Date:   Thu, 16 Mar 2023 17:56:02 +0500
From:   Khadija Kamran <kamrankhadijadj@gmail.com>
To:     outreachy@lists.linux.dev
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: [PATCH v5] staging: axis-fifo: initialize timeouts in probe only
Message-ID: <ZBMR4s8xyHGqMm72@khadija-virtual-machine>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Precedence: bulk

Module parameter, read_timeout, can only be set at the loading time. As
it can only be modified once, initialize read_timeout once in the probe
function.

As a result, only use read_timeout as the last argument in
wait_event_interruptible_timeout() call.

Convert datatpe of read_timeout from 'int' to 'long int' because
implicit conversion of 'long int' to 'int' in statement 'read_timeout =
MAX_SCHEDULE_TIMEOUT' results in an overflow warning.

Perform same steps formodule parameter, write_timeout.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khadija Kamran <kamrankhadijadj@gmail.com>
---

Changes in v5:
 - Convert timeout's datatype from int to long.
Changes in v4:
 - Initialize timeouts once as suggested by Greg; this automatically
   fixes the indentation problems.
 - Change the subject and description.
Changes in v3:
 - Fix grammatical mistakes
 - Do not change the second argument's indentation in split lines 
Changes in v2:
 - Instead of matching alignment to open parenthesis, align second and
   the last argument instead.
 - Change the subject to 'remove tabs to align arguments'.
 - Use imperative language in subject and description

 drivers/staging/axis-fifo/axis-fifo.c | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/axis-fifo/axis-fifo.c b/drivers/staging/axis-fifo/axis-fifo.c
index dfd2b357f484..d667dc80df47 100644
--- a/drivers/staging/axis-fifo/axis-fifo.c
+++ b/drivers/staging/axis-fifo/axis-fifo.c
@@ -103,17 +103,17 @@
  *           globals
  * ----------------------------
  */
-static int read_timeout = 1000; /* ms to wait before read() times out */
-static int write_timeout = 1000; /* ms to wait before write() times out */
+static long read_timeout = 1000; /* ms to wait before read() times out */
+static long write_timeout = 1000; /* ms to wait before write() times out */

 /* ----------------------------
  * module command-line arguments
  * ----------------------------
  */

-module_param(read_timeout, int, 0444);
+module_param(read_timeout, long, 0444);
 MODULE_PARM_DESC(read_timeout, "ms to wait before blocking read() timing out; set to -1 for no timeout");
-module_param(write_timeout, int, 0444);
+module_param(write_timeout, long, 0444);
 MODULE_PARM_DESC(write_timeout, "ms to wait before blocking write() timing out; set to -1 for no timeout");

 /* ----------------------------
@@ -384,9 +384,7 @@ static ssize_t axis_fifo_read(struct file *f, char __user *buf,
 		mutex_lock(&fifo->read_lock);
 		ret = wait_event_interruptible_timeout(fifo->read_queue,
 			ioread32(fifo->base_addr + XLLF_RDFO_OFFSET),
-				 (read_timeout >= 0) ?
-				  msecs_to_jiffies(read_timeout) :
-				  MAX_SCHEDULE_TIMEOUT);
+			read_timeout);

 		if (ret <= 0) {
 			if (ret == 0) {
@@ -528,9 +526,7 @@ static ssize_t axis_fifo_write(struct file *f, const char __user *buf,
 		ret = wait_event_interruptible_timeout(fifo->write_queue,
 			ioread32(fifo->base_addr + XLLF_TDFV_OFFSET)
 				 >= words_to_write,
-				 (write_timeout >= 0) ?
-				  msecs_to_jiffies(write_timeout) :
-				  MAX_SCHEDULE_TIMEOUT);
+			write_timeout);

 		if (ret <= 0) {
 			if (ret == 0) {
@@ -815,6 +811,16 @@ static int axis_fifo_probe(struct platform_device *pdev)
 	char *device_name;
 	int rc = 0; /* error return value */

+	if (read_timeout >= 0)
+		read_timeout = msecs_to_jiffies(read_timeout);
+	else
+		read_timeout = MAX_SCHEDULE_TIMEOUT;
+
+	if (write_timeout >= 0)
+		write_timeout = msecs_to_jiffies(write_timeout);
+	else
+		write_timeout = MAX_SCHEDULE_TIMEOUT;
+
 	/* ----------------------------
 	 *     init wrapper device
 	 * ----------------------------
--
2.34.1