On Sat, 10 Jul 2021 12:06:53 -0500
David Lechner <david@xxxxxxxxxxxxxx> wrote:
> On 7/5/21 3:19 AM, William Breathitt Gray wrote:
> > The Generic Counter chrdev interface expects users to supply component
> > IDs in order to select extensions for requests. In order for users to
> > know what component ID belongs to which extension this information must
> > be exposed. The *_component_id attribute provides a way for users to
> > discover what component ID belongs to which respective extension.
> >
> > Cc: David Lechner <david@xxxxxxxxxxxxxx>
> > Cc: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
> > Cc: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > Signed-off-by: William Breathitt Gray <vilhelm.gray@xxxxxxxxx>
> > ---
> > Documentation/ABI/testing/sysfs-bus-counter | 16 ++++++++++-
> > drivers/counter/counter-sysfs.c | 30 ++++++++++++++++-----
> > 2 files changed, 39 insertions(+), 7 deletions(-)
> >
> > diff --git a/Documentation/ABI/testing/sysfs-bus-counter b/Documentation/ABI/testing/sysfs-bus-counter
> > index 9809d8a47431..e0e99adb0ecc 100644
> > --- a/Documentation/ABI/testing/sysfs-bus-counter
> > +++ b/Documentation/ABI/testing/sysfs-bus-counter
> > @@ -203,12 +203,26 @@ Description:
> > both edges:
> > Any state transition.
> >
> > +What: /sys/bus/counter/devices/counterX/countY/ceiling_component_id
> > +What: /sys/bus/counter/devices/counterX/countY/floor_component_id
> > +What: /sys/bus/counter/devices/counterX/countY/count_mode_component_id
> > +What: /sys/bus/counter/devices/counterX/countY/direction_component_id
> > +What: /sys/bus/counter/devices/counterX/countY/enable_component_id
> > +What: /sys/bus/counter/devices/counterX/countY/error_noise_component_id
> > +What: /sys/bus/counter/devices/counterX/countY/prescaler_component_id
> > +What: /sys/bus/counter/devices/counterX/countY/preset_component_id
> > +What: /sys/bus/counter/devices/counterX/countY/preset_enable_component_id
> > What: /sys/bus/counter/devices/counterX/countY/signalZ_action_component_id
> > +What: /sys/bus/counter/devices/counterX/signalY/cable_fault_component_id
> > +What: /sys/bus/counter/devices/counterX/signalY/cable_fault_enable_component_id
> > +What: /sys/bus/counter/devices/counterX/signalY/filter_clock_prescaler_component_id
> > +What: /sys/bus/counter/devices/counterX/signalY/index_polarity_component_id
> > +What: /sys/bus/counter/devices/counterX/signalY/synchronous_mode_component_id
>
> Could we just write a single line?
>
> What: /sys/bus/counter/devices/counterX/signalY/<component>_component_id
Not nice for grepping so I think it's better to call them out explicitly.
There has been a proposal to check this ABI doc against running kernels, and if we have
too many wild cards that becomes very difficult to do.
Jonathan
>
> > KernelVersion: 5.15
> > Contact: linux-iio@xxxxxxxxxxxxxxx
> > Description:
> > Read-only attribute that indicates the component ID of the
> > - respective Synapse of Count Y for Signal Z.
> > + respective extension or Synapse.
> >
> > What: /sys/bus/counter/devices/counterX/countY/spike_filter_ns
> > KernelVersion: 5.14
> > diff --git a/drivers/counter/counter-sysfs.c b/drivers/counter/counter-sysfs.c
> > index bb49a10f160b..eb1505bfbd89 100644
> > --- a/drivers/counter/counter-sysfs.c
> > +++ b/drivers/counter/counter-sysfs.c
> > @@ -587,6 +587,7 @@ static int counter_signal_attrs_create(struct counter_device *const counter,
> > int err;
> > struct counter_comp comp;
> > size_t i;
> > + struct counter_comp *ext;
> >
> > /* Create main Signal attribute */
> > comp = counter_signal_comp;
> > @@ -602,8 +603,13 @@ static int counter_signal_attrs_create(struct counter_device *const counter,
> >
> > /* Create an attribute for each extension */
> > for (i = 0; i < signal->num_ext; i++) {
> > - err = counter_attr_create(dev, group, signal->ext + i, scope,
> > - signal);
> > + ext = signal->ext + i;
> > +
> > + err = counter_attr_create(dev, group, ext, scope, signal);
> > + if (err < 0)
> > + return err;
> > +
> > + err = counter_comp_id_attr_create(dev, group, ext->name, i);
> > if (err < 0)
> > return err;
> > }
> > @@ -694,6 +700,7 @@ static int counter_count_attrs_create(struct counter_device *const counter,
> > int err;
> > struct counter_comp comp;
> > size_t i;
> > + struct counter_comp *ext;
> >
> > /* Create main Count attribute */
> > comp = counter_count_comp;
> > @@ -718,8 +725,13 @@ static int counter_count_attrs_create(struct counter_device *const counter,
> >
> > /* Create an attribute for each extension */
> > for (i = 0; i < count->num_ext; i++) {
> > - err = counter_attr_create(dev, group, count->ext + i, scope,
> > - count);
> > + ext = count->ext + i;
>
> ext = &count->ext[i];
>
> Could make it more clear we are dealing with pointers rather than integers.
>
> > +
> > + err = counter_attr_create(dev, group, ext, scope, count);
> > + if (err < 0)
> > + return err;
> > +
> > + err = counter_comp_id_attr_create(dev, group, ext->name, i);
> > if (err < 0)
> > return err;
> > }
> > @@ -783,6 +795,7 @@ static int counter_sysfs_attr_add(struct counter_device *const counter,
> > struct device *const dev = &counter->dev;
> > int err;
> > size_t i;
> > + struct counter_comp *ext;
> >
> > /* Add Signals sysfs attributes */
> > err = counter_sysfs_signals_add(counter, group);
> > @@ -815,8 +828,13 @@ static int counter_sysfs_attr_add(struct counter_device *const counter,
> >
> > /* Create an attribute for each extension */
> > for (i = 0; i < counter->num_ext; i++) {
> > - err = counter_attr_create(dev, group, counter->ext + i, scope,
> > - NULL);
> > + ext = counter->ext + i;
>
> ditto
>
> > +
> > + err = counter_attr_create(dev, group, ext, scope, NULL);
> > + if (err < 0)
> > + return err;
> > +
> > + err = counter_comp_id_attr_create(dev, group, ext->name, i);
> > if (err < 0)
> > return err;
> > }
> >
>
