2023-12-02 16:56:21

by Marcus Folkesson

Subject: [PATCH v3] Input: pxrc - simplify mutex handling with guard macro

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

Signed-off-by: Marcus Folkesson <[email protected]>
---
Changes in v3:
- Rename retval->error in pxrc_open() as it now only holds error code
- Return early instead of assign retval in pxrc_resume()
- Link to v2: https://lore.kernel.org/r/[email protected]

Changes in v2:
- Add guard in pxrc_open()
- Link to v1: https://lore.kernel.org/r/[email protected]
---
drivers/input/joystick/pxrc.c | 42 ++++++++++++++++++------------------------
1 file changed, 18 insertions(+), 24 deletions(-)

diff --git a/drivers/input/joystick/pxrc.c b/drivers/input/joystick/pxrc.c
index ea2bf5951d67..52d9eab667b7 100644
--- a/drivers/input/joystick/pxrc.c
+++ b/drivers/input/joystick/pxrc.c
@@ -5,15 +5,17 @@
* Copyright (C) 2018 Marcus Folkesson <[email protected]>
*/

-#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
@@ -81,33 +83,28 @@ static void pxrc_usb_irq(struct urb *urb)
static int pxrc_open(struct input_dev *input)
{
struct pxrc *pxrc = input_get_drvdata(input);
- int retval;
+ int error;

- mutex_lock(&pxrc->pm_mutex);
- retval = usb_submit_urb(pxrc->urb, GFP_KERNEL);
- if (retval) {
+ guard(mutex)(&pxrc->pm_mutex);
+ error = usb_submit_urb(pxrc->urb, GFP_KERNEL);
+ if (error) {
dev_err(&pxrc->intf->dev,
"%s - usb_submit_urb failed, error: %d\n",
- __func__, retval);
- retval = -EIO;
- goto out;
+ __func__, error);
+ 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;
}
@@ -219,14 +215,12 @@ static int pxrc_suspend(struct usb_interface *intf, pm_message_t message)
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;
+ return -EIO;

- mutex_unlock(&pxrc->pm_mutex);
- return retval;
+ return 0;
}

static int pxrc_pre_reset(struct usb_interface *intf)

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

Best regards,
--
Marcus Folkesson <[email protected]>

2023-12-10 06:40:25

by Dmitry Torokhov

Subject: Re: [PATCH v3] Input: pxrc - simplify mutex handling with guard macro

On Sat, Dec 02, 2023 at 05:59:48PM +0100, Marcus Folkesson wrote:
> Use the guard(mutex) macro for handle mutex lock/unlocks.
>
> Signed-off-by: Marcus Folkesson <[email protected]>

Applied, thank you.

--
Dmitry