On Mon, Apr 26, 2021 at 8:50 PM Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
>
> From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
>
> No reason for this to be exposed to the drivers, so lets move it to the
> opaque structure.
Even though this looks straightforward, I am paranoid about it.
Mostly because of all the chardev juggling that I tried.
Reviewed-by: Alexandru Ardelean <ardeleanalex@xxxxxxxxx>
>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> ---
> drivers/iio/industrialio-core.c | 20 +++++++++++---------
> include/linux/iio/iio-opaque.h | 2 ++
> include/linux/iio/iio.h | 2 --
> 3 files changed, 13 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index f3b38d69b7e1..6fbe29f0b1de 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -1715,8 +1715,9 @@ EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
> **/
> static int iio_chrdev_open(struct inode *inode, struct file *filp)
> {
> - struct iio_dev *indio_dev = container_of(inode->i_cdev,
> - struct iio_dev, chrdev);
> + struct iio_dev_opaque *iio_dev_opaque =
> + container_of(inode->i_cdev, struct iio_dev_opaque, chrdev);
> + struct iio_dev *indio_dev = &iio_dev_opaque->indio_dev;
> struct iio_dev_buffer_pair *ib;
>
> if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
> @@ -1749,8 +1750,9 @@ static int iio_chrdev_open(struct inode *inode, struct file *filp)
> static int iio_chrdev_release(struct inode *inode, struct file *filp)
> {
> struct iio_dev_buffer_pair *ib = filp->private_data;
> - struct iio_dev *indio_dev = container_of(inode->i_cdev,
> - struct iio_dev, chrdev);
> + struct iio_dev_opaque *iio_dev_opaque =
> + container_of(inode->i_cdev, struct iio_dev_opaque, chrdev);
> + struct iio_dev *indio_dev = &iio_dev_opaque->indio_dev;
> kfree(ib);
> clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
> iio_device_put(indio_dev);
> @@ -1901,19 +1903,19 @@ int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
> indio_dev->setup_ops = &noop_ring_setup_ops;
>
> if (iio_dev_opaque->attached_buffers_cnt)
> - cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
> + cdev_init(&iio_dev_opaque->chrdev, &iio_buffer_fileops);
> else if (iio_dev_opaque->event_interface)
> - cdev_init(&indio_dev->chrdev, &iio_event_fileops);
> + cdev_init(&iio_dev_opaque->chrdev, &iio_event_fileops);
>
> if (iio_dev_opaque->attached_buffers_cnt || iio_dev_opaque->event_interface) {
> indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), iio_dev_opaque->id);
> - indio_dev->chrdev.owner = this_mod;
> + iio_dev_opaque->chrdev.owner = this_mod;
> }
>
> /* assign device groups now; they should be all registered now */
> indio_dev->dev.groups = iio_dev_opaque->groups;
>
> - ret = cdev_device_add(&indio_dev->chrdev, &indio_dev->dev);
> + ret = cdev_device_add(&iio_dev_opaque->chrdev, &indio_dev->dev);
> if (ret < 0)
> goto error_unreg_eventset;
>
> @@ -1940,7 +1942,7 @@ void iio_device_unregister(struct iio_dev *indio_dev)
> struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
> struct iio_ioctl_handler *h, *t;
>
> - cdev_device_del(&indio_dev->chrdev, &indio_dev->dev);
> + cdev_device_del(&iio_dev_opaque->chrdev, &indio_dev->dev);
>
> mutex_lock(&iio_dev_opaque->info_exist_lock);
>
> diff --git a/include/linux/iio/iio-opaque.h b/include/linux/iio/iio-opaque.h
> index 538b4b5ef1a9..2f8ef5d15a66 100644
> --- a/include/linux/iio/iio-opaque.h
> +++ b/include/linux/iio/iio-opaque.h
> @@ -24,6 +24,7 @@
> * @legacy_scan_el_group: attribute group for legacy scan elements attribute group
> * @legacy_buffer_group: attribute group for legacy buffer attributes group
> * @scan_index_timestamp: cache of the index to the timestamp
> + * @chrdev: associated character device
> * @debugfs_dentry: device specific debugfs dentry
> * @cached_reg_addr: cached register address for debugfs reads
> * @read_buf: read buffer to be used for the initial reg read
> @@ -49,6 +50,7 @@ struct iio_dev_opaque {
> struct attribute_group legacy_buffer_group;
>
> unsigned int scan_index_timestamp;
> + struct cdev chrdev;
>
> #if defined(CONFIG_DEBUG_FS)
> struct dentry *debugfs_dentry;
> diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
> index a12bbd8b1e74..586e2dc4fbf3 100644
> --- a/include/linux/iio/iio.h
> +++ b/include/linux/iio/iio.h
> @@ -512,7 +512,6 @@ struct iio_buffer_setup_ops {
> * @clock_id: [INTERN] timestamping clock posix identifier
> * @setup_ops: [DRIVER] callbacks to call before and after buffer
> * enable/disable
> - * @chrdev: [INTERN] associated character device
> * @flags: [INTERN] file ops related flags including busy flag.
> * @priv: [DRIVER] reference to driver's private information
> * **MUST** be accessed **ONLY** via iio_priv() helper
> @@ -542,7 +541,6 @@ struct iio_dev {
> const struct iio_info *info;
> clockid_t clock_id;
> const struct iio_buffer_setup_ops *setup_ops;
> - struct cdev chrdev;
>
> unsigned long flags;
> void *priv;
> --
> 2.31.1
>
