Changes in v3:
- Fix array length overwrite by allocating space for each array element
- Add support for counter array component reads from Counter chrdev
The COUNTER_COMP_ARRAY Counter component type is introduced to enable
support for Counter array components. With Counter array components,
exposure for buffers on counter devices can be defined via new Counter
array component macros. This should simplify code for driver authors who
would otherwise need to define individual Counter components for each
array element.
Driver authors can handle reads/writes for an array component by
receiving an element index via the `idx` parameter and processing the
respective value via the `val` parameter.
For example, suppose a driver wants to expose a Count's read-only
capture buffer of four elements using a callback
`foobar_capture_read()`::
DEFINE_COUNTER_ARRAY(foobar_capture_array, COUNTER_COMP_U64,
NULL, 4)
COUNTER_COMP_COUNT_ARRAY_U64("capture", foobar_capture_read,
NULL, foobar_capture_array)
Respective sysfs attributes for each array element would appear for the
respective Count:
* /sys/bus/counter/devices/counterX/countY/capture0
* /sys/bus/counter/devices/counterX/countY/capture1
* /sys/bus/counter/devices/counterX/countY/capture2
* /sys/bus/counter/devices/counterX/countY/capture3
If a user tries to read _capture2_ for example, `idx` will be `2` when
passed to the `foobar_capture_read()` callback, and thus the driver
knows which array element to handle.
In addition, this patchset introduces the Signal polarity component,
which represents the active level of a respective Signal. There are two
possible states: positive (rising edge) and negative (falling edge). The
104-quad-8 driver is updated to expose its index_polarity functionality
via this new polarity component.
A macro COUNTER_COMP_ARRAY_POLARITY() is provided for driver authors to
support Counter arrays of Signal polarity component type;
DEFINE_COUNTER_AVAILABLE may be used to define the polarity modes that
are passed to DEFINE_COUNTER_ARRAY. The only component types supported
for Counter arrays currently are COUNTER_COMP_U64 and
COUNTER_COMP_SIGNAL_POLARITY.
William Breathitt Gray (4):
counter: Introduce the Signal polarity component
counter: 104-quad-8: Add Signal polarity component
counter: Consolidate Counter extension sysfs attribute creation
counter: Introduce the COUNTER_COMP_ARRAY component type
Documentation/ABI/testing/sysfs-bus-counter | 13 +
drivers/counter/104-quad-8.c | 35 +++
drivers/counter/counter-chrdev.c | 47 ++-
drivers/counter/counter-sysfs.c | 303 ++++++++++++++++----
include/linux/counter.h | 131 +++++++++
include/uapi/linux/counter.h | 6 +
6 files changed, 483 insertions(+), 52 deletions(-)
base-commit: a12224997bec72d231a8dd642876e6364decdc45
--
2.37.3
Counter extensions are handled for the Device, Counts, and Signals. The
code loops through each Counter extension and creates the expected sysfs
attributes. This patch consolidates that code into functions to reduce
redundancy and make the intention of the code clearer.
Signed-off-by: William Breathitt Gray <[email protected]>
---
drivers/counter/counter-sysfs.c | 98 ++++++++++++++++-----------------
1 file changed, 49 insertions(+), 49 deletions(-)
diff --git a/drivers/counter/counter-sysfs.c b/drivers/counter/counter-sysfs.c
index 92d3d4f549cb..7ce7c51395da 100644
--- a/drivers/counter/counter-sysfs.c
+++ b/drivers/counter/counter-sysfs.c
@@ -591,6 +591,46 @@ static int counter_comp_id_attr_create(struct device *const dev,
return 0;
}
+static int counter_ext_attrs_create(struct device *const dev,
+ struct counter_attribute_group *const group,
+ const struct counter_comp *const ext,
+ const enum counter_scope scope,
+ void *const parent, const size_t id)
+{
+ int err;
+
+ /* Create main extension attribute */
+ err = counter_attr_create(dev, group, ext, scope, parent);
+ if (err < 0)
+ return err;
+
+ /* Create extension id attribute */
+ return counter_comp_id_attr_create(dev, group, ext->name, id);
+}
+
+static int counter_sysfs_exts_add(struct device *const dev,
+ struct counter_attribute_group *const group,
+ const struct counter_comp *const exts,
+ const size_t num_ext,
+ const enum counter_scope scope,
+ void *const parent)
+{
+ size_t i;
+ const struct counter_comp *ext;
+ int err;
+
+ /* Create attributes for each extension */
+ for (i = 0; i < num_ext; i++) {
+ ext = &exts[i];
+ err = counter_ext_attrs_create(dev, group, ext, scope, parent,
+ i);
+ if (err < 0)
+ return err;
+ }
+
+ return 0;
+}
+
static struct counter_comp counter_signal_comp = {
.type = COUNTER_COMP_SIGNAL_LEVEL,
.name = "signal",
@@ -604,8 +644,6 @@ static int counter_signal_attrs_create(struct counter_device *const counter,
struct device *const dev = &counter->dev;
int err;
struct counter_comp comp;
- size_t i;
- struct counter_comp *ext;
/* Create main Signal attribute */
comp = counter_signal_comp;
@@ -619,21 +657,9 @@ static int counter_signal_attrs_create(struct counter_device *const counter,
if (err < 0)
return err;
- /* Create an attribute for each extension */
- for (i = 0; i < signal->num_ext; i++) {
- ext = &signal->ext[i];
-
- err = counter_attr_create(dev, cattr_group, ext, scope, signal);
- if (err < 0)
- return err;
-
- err = counter_comp_id_attr_create(dev, cattr_group, ext->name,
- i);
- if (err < 0)
- return err;
- }
-
- return 0;
+ /* Add Signal extensions */
+ return counter_sysfs_exts_add(dev, cattr_group, signal->ext,
+ signal->num_ext, scope, signal);
}
static int counter_sysfs_signals_add(struct counter_device *const counter,
@@ -718,8 +744,6 @@ static int counter_count_attrs_create(struct counter_device *const counter,
struct device *const dev = &counter->dev;
int err;
struct counter_comp comp;
- size_t i;
- struct counter_comp *ext;
/* Create main Count attribute */
comp = counter_count_comp;
@@ -742,21 +766,9 @@ static int counter_count_attrs_create(struct counter_device *const counter,
if (err < 0)
return err;
- /* Create an attribute for each extension */
- for (i = 0; i < count->num_ext; i++) {
- ext = &count->ext[i];
-
- err = counter_attr_create(dev, cattr_group, ext, scope, count);
- if (err < 0)
- return err;
-
- err = counter_comp_id_attr_create(dev, cattr_group, ext->name,
- i);
- if (err < 0)
- return err;
- }
-
- return 0;
+ /* Add Count extensions */
+ return counter_sysfs_exts_add(dev, cattr_group, count->ext,
+ count->num_ext, scope, count);
}
static int counter_sysfs_counts_add(struct counter_device *const counter,
@@ -849,8 +861,6 @@ static int counter_sysfs_attr_add(struct counter_device *const counter,
const enum counter_scope scope = COUNTER_SCOPE_DEVICE;
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, cattr_group);
@@ -887,19 +897,9 @@ static int counter_sysfs_attr_add(struct counter_device *const counter,
if (err < 0)
return err;
- /* Create an attribute for each extension */
- for (i = 0; i < counter->num_ext; i++) {
- ext = &counter->ext[i];
-
- err = counter_attr_create(dev, cattr_group, ext, scope, NULL);
- if (err < 0)
- return err;
-
- err = counter_comp_id_attr_create(dev, cattr_group, ext->name,
- i);
- if (err < 0)
- return err;
- }
+ /* Add device extensions */
+ return counter_sysfs_exts_add(dev, cattr_group, counter->ext,
+ counter->num_ext, scope, NULL);
return 0;
}
--
2.37.3
The 104-quad-8 driver provides support for Index signal polarity modes
via the "index_polarity" Signal component. This patch exposes the same
functionality through the more standard "polarity" Signal component.
Signed-off-by: William Breathitt Gray <[email protected]>
---
drivers/counter/104-quad-8.c | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)
diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c
index 1323edfbe40c..2a9d8259ed4b 100644
--- a/drivers/counter/104-quad-8.c
+++ b/drivers/counter/104-quad-8.c
@@ -549,6 +549,32 @@ static int quad8_index_polarity_set(struct counter_device *counter,
return 0;
}
+static int quad8_polarity_read(struct counter_device *counter,
+ struct counter_signal *signal,
+ enum counter_signal_polarity *polarity)
+{
+ int err;
+ u32 index_polarity;
+
+ err = quad8_index_polarity_get(counter, signal, &index_polarity);
+ if (err)
+ return err;
+
+ *polarity = (index_polarity) ? COUNTER_SIGNAL_POLARITY_POSITIVE :
+ COUNTER_SIGNAL_POLARITY_NEGATIVE;
+
+ return 0;
+}
+
+static int quad8_polarity_write(struct counter_device *counter,
+ struct counter_signal *signal,
+ enum counter_signal_polarity polarity)
+{
+ const u32 pol = (polarity == COUNTER_SIGNAL_POLARITY_POSITIVE) ? 1 : 0;
+
+ return quad8_index_polarity_set(counter, signal, pol);
+}
+
static const char *const quad8_synchronous_modes[] = {
"non-synchronous",
"synchronous"
@@ -977,6 +1003,13 @@ static struct counter_comp quad8_signal_ext[] = {
quad8_signal_fck_prescaler_write)
};
+static const enum counter_signal_polarity quad8_polarities[] = {
+ COUNTER_SIGNAL_POLARITY_POSITIVE,
+ COUNTER_SIGNAL_POLARITY_NEGATIVE,
+};
+
+static DEFINE_COUNTER_AVAILABLE(quad8_polarity_available, quad8_polarities);
+
static DEFINE_COUNTER_ENUM(quad8_index_pol_enum, quad8_index_polarity_modes);
static DEFINE_COUNTER_ENUM(quad8_synch_mode_enum, quad8_synchronous_modes);
@@ -984,6 +1017,8 @@ static struct counter_comp quad8_index_ext[] = {
COUNTER_COMP_SIGNAL_ENUM("index_polarity", quad8_index_polarity_get,
quad8_index_polarity_set,
quad8_index_pol_enum),
+ COUNTER_COMP_POLARITY(quad8_polarity_read, quad8_polarity_write,
+ quad8_polarity_available),
COUNTER_COMP_SIGNAL_ENUM("synchronous_mode", quad8_synchronous_mode_get,
quad8_synchronous_mode_set,
quad8_synch_mode_enum),
--
2.37.3