From edb4a79b1ef031fbd7f84c66e75e1d906397949f Mon Sep 17 00:00:00 2001
From: Karthik Poosa <kpoosa2@codeaurora.org>
Date: Thu, 5 Mar 2020 19:42:44 +0530
Subject: [PATCH] NFC: Add timeout when waiting for responses in probe

Add timeout of MAX_IBI_WAIT_TIME(ms) when waiting for responses in probe.
Without this timeout, device boot can be stuck if there is no response
for NFC commands, as nfc probe waiting for responses indefinitely.

Change-Id: Iecfb318d72a8d80eba8fa7977007125fa372eaa5
Signed-off-by: Karthik Poosa <kpoosa2@codeaurora.org>
---
 drivers/nfc/qti/nfc_i3c_drv.c | 28 +++++++++++++++++++++++-----
 drivers/nfc/qti/nfc_i3c_drv.h |  4 ++++
 2 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/drivers/nfc/qti/nfc_i3c_drv.c b/drivers/nfc/qti/nfc_i3c_drv.c
index d72e5ad4ab8f..b4fb9e9ac1dc 100644
--- a/drivers/nfc/qti/nfc_i3c_drv.c
+++ b/drivers/nfc/qti/nfc_i3c_drv.c
@@ -199,11 +199,28 @@ int i3c_nci_kbuf_retrieve(struct nfc_dev *dev, char *buf,
 			break;
 
 		reinit_completion(&i3c_dev->read_cplt);
-		ret = wait_for_completion_interruptible(&i3c_dev->read_cplt);
-		if (ret != 0) {
-			pr_err("didn't get completion, interrupted!! ret %d\n",
-			       ret);
-			return ret;
+		/*
+		 * During probe if there is no response for NCI commands,
+		 * probe shouldn't be blocked, that is why timeout is added.
+		 */
+
+		if (i3c_dev->is_probe_done) {
+			ret = wait_for_completion_interruptible(
+							&i3c_dev->read_cplt);
+			if (ret != 0) {
+				pr_err("nfc completion interrupted! ret %d\n",
+							ret);
+				return ret;
+			}
+		} else {
+			ret = wait_for_completion_interruptible_timeout(
+					&i3c_dev->read_cplt,
+					msecs_to_jiffies(MAX_IBI_WAIT_TIME));
+			if (ret <= 0) {
+				pr_err("nfc completion timedout ret %d\n",
+							ret);
+				return ret;
+			}
 		}
 	} while (available_size < requested_size);
 
@@ -675,6 +692,7 @@ int nfc_i3c_dev_probe(struct i3c_device *device)
 
 	atomic_set(&nfc_dev->i3c_dev.pm_state, PM_STATE_NORMAL);
 	device_init_wakeup(&device->dev, true);
+	nfc_dev->i3c_dev.is_probe_done = true;
 
 	pr_info("%s success\n", __func__);
 
diff --git a/drivers/nfc/qti/nfc_i3c_drv.h b/drivers/nfc/qti/nfc_i3c_drv.h
index 78be4a7ff3be..7ef3dfda2990 100644
--- a/drivers/nfc/qti/nfc_i3c_drv.h
+++ b/drivers/nfc/qti/nfc_i3c_drv.h
@@ -41,6 +41,8 @@
 // I3C WorkQueue name
 #define NFC_I3C_WORKQUEUE		"nfc_i3c_workq"
 
+/* Time(in ms) to wait for NCI packet respones */
+#define MAX_IBI_WAIT_TIME		(2000)
 struct nfc_dev;
 
 /**
@@ -72,6 +74,7 @@ struct nci_buf {
  * @ibi_enabled:      IBI enabled or not.
  * @pm_state:         PM state of NFC I3C device.
  * @nfc_read_direct   Do NFC read bypassing the read buffer.
+ * @is_probe_done     Is NFC I3C probe completed.
  */
 struct i3c_dev {
 	struct i3c_device *device;
@@ -87,6 +90,7 @@ struct i3c_dev {
 	atomic_t pm_state;
 	int (*nfc_read_direct)(struct nfc_dev *dev,
 					char *buf, size_t count);
+	bool is_probe_done;
 };
 
 int nfc_i3c_dev_probe(struct i3c_device *device);