diff options
Diffstat (limited to 'drivers/iio/industrialio-trigger.c')
| -rw-r--r-- | drivers/iio/industrialio-trigger.c | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/drivers/iio/industrialio-trigger.c b/drivers/iio/industrialio-trigger.c index 7ad82fdd3e5b..e1e104845e38 100644 --- a/drivers/iio/industrialio-trigger.c +++ b/drivers/iio/industrialio-trigger.c @@ -119,6 +119,22 @@ void iio_trigger_unregister(struct iio_trigger *trig_info) } EXPORT_SYMBOL(iio_trigger_unregister); +int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig) +{ + if (!indio_dev || !trig) + return -EINVAL; + + mutex_lock(&indio_dev->mlock); + WARN_ON(indio_dev->trig_readonly); + + indio_dev->trig = iio_trigger_get(trig); + indio_dev->trig_readonly = true; + mutex_unlock(&indio_dev->mlock); + + return 0; +} +EXPORT_SYMBOL(iio_trigger_set_immutable); + /* Search for trigger by name, assuming iio_trigger_list_lock held */ static struct iio_trigger *__iio_trigger_find_by_name(const char *name) { @@ -255,6 +271,14 @@ static int iio_trigger_attach_poll_func(struct iio_trigger *trig, goto out_free_irq; } + /* + * Check if we just registered to our own trigger: we determine that + * this is the case if the IIO device and the trigger device share the + * same parent device. + */ + if (pf->indio_dev->dev.parent == trig->dev.parent) + trig->attached_own_device = true; + return ret; out_free_irq: @@ -279,6 +303,8 @@ static int iio_trigger_detach_poll_func(struct iio_trigger *trig, if (ret) return ret; } + if (pf->indio_dev->dev.parent == trig->dev.parent) + trig->attached_own_device = false; iio_trigger_put_irq(trig, pf->irq); free_irq(pf->irq, pf); module_put(pf->indio_dev->info->driver_module); @@ -384,6 +410,10 @@ static ssize_t iio_trigger_write_current(struct device *dev, mutex_unlock(&indio_dev->mlock); return -EBUSY; } + if (indio_dev->trig_readonly) { + mutex_unlock(&indio_dev->mlock); + return -EPERM; + } mutex_unlock(&indio_dev->mlock); trig = iio_trigger_find_by_name(buf, len); @@ -622,6 +652,71 @@ void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig) } EXPORT_SYMBOL_GPL(devm_iio_trigger_free); +static void devm_iio_trigger_unreg(struct device *dev, void *res) +{ + iio_trigger_unregister(*(struct iio_trigger **)res); +} + +/** + * devm_iio_trigger_register - Resource-managed iio_trigger_register() + * @dev: device this trigger was allocated for + * @trig_info: trigger to register + * + * Managed iio_trigger_register(). The IIO trigger registered with this + * function is automatically unregistered on driver detach. This function + * calls iio_trigger_register() internally. Refer to that function for more + * information. + * + * If an iio_trigger registered with this function needs to be unregistered + * separately, devm_iio_trigger_unregister() must be used. + * + * RETURNS: + * 0 on success, negative error number on failure. + */ +int devm_iio_trigger_register(struct device *dev, struct iio_trigger *trig_info) +{ + struct iio_trigger **ptr; + int ret; + + ptr = devres_alloc(devm_iio_trigger_unreg, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return -ENOMEM; + + *ptr = trig_info; + ret = iio_trigger_register(trig_info); + if (!ret) + devres_add(dev, ptr); + else + devres_free(ptr); + + return ret; +} +EXPORT_SYMBOL_GPL(devm_iio_trigger_register); + +/** + * devm_iio_trigger_unregister - Resource-managed iio_trigger_unregister() + * @dev: device this iio_trigger belongs to + * @trig_info: the trigger associated with the device + * + * Unregister trigger registered with devm_iio_trigger_register(). + */ +void devm_iio_trigger_unregister(struct device *dev, + struct iio_trigger *trig_info) +{ + int rc; + + rc = devres_release(dev, devm_iio_trigger_unreg, devm_iio_trigger_match, + trig_info); + WARN_ON(rc); +} +EXPORT_SYMBOL_GPL(devm_iio_trigger_unregister); + +bool iio_trigger_using_own(struct iio_dev *indio_dev) +{ + return indio_dev->trig->attached_own_device; +} +EXPORT_SYMBOL(iio_trigger_using_own); + void iio_device_register_trigger_consumer(struct iio_dev *indio_dev) { indio_dev->groups[indio_dev->groupcounter++] = |