caif-hsi: Added recovery check of CA wake status.

Added recovery check of CA wake status in case of wake up timeout.
Added check of CA wake status in case of wake down timeout.

Signed-off-by: Sjur Brændeland <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/caif/caif_hsi.c

···
 		/* It happenes when wakeup is requested by
 		 * both ends at the same time. */
 		clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
+		clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
 		return;
 	}
 
···
 							&cfhsi->bits), ret);
 	if (unlikely(ret < 0)) {
 		/* Interrupted by signal. */
-		dev_info(&cfhsi->ndev->dev, "%s: Signalled: %ld.\n",
+		dev_err(&cfhsi->ndev->dev, "%s: Signalled: %ld.\n",
 			__func__, ret);
+
 		clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
 		cfhsi->dev->cfhsi_wake_down(cfhsi->dev);
 		return;
 	} else if (!ret) {
+		bool ca_wake = false;
+		size_t fifo_occupancy = 0;
+
 		/* Wakeup timeout */
 		dev_err(&cfhsi->ndev->dev, "%s: Timeout.\n",
 			__func__);
+
+		/* Check FIFO to check if modem has sent something. */
+		WARN_ON(cfhsi->dev->cfhsi_fifo_occupancy(cfhsi->dev,
+					&fifo_occupancy));
+
+		dev_err(&cfhsi->ndev->dev, "%s: Bytes in FIFO: %u.\n",
+				__func__, (unsigned) fifo_occupancy);
+
+		/* Check if we misssed the interrupt. */
+		WARN_ON(cfhsi->dev->cfhsi_get_peer_wake(cfhsi->dev,
+							&ca_wake));
+
+		if (ca_wake) {
+			dev_err(&cfhsi->ndev->dev, "%s: CA Wake missed !.\n",
+				__func__);
+
+			/* Clear the CFHSI_WAKE_UP_ACK bit to prevent race. */
+			clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
+
+			/* Continue execution. */
+			goto wake_ack;
+		}
+
 		clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
 		cfhsi->dev->cfhsi_wake_down(cfhsi->dev);
 		return;
 	}
+wake_ack:
 	dev_dbg(&cfhsi->ndev->dev, "%s: Woken.\n",
 		__func__);
 
···
 							&cfhsi->bits), ret);
 	if (ret < 0) {
 		/* Interrupted by signal. */
-		dev_info(&cfhsi->ndev->dev, "%s: Signalled: %ld.\n",
+		dev_err(&cfhsi->ndev->dev, "%s: Signalled: %ld.\n",
 			__func__, ret);
 		return;
 	} else if (!ret) {
+		bool ca_wake = true;
+
 		/* Timeout */
 		dev_err(&cfhsi->ndev->dev, "%s: Timeout.\n", __func__);
+
+		/* Check if we misssed the interrupt. */
+		WARN_ON(cfhsi->dev->cfhsi_get_peer_wake(cfhsi->dev,
+							&ca_wake));
+		if (!ca_wake)
+			dev_err(&cfhsi->ndev->dev, "%s: CA Wake missed !.\n",
+				__func__);
 	}
 
 	/* Check FIFO occupancy. */

include/net/caif/caif_hsi.h

···
 	int (*cfhsi_rx) (u8 *ptr, int len, struct cfhsi_dev *dev);
 	int (*cfhsi_wake_up) (struct cfhsi_dev *dev);
 	int (*cfhsi_wake_down) (struct cfhsi_dev *dev);
+	int (*cfhsi_get_peer_wake) (struct cfhsi_dev *dev, bool *status);
 	int (*cfhsi_fifo_occupancy)(struct cfhsi_dev *dev, size_t *occupancy);
 	int (*cfhsi_rx_cancel)(struct cfhsi_dev *dev);
 	struct cfhsi_drv *drv;