTR;
+ goto out;
+ }
+ if (!mei_cl_is_connected(cl)) {
+ rets = -ENODEV;
+ goto out;
+ }
+ }
+
+ cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, NULL);
+ if (!cb) {
+ rets = -ENOMEM;
+ goto out;
+ }
+
+ cb->internal = !!(mode & MEI_CL_IO_TX_INTERNAL);
+ cb->blocking = !!(mode & MEI_CL_IO_TX_BLOCKING);
+ memcpy(cb->buf.data, buf, length);
+
+ rets = mei_cl_write(cl, cb);
+
+out:
+ mutex_unlock(&bus->device_lock);
+
+ return rets;
+}
+
+/**
+ * __mei_cl_recv - internal client receive (read)
+ *
+ * @cl: host client
+ * @buf: buffer to receive
+ * @length: buffer length
+ * @mode: io mode
+ * @timeout: recv timeout, 0 for infinite timeout
+ *
+ * Return: read size in bytes of < 0 on error
+ */
+ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length,
+ unsigned int mode, unsigned long timeout)
+{
+ struct mei_device *bus;
+ struct mei_cl_cb *cb;
+ size_t r_length;
+ ssize_t rets;
+ bool nonblock = !!(mode & MEI_CL_IO_RX_NONBLOCK);
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -ENODEV;
+
+ bus = cl->dev;
+
+ mutex_lock(&bus->device_lock);
+ if (bus->dev_state != MEI_DEV_ENABLED) {
+ rets = -ENODEV;
+ goto out;
+ }
+
+ cb = mei_cl_read_cb(cl, NULL);
+ if (cb)
+ goto copy;
+
+ rets = mei_cl_read_start(cl, length, NULL);
+ if (rets && rets != -EBUSY)
+ goto out;
+
+ if (nonblock) {
+ rets = -EAGAIN;
+ goto out;
+ }
+
+ /* wait on event only if there is no other waiter */
+ /* synchronized under device mutex */
+ if (!waitqueue_active(&cl->rx_wait)) {
+
+ mutex_unlock(&bus->device_lock);
+
+ if (timeout) {
+ rets = wait_event_interruptible_timeout
+ (cl->rx_wait,
+ mei_cl_read_cb(cl, NULL) ||
+ (!mei_cl_is_connected(cl)),
+ msecs_to_jiffies(timeout));
+ if (rets == 0)
+ return -ETIME;
+ if (rets < 0) {
+ if (signal_pending(current))
+ return -EINTR;
+ return -ERESTARTSYS;
+ }
+ } else {
+ if (wait_event_interruptible
+ (cl->rx_wait,
+ mei_cl_read_cb(cl, NULL) ||
+ (!mei_cl_is_connected(cl)))) {
+ if (signal_pending(current))
+ return -EINTR;
+ return -ERESTARTSYS;
+ }
+ }
+
+ mutex_lock(&bus->device_lock);
+
+ if (!mei_cl_is_connected(cl)) {
+ rets = -ENODEV;
+ goto out;
+ }
+ }
+
+ cb = mei_cl_read_cb(cl, NULL);
+ if (!cb) {
+ rets = 0;
+ goto out;
+ }
+
+copy:
+ if (cb->status) {
+ rets = cb->status;
+ goto free;
+ }
+
+ r_length = min_t(size_t, length, cb->buf_idx);
+ memcpy(buf, cb->buf.data, r_length);
+ rets = r_length;
+
+free:
+ mei_cl_del_rd_completed(cl, cb);
+out:
+ mutex_unlock(&bus->device_lock);
+
+ return rets;
+}
+
+/**
+ * mei_cldev_send - me device send (write)
+ *
+ * @cldev: me client device
+ * @buf: buffer to send
+ * @length: buffer length
+ *
+ * Return: written size in bytes or < 0 on error
+ */
+ssize_t mei_cldev_send(struct mei_cl_device *cldev, u8 *buf, size_t length)
+{
+ struct mei_cl *cl = cldev->cl;
+
+ return __mei_cl_send(cl, buf, length, MEI_CL_IO_TX_BLOCKING);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_send);
+
+/**
+ * mei_cldev_recv_nonblock - non block client receive (read)
+ *
+ * @cldev: me client device
+ * @buf: buffer to receive
+ * @length: buffer length
+ *
+ * Return: read size in bytes of < 0 on error
+ * -EAGAIN if function will block.
+ */
+ssize_t mei_cldev_recv_nonblock(struct mei_cl_device *cldev, u8 *buf,
+ size_t length)
+{
+ struct mei_cl *cl = cldev->cl;
+
+ return __mei_cl_recv(cl, buf, length, MEI_CL_IO_RX_NONBLOCK, 0);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_recv_nonblock);
+
+/**
+ * mei_cldev_recv - client receive (read)
+ *
+ * @cldev: me client device
+ * @buf: buffer to receive
+ * @length: buffer length
+ *
+ * Return: read size in bytes of < 0 on error
+ */
+ssize_t mei_cldev_recv(struct mei_cl_device *cldev, u8 *buf, size_t length)
+{
+ struct mei_cl *cl = cldev->cl;
+
+ return __mei_cl_recv(cl, buf, length, 0, 0);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_recv);
+
+/**
+ * mei_cl_bus_rx_work - dispatch rx event for a bus device
+ *
+ * @work: work
+ */
+static void mei_cl_bus_rx_work(struct work_struct *work)
+{
+ struct mei_cl_device *cldev;
+ struct mei_device *bus;
+
+ cldev = container_of(work, struct mei_cl_device, rx_work);
+
+ bus = cldev->bus;
+
+ if (cldev->rx_cb)
+ cldev->rx_cb(cldev);
+
+ mutex_lock(&bus->device_lock);
+ mei_cl_read_start(cldev->cl, mei_cl_mtu(cldev->cl), NULL);
+ mutex_unlock(&bus->device_lock);
+}
+
+/**
+ * mei_cl_bus_notif_work - dispatch FW notif event for a bus device
+ *
+ * @work: work
+ */
+static void mei_cl_bus_notif_work(struct work_struct *work)
+{
+ struct mei_cl_device *cldev;
+
+ cldev = container_of(work, struct mei_cl_device, notif_work);
+
+ if (cldev->notif_cb)
+ cldev->notif_cb(cldev);
+}
+
+/**
+ * mei_cl_bus_notify_event - schedule notify cb on bus client
+ *
+ * @cl: host client
+ *
+ * Return: true if event was scheduled
+ * false if the client is not waiting for event
+ */
+bool mei_cl_bus_notify_event(struct mei_cl *cl)
+{
+ struct mei_cl_device *cldev = cl->cldev;
+
+ if (!cldev || !cldev->notif_cb)
+ return false;
+
+ if (!cl->notify_ev)
+ return false;
+
+ schedule_work(&cldev->notif_work);
+
+ cl->notify_ev = false;
+
+ return true;
+}
+
+/**
+ * mei_cl_bus_rx_event - schedule rx event
+ *
+ * @cl: host client
+ *
+ * Return: true if event was scheduled
+ * false if the client is not waiting for event
+ */
+bool mei_cl_bus_rx_event(struct mei_cl *cl)
+{
+ struct mei_cl_device *cldev = cl->cldev;
+
+ if (!cldev || !cldev->rx_cb)
+ return false;
+
+ schedule_work(&cldev->rx_work);
+
+ return true;
+}
+
+/**
+ * mei_cldev_register_rx_cb - register Rx event callback
+ *
+ * @cldev: me client devices
+ * @rx_cb: callback function
+ *
+ * Return: 0 on success
+ * -EALREADY if an callback is already registered
+ * <0 on other errors
+ */
+int mei_cldev_register_rx_cb(struct mei_cl_device *cldev, mei_cldev_cb_t rx_cb)
+{
+ struct mei_device *bus = cldev->bus;
+ int ret;
+
+ if (!rx_cb)
+ return -EINVAL;
+ if (cldev->rx_cb)
+ return -EALREADY;
+
+ cldev->rx_cb = rx_cb;
+ INIT_WORK(&cldev->rx_work, mei_cl_bus_rx_work);
+
+ mutex_lock(&bus->device_lock);
+ ret = mei_cl_read_start(cldev->cl, mei_cl_mtu(cldev->cl), NULL);
+ mutex_unlock(&bus->device_lock);
+ if (ret && ret != -EBUSY)
+ return ret;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_register_rx_cb);
+
+/**
+ * mei_cldev_register_notif_cb - register FW notification event callback
+ *
+ * @cldev: me client devices
+ * @notif_cb: callback function
+ *
+ * Return: 0 on success
+ * -EALREADY if an callback is already registered
+ * <0 on other errors
+ */
+int mei_cldev_register_notif_cb(struct mei_cl_device *cldev,
+ mei_cldev_cb_t notif_cb)
+{
+ struct mei_device *bus = cldev->bus;
+ int ret;
+
+ if (!notif_cb)
+ return -EINVAL;
+
+ if (cldev->notif_cb)
+ return -EALREADY;
+
+ cldev->notif_cb = notif_cb;
+ INIT_WORK(&cldev->notif_work, mei_cl_bus_notif_work);
+
+ mutex_lock(&bus->device_lock);
+ ret = mei_cl_notify_request(cldev->cl, NULL, 1);
+ mutex_unlock(&bus->device_lock);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_register_notif_cb);
+
+/**
+ * mei_cldev_get_drvdata - driver data getter
+ *
+ * @cldev: mei client device
+ *
+ * Return: driver private data
+ */
+void *mei_cldev_get_drvdata(const struct mei_cl_device *cldev)
+{
+ return dev_get_drvdata(&cldev->dev);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_get_drvdata);
+
+/**
+ * mei_cldev_set_drvdata - driver data setter
+ *
+ * @cldev: mei client device
+ * @data: data to store
+ */
+void mei_cldev_set_drvdata(struct mei_cl_device *cldev, void *data)
+{
+ dev_set_drvdata(&cldev->dev, data);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_set_drvdata);
+
+/**
+ * mei_cldev_uuid - return uuid of the underlying me client
+ *
+ * @cldev: mei client device
+ *
+ * Return: me client uuid
+ */
+const uuid_le *mei_cldev_uuid(const struct mei_cl_device *cldev)
+{
+ return mei_me_cl_uuid(cldev->me_cl);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_uuid);
+
+/**
+ * mei_cldev_ver - return protocol version of the underlying me client
+ *
+ * @cldev: mei client device
+ *
+ * Return: me client protocol version
+ */
+u8 mei_cldev_ver(const struct mei_cl_device *cldev)
+{
+ return mei_me_cl_ver(cldev->me_cl);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_ver);
+
+/**
+ * mei_cldev_enabled - check whether the device is enabled
+ *
+ * @cldev: mei client device
+ *
+ * Return: true if me client is initialized and connected
+ */
+bool mei_cldev_enabled(struct mei_cl_device *cldev)
+{
+ return mei_cl_is_connected(cldev->cl);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_enabled);
+
+/**
+ * mei_cl_bus_module_get - acquire module of the underlying
+ * hw driver.
+ *
+ * @cldev: mei client device
+ *
+ * Return: true on success; false if the module was removed.
+ */
+static bool mei_cl_bus_module_get(struct mei_cl_device *cldev)
+{
+ return try_module_get(cldev->bus->dev->driver->owner);
+}
+
+/**
+ * mei_cl_bus_module_put - release the underlying hw module.
+ *
+ * @cldev: mei client device
+ */
+static void mei_cl_bus_module_put(struct mei_cl_device *cldev)
+{
+ module_put(cldev->bus->dev->driver->owner);
+}
+
+/**
+ * mei_cl_bus_vtag - get bus vtag entry wrapper
+ * The tag for bus client is always first.
+ *
+ * @cl: host client
+ *
+ * Return: bus vtag or NULL
+ */
+static inline struct mei_cl_vtag *mei_cl_bus_vtag(struct mei_cl *cl)
+{
+ return list_first_entry_or_null(&cl->vtag_map,
+ struct mei_cl_vtag, list);
+}
+
+/**
+ * mei_cl_bus_vtag_alloc - add bus client entry to vtag map
+ *
+ * @cldev: me client device
+ *
+ * Return:
+ * * 0 on success
+ * * -ENOMEM if memory allocation failed
+ */
+static int mei_cl_bus_vtag_alloc(struct mei_cl_device *cldev)
+{
+ struct mei_cl *cl = cldev->cl;
+ struct mei_cl_vtag *cl_vtag;
+
+ /*
+ * Bail out if the client does not supports vtags
+ * or has already allocated one
+ */
+ if (mei_cl_vt_support_check(cl) || mei_cl_bus_vtag(cl))
+ return 0;
+
+ cl_vtag = mei_cl_vtag_alloc(NULL, 0);
+ if (IS_ERR(cl_vtag))
+ return -ENOMEM;
+
+ list_add_tail(&cl_vtag->list, &cl->vtag_map);
+
+ return 0;
+}
+
+/**
+ * mei_cl_bus_vtag_free - remove the bus entry from vtag map
+ *
+ * @cldev: me client device
+ */
+static void mei_cl_bus_vtag_free(struct mei_cl_device *cldev)
+{
+ struct mei_cl *cl = cldev->cl;
+ struct mei_cl_vtag *cl_vtag;
+
+ cl_vtag = mei_cl_bus_vtag(cl);
+ if (!cl_vtag)
+ return;
+
+ list_del(&cl_vtag->list);
+ kfree(cl_vtag);
+}
+
+/**
+ * mei_cldev_enable - enable me client device
+ * create connection with me client
+ *
+ * @cldev: me client device
+ *
+ * Return: 0 on success and < 0 on error
+ */
+int mei_cldev_enable(struct mei_cl_device *cldev)
+{
+ struct mei_device *bus = cldev->bus;
+ struct mei_cl *cl;
+ int ret;
+
+ cl = cldev->cl;
+
+ mutex_lock(&bus->device_lock);
+ if (cl->state == MEI_FILE_UNINITIALIZED) {
+ ret = mei_cl_link(cl);
+ if (ret)
+ goto out;
+ /* update pointers */
+ cl->cldev = cldev;
+ }
+
+ if (mei_cl_is_connected(cl)) {
+ ret = 0;
+ goto out;
+ }
+
+ if (!mei_me_cl_is_active(cldev->me_cl)) {
+ dev_err(&cldev->dev, "me client is not active\n");
+ ret = -ENOTTY;
+ goto out;
+ }
+
+ ret = mei_cl_bus_vtag_alloc(cldev);
+ if (ret)
+ goto out;
+
+ ret = mei_cl_connect(cl, cldev->me_cl, NULL);
+ if (ret < 0) {
+ dev_err(&cldev->dev, "cannot connect\n");
+ mei_cl_bus_vtag_free(cldev);
+ }
+
+out:
+ mutex_unlock(&bus->device_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_enable);
+
+/**
+ * mei_cldev_unregister_callbacks - internal wrapper for unregistering
+ * callbacks.
+ *
+ * @cldev: client device
+ */
+static void mei_cldev_unregister_callbacks(struct mei_cl_device *cldev)
+{
+ if (cldev->rx_cb) {
+ cancel_work_sync(&cldev->rx_work);
+ cldev->rx_cb = NULL;
+ }
+
+ if (cldev->notif_cb) {
+ cancel_work_sync(&cldev->notif_work);
+ cldev->notif_cb = NULL;
+ }
+}
+
+/**
+ * mei_cldev_disable - disable me client device
+ * disconnect form the me client
+ *
+ * @cldev: me client device
+ *
+ * Return: 0 on success and < 0 on error
+ */
+int mei_cldev_disable(struct mei_cl_device *cldev)
+{
+ struct mei_device *bus;
+ struct mei_cl *cl;
+ int err;
+
+ if (!cldev)
+ return -ENODEV;
+
+ cl = cldev->cl;
+
+ bus = cldev->bus;
+
+ mei_cldev_unregister_callbacks(cldev);
+
+ mutex_lock(&bus->device_lock);
+
+ mei_cl_bus_vtag_free(cldev);
+
+ if (!mei_cl_is_connected(cl)) {
+ dev_dbg(bus->dev, "Already disconnected\n");
+ err = 0;
+ goto out;
+ }
+
+ err = mei_cl_disconnect(cl);
+ if (err < 0)
+ dev_err(bus->dev, "Could not disconnect from the ME client\n");
+
+out:
+ /* Flush queues and remove any pending read */
+ mei_cl_flush_queues(cl, NULL);
+ mei_cl_unlink(cl);
+
+ mutex_unlock(&bus->device_lock);
+ return err;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_disable);
+
+/**
+ * mei_cl_device_find - find matching entry in the driver id table
+ *
+ * @cldev: me client device
+ * @cldrv: me client driver
+ *
+ * Return: id on success; NULL if no id is matching
+ */
+static const
+struct mei_cl_device_id *mei_cl_device_find(struct mei_cl_device *cldev,
+ struct mei_cl_driver *cldrv)
+{
+ const struct mei_cl_device_id *id;
+ const uuid_le *uuid;
+ u8 version;
+ bool match;
+
+ uuid = mei_me_cl_uuid(cldev->me_cl);
+ version = mei_me_cl_ver(cldev->me_cl);
+
+ id = cldrv->id_table;
+ while (uuid_le_cmp(NULL_UUID_LE, id->uuid)) {
+ if (!uuid_le_cmp(*uuid, id->uuid)) {
+ match = true;
+
+ if (cldev->name[0])
+ if (strncmp(cldev->name, id->name,
+ sizeof(id->name)))
+ match = false;
+
+ if (id->version != MEI_CL_VERSION_ANY)
+ if (id->version != version)
+ match = false;
+ if (match)
+ return id;
+ }
+
+ id++;
+ }
+
+ return NULL;
+}
+
+/**
+ * mei_cl_device_match - device match function
+ *
+ * @dev: device
+ * @drv: driver
+ *
+ * Return: 1 if matching device was found 0 otherwise
+ */
+static int mei_cl_device_match(struct device *dev, struct device_driver *drv)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+ struct mei_cl_driver *cldrv = to_mei_cl_driver(drv);
+ const struct mei_cl_device_id *found_id;
+
+ if (!cldev)
+ return 0;
+
+ if (!cldev->do_match)
+ return 0;
+
+ if (!cldrv || !cldrv->id_table)
+ return 0;
+
+ found_id = mei_cl_device_find(cldev, cldrv);
+ if (found_id)
+ return 1;
+
+ return 0;
+}
+
+/**
+ * mei_cl_device_probe - bus probe function
+ *
+ * @dev: device
+ *
+ * Return: 0 on success; < 0 otherwise
+ */
+static int mei_cl_device_probe(struct device *dev)
+{
+ struct mei_cl_device *cldev;
+ struct mei_cl_driver *cldrv;
+ const struct mei_cl_device_id *id;
+ int ret;
+
+ cldev = to_mei_cl_device(dev);
+ cldrv = to_mei_cl_driver(dev->driver);
+
+ if (!cldev)
+ return 0;
+
+ if (!cldrv || !cldrv->probe)
+ return -ENODEV;
+
+ id = mei_cl_device_find(cldev, cldrv);
+ if (!id)
+ return -ENODEV;
+
+ if (!mei_cl_bus_module_get(cldev)) {
+ dev_err(&cldev->dev, "get hw module failed");
+ return -ENODEV;
+ }
+
+ ret = cldrv->probe(cldev, id);
+ if (ret) {
+ mei_cl_bus_module_put(cldev);
+ return ret;
+ }
+
+ __module_get(THIS_MODULE);
+ return 0;
+}
+
+/**
+ * mei_cl_device_remove - remove device from the bus
+ *
+ * @dev: device
+ *
+ * Return: 0 on success; < 0 otherwise
+ */
+static int mei_cl_device_remove(struct device *dev)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+ struct mei_cl_driver *cldrv;
+ int ret = 0;
+
+ if (!cldev || !dev->driver)
+ return 0;
+
+ cldrv = to_mei_cl_driver(dev->driver);
+ if (cldrv->remove)
+ ret = cldrv->remove(cldev);
+
+ mei_cldev_unregister_callbacks(cldev);
+
+ mei_cl_bus_module_put(cldev);
+ module_put(THIS_MODULE);
+
+ return ret;
+}
+
+static ssize_t name_show(struct device *dev, struct device_attribute *a,
+ char *buf)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%s", cldev->name);
+}
+static DEVICE_ATTR_RO(name);
+
+static ssize_t uuid_show(struct device *dev, struct device_attribute *a,
+ char *buf)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+ const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
+
+ return sprintf(buf, "%pUl", uuid);
+}
+static DEVICE_ATTR_RO(uuid);
+
+static ssize_t version_show(struct device *dev, struct device_attribute *a,
+ char *buf)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+ u8 version = mei_me_cl_ver(cldev->me_cl);
+
+ return sprintf(buf, "%02X", version);
+}
+static DEVICE_ATTR_RO(version);
+
+static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
+ char *buf)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+ const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
+ u8 version = mei_me_cl_ver(cldev->me_cl);
+
+ return scnprintf(buf, PAGE_SIZE, "mei:%s:%pUl:%02X:",
+ cldev->name, uuid, version);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static ssize_t max_conn_show(struct device *dev, struct device_attribute *a,
+ char *buf)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+ u8 maxconn = mei_me_cl_max_conn(cldev->me_cl);
+
+ return sprintf(buf, "%d", maxconn);
+}
+static DEVICE_ATTR_RO(max_conn);
+
+static ssize_t fixed_show(struct device *dev, struct device_attribute *a,
+ char *buf)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+ u8 fixed = mei_me_cl_fixed(cldev->me_cl);
+
+ return sprintf(buf, "%d", fixed);
+}
+static DEVICE_ATTR_RO(fixed);
+
+static ssize_t vtag_show(struct device *dev, struct device_attribute *a,
+ char *buf)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+ bool vt = mei_me_cl_vt(cldev->me_cl);
+
+ return sprintf(buf, "%d", vt);
+}
+static DEVICE_ATTR_RO(vtag);
+
+static ssize_t max_len_show(struct device *dev, struct device_attribute *a,
+ char *buf)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+ u32 maxlen = mei_me_cl_max_len(cldev->me_cl);
+
+ return sprintf(buf, "%u", maxlen);
+}
+static DEVICE_ATTR_RO(max_len);
+
+static struct attribute *mei_cldev_attrs[] = {
+ &dev_attr_name.attr,
+ &dev_attr_uuid.attr,
+ &dev_attr_version.attr,
+ &dev_attr_modalias.attr,
+ &dev_attr_max_conn.attr,
+ &dev_attr_fixed.attr,
+ &dev_attr_vtag.attr,
+ &dev_attr_max_len.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(mei_cldev);
+
+/**
+ * mei_cl_device_uevent - me client bus uevent handler
+ *
+ * @dev: device
+ * @env: uevent kobject
+ *
+ * Return: 0 on success -ENOMEM on when add_uevent_var fails
+ */
+static int mei_cl_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+ const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
+ u8 version = mei_me_cl_ver(cldev->me_cl);
+
+ if (add_uevent_var(env, "MEI_CL_VERSION=%d", version))
+ return -ENOMEM;
+
+ if (add_uevent_var(env, "MEI_CL_UUID=%pUl", uuid))
+ return -ENOMEM;
+
+ if (add_uevent_var(env, "MEI_CL_NAME=%s", cldev->name))
+ return -ENOMEM;
+
+ if (add_uevent_var(env, "MODALIAS=mei:%s:%pUl:%02X:",
+ cldev->name, uuid, version))
+ return -ENOMEM;
+
+ return 0;
+}
+
+static struct bus_type mei_cl_bus_type = {
+ .name = "mei",
+ .dev_groups = mei_cldev_groups,
+ .match = mei_cl_device_match,
+ .probe = mei_cl_device_probe,
+ .remove = mei_cl_device_remove,
+ .uevent = mei_cl_device_uevent,
+};
+
+static struct mei_device *mei_dev_bus_get(struct mei_device *bus)
+{
+ if (bus)
+ get_device(bus->dev);
+
+ return bus;
+}
+
+static void mei_dev_bus_put(struct mei_device *bus)
+{
+ if (bus)
+ put_device(bus->dev);
+}
+
+static void mei_cl_bus_dev_release(struct device *dev)
+{
+ struct mei_cl_device *cldev = to_mei_cl_device(dev);
+
+ if (!cldev)
+ return;
+
+ mei_me_cl_put(cldev->me_cl);
+ mei_dev_bus_put(cldev->bus);
+ mei_cl_unlink(cldev->cl);
+ kfree(cldev->cl);
+ kfree(cldev);
+}
+
+static const struct device_type mei_cl_device_type = {
+ .release = mei_cl_bus_dev_release,
+};
+
+/**
+ * mei_cl_bus_set_name - set device name for me client device
+ * <controller>-<client device>
+ * Example: 0000:00:16.0-55213584-9a29-4916-badf-0fb7ed682aeb
+ *
+ * @cldev: me client device
+ */
+static inline void mei_cl_bus_set_name(struct mei_cl_device *cldev)
+{
+ dev_set_name(&cldev->dev, "%s-%pUl",
+ dev_name(cldev->bus->dev),
+ mei_me_cl_uuid(cldev->me_cl));
+}
+
+/**
+ * mei_cl_bus_dev_alloc - initialize and allocate mei client device
+ *
+ * @bus: mei device
+ * @me_cl: me client
+ *
+ * Return: allocated device structur or NULL on allocation failure
+ */
+static struct mei_cl_device *mei_cl_bus_dev_alloc(struct mei_device *bus,
+ struct mei_me_client *me_cl)
+{
+ struct mei_cl_device *cldev;
+ struct mei_cl *cl;
+
+ cldev = kzalloc(sizeof(*cldev), GFP_KERNEL);
+ if (!cldev)
+ return NULL;
+
+ cl = mei_cl_allocate(bus);
+ if (!cl) {
+ kfree(cldev);
+ return NULL;
+ }
+
+ device_initialize(&cldev->dev);
+ cldev->dev.parent = bus->dev;
+ cldev->dev.bus = &mei_cl_bus_type;
+ cldev->dev.type = &mei_cl_device_type;
+ cldev->bus = mei_dev_bus_get(bus);
+ cldev->me_cl = mei_me_cl_get(me_cl);
+ cldev->cl = cl;
+ mei_cl_bus_set_name(cldev);
+ cldev->is_added = 0;
+ INIT_LIST_HEAD(&cldev->bus_list);
+
+ return cldev;
+}
+
+/**
+ * mei_cl_dev_setup - setup me client device
+ * run fix up routines and set the device name
+ *
+ * @bus: mei device
+ * @cldev: me client device
+ *
+ * Return: true if the device is eligible for enumeration
+ */
+static bool mei_cl_bus_dev_setup(struct mei_device *bus,
+ struct mei_cl_device *cldev)
+{
+ cldev->do_match = 1;
+ mei_cl_bus_dev_fixup(cldev);
+
+ /* the device name can change during fix up */
+ if (cldev->do_match)
+ mei_cl_bus_set_name(cldev);
+
+ return cldev->do_match == 1;
+}
+
+/**
+ * mei_cl_bus_dev_add - add me client devices
+ *
+ * @cldev: me client device
+ *
+ * Return: 0 on success; < 0 on failre
+ */
+static int mei_cl_bus_dev_add(struct mei_cl_device *cldev)
+{
+ int ret;
+
+ dev_dbg(cldev->bus->dev, "adding %pUL:%02X\n",
+ mei_me_cl_uuid(cldev->me_cl),
+ mei_me_cl_ver(cldev->me_cl));
+ ret = device_add(&cldev->dev);
+ if (!ret)
+ cldev->is_added = 1;
+
+ return ret;
+}
+
+/**
+ * mei_cl_bus_dev_stop - stop the driver
+ *
+ * @cldev: me client device
+ */
+static void mei_cl_bus_dev_stop(struct mei_cl_device *cldev)
+{
+ if (cldev->is_added)
+ device_release_driver(&cldev->dev);
+}
+
+/**
+ * mei_cl_bus_dev_destroy - destroy me client devices object
+ *
+ * @cldev: me client device
+ *
+ * Locking: called under "dev->cl_bus_lock" lock
+ */
+static void mei_cl_bus_dev_destroy(struct mei_cl_device *cldev)
+{
+
+ WARN_ON(!mutex_is_locked(&cldev->bus->cl_bus_lock));
+
+ if (!cldev->is_added)
+ return;
+
+ device_del(&cldev->dev);
+
+ list_del_init(&cldev->bus_list);
+
+ cldev->is_added = 0;
+ put_device(&cldev->dev);
+}
+
+/**
+ * mei_cl_bus_remove_device - remove a devices form the bus
+ *
+ * @cldev: me client device
+ */
+static void mei_cl_bus_remove_device(struct mei_cl_device *cldev)
+{
+ mei_cl_bus_dev_stop(cldev);
+ mei_cl_bus_dev_destroy(cldev);
+}
+
+/**
+ * mei_cl_bus_remove_devices - remove all devices form the bus
+ *
+ * @bus: mei device
+ */
+void mei_cl_bus_remove_devices(struct mei_device *bus)
+{
+ struct mei_cl_device *cldev, *next;
+
+ mutex_lock(&bus->cl_bus_lock);
+ list_for_each_entry_safe(cldev, next, &bus->device_list, bus_list)
+ mei_cl_bus_remove_device(cldev);
+ mutex_unlock(&bus->cl_bus_lock);
+}
+
+
+/**
+ * mei_cl_bus_dev_init - allocate and initializes an mei client devices
+ * based on me client
+ *
+ * @bus: mei device
+ * @me_cl: me client
+ *
+ * Locking: called under "dev->cl_bus_lock" lock
+ */
+static void mei_cl_bus_dev_init(struct mei_device *bus,
+ struct mei_me_client *me_cl)
+{
+ struct mei_cl_device *cldev;
+
+ WARN_ON(!mutex_is_locked(&bus->cl_bus_lock));
+
+ dev_dbg(bus->dev, "initializing %pUl", mei_me_cl_uuid(me_cl));
+
+ if (me_cl->bus_added)
+ return;
+
+ cldev = mei_cl_bus_dev_alloc(bus, me_cl);
+ if (!cldev)
+ return;
+
+ me_cl->bus_added = true;
+ list_add_tail(&cldev->bus_list, &bus->device_list);
+
+}
+
+/**
+ * mei_cl_bus_rescan - scan me clients list and add create
+ * devices for eligible clients
+ *
+ * @bus: mei device
+ */
+static void mei_cl_bus_rescan(struct mei_device *bus)
+{
+ struct mei_cl_device *cldev, *n;
+ struct mei_me_client *me_cl;
+
+ mutex_lock(&bus->cl_bus_lock);
+
+ down_read(&bus->me_clients_rwsem);
+ list_for_each_entry(me_cl, &bus->me_clients, list)
+ mei_cl_bus_dev_init(bus, me_cl);
+ up_read(&bus->me_clients_rwsem);
+
+ list_for_each_entry_safe(cldev, n, &bus->device_list, bus_list) {
+
+ if (!mei_me_cl_is_active(cldev->me_cl)) {
+ mei_cl_bus_remove_device(cldev);
+ continue;
+ }
+
+ if (cldev->is_added)
+ continue;
+
+ if (mei_cl_bus_dev_setup(bus, cldev))
+ mei_cl_bus_dev_add(cldev);
+ else {
+ list_del_init(&cldev->bus_list);
+ put_device(&cldev->dev);
+ }
+ }
+ mutex_unlock(&bus->cl_bus_lock);
+
+ dev_dbg(bus->dev, "rescan end");
+}
+
+void mei_cl_bus_rescan_work(struct work_struct *work)
+{
+ struct mei_device *bus =
+ container_of(work, struct mei_device, bus_rescan_work);
+
+ mei_cl_bus_rescan(bus);
+}
+
+int __mei_cldev_driver_register(struct mei_cl_driver *cldrv,
+ struct module *owner)
+{
+ int err;
+
+ cldrv->driver.name = cldrv->name;
+ cldrv->driver.owner = owner;
+ cldrv->driver.bus = &mei_cl_bus_type;
+
+ err = driver_register(&cldrv->driver);
+ if (err)
+ return err;
+
+ pr_debug("mei: driver [%s] registered\n", cldrv->driver.name);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(__mei_cldev_driver_register);
+
+void mei_cldev_driver_unregister(struct mei_cl_driver *cldrv)
+{
+ driver_unregister(&cldrv->driver);
+
+ pr_debug("mei: driver [%s] unregistered\n", cldrv->driver.name);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_driver_unregister);
+
+
+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);
+}