From 3e8332952dedd2c17bb497e3909e3b6fbac10ce7 Mon Sep 17 00:00:00 2001 From: Samuel Ortiz Date: Wed, 27 Mar 2013 17:29:55 +0200 Subject: [PATCH] mei: bus: Initial implementation for I/O routines Signed-off-by: Samuel Ortiz Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman --- drivers/misc/mei/bus.c | 226 +++++++++++++++++++++++++++++++++++++ drivers/misc/mei/mei_dev.h | 30 +++++ include/linux/mei_cl_bus.h | 11 ++ 3 files changed, 267 insertions(+) diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c index d16b3c3e1b38..16c7fff50549 100644 --- a/drivers/misc/mei/bus.c +++ b/drivers/misc/mei/bus.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include @@ -25,6 +26,8 @@ #include #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); diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h index 7abb705ddf3f..cde5687039f3 100644 --- a/drivers/misc/mei/mei_dev.h +++ b/drivers/misc/mei/mei_dev.h @@ -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; }; diff --git a/include/linux/mei_cl_bus.h b/include/linux/mei_cl_bus.h index ba2aa3b66f30..d9958c3960a2 100644 --- a/include/linux/mei_cl_bus.h +++ b/include/linux/mei_cl_bus.h @@ -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 */ -- GitLab