mei: disconnect on connection request timeout

For the FW with  HBM version >= 2.0 we don't need to reset the whole
device in case of a particular client failing to connect, it is enough
to send disconnect a request to bring the device to the stable state.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index 9dacea7a9a60a24f98bfb5cddf952e55649f10ff..40285e02b6122435545185aee04bed3929a6ef13 100644 (file)
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -836,44 +836,24 @@ int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
        return ret;
 }
 
-
-
 /**
- * mei_cl_disconnect - disconnect host client from the me one
+ * __mei_cl_disconnect - disconnect host client from the me one
+ *     internal function runtime pm has to be already acquired
  *
  * @cl: host client
  *
- * Locking: called under "dev->device_lock" lock
- *
  * Return: 0 on success, <0 on failure.
  */
-int mei_cl_disconnect(struct mei_cl *cl)
+static int __mei_cl_disconnect(struct mei_cl *cl)
 {
        struct mei_device *dev;
        struct mei_cl_cb *cb;
        int rets;
 
-       if (WARN_ON(!cl || !cl->dev))
-               return -ENODEV;
-
        dev = cl->dev;
 
-       cl_dbg(dev, cl, "disconnecting");
-
-       if (!mei_cl_is_connected(cl))
-               return 0;
-
-       if (mei_cl_is_fixed_address(cl)) {
-               mei_cl_set_disconnected(cl);
-               return 0;
-       }
-
-       rets = pm_runtime_get(dev->dev);
-       if (rets < 0 && rets != -EINPROGRESS) {
-               pm_runtime_put_noidle(dev->dev);
-               cl_err(dev, cl, "rpm: get failed %d\n", rets);
-               return rets;
-       }
+       if (WARN_ON(!pm_runtime_active(dev->dev)))
+               return -EFAULT;
 
        cl->state = MEI_FILE_DISCONNECTING;
 
@@ -910,11 +890,52 @@ out:
        if (!rets)
                cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
 
+       mei_io_cb_free(cb);
+       return rets;
+}
+
+/**
+ * mei_cl_disconnect - disconnect host client from the me one
+ *
+ * @cl: host client
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_cl_disconnect(struct mei_cl *cl)
+{
+       struct mei_device *dev;
+       int rets;
+
+       if (WARN_ON(!cl || !cl->dev))
+               return -ENODEV;
+
+       dev = cl->dev;
+
+       cl_dbg(dev, cl, "disconnecting");
+
+       if (!mei_cl_is_connected(cl))
+               return 0;
+
+       if (mei_cl_is_fixed_address(cl)) {
+               mei_cl_set_disconnected(cl);
+               return 0;
+       }
+
+       rets = pm_runtime_get(dev->dev);
+       if (rets < 0 && rets != -EINPROGRESS) {
+               pm_runtime_put_noidle(dev->dev);
+               cl_err(dev, cl, "rpm: get failed %d\n", rets);
+               return rets;
+       }
+
+       rets = __mei_cl_disconnect(cl);
+
        cl_dbg(dev, cl, "rpm: autosuspend\n");
        pm_runtime_mark_last_busy(dev->dev);
        pm_runtime_put_autosuspend(dev->dev);
 
-       mei_io_cb_free(cb);
        return rets;
 }
 
@@ -1059,11 +1080,23 @@ int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
        mutex_unlock(&dev->device_lock);
        wait_event_timeout(cl->wait,
                        (cl->state == MEI_FILE_CONNECTED ||
+                        cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
                         cl->state == MEI_FILE_DISCONNECT_REPLY),
                        mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
        mutex_lock(&dev->device_lock);
 
        if (!mei_cl_is_connected(cl)) {
+               if (cl->state == MEI_FILE_DISCONNECT_REQUIRED) {
+                       mei_io_list_flush(&dev->ctrl_rd_list, cl);
+                       mei_io_list_flush(&dev->ctrl_wr_list, cl);
+                        /* ignore disconnect return valuue;
+                         * in case of failure reset will be invoked
+                         */
+                       __mei_cl_disconnect(cl);
+                       rets = -EFAULT;
+                       goto out;
+               }
+
                /* timeout or something went really wrong */
                if (!cl->status)
                        cl->status = -EFAULT;

diff --git a/drivers/misc/mei/debugfs.c b/drivers/misc/mei/debugfs.c
index a65a1e6f386fc85bab97a530f5876d608278b9ef..e39cfe6bc5bced955c93fafed00bfaf944b34b70 100644 (file)
--- a/drivers/misc/mei/debugfs.c
+++ b/drivers/misc/mei/debugfs.c
@@ -156,6 +156,8 @@ static ssize_t mei_dbgfs_read_devstate(struct file *fp, char __user *ubuf,
                                 dev->hbm_f_pg_supported);
                pos += scnprintf(buf + pos, bufsz - pos, "\tDC: %01d\n",
                                 dev->hbm_f_dc_supported);
+               pos += scnprintf(buf + pos, bufsz - pos, "\tDOT: %01d\n",
+                                dev->hbm_f_dot_supported);
        }
 
        pos += scnprintf(buf + pos, bufsz - pos, "pg:  %s, %s\n",

diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c
index d4dba639db3712af082266fa36edfc6a9a6394c0..07a8ea8362a3e46e92cc726bfad7300d15d51bd5 100644 (file)
--- a/drivers/misc/mei/hbm.c
+++ b/drivers/misc/mei/hbm.c
@@ -774,6 +774,10 @@ static void mei_hbm_config_features(struct mei_device *dev)
 
        if (dev->version.major_version >= HBM_MAJOR_VERSION_DC)
                dev->hbm_f_dc_supported = 1;
+
+       /* disconnect on connect timeout instead of link reset */
+       if (dev->version.major_version >= HBM_MAJOR_VERSION_DOT)
+               dev->hbm_f_dot_supported = 1;
 }
 
 /**

diff --git a/drivers/misc/mei/hw.h b/drivers/misc/mei/hw.h
index 815f40a604b923da610f870698357424534b4b7a..e961be392fae0f1a956358c505b8ba347f89acfc 100644 (file)
--- a/drivers/misc/mei/hw.h
+++ b/drivers/misc/mei/hw.h
@@ -52,6 +52,12 @@
 #define HBM_MINOR_VERSION_DC               0
 #define HBM_MAJOR_VERSION_DC               2
 
+/*
+ * MEI version with disconnect on connection timeout support
+ */
+#define HBM_MINOR_VERSION_DOT              0
+#define HBM_MAJOR_VERSION_DOT              2
+
 /* Host bus message command opcode */
 #define MEI_HBM_CMD_OP_MSK                  0x7f
 /* Host bus message command RESPONSE */

diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index 3f3405269c39d537634e2895ae0ecf64ab0b1775..89d8e13040774569e94aa2e4911643f33b927520 100644 (file)
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -424,6 +424,24 @@ int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
 EXPORT_SYMBOL_GPL(mei_irq_write_handler);
 
 
+/**
+ * mei_connect_timeout  - connect/disconnect timeouts
+ *
+ * @cl: host client
+ */
+static void mei_connect_timeout(struct mei_cl *cl)
+{
+       struct mei_device *dev = cl->dev;
+
+       if (cl->state == MEI_FILE_CONNECTING) {
+               if (dev->hbm_f_dot_supported) {
+                       cl->state = MEI_FILE_DISCONNECT_REQUIRED;
+                       wake_up(&cl->wait);
+                       return;
+               }
+       }
+       mei_reset(dev);
+}
 
 /**
  * mei_timer - timer function.
@@ -464,7 +482,7 @@ void mei_timer(struct work_struct *work)
                if (cl->timer_count) {
                        if (--cl->timer_count == 0) {
                                dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
-                               mei_reset(dev);
+                               mei_connect_timeout(cl);
                                goto out;
                        }
                }

diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
index 33823f4a1cf223d33de5728c260d36c9c4d45834..8bd46cd95b7a80cdaec332599fee29366ffa260a 100644 (file)
--- a/drivers/misc/mei/mei_dev.h
+++ b/drivers/misc/mei/mei_dev.h
@@ -89,6 +89,7 @@ enum file_state {
        MEI_FILE_CONNECTED,
        MEI_FILE_DISCONNECTING,
        MEI_FILE_DISCONNECT_REPLY,
+       MEI_FILE_DISCONNECT_REQUIRED,
        MEI_FILE_DISCONNECTED,
 };
 
@@ -407,8 +408,9 @@ const char *mei_pg_state_str(enum mei_pg_state state);
  * @wr_msg      : the buffer for hbm control messages
  *
  * @version     : HBM protocol version in use
- * @hbm_f_pg_supported : hbm feature pgi protocol
- * @hbm_f_dc_supported : hbm feature dynamic clients
+ * @hbm_f_pg_supported  : hbm feature pgi protocol
+ * @hbm_f_dc_supported  : hbm feature dynamic clients
+ * @hbm_f_dot_supported : hbm feature disconnect on timeout
  *
  * @me_clients_rwsem: rw lock over me_clients list
  * @me_clients  : list of FW clients
@@ -503,6 +505,7 @@ struct mei_device {
        struct hbm_version version;
        unsigned int hbm_f_pg_supported:1;
        unsigned int hbm_f_dc_supported:1;
+       unsigned int hbm_f_dot_supported:1;
 
        struct rw_semaphore me_clients_rwsem;
        struct list_head me_clients;