[PATCH] iio: buffer: buffer-cb: drop double initialization of demux list

[PATCH] iio: buffer: buffer-cb: drop double initialization of demux list

[Nuno Sá via B4 Relay]

From: Nuno Sá <nuno.sa@analog.com>

Drop the call to INIT_LIST_HEAD(&cb_buff->buffer.demux_list). That's
already done in iio_buffer_init(&cb_buff->buffer).

Signed-off-by: Nuno Sá <nuno.sa@analog.com>
---
 drivers/iio/buffer/industrialio-buffer-cb.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/iio/buffer/industrialio-buffer-cb.c b/drivers/iio/buffer/industrialio-buffer-cb.c
index 4befc9f55201e..3e27385069edb 100644
--- a/drivers/iio/buffer/industrialio-buffer-cb.c
+++ b/drivers/iio/buffer/industrialio-buffer-cb.c
@@ -68,7 +68,6 @@ struct iio_cb_buffer *iio_channel_get_all_cb(struct device *dev,
 	cb_buff->private = private;
 	cb_buff->cb = cb;
 	cb_buff->buffer.access = &iio_cb_access;
-	INIT_LIST_HEAD(&cb_buff->buffer.demux_list);
 
 	cb_buff->channels = iio_channel_get_all(dev);
 	if (IS_ERR(cb_buff->channels)) {

---
base-commit: a10185367eccb4d79efdeb09eb59c964ca7659f7
change-id: 20250725-iio-minor-cleanup-94a31748efc5
--

Thanks!
- Nuno Sá

Re: [PATCH] iio: buffer: buffer-cb: drop double initialization of demux list

[Andy Shevchenko]

On Fri, Jul 25, 2025 at 9:32 AM Nuno Sá via B4 Relay
<devnull+nuno.sa.analog.com@kernel.org> wrote:
>
> From: Nuno Sá <nuno.sa@analog.com>
>
> Drop the call to INIT_LIST_HEAD(&cb_buff->buffer.demux_list). That's
> already done in iio_buffer_init(&cb_buff->buffer).

LGTM,
Reviewed-by: Andy Shevchenko <andy@kernel.org>

...

>         cb_buff->buffer.access = &iio_cb_access;
> -       INIT_LIST_HEAD(&cb_buff->buffer.demux_list);

Looking at this I think ideally it would be nice to have the buffer
type to be hidden from the users and only available via
getters/setters.

>         cb_buff->channels = iio_channel_get_all(dev);


-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH] iio: buffer: buffer-cb: drop double initialization of demux list

[Nuno Sá]

On Fri, Jul 25, 2025 at 10:47:19AM +0200, Andy Shevchenko wrote:
> On Fri, Jul 25, 2025 at 9:32 AM Nuno Sá via B4 Relay
> <devnull+nuno.sa.analog.com@kernel.org> wrote:
> >
> > From: Nuno Sá <nuno.sa@analog.com>
> >
> > Drop the call to INIT_LIST_HEAD(&cb_buff->buffer.demux_list). That's
> > already done in iio_buffer_init(&cb_buff->buffer).
> 
> LGTM,
> Reviewed-by: Andy Shevchenko <andy@kernel.org>
> 
> ...
> 
> >         cb_buff->buffer.access = &iio_cb_access;
> > -       INIT_LIST_HEAD(&cb_buff->buffer.demux_list);
> 
> Looking at this I think ideally it would be nice to have the buffer
> type to be hidden from the users and only available via
> getters/setters.

I would say it's arguable at the very least. The buffer callback is
itself a buffer implementation (extends the inner buffer object) so it
kind of make senses it can access it's internals via buffer_impl.h.

Note that 'struct iio_buffer buffer' is not a pointer in 'struct
iio_cb_buffer'...

- Nuno Sá

> 
> >         cb_buff->channels = iio_channel_get_all(dev);
> 
> 
> -- 
> With Best Regards,
> Andy Shevchenko

Re: [PATCH] iio: buffer: buffer-cb: drop double initialization of demux list

[Jonathan Cameron]

On Fri, 25 Jul 2025 07:32:55 +0100
Nuno Sá via B4 Relay <devnull+nuno.sa.analog.com@kernel.org> wrote:

> From: Nuno Sá <nuno.sa@analog.com>
> 
> Drop the call to INIT_LIST_HEAD(&cb_buff->buffer.demux_list). That's
> already done in iio_buffer_init(&cb_buff->buffer).
> 
> Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Applied. Thanks,