On Sun, 2020-05-03 at 13:51 +0100, Jonathan Cameron wrote:
> On Wed, 29 Apr 2020 18:17:39 +0300
> Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> wrote:
>
> > From: Lars-Peter Clausen <lars@xxxxxxxxxx>
> >
> > Let the core handle the buffer scan mask management including allocation
> > and channel selection. Having this handled in a central place rather than
> > open-coding it all over the place will make it easier to change the
> > implementation (if needed).
> > At the very least, this change abstracts scan-mask management away from
> > buffer implementations.
> >
> > Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
> > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
>
> I'm not 100% happy with including the buffer_impl.h header in the inkern
> code, but I can't see a simple way around it.
I actually also tried to not do it [I suspect Lars may have tried as well].
But you end up either having to expose 'struct iio_channel' outside of
'inkern.c' or having to include 'iio/consumer.h' in industrialio-buffer.c
Since there will be a V3, I will probably try to look again at a potential
different solution. Maybe there is a better solution I haven't considered.
>
> However, there are some missing statics in here and I'm feeling lazy
> so not going to fix them up for you.
>
No problem from my side.
I'll fix them up.
I prefer it when people don't cleanup after me. Makes me feel less guilty.
Though I will admit, it's a double-edged feeling: I am greatful when someone
cleans up after me, but I also feel slightly guilty [about it].
> Thanks,
>
> Jonathan
>
> > ---
> >
> > Changelog v1 -> v2:
> > - split away from initial series; the `buffer->channel_mask` attribute
> > requires a bit more dicussion; or may even be dropped; just these 2
> > patches helps with diff-ing 2 trees, as applying patches between my
> > work tree & IIO has fewer conflicts
> > - return -EINVAL if masklength is 0 in iio_buffer_alloc_scanmask()
> > - convert 2nd parameter to `unsigned int masklength` in
> > iio_buffer_alloc_scanmask()
> >
> > drivers/iio/buffer/industrialio-buffer-cb.c | 17 +++++-----
> > drivers/iio/industrialio-buffer.c | 36 +++++++++++++++------
> > drivers/iio/inkern.c | 15 +++++++++
> > include/linux/iio/consumer.h | 10 ++++++
> > 4 files changed, 59 insertions(+), 19 deletions(-)
> >
> > diff --git a/drivers/iio/buffer/industrialio-buffer-cb.c
> > b/drivers/iio/buffer/industrialio-buffer-cb.c
> > index 47c96f7f4976..dc5bb2ab533a 100644
> > --- a/drivers/iio/buffer/industrialio-buffer-cb.c
> > +++ b/drivers/iio/buffer/industrialio-buffer-cb.c
> > @@ -34,7 +34,7 @@ static void iio_buffer_cb_release(struct iio_buffer
> > *buffer)
> > {
> > struct iio_cb_buffer *cb_buff = buffer_to_cb_buffer(buffer);
> >
> > - bitmap_free(cb_buff->buffer.scan_mask);
> > + iio_buffer_free_scanmask(&cb_buff->buffer);
> > kfree(cb_buff);
> > }
> >
> > @@ -72,27 +72,26 @@ struct iio_cb_buffer *iio_channel_get_all_cb(struct
> > device *dev,
> > }
> >
> > cb_buff->indio_dev = cb_buff->channels[0].indio_dev;
> > - cb_buff->buffer.scan_mask = bitmap_zalloc(cb_buff->indio_dev-
> > >masklength,
> > - GFP_KERNEL);
> > - if (cb_buff->buffer.scan_mask == NULL) {
> > - ret = -ENOMEM;
> > +
> > + ret = iio_buffer_alloc_scanmask(&cb_buff->buffer,
> > + cb_buff->indio_dev->masklength);
> > + if (ret)
> > goto error_release_channels;
> > - }
> > +
> > chan = &cb_buff->channels[0];
> > while (chan->indio_dev) {
> > if (chan->indio_dev != cb_buff->indio_dev) {
> > ret = -EINVAL;
> > goto error_free_scan_mask;
> > }
> > - set_bit(chan->channel->scan_index,
> > - cb_buff->buffer.scan_mask);
> > + iio_buffer_channel_enable(&cb_buff->buffer, chan);
> > chan++;
> > }
> >
> > return cb_buff;
> >
> > error_free_scan_mask:
> > - bitmap_free(cb_buff->buffer.scan_mask);
> > + iio_buffer_free_scanmask(&cb_buff->buffer);
> > error_release_channels:
> > iio_channel_release_all(cb_buff->channels);
> > error_free_cb_buff:
> > diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-
> > buffer.c
> > index eae39eaf49af..c6b63f4474ff 100644
> > --- a/drivers/iio/industrialio-buffer.c
> > +++ b/drivers/iio/industrialio-buffer.c
> > @@ -208,6 +208,26 @@ void iio_buffer_init(struct iio_buffer *buffer)
> > }
> > EXPORT_SYMBOL(iio_buffer_init);
> >
> > +int iio_buffer_alloc_scanmask(struct iio_buffer *buffer,
> > + unsigned int masklength)
> > +{
> > + if (!masklength)
> > + return -EINVAL;
> > +
> > + buffer->scan_mask = bitmap_zalloc(masklength, GFP_KERNEL);
> > + if (buffer->scan_mask == NULL)
> > + return -ENOMEM;
> > +
> > + return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(iio_buffer_alloc_scanmask);
> > +
> > +void iio_buffer_free_scanmask(struct iio_buffer *buffer)
> > +{
> > + bitmap_free(buffer->scan_mask);
> > +}
> > +EXPORT_SYMBOL_GPL(iio_buffer_free_scanmask);
> > +
> > /**
> > * iio_buffer_set_attrs - Set buffer specific attributes
> > * @buffer: The buffer for which we are setting attributes
> > @@ -1306,14 +1326,10 @@ int iio_buffer_alloc_sysfs_and_mask(struct iio_dev
> > *indio_dev)
> > indio_dev->scan_index_timestamp =
> > channels[i].scan_index;
> > }
> > - if (indio_dev->masklength && buffer->scan_mask == NULL) {
> > - buffer->scan_mask = bitmap_zalloc(indio_dev->masklength,
> > - GFP_KERNEL);
> > - if (buffer->scan_mask == NULL) {
> > - ret = -ENOMEM;
> > - goto error_cleanup_dynamic;
> > - }
> > - }
> > +
> > + ret = iio_buffer_alloc_scanmask(buffer, indio_dev->masklength);
> > + if (ret)
> > + goto error_cleanup_dynamic;
> > }
> >
> > buffer->scan_el_group.name = iio_scan_elements_group_name;
> > @@ -1334,7 +1350,7 @@ int iio_buffer_alloc_sysfs_and_mask(struct iio_dev
> > *indio_dev)
> > return 0;
> >
> > error_free_scan_mask:
> > - bitmap_free(buffer->scan_mask);
> > + iio_buffer_free_scanmask(buffer);
> > error_cleanup_dynamic:
> > iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list);
> > kfree(buffer->buffer_group.attrs);
> > @@ -1349,7 +1365,7 @@ void iio_buffer_free_sysfs_and_mask(struct iio_dev
> > *indio_dev)
> > if (!buffer)
> > return;
> >
> > - bitmap_free(buffer->scan_mask);
> > + iio_buffer_free_scanmask(buffer);
> > kfree(buffer->buffer_group.attrs);
> > kfree(buffer->scan_el_group.attrs);
> > iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list);
> > diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
> > index ede99e0d5371..f35cb9985edc 100644
> > --- a/drivers/iio/inkern.c
> > +++ b/drivers/iio/inkern.c
> > @@ -11,6 +11,7 @@
> >
> > #include <linux/iio/iio.h>
> > #include "iio_core.h"
> > +#include <linux/iio/buffer_impl.h>
> > #include <linux/iio/machine.h>
> > #include <linux/iio/driver.h>
> > #include <linux/iio/consumer.h>
> > @@ -857,6 +858,20 @@ int iio_write_channel_raw(struct iio_channel *chan, int
> > val)
> > }
> > EXPORT_SYMBOL_GPL(iio_write_channel_raw);
> >
> > +void iio_buffer_channel_enable(struct iio_buffer *buffer,
> > + const struct iio_channel *chan)
> > +{
> > + set_bit(chan->channel->scan_index, buffer->scan_mask);
> > +}
> > +EXPORT_SYMBOL_GPL(iio_buffer_channel_enable);
> > +
> > +void iio_buffer_channel_disable(struct iio_buffer *buffer,
> > + const struct iio_channel *chan)
> > +{
> > + clear_bit(chan->channel->scan_index, buffer->scan_mask);
> > +}
> > +EXPORT_SYMBOL_GPL(iio_buffer_channel_disable);
> > +
> > unsigned int iio_get_channel_ext_info_count(struct iio_channel *chan)
> > {
> > const struct iio_chan_spec_ext_info *ext_info;
> > diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h
> > index c4118dcb8e05..9fcd320c2fb4 100644
> > --- a/include/linux/iio/consumer.h
> > +++ b/include/linux/iio/consumer.h
> > @@ -12,6 +12,7 @@
> >
> > struct iio_dev;
> > struct iio_chan_spec;
> > +struct iio_buffer;
> > struct device;
> >
> > /**
> > @@ -342,6 +343,15 @@ int iio_read_channel_scale(struct iio_channel *chan,
> > int *val,
> > int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
> > int *processed, unsigned int scale);
> >
> > +void iio_buffer_channel_enable(struct iio_buffer *buffer,
> > + const struct iio_channel *chan);
> > +void iio_buffer_channel_disable(struct iio_buffer *buffer,
> > + const struct iio_channel *chan);
> > +
> > +int iio_buffer_alloc_scanmask(struct iio_buffer *buffer,
> > + unsigned int masklength);
> > +void iio_buffer_free_scanmask(struct iio_buffer *buffer);
> > +
> > /**
> > * iio_get_channel_ext_info_count() - get number of ext_info attributes
> > * connected to the channel.
