[PATCH v2] Input: pxrc - simplify mutex handling with guard macro

From: Marcus Folkesson
Date: Fri Dec 01 2023 - 08:13:03 EST


Use the guard(mutex) macro for handle mutex lock/unlocks.

Signed-off-by: Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
---
Changes in v2:
- Add guard in pxrc_open()
- Link to v1: https://lore.kernel.org/r/20231201-pxrc-guard-v1-1-38937e657368@xxxxxxxxx
---
drivers/input/joystick/pxrc.c | 29 ++++++++++++-----------------
1 file changed, 12 insertions(+), 17 deletions(-)

diff --git a/drivers/input/joystick/pxrc.c b/drivers/input/joystick/pxrc.c
index ea2bf5951d67..d4b699418361 100644
--- a/drivers/input/joystick/pxrc.c
+++ b/drivers/input/joystick/pxrc.c
@@ -5,15 +5,17 @@
* Copyright (C) 2018 Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
*/

-#include <linux/kernel.h>
+#include <linux/cleanup.h>
#include <linux/errno.h>
-#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
#include <linux/uaccess.h>
+
#include <linux/usb.h>
#include <linux/usb/input.h>
-#include <linux/mutex.h>
-#include <linux/input.h>

#define PXRC_VENDOR_ID 0x1781
#define PXRC_PRODUCT_ID 0x0898
@@ -83,31 +85,26 @@ static int pxrc_open(struct input_dev *input)
struct pxrc *pxrc = input_get_drvdata(input);
int retval;

- mutex_lock(&pxrc->pm_mutex);
+ guard(mutex)(&pxrc->pm_mutex);
retval = usb_submit_urb(pxrc->urb, GFP_KERNEL);
if (retval) {
dev_err(&pxrc->intf->dev,
"%s - usb_submit_urb failed, error: %d\n",
__func__, retval);
- retval = -EIO;
- goto out;
+ return -EIO;
}

pxrc->is_open = true;
-
-out:
- mutex_unlock(&pxrc->pm_mutex);
- return retval;
+ return 0;
}

static void pxrc_close(struct input_dev *input)
{
struct pxrc *pxrc = input_get_drvdata(input);

- mutex_lock(&pxrc->pm_mutex);
+ guard(mutex)(&pxrc->pm_mutex);
usb_kill_urb(pxrc->urb);
pxrc->is_open = false;
- mutex_unlock(&pxrc->pm_mutex);
}

static void pxrc_free_urb(void *_pxrc)
@@ -208,10 +205,9 @@ static int pxrc_suspend(struct usb_interface *intf, pm_message_t message)
{
struct pxrc *pxrc = usb_get_intfdata(intf);

- mutex_lock(&pxrc->pm_mutex);
+ guard(mutex)(&pxrc->pm_mutex);
if (pxrc->is_open)
usb_kill_urb(pxrc->urb);
- mutex_unlock(&pxrc->pm_mutex);

return 0;
}
@@ -221,11 +217,10 @@ static int pxrc_resume(struct usb_interface *intf)
struct pxrc *pxrc = usb_get_intfdata(intf);
int retval = 0;

- mutex_lock(&pxrc->pm_mutex);
+ guard(mutex)(&pxrc->pm_mutex);
if (pxrc->is_open && usb_submit_urb(pxrc->urb, GFP_KERNEL) < 0)
retval = -EIO;

- mutex_unlock(&pxrc->pm_mutex);
return retval;
}


---
base-commit: ffc253263a1375a65fa6c9f62a893e9767fbebfa
change-id: 20231201-pxrc-guard-03dc35771b36

Best regards,
--
Marcus Folkesson <marcus.folkesson@xxxxxxxxx>