On Fri, 24 Apr 2020 08:18:15 +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.
>
> Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
Hi Alex,
For some reason I only have patch 1 of this series of 4.
This one looks reasonable to me as abstracts away how it is implemented
which is good. A few comments and a question inline.
Jonathan
> ---
> 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, 58 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/iio/buffer/industrialio-buffer-cb.c b/drivers/iio/buffer/industrialio-buffer-cb.c
> index 47c96f7f4976..b50f1f48cac6 100644
> --- a/drivers/iio/buffer/industrialio-buffer-cb.c
> +++ b/drivers/iio/buffer/industrialio-buffer-cb.c
> @@ -33,8 +33,7 @@ static int iio_buffer_cb_store_to(struct iio_buffer *buffer, const void *data)
> 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(buffer);
> kfree(cb_buff);
> }
>
> @@ -72,27 +71,25 @@ 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);
> + 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 221157136af6..c06691281287 100644
> --- a/drivers/iio/industrialio-buffer.c
> +++ b/drivers/iio/industrialio-buffer.c
> @@ -206,6 +206,26 @@ void iio_buffer_init(struct iio_buffer *buffer)
> }
> EXPORT_SYMBOL(iio_buffer_init);
>
> +int iio_buffer_alloc_scanmask(struct iio_buffer *buffer,
> + struct iio_dev *indio_dev)
I'm not sure passing the indio_dev in here makes sense as it
obscures that all we are getting from it is the masklength.
May be better to pass that explicitly.
> +{
> + if (!indio_dev->masklength)
> + return 0;
This is a bit of an oddity of the old code. Any idea why we
allow things to continue with a masklength of 0? Seems to me
that it is thoroughly broken if that occurs!
> +
> + buffer->scan_mask = bitmap_zalloc(indio_dev->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
> @@ -1301,14 +1321,10 @@ 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);
> + if (ret)
> + goto error_cleanup_dynamic;
> }
>
> buffer->scan_el_group.name = iio_scan_elements_group_name;
> @@ -1329,7 +1345,7 @@ 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(indio_dev->buffer->buffer_group.attrs);
> @@ -1342,7 +1358,7 @@ void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev)
> if (!indio_dev->buffer)
> return;
>
> - bitmap_free(indio_dev->buffer->scan_mask);
> + iio_buffer_free_scanmask(indio_dev->buffer);
> kfree(indio_dev->buffer->buffer_group.attrs);
> kfree(indio_dev->buffer->scan_el_group.attrs);
> iio_free_chan_devattr_list(&indio_dev->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..dbc87c26250a 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,
> + struct iio_dev *indio_dev);
> +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.
