[PATCH v4 26/40] media: em28xx: cx231xx: optimize drivers by using find_and_set_bit()

Yury Norov
2024-06-20T17:58:23Z

Functions in the media/usb drivers opencode find_and_set_bit(). Simplify
them by using the function.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
---
drivers/media/usb/cx231xx/cx231xx-cards.c | 17 +++++-----
drivers/media/usb/em28xx/em28xx-cards.c | 38 ++++++++++-------------
2 files changed, 23 insertions(+), 32 deletions(-)

diff --git a/drivers/media/usb/cx231xx/cx231xx-cards.c b/drivers/media/usb/cx231xx/cx231xx-cards.c
index 92efe6c1f47b..8bdfbc4454f1 100644
--- a/drivers/media/usb/cx231xx/cx231xx-cards.c
+++ b/drivers/media/usb/cx231xx/cx231xx-cards.c
@@ -9,6 +9,7 @@
*/

#include "cx231xx.h"
+#include <linux/find_atomic.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
@@ -1708,16 +1709,12 @@ static int cx231xx_usb_probe(struct usb_interface *interface,
return -ENODEV;

/* Check to see next free device and mark as used */
- do {
- nr = find_first_zero_bit(&cx231xx_devused, CX231XX_MAXBOARDS);
- if (nr >= CX231XX_MAXBOARDS) {
- /* No free device slots */
- dev_err(d,
- "Supports only %i devices.\n",
- CX231XX_MAXBOARDS);
- return -ENOMEM;
- }
- } while (test_and_set_bit(nr, &cx231xx_devused));
+ nr = find_and_set_bit(&cx231xx_devused, CX231XX_MAXBOARDS);
+ if (nr >= CX231XX_MAXBOARDS) {
+ /* No free device slots */
+ dev_err(d, "Supports only %i devices.\n", CX231XX_MAXBOARDS);
+ return -ENOMEM;
+ }

udev = usb_get_dev(interface_to_usbdev(interface));

diff --git a/drivers/media/usb/em28xx/em28xx-cards.c b/drivers/media/usb/em28xx/em28xx-cards.c
index bae76023cf71..59e6d7f894ad 100644
--- a/drivers/media/usb/em28xx/em28xx-cards.c
+++ b/drivers/media/usb/em28xx/em28xx-cards.c
@@ -11,6 +11,7 @@

#include "em28xx.h"

+#include <linux/find_atomic.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
@@ -3684,17 +3685,14 @@ static int em28xx_duplicate_dev(struct em28xx *dev)
return -ENOMEM;
}
/* Check to see next free device and mark as used */
- do {
- nr = find_first_zero_bit(em28xx_devused, EM28XX_MAXBOARDS);
- if (nr >= EM28XX_MAXBOARDS) {
- /* No free device slots */
- dev_warn(&dev->intf->dev, ": Supports only %i em28xx boards.\n",
- EM28XX_MAXBOARDS);
- kfree(sec_dev);
- dev->dev_next = NULL;
- return -ENOMEM;
- }
- } while (test_and_set_bit(nr, em28xx_devused));
+ nr = find_and_set_bit(em28xx_devused, EM28XX_MAXBOARDS);
+ if (nr >= EM28XX_MAXBOARDS) {
+ /* No free device slots */
+ dev_warn(&dev->intf->dev, ": Supports only %i em28xx boards.\n", EM28XX_MAXBOARDS);
+ kfree(sec_dev);
+ dev->dev_next = NULL;
+ return -ENOMEM;
+ }
sec_dev->devno = nr;
snprintf(sec_dev->name, 28, "em28xx #%d", nr);
sec_dev->dev_next = NULL;
@@ -3827,17 +3825,13 @@ static int em28xx_usb_probe(struct usb_interface *intf,
udev = usb_get_dev(interface_to_usbdev(intf));

/* Check to see next free device and mark as used */
- do {
- nr = find_first_zero_bit(em28xx_devused, EM28XX_MAXBOARDS);
- if (nr >= EM28XX_MAXBOARDS) {
- /* No free device slots */
- dev_err(&intf->dev,
- "Driver supports up to %i em28xx boards.\n",
- EM28XX_MAXBOARDS);
- retval = -ENOMEM;
- goto err_no_slot;
- }
- } while (test_and_set_bit(nr, em28xx_devused));
+ nr = find_and_set_bit(em28xx_devused, EM28XX_MAXBOARDS);
+ if (nr >= EM28XX_MAXBOARDS) {
+ /* No free device slots */
+ dev_err(&intf->dev, "Driver supports up to %i em28xx boards.\n", EM28XX_MAXBOARDS);
+ retval = -ENOMEM;
+ goto err_no_slot;
+ }

/* Don't register audio interfaces */
if (intf->altsetting[0].desc.bInterfaceClass == USB_CLASS_AUDIO) {
--
2.43.0