[PATCH v5] staging: axis-fifo: initialize timeouts in probe only

From: Khadija Kamran
Date: Thu Mar 16 2023 - 08:56:34 EST


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@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Khadija Kamran <kamrankhadijadj@xxxxxxxxx>
---

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