[PATCH] spi: spidev: replace usage of found with dedicated list iterator variable

[PATCH] spi: spidev: replace usage of found with dedicated list iterator variable

[Jakob Koschel]

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
---
 drivers/spi/spidev.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index a5cceca8b82b..2c5e685826ad 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -561,19 +561,20 @@ spidev_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 
 static int spidev_open(struct inode *inode, struct file *filp)
 {
-	struct spidev_data	*spidev;
+	struct spidev_data	*spidev = NULL, *iter;
 	int			status = -ENXIO;
 
 	mutex_lock(&device_list_lock);
 
-	list_for_each_entry(spidev, &device_list, device_entry) {
-		if (spidev->devt == inode->i_rdev) {
+	list_for_each_entry(iter, &device_list, device_entry) {
+		if (iter->devt == inode->i_rdev) {
 			status = 0;
+			spidev = iter;
 			break;
 		}
 	}
 
-	if (status) {
+	if (!spidev) {
 		pr_debug("spidev: nothing for minor %d\n", iminor(inode));
 		goto err_find_dev;
 	}

base-commit: f443e374ae131c168a065ea1748feac6b2e76613
-- 
2.25.1

Re: [PATCH] spi: spidev: replace usage of found with dedicated list iterator variable

[Mark Brown]

On Thu, 24 Mar 2022 08:25:34 +0100, Jakob Koschel wrote:
> To move the list iterator variable into the list_for_each_entry_*()
> macro in the future it should be avoided to use the list iterator
> variable after the loop body.
> 
> To *never* use the list iterator variable after the loop it was
> concluded to use a separate iterator variable instead of a
> found boolean [1].
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/1] spi: spidev: replace usage of found with dedicated list iterator variable
      commit: d50d7e91c6e5ccd71f21ba1aec3fef7ee4229fd6

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark