mei: bus: Initial implementation for I/O routines

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>
This commit is contained in:
Samuel Ortiz 2013-03-27 17:29:55 +02:00 committed by Greg Kroah-Hartman
parent 333e4ee078
commit 3e8332952d
3 changed files with 267 additions and 0 deletions

View File

@ -16,6 +16,7 @@
#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>
@ -25,6 +26,8 @@
#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)
@ -81,6 +84,11 @@ static int mei_cl_device_remove(struct device *dev)
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;
@ -196,3 +204,221 @@ void mei_cl_driver_unregister(struct mei_cl_driver *driver)
pr_debug("mei: driver [%s] unregistered\n", driver->driver.name);
}
EXPORT_SYMBOL_GPL(mei_cl_driver_unregister);
int __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length)
{
struct mei_device *dev;
struct mei_msg_hdr mei_hdr;
struct mei_cl_cb *cb;
int me_cl_id, err;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
if (cl->state != MEI_FILE_CONNECTED)
return -ENODEV;
cb = mei_io_cb_init(cl, NULL);
if (!cb)
return -ENOMEM;
err = mei_io_cb_alloc_req_buf(cb, length);
if (err < 0) {
mei_io_cb_free(cb);
return err;
}
memcpy(cb->request_buffer.data, buf, length);
cb->fop_type = MEI_FOP_WRITE;
dev = cl->dev;
mutex_lock(&dev->device_lock);
/* Check if we have an ME client device */
me_cl_id = mei_me_cl_by_id(dev, cl->me_client_id);
if (me_cl_id == dev->me_clients_num) {
err = -ENODEV;
goto out_err;
}
if (length > dev->me_clients[me_cl_id].props.max_msg_length) {
err = -EINVAL;
goto out_err;
}
err = mei_cl_flow_ctrl_creds(cl);
if (err < 0)
goto out_err;
/* Host buffer is not ready, we queue the request */
if (err == 0 || !dev->hbuf_is_ready) {
cb->buf_idx = 0;
mei_hdr.msg_complete = 0;
cl->writing_state = MEI_WRITING;
list_add_tail(&cb->list, &dev->write_list.list);
mutex_unlock(&dev->device_lock);
return length;
}
dev->hbuf_is_ready = false;
/* Check for a maximum length */
if (length > mei_hbuf_max_len(dev)) {
mei_hdr.length = mei_hbuf_max_len(dev);
mei_hdr.msg_complete = 0;
} else {
mei_hdr.length = length;
mei_hdr.msg_complete = 1;
}
mei_hdr.host_addr = cl->host_client_id;
mei_hdr.me_addr = cl->me_client_id;
mei_hdr.reserved = 0;
if (mei_write_message(dev, &mei_hdr, buf)) {
err = -EIO;
goto out_err;
}
cl->writing_state = MEI_WRITING;
cb->buf_idx = mei_hdr.length;
if (!mei_hdr.msg_complete) {
list_add_tail(&cb->list, &dev->write_list.list);
} else {
if (mei_cl_flow_ctrl_reduce(cl)) {
err = -EIO;
goto out_err;
}
list_add_tail(&cb->list, &dev->write_waiting_list.list);
}
mutex_unlock(&dev->device_lock);
return mei_hdr.length;
out_err:
mutex_unlock(&dev->device_lock);
mei_io_cb_free(cb);
return err;
}
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;
}
int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length)
{
struct mei_cl *cl = NULL;
/* TODO: hook between mei_bus_client and mei_cl */
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 = NULL;
/* TODO: hook between mei_bus_client and mei_cl */
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);

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@ -268,6 +268,25 @@ 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_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
* This structure allows ME host clients to implement technology
* specific transport layers.
*
* @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 {
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 device handle
* An mei_cl_device pointer is returned from mei_add_device()
@ -278,6 +297,10 @@ void mei_cl_remove_device(struct mei_cl_device *device);
* @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 {
@ -285,6 +308,13 @@ struct mei_cl_device {
struct mei_cl *cl;
const struct mei_cl_transport_ops *ops;
struct work_struct event_work;
mei_cl_event_cb_t event_cb;
void *event_context;
unsigned long events;
void *priv_data;
};

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@ -24,4 +24,15 @@ int __mei_cl_driver_register(struct mei_cl_driver *driver,
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
#endif /* _LINUX_MEI_CL_BUS_H */