On 19/11/2019 23:19, Mike Leach wrote:
Dynamically adds sysfs attributes for all connections defined in the CTI.
Each connection has a triggers<N> sub-directory with name, in_signals,
in_types, out_signals and out_types as read-only parameters in the
directory. in_ or out_ parameters may be omitted if there are no in or
out signals for the connection.
Additionally each device has a nr_cons in the connections sub-directory.
This allows clients to explore the connection and trigger signal details
without needing to refer to device tree or specification of the device.
Standardised type information is provided for certain common functions -
e.g. snk_full for a trigger from a sink indicating full. Otherwise type
defaults to genio.
Signed-off-by: Mike Leach <mike.leach@xxxxxxxxxx>
---
.../hwtracing/coresight/coresight-cti-sysfs.c | 376 +++++++++++++++++-
drivers/hwtracing/coresight/coresight-cti.c | 13 +-
drivers/hwtracing/coresight/coresight-cti.h | 11 +-
3 files changed, 396 insertions(+), 4 deletions(-)
The patch looks good overall, some minor comments below.
diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
index f800402f73da..91986732506f 100644
--- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c
+++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
@@ -8,6 +8,67 @@
@@ -818,7 +890,306 @@ static struct attribute *coresight_cti_channel_attrs[] = {
NULL,
};
-/* sysfs groups */
+/* Create the connections trigger groups and attrs dynamically */
+/*
+ * Each connection has dynamic group triggers<N> + name, trigin/out sigs/types
+ * attributes, + each device has static nr_trigger_cons giving the number
+ * of groups. e.g. in sysfs:-
+ * /cti_<name>/triggers0
+ * /cti_<name>/triggers1
+ * /cti_<name>/nr_trigger_cons
+ * where nr_trigger_cons = 2
+ */
+static ssize_t con_name_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct dev_ext_attribute *ext_attr =
+ container_of(attr, struct dev_ext_attribute, attr);
+ struct cti_trig_con *con = (struct cti_trig_con *)ext_attr->var;
+
+ return scnprintf(buf, PAGE_SIZE, "%s\n", con->con_dev_name);
+}
+
+static ssize_t trigin_sig_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct dev_ext_attribute *ext_attr =
+ container_of(attr, struct dev_ext_attribute, attr);
+ struct cti_trig_con *con = (struct cti_trig_con *)ext_attr->var;
+ struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ struct cti_config *cfg = &drvdata->config;
+ unsigned long mask = con->con_in->used_mask;
+
+ return bitmap_print_to_pagebuf(true, buf, &mask, cfg->nr_trig_max);
+}
+
+static ssize_t trigout_sig_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct dev_ext_attribute *ext_attr =
+ container_of(attr, struct dev_ext_attribute, attr);
+ struct cti_trig_con *con = (struct cti_trig_con *)ext_attr->var;
+ struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ struct cti_config *cfg = &drvdata->config;
+ unsigned long mask = con->con_out->used_mask;
+
+ return bitmap_print_to_pagebuf(true, buf, &mask, cfg->nr_trig_max);
+}
+
+/* convert a sig type id to a name */
+static const char *
+cti_sig_type_name(struct cti_trig_con *con, int used_count, bool in)
+{
+ int idx = 0;
+ struct cti_trig_grp *grp = in ? con->con_in : con->con_out;
+
+ if (grp->sig_types) {
+ if (used_count < grp->nr_sigs)
+ idx = grp->sig_types[used_count];
+ }
+ return sig_type_names[idx];
+}
+
+static ssize_t trigin_type_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct dev_ext_attribute *ext_attr =
+ container_of(attr, struct dev_ext_attribute, attr);
+ struct cti_trig_con *con = (struct cti_trig_con *)ext_attr->var;
+ int sig_idx, used = 0, b_sz = PAGE_SIZE;
+ const char *name;
+
+ for (sig_idx = 0; sig_idx < con->con_in->nr_sigs; sig_idx++) {
+ name = cti_sig_type_name(con, sig_idx, true);
+ used += scnprintf(buf + used, b_sz - used, "%s ", name);
+ }
+ used += scnprintf(buf + used, b_sz - used, "\n");
+ return used;
+}
+
+static ssize_t trigout_type_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct dev_ext_attribute *ext_attr =
+ container_of(attr, struct dev_ext_attribute, attr);
+ struct cti_trig_con *con = (struct cti_trig_con *)ext_attr->var;
+ int sig_idx, used = 0, b_sz = PAGE_SIZE;
+ const char *name;
+
+ for (sig_idx = 0; sig_idx < con->con_out->nr_sigs; sig_idx++) {
+ name = cti_sig_type_name(con, sig_idx, false);
+ used += scnprintf(buf + used, b_sz - used, "%s ", name);
+ }
+ used += scnprintf(buf + used, b_sz - used, "\n");
+ return used;
+}
+
+/*
+ * Array of show function names declared above to allow selection
+ * for the connection attributes
+ */
+static p_show_fn show_fns[CTI_CON_ATTR_MAX] = {
+ con_name_show,
+ trigin_sig_show,
+ trigout_sig_show,
+ trigin_type_show,
+ trigout_type_show,
+};
+
+static int cti_create_con_sysfs_attr(struct cti_trig_con *con,
+ enum cti_conn_attr_type attr_type,
+ int attr_idx)
+{
+ struct dev_ext_attribute *dev_ext_attr = 0;
super minor nit: You may use "eattr" instead.
+ char *name = 0;
+
+ dev_ext_attr = kzalloc(sizeof(struct dev_ext_attribute), GFP_KERNEL);
Could we not use devm_* alloc helpers everywhere ?
+ if (dev_ext_attr) {
+ name = kstrdup(con_attr_names[attr_type], GFP_KERNEL);
+ if (name) {
+ /* fill out the underlying attribute struct */
+ dev_ext_attr->attr.attr.name = name;
+ dev_ext_attr->attr.attr.mode = 0444;
+
+ /* now the device_attribute struct */
+ dev_ext_attr->attr.show = show_fns[attr_type];
+ } else {
+ kfree(dev_ext_attr);
+ return -ENOMEM;
+ }
+ } else {
+ return -ENOMEM;
+ }
+ dev_ext_attr->var = con;
+ con->con_attrs[attr_idx] = &dev_ext_attr->attr.attr;
+ return 0;
+}
+
+static struct attribute_group *
+cti_create_con_sysfs_group(struct cti_device *ctidev, int con_idx,
+ struct cti_trig_con *con)
+{
+ struct attribute_group *group = NULL;
+
+ group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL);
+ if (!group)
+ return NULL;
+
+ group->name = kasprintf(GFP_KERNEL, "triggers%d", con_idx);
+ if (!group->name) {
+ kfree(group);
+ return NULL;
+ }
+
+ ctidev->con_groups[con_idx + CORESIGHT_CTI_STATIC_GROUPS_MAX - 1]
+ = group;
nit:
con_idx += CORESIGHT_CTI_STATIC_GROUPS_MAX - 1;
ctidev->con_groups[con_idx] = group;
+ con->attr_group = group;
+ return group;
+}
+
+/* create a triggers connection group and the attributes for that group */
+static int cti_create_con_attr_set(int con_idx, struct cti_device *ctidev,
+ struct cti_trig_con *con)
+{
+ struct attribute_group *attr_group = NULL;
+ int attr_idx = 0;
+ int err = -ENOMEM;
+
+ attr_group = cti_create_con_sysfs_group(ctidev, con_idx, con);
+ if (!attr_group)
+ return -ENOMEM;
+
+ /* allocate NULL terminated array of attributes */
+ con->con_attrs = kcalloc(CTI_CON_ATTR_MAX + 1,
+ sizeof(struct attribute *),
+ GFP_KERNEL);
Again why not devm_* allocations ? That takes the pain of freeing the
memory away and helps prevent memory leaks.
+ if (!con->con_attrs)
+ return -ENOMEM;
+
+ err = cti_create_con_sysfs_attr(con, CTI_CON_ATTR_NAME, attr_idx++);
+ if (err)
+ return err;
+
+ if (con->con_in->nr_sigs > 0) {
+ err = cti_create_con_sysfs_attr(con, CTI_CON_ATTR_TRIGIN_SIG,
+ attr_idx++);
+ if (err)
+ return err;
+
+ err = cti_create_con_sysfs_attr(con, CTI_CON_ATTR_TRIGIN_TYPES,
+ attr_idx++);
+ if (err)
+ return err;
+ }
+
+ if (con->con_in->nr_sigs > 0) {
+ err = cti_create_con_sysfs_attr(con, CTI_CON_ATTR_TRIGOUT_SIG,
+ attr_idx++);
+ if (err)
+ return err;
+
+ err = cti_create_con_sysfs_attr(con, CTI_CON_ATTR_TRIGOUT_TYPES,
+ attr_idx++);
+ if (err)
+ return err;
+ }
+ attr_group->attrs = con->con_attrs;
+ return 0;
+}
+
+/* create the array of group pointers for the CTI sysfs groups */
+int cti_create_cons_groups(struct cti_device *ctidev)
+{
+ int i, nr_groups;
+
+ /* nr groups - dynamic + static + NULL terminator */
+ nr_groups = ctidev->nr_trig_con + CORESIGHT_CTI_STATIC_GROUPS_MAX;
+ ctidev->con_groups = kcalloc(nr_groups,
+ sizeof(struct attribute_group *),
+ GFP_KERNEL);
+ if (!ctidev->con_groups)
+ return -ENOMEM;
+
+ /* populate first locations with the static set of groups */
+ for (i = 0; i < (CORESIGHT_CTI_STATIC_GROUPS_MAX - 1); i++)
+ ctidev->con_groups[i] = coresight_cti_groups[i];
+
+ return 0;
+}
+
To be frank, it doesn't make sense to have this split of populating
the groups.
+int cti_create_cons_sysfs(struct cti_drvdata *drvdata)
+{
+ struct cti_device *ctidev = &drvdata->ctidev;
+ int err, con_idx = 0;
+ struct cti_trig_con *tc = NULL;
+
+ err = cti_create_cons_groups(ctidev);
+ if (err)
+ return err;
+
+ /* add dynamic set for each connection */
+ list_for_each_entry(tc, &ctidev->trig_cons, node) {
+ err = cti_create_con_attr_set(con_idx++, ctidev, tc);
+ if (err)
+ goto cons_sysfs_err;
+ }
+ return 0;
+
+cons_sysfs_err:
+ cti_destroy_cons_sysfs(ctidev);
+ return err;
+}
+
+void cti_free_con_attr(struct attribute *con_attr)
+{
+ struct device_attribute *dattr =
+ container_of(con_attr, struct device_attribute, attr);
+ struct dev_ext_attribute *dev_ext_attr =
+ container_of(dattr, struct dev_ext_attribute, attr);
+ kfree(con_attr->name);
+ kfree(dev_ext_attr);
+}
+
+void cti_free_con_group(struct attribute_group *attr_group)
+{
+ if (attr_group) {
+ kfree(attr_group->name);
+ kfree(attr_group);
+ }
+}
+
+void cti_destroy_cons_attr_set(int con_idx, struct cti_device *ctidev,
+ struct cti_trig_con *con)
+{
+ int i;
+
+ if (con->con_attrs) {
+ for (i = 0; i < CTI_CON_ATTR_MAX; i++) {
+ if (con->con_attrs[i])
+ cti_free_con_attr(con->con_attrs[i]);
+ }
+ kfree(con->con_attrs);
+ }
+ cti_free_con_group(con->attr_group);
+}
+
+void cti_destroy_cons_sysfs(struct cti_device *ctidev)
+{
+ struct cti_trig_con *tc;
minor nit: Please keep the variable name consistent if possible, helps a
lot with the code following. i.e, tc vs con above in
cti_destroy_cons_attr_set().
+ int con_idx = 0;
+
+ list_for_each_entry(tc, &ctidev->trig_cons, node) {
+ cti_destroy_cons_attr_set(con_idx++, ctidev, tc);
+ }
+ kfree(ctidev->con_groups);
+}
+
+/* attribute and group sysfs tables. */
static const struct attribute_group coresight_cti_group = {
.attrs = coresight_cti_attrs,
};
@@ -838,7 +1209,8 @@ static const struct attribute_group coresight_cti_channels_group = {
.name = "channels",
};
-const struct attribute_group *coresight_cti_groups[] = {
+const struct attribute_group *
+coresight_cti_groups[CORESIGHT_CTI_STATIC_GROUPS_MAX] = {
&coresight_cti_group,
&coresight_cti_mgmt_group,
&coresight_cti_regs_group,
diff --git a/drivers/hwtracing/coresight/coresight-cti.c b/drivers/hwtracing/coresight/coresight-cti.c
index cf116463149a..c3d63cc53bdd 100644
--- a/drivers/hwtracing/coresight/coresight-cti.c
+++ b/drivers/hwtracing/coresight/coresight-cti.c
@@ -561,6 +561,9 @@ static void cti_device_release(struct device *dev)
mutex_lock(&ect_mutex);
+ /* clear the dynamic sysfs associate with connections */
+ cti_destroy_cons_sysfs(&drvdata->ctidev);
+
/* remove from the list */
list_for_each_entry_safe(ect_item, ect_tmp, &ect_net, node) {
if (ect_item == drvdata) {
@@ -636,12 +639,20 @@ static int cti_probe(struct amba_device *adev, const struct amba_id *id)
goto err_out;
}
+ /* create dynamic attributes for connections */
+ ret = cti_create_cons_sysfs(drvdata);
+ if (ret) {
+ pr_err("%s: create dynamic sysfs entries failed\n",
+ cti_desc.name);
nit: It may be a good idea to include the actual device name (rather
than just cti_xxx). so may be :
dev_err(dev, "%s:....", cti_desc.name) ?
+ goto err_out;
+ }
Except for the devm_ alloc question, rest are fine.
Suzuki
