iio: core: move @id from struct iio_dev to struct iio_dev_opaque

Continuing from Alexandru Ardelean's introduction of the split between
driver modifiable fields and those that should only be set by the core.

This could have been done in two steps to make the actual move after
introducing iio_device_id() but there seemed limited point to that
given how mechanical the majority of the patch is.

Includes fixup from Alex for missing mxs-lradc-adc conversion.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Link: https://lore.kernel.org/r/20210426174911.397061-2-jic23@kernel.org

1 files changed, 19 insertions, 5 deletions

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 3fdcf2d4997a..ec21341c6322 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -169,6 +169,20 @@ static const char * const iio_chan_info_postfix[] = {
 	[IIO_CHAN_INFO_THERMOCOUPLE_TYPE] = "thermocouple_type",
 	[IIO_CHAN_INFO_CALIBAMBIENT] = "calibambient",
 };
+/**
+ * iio_device_id() - query the unique ID for the device
+ * @indio_dev:		Device structure whose ID is being queried
+ *
+ * The IIO device ID is a unique index used for example for the naming
+ * of the character device /dev/iio\:device[ID]
+ */
+int iio_device_id(struct iio_dev *indio_dev)
+{
+	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
+
+	return iio_dev_opaque->id;
+}
+EXPORT_SYMBOL_GPL(iio_device_id);
 
 /**
  * iio_sysfs_match_string_with_gaps - matches given string in an array with gaps
@@ -1588,7 +1602,7 @@ static void iio_dev_release(struct device *device)
 
 	iio_device_detach_buffers(indio_dev);
 
-	ida_simple_remove(&iio_ida, indio_dev->id);
+	ida_simple_remove(&iio_ida, iio_dev_opaque->id);
 	kfree(iio_dev_opaque);
 }
 
@@ -1631,14 +1645,14 @@ struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv)
 	mutex_init(&indio_dev->info_exist_lock);
 	INIT_LIST_HEAD(&iio_dev_opaque->channel_attr_list);
 
-	indio_dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
-	if (indio_dev->id < 0) {
+	iio_dev_opaque->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
+	if (iio_dev_opaque->id < 0) {
 		/* cannot use a dev_err as the name isn't available */
 		pr_err("failed to get device id\n");
 		kfree(iio_dev_opaque);
 		return NULL;
 	}
-	dev_set_name(&indio_dev->dev, "iio:device%d", indio_dev->id);
+	dev_set_name(&indio_dev->dev, "iio:device%d", iio_dev_opaque->id);
 	INIT_LIST_HEAD(&iio_dev_opaque->buffer_list);
 	INIT_LIST_HEAD(&iio_dev_opaque->ioctl_handlers);
 
@@ -1891,7 +1905,7 @@ int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
 		cdev_init(&indio_dev->chrdev, &iio_event_fileops);
 
 	if (iio_dev_opaque->attached_buffers_cnt || iio_dev_opaque->event_interface) {
-		indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
+		indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), iio_dev_opaque->id);
 		indio_dev->chrdev.owner = this_mod;
 	}