1 files changed, 182 insertions, 96 deletions

diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c
index f7f3abbe12b6..cdd31c2a2a2b 100644
--- a/drivers/misc/mei/init.c
+++ b/drivers/misc/mei/init.c
@@ -43,41 +43,119 @@ const char *mei_dev_state_str(int state)
 #undef MEI_DEV_STATE
 }
 
-void mei_device_init(struct mei_device *dev)
-{
-	/* setup our list array */
-	INIT_LIST_HEAD(&dev->file_list);
-	INIT_LIST_HEAD(&dev->device_list);
-	mutex_init(&dev->device_lock);
-	init_waitqueue_head(&dev->wait_hw_ready);
-	init_waitqueue_head(&dev->wait_recvd_msg);
-	init_waitqueue_head(&dev->wait_stop_wd);
-	dev->dev_state = MEI_DEV_INITIALIZING;
 
-	mei_io_list_init(&dev->read_list);
-	mei_io_list_init(&dev->write_list);
-	mei_io_list_init(&dev->write_waiting_list);
-	mei_io_list_init(&dev->ctrl_wr_list);
-	mei_io_list_init(&dev->ctrl_rd_list);
+/**
+ * mei_cancel_work. Cancel mei background jobs
+ *
+ * @dev: the device structure
+ *
+ * returns 0 on success or < 0 if the reset hasn't succeeded
+ */
+void mei_cancel_work(struct mei_device *dev)
+{
+	cancel_work_sync(&dev->init_work);
+	cancel_work_sync(&dev->reset_work);
 
-	INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
-	INIT_WORK(&dev->init_work, mei_host_client_init);
+	cancel_delayed_work(&dev->timer_work);
+}
+EXPORT_SYMBOL_GPL(mei_cancel_work);
 
-	INIT_LIST_HEAD(&dev->wd_cl.link);
-	INIT_LIST_HEAD(&dev->iamthif_cl.link);
-	mei_io_list_init(&dev->amthif_cmd_list);
-	mei_io_list_init(&dev->amthif_rd_complete_list);
+/**
+ * mei_reset - resets host and fw.
+ *
+ * @dev: the device structure
+ */
+int mei_reset(struct mei_device *dev)
+{
+	enum mei_dev_state state = dev->dev_state;
+	bool interrupts_enabled;
+	int ret;
 
-	bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
-	dev->open_handle_count = 0;
+	if (state != MEI_DEV_INITIALIZING &&
+	    state != MEI_DEV_DISABLED &&
+	    state != MEI_DEV_POWER_DOWN &&
+	    state != MEI_DEV_POWER_UP)
+		dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
+			 mei_dev_state_str(state));
 
-	/*
-	 * Reserving the first client ID
-	 * 0: Reserved for MEI Bus Message communications
+	/* we're already in reset, cancel the init timer
+	 * if the reset was called due the hbm protocol error
+	 * we need to call it before hw start
+	 * so the hbm watchdog won't kick in
 	 */
-	bitmap_set(dev->host_clients_map, 0, 1);
+	mei_hbm_idle(dev);
+
+	/* enter reset flow */
+	interrupts_enabled = state != MEI_DEV_POWER_DOWN;
+	dev->dev_state = MEI_DEV_RESETTING;
+
+	dev->reset_count++;
+	if (dev->reset_count > MEI_MAX_CONSEC_RESET) {
+		dev_err(&dev->pdev->dev, "reset: reached maximal consecutive resets: disabling the device\n");
+		dev->dev_state = MEI_DEV_DISABLED;
+		return -ENODEV;
+	}
+
+	ret = mei_hw_reset(dev, interrupts_enabled);
+	/* fall through and remove the sw state even if hw reset has failed */
+
+	/* no need to clean up software state in case of power up */
+	if (state != MEI_DEV_INITIALIZING &&
+	    state != MEI_DEV_POWER_UP) {
+
+		/* remove all waiting requests */
+		mei_cl_all_write_clear(dev);
+
+		mei_cl_all_disconnect(dev);
+
+		/* wake up all readers and writers so they can be interrupted */
+		mei_cl_all_wakeup(dev);
+
+		/* remove entry if already in list */
+		dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
+		mei_cl_unlink(&dev->wd_cl);
+		mei_cl_unlink(&dev->iamthif_cl);
+		mei_amthif_reset_params(dev);
+		memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
+	}
+
+
+	dev->me_clients_num = 0;
+	dev->rd_msg_hdr = 0;
+	dev->wd_pending = false;
+
+	if (ret) {
+		dev_err(&dev->pdev->dev, "hw_reset failed ret = %d\n", ret);
+		dev->dev_state = MEI_DEV_DISABLED;
+		return ret;
+	}
+
+	if (state == MEI_DEV_POWER_DOWN) {
+		dev_dbg(&dev->pdev->dev, "powering down: end of reset\n");
+		dev->dev_state = MEI_DEV_DISABLED;
+		return 0;
+	}
+
+	ret = mei_hw_start(dev);
+	if (ret) {
+		dev_err(&dev->pdev->dev, "hw_start failed ret = %d\n", ret);
+		dev->dev_state = MEI_DEV_DISABLED;
+		return ret;
+	}
+
+	dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n");
+
+	dev->dev_state = MEI_DEV_INIT_CLIENTS;
+	ret = mei_hbm_start_req(dev);
+	if (ret) {
+		dev_err(&dev->pdev->dev, "hbm_start failed ret = %d\n", ret);
+		dev->dev_state = MEI_DEV_DISABLED;
+		return ret;
+	}
+
+	return 0;
 }
-EXPORT_SYMBOL_GPL(mei_device_init);
+EXPORT_SYMBOL_GPL(mei_reset);
 
 /**
  * mei_start - initializes host and fw to start work.
@@ -90,14 +168,21 @@ int mei_start(struct mei_device *dev)
 {
 	mutex_lock(&dev->device_lock);
 
-	/* acknowledge interrupt and stop interupts */
+	/* acknowledge interrupt and stop interrupts */
 	mei_clear_interrupts(dev);
 
 	mei_hw_config(dev);
 
 	dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
 
-	mei_reset(dev, 1);
+	dev->dev_state = MEI_DEV_INITIALIZING;
+	dev->reset_count = 0;
+	mei_reset(dev);
+
+	if (dev->dev_state == MEI_DEV_DISABLED) {
+		dev_err(&dev->pdev->dev, "reset failed");
+		goto err;
+	}
 
 	if (mei_hbm_start_wait(dev)) {
 		dev_err(&dev->pdev->dev, "HBM haven't started");
@@ -132,101 +217,64 @@ err:
 EXPORT_SYMBOL_GPL(mei_start);
 
 /**
- * mei_reset - resets host and fw.
+ * mei_restart - restart device after suspend
  *
  * @dev: the device structure
- * @interrupts_enabled: if interrupt should be enabled after reset.
+ *
+ * returns 0 on success or -ENODEV if the restart hasn't succeeded
  */
-void mei_reset(struct mei_device *dev, int interrupts_enabled)
+int mei_restart(struct mei_device *dev)
 {
-	bool unexpected;
-	int ret;
-
-	unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
-			dev->dev_state != MEI_DEV_DISABLED &&
-			dev->dev_state != MEI_DEV_POWER_DOWN &&
-			dev->dev_state != MEI_DEV_POWER_UP);
+	int err;
 
-	if (unexpected)
-		dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
-			 mei_dev_state_str(dev->dev_state));
-
-	ret = mei_hw_reset(dev, interrupts_enabled);
-	if (ret) {
-		dev_err(&dev->pdev->dev, "hw reset failed disabling the device\n");
-		interrupts_enabled = false;
-		dev->dev_state = MEI_DEV_DISABLED;
-	}
-
-	dev->hbm_state = MEI_HBM_IDLE;
+	mutex_lock(&dev->device_lock);
 
-	if (dev->dev_state != MEI_DEV_INITIALIZING &&
-	    dev->dev_state != MEI_DEV_POWER_UP) {
-		if (dev->dev_state != MEI_DEV_DISABLED &&
-		    dev->dev_state != MEI_DEV_POWER_DOWN)
-			dev->dev_state = MEI_DEV_RESETTING;
+	mei_clear_interrupts(dev);
 
-		/* remove all waiting requests */
-		mei_cl_all_write_clear(dev);
+	dev->dev_state = MEI_DEV_POWER_UP;
+	dev->reset_count = 0;
 
-		mei_cl_all_disconnect(dev);
+	err = mei_reset(dev);
 
-		/* wake up all readings so they can be interrupted */
-		mei_cl_all_wakeup(dev);
-
-		/* remove entry if already in list */
-		dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
-		mei_cl_unlink(&dev->wd_cl);
-		mei_cl_unlink(&dev->iamthif_cl);
-		mei_amthif_reset_params(dev);
-		memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
-	}
+	mutex_unlock(&dev->device_lock);
 
-	/* we're already in reset, cancel the init timer */
-	dev->init_clients_timer = 0;
+	if (err || dev->dev_state == MEI_DEV_DISABLED)
+		return -ENODEV;
 
-	dev->me_clients_num = 0;
-	dev->rd_msg_hdr = 0;
-	dev->wd_pending = false;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_restart);
 
-	if (!interrupts_enabled) {
-		dev_dbg(&dev->pdev->dev, "intr not enabled end of reset\n");
-		return;
-	}
 
-	ret = mei_hw_start(dev);
-	if (ret) {
-		dev_err(&dev->pdev->dev, "hw_start failed disabling the device\n");
-		dev->dev_state = MEI_DEV_DISABLED;
-		return;
-	}
+static void mei_reset_work(struct work_struct *work)
+{
+	struct mei_device *dev =
+		container_of(work, struct mei_device,  reset_work);
 
-	dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n");
-	/* link is established * start sending messages.  */
+	mutex_lock(&dev->device_lock);
 
-	dev->dev_state = MEI_DEV_INIT_CLIENTS;
+	mei_reset(dev);
 
-	mei_hbm_start_req(dev);
+	mutex_unlock(&dev->device_lock);
 
+	if (dev->dev_state == MEI_DEV_DISABLED)
+		dev_err(&dev->pdev->dev, "reset failed");
 }
-EXPORT_SYMBOL_GPL(mei_reset);
 
 void mei_stop(struct mei_device *dev)
 {
 	dev_dbg(&dev->pdev->dev, "stopping the device.\n");
 
-	flush_scheduled_work();
+	mei_cancel_work(dev);
 
-	mutex_lock(&dev->device_lock);
+	mei_nfc_host_exit(dev);
 
-	cancel_delayed_work(&dev->timer_work);
+	mutex_lock(&dev->device_lock);
 
 	mei_wd_stop(dev);
 
-	mei_nfc_host_exit();
-
 	dev->dev_state = MEI_DEV_POWER_DOWN;
-	mei_reset(dev, 0);
+	mei_reset(dev);
 
 	mutex_unlock(&dev->device_lock);
 
@@ -236,3 +284,41 @@ EXPORT_SYMBOL_GPL(mei_stop);
 
 
 
+void mei_device_init(struct mei_device *dev)
+{
+	/* setup our list array */
+	INIT_LIST_HEAD(&dev->file_list);
+	INIT_LIST_HEAD(&dev->device_list);
+	mutex_init(&dev->device_lock);
+	init_waitqueue_head(&dev->wait_hw_ready);
+	init_waitqueue_head(&dev->wait_recvd_msg);
+	init_waitqueue_head(&dev->wait_stop_wd);
+	dev->dev_state = MEI_DEV_INITIALIZING;
+	dev->reset_count = 0;
+
+	mei_io_list_init(&dev->read_list);
+	mei_io_list_init(&dev->write_list);
+	mei_io_list_init(&dev->write_waiting_list);
+	mei_io_list_init(&dev->ctrl_wr_list);
+	mei_io_list_init(&dev->ctrl_rd_list);
+
+	INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
+	INIT_WORK(&dev->init_work, mei_host_client_init);
+	INIT_WORK(&dev->reset_work, mei_reset_work);
+
+	INIT_LIST_HEAD(&dev->wd_cl.link);
+	INIT_LIST_HEAD(&dev->iamthif_cl.link);
+	mei_io_list_init(&dev->amthif_cmd_list);
+	mei_io_list_init(&dev->amthif_rd_complete_list);
+
+	bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
+	dev->open_handle_count = 0;
+
+	/*
+	 * Reserving the first client ID
+	 * 0: Reserved for MEI Bus Message communications
+	 */
+	bitmap_set(dev->host_clients_map, 0, 1);
+}
+EXPORT_SYMBOL_GPL(mei_device_init);
+