iio: trigger: implement devm_iio_trigger_alloc/devm_iio_triger_free

Add a resource managed devm_iio_trigger_alloc()/devm_iio_triger_free()
to automatically clean up triggers allocated by IIO drivers, thus
leading to simplified IIO drivers code.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Kyunmin Park <kyungmin.park@samsung.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

1 files changed, 68 insertions, 4 deletions

diff --git a/drivers/iio/industrialio-trigger.c b/drivers/iio/industrialio-trigger.c
index 0dd9bb873130..bf5e70a32d3f 100644
--- a/drivers/iio/industrialio-trigger.c
+++ b/drivers/iio/industrialio-trigger.c
@@ -424,9 +424,8 @@ static void iio_trig_subirqunmask(struct irq_data *d)
         trig->subirqs[d->irq - trig->subirq_base].enabled = true;
 }
 
-struct iio_trigger *iio_trigger_alloc(const char *fmt, ...)
+static struct iio_trigger *viio_trigger_alloc(const char *fmt, va_list vargs)
 {
-        va_list vargs;
         struct iio_trigger *trig;
         trig = kzalloc(sizeof *trig, GFP_KERNEL);
         if (trig) {
@@ -444,9 +443,8 @@ struct iio_trigger *iio_trigger_alloc(const char *fmt, ...)
                         kfree(trig);
                         return NULL;
                 }
-                va_start(vargs, fmt);
+
                 trig->name = kvasprintf(GFP_KERNEL, fmt, vargs);
-                va_end(vargs);
                 if (trig->name == NULL) {
                         irq_free_descs(trig->subirq_base,
                                        CONFIG_IIO_CONSUMERS_PER_TRIGGER);
@@ -467,6 +465,19 @@ struct iio_trigger *iio_trigger_alloc(const char *fmt, ...)
                 }
                 get_device(&trig->dev);
         }
+
+        return trig;
+}
+
+struct iio_trigger *iio_trigger_alloc(const char *fmt, ...)
+{
+        struct iio_trigger *trig;
+        va_list vargs;
+
+        va_start(vargs, fmt);
+        trig = viio_trigger_alloc(fmt, vargs);
+        va_end(vargs);
+
         return trig;
 }
 EXPORT_SYMBOL(iio_trigger_alloc);
@@ -478,6 +489,59 @@ void iio_trigger_free(struct iio_trigger *trig)
 }
 EXPORT_SYMBOL(iio_trigger_free);
 
+static void devm_iio_trigger_release(struct device *dev, void *res)
+{
+        iio_trigger_free(*(struct iio_trigger **)res);
+}
+
+static int devm_iio_trigger_match(struct device *dev, void *res, void *data)
+{
+        struct iio_trigger **r = res;
+
+        if (!r || !*r) {
+                WARN_ON(!r || !*r);
+                return 0;
+        }
+
+        return *r == data;
+}
+
+struct iio_trigger *devm_iio_trigger_alloc(struct device *dev,
+                                                const char *fmt, ...)
+{
+        struct iio_trigger **ptr, *trig;
+        va_list vargs;
+
+        ptr = devres_alloc(devm_iio_trigger_release, sizeof(*ptr),
+                           GFP_KERNEL);
+        if (!ptr)
+                return NULL;
+
+        /* use raw alloc_dr for kmalloc caller tracing */
+        va_start(vargs, fmt);
+        trig = viio_trigger_alloc(fmt, vargs);
+        va_end(vargs);
+        if (trig) {
+                *ptr = trig;
+                devres_add(dev, ptr);
+        } else {
+                devres_free(ptr);
+        }
+
+        return trig;
+}
+EXPORT_SYMBOL_GPL(devm_iio_trigger_alloc);
+
+void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig)
+{
+        int rc;
+
+        rc = devres_release(dev, devm_iio_trigger_release,
+                            devm_iio_trigger_match, iio_trig);
+        WARN_ON(rc);
+}
+EXPORT_SYMBOL_GPL(devm_iio_trigger_free);
+
 void iio_device_register_trigger_consumer(struct iio_dev *indio_dev)
 {
         indio_dev->groups[indio_dev->groupcounter++] =