iio: trigger: move to the cleanup.h magic

Use the new cleanup magic for handling mutexes in IIO. This allows us to
greatly simplify some code paths.

Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240229-iio-use-cleanup-magic-v3-2-c3d34889ae3c@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/industrialio-trigger.c b/drivers/iio/industrialio-trigger.c
index 18f83158f637f119f8db1e848740708256e5c0c5..16de57846bd9c16a48812ffd94793544122f5d12 100644 (file)
--- a/drivers/iio/industrialio-trigger.c
+++ b/drivers/iio/industrialio-trigger.c
@@ -4,6 +4,7 @@
  * Copyright (c) 2008 Jonathan Cameron
  */
 
+#include <linux/cleanup.h>
 #include <linux/kernel.h>
 #include <linux/idr.h>
 #include <linux/err.h>
@@ -80,19 +81,18 @@ int iio_trigger_register(struct iio_trigger *trig_info)
                goto error_unregister_id;
 
        /* Add to list of available triggers held by the IIO core */
-       mutex_lock(&iio_trigger_list_lock);
-       if (__iio_trigger_find_by_name(trig_info->name)) {
-               pr_err("Duplicate trigger name '%s'\n", trig_info->name);
-               ret = -EEXIST;
-               goto error_device_del;
+       scoped_guard(mutex, &iio_trigger_list_lock) {
+               if (__iio_trigger_find_by_name(trig_info->name)) {
+                       pr_err("Duplicate trigger name '%s'\n", trig_info->name);
+                       ret = -EEXIST;
+                       goto error_device_del;
+               }
+               list_add_tail(&trig_info->list, &iio_trigger_list);
        }
-       list_add_tail(&trig_info->list, &iio_trigger_list);
-       mutex_unlock(&iio_trigger_list_lock);
 
        return 0;
 
 error_device_del:
-       mutex_unlock(&iio_trigger_list_lock);
        device_del(&trig_info->dev);
 error_unregister_id:
        ida_free(&iio_trigger_ida, trig_info->id);
@@ -102,9 +102,8 @@ EXPORT_SYMBOL(iio_trigger_register);
 
 void iio_trigger_unregister(struct iio_trigger *trig_info)
 {
-       mutex_lock(&iio_trigger_list_lock);
-       list_del(&trig_info->list);
-       mutex_unlock(&iio_trigger_list_lock);
+       scoped_guard(mutex, &iio_trigger_list_lock)
+               list_del(&trig_info->list);
 
        ida_free(&iio_trigger_ida, trig_info->id);
        /* Possible issue in here */
@@ -120,12 +119,11 @@ int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *tri
                return -EINVAL;
 
        iio_dev_opaque = to_iio_dev_opaque(indio_dev);
-       mutex_lock(&iio_dev_opaque->mlock);
+       guard(mutex)(&iio_dev_opaque->mlock);
        WARN_ON(iio_dev_opaque->trig_readonly);
 
        indio_dev->trig = iio_trigger_get(trig);
        iio_dev_opaque->trig_readonly = true;
-       mutex_unlock(&iio_dev_opaque->mlock);
 
        return 0;
 }
@@ -145,18 +143,14 @@ static struct iio_trigger *__iio_trigger_find_by_name(const char *name)
 
 static struct iio_trigger *iio_trigger_acquire_by_name(const char *name)
 {
-       struct iio_trigger *trig = NULL, *iter;
+       struct iio_trigger *iter;
 
-       mutex_lock(&iio_trigger_list_lock);
+       guard(mutex)(&iio_trigger_list_lock);
        list_for_each_entry(iter, &iio_trigger_list, list)
-               if (sysfs_streq(iter->name, name)) {
-                       trig = iter;
-                       iio_trigger_get(trig);
-                       break;
-               }
-       mutex_unlock(&iio_trigger_list_lock);
+               if (sysfs_streq(iter->name, name))
+                       return iio_trigger_get(iter);
 
-       return trig;
+       return NULL;
 }
 
 static void iio_reenable_work_fn(struct work_struct *work)
@@ -259,22 +253,21 @@ static int iio_trigger_get_irq(struct iio_trigger *trig)
 {
        int ret;
 
-       mutex_lock(&trig->pool_lock);
-       ret = bitmap_find_free_region(trig->pool,
-                                     CONFIG_IIO_CONSUMERS_PER_TRIGGER,
-                                     ilog2(1));
-       mutex_unlock(&trig->pool_lock);
-       if (ret >= 0)
-               ret += trig->subirq_base;
+       scoped_guard(mutex, &trig->pool_lock) {
+               ret = bitmap_find_free_region(trig->pool,
+                                             CONFIG_IIO_CONSUMERS_PER_TRIGGER,
+                                             ilog2(1));
+               if (ret < 0)
+                       return ret;
+       }
 
-       return ret;
+       return ret + trig->subirq_base;
 }
 
 static void iio_trigger_put_irq(struct iio_trigger *trig, int irq)
 {
-       mutex_lock(&trig->pool_lock);
+       guard(mutex)(&trig->pool_lock);
        clear_bit(irq - trig->subirq_base, trig->pool);
-       mutex_unlock(&trig->pool_lock);
 }
 
 /* Complexity in here.  With certain triggers (datardy) an acknowledgement
@@ -451,16 +444,12 @@ static ssize_t current_trigger_store(struct device *dev,
        struct iio_trigger *trig;
        int ret;
 
-       mutex_lock(&iio_dev_opaque->mlock);
-       if (iio_dev_opaque->currentmode == INDIO_BUFFER_TRIGGERED) {
-               mutex_unlock(&iio_dev_opaque->mlock);
-               return -EBUSY;
-       }
-       if (iio_dev_opaque->trig_readonly) {
-               mutex_unlock(&iio_dev_opaque->mlock);
-               return -EPERM;
+       scoped_guard(mutex, &iio_dev_opaque->mlock) {
+               if (iio_dev_opaque->currentmode == INDIO_BUFFER_TRIGGERED)
+                       return -EBUSY;
+               if (iio_dev_opaque->trig_readonly)
+                       return -EPERM;
        }
-       mutex_unlock(&iio_dev_opaque->mlock);
 
        trig = iio_trigger_acquire_by_name(buf);
        if (oldtrig == trig) {