[RFC PATCH v3 7/9] coresight: syscfg: Add initial configfs support.
Mathieu Poirier
mathieu.poirier at linaro.org
Tue Nov 24 15:57:32 EST 2020
On Fri, Oct 30, 2020 at 05:56:53PM +0000, Mike Leach wrote:
> Adds configfs subsystem and attributes to the configuration manager
> to enable the listing of loaded configurations and features.
>
> The default values of feature parameters can be accessed and altered
> from these attributes to affect all installed devices using the feature.
>
Please no dot (.) at the end of the title. The same goes for 9/9.
> Signed-off-by: Mike Leach <mike.leach at linaro.org>
> ---
> drivers/hwtracing/coresight/Makefile | 2 +-
> .../hwtracing/coresight/coresight-config.c | 2 +
> .../hwtracing/coresight/coresight-config.h | 5 +-
> .../coresight/coresight-syscfg-configfs.c | 418 ++++++++++++++++++
> .../coresight/coresight-syscfg-configfs.h | 47 ++
> .../hwtracing/coresight/coresight-syscfg.c | 31 ++
> .../hwtracing/coresight/coresight-syscfg.h | 4 +
> 7 files changed, 507 insertions(+), 2 deletions(-)
> create mode 100644 drivers/hwtracing/coresight/coresight-syscfg-configfs.c
> create mode 100644 drivers/hwtracing/coresight/coresight-syscfg-configfs.h
>
> diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
> index 9de5586cfd1a..4ec226c44f5b 100644
> --- a/drivers/hwtracing/coresight/Makefile
> +++ b/drivers/hwtracing/coresight/Makefile
> @@ -5,7 +5,7 @@
> obj-$(CONFIG_CORESIGHT) += coresight.o
> coresight-y := coresight-core.o coresight-etm-perf.o coresight-platform.o \
> coresight-sysfs.o coresight-syscfg.o coresight-config.o \
> - coresight-cfg-preload.o
> + coresight-cfg-preload.o coresight-syscfg-configfs.o
> obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o
> coresight-tmc-y := coresight-tmc-core.o coresight-tmc-etf.o \
> coresight-tmc-etr.o
> diff --git a/drivers/hwtracing/coresight/coresight-config.c b/drivers/hwtracing/coresight/coresight-config.c
> index d911e0f083c1..04e7cb4ff769 100644
> --- a/drivers/hwtracing/coresight/coresight-config.c
> +++ b/drivers/hwtracing/coresight/coresight-config.c
> @@ -111,8 +111,10 @@ static void cscfg_reset_feat(struct cscfg_feature_csdev *feat)
> * set the default values for all parameters and regs from the
> * relevant static descriptors.
> */
> + spin_lock(&feat->desc->param_lock);
> for (i = 0; i < feat->nr_params; i++)
> feat->params[i].current_value = feat->desc->params[i].value;
> + spin_unlock(&feat->desc->param_lock);
>
> for (i = 0; i < feat->nr_regs; i++) {
> reg_desc = &feat->desc->regs[i];
> diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h
> index 372f29a59688..39fcac011aa0 100644
> --- a/drivers/hwtracing/coresight/coresight-config.h
> +++ b/drivers/hwtracing/coresight/coresight-config.h
> @@ -7,6 +7,7 @@
> #ifndef _CORESIGHT_CORESIGHT_CONFIG_H
> #define _CORESIGHT_CORESIGHT_CONFIG_H
>
> +#include <linux/configfs.h>
I don't see a need for that header file.
> #include <linux/coresight.h>
> #include <linux/types.h>
>
> @@ -89,6 +90,7 @@ struct cscfg_regval {
> * @match_flags: matching information if loading into a device
> * @nr_params: number of parameters used.
> * @params: array of parameters used.
> + * @param_lock: protect params when accessing default values.
> * @nr_regs: number of registers used.
> * @reg: array of registers used.
> */
> @@ -99,6 +101,7 @@ struct cscfg_feature_desc {
> u32 match_flags;
> int nr_params;
> struct cscfg_parameter_desc *params;
> + spinlock_t param_lock;
I'll skip over this for now but all these locks are increasing the potential of
making the lockdep mechanic very angry, if it hasn't already done so.
> int nr_regs;
> struct cscfg_regval *regs;
> };
> @@ -239,7 +242,7 @@ struct cscfg_feat_ops {
> * @ops: standard ops to enable and disable features on devices.
> */
> struct cscfg_feature_csdev {
> - const struct cscfg_feature_desc *desc;
> + struct cscfg_feature_desc *desc;
Please don't change what has aleady been added. Simply skip the 'const' when
you first introduce the structure.
> struct coresight_device *csdev;
> struct list_head node;
> spinlock_t *csdev_spinlock;
> diff --git a/drivers/hwtracing/coresight/coresight-syscfg-configfs.c b/drivers/hwtracing/coresight/coresight-syscfg-configfs.c
> new file mode 100644
> index 000000000000..ff7ea678100a
> --- /dev/null
> +++ b/drivers/hwtracing/coresight/coresight-syscfg-configfs.c
> @@ -0,0 +1,418 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2020 Linaro Limited, All rights reserved.
> + * Author: Mike Leach <mike.leach at linaro.org>
> + */
> +
> +#include <linux/configfs.h>
> +
> +#include "coresight-syscfg-configfs.h"
> +
> +/*
> + * configfs support for syscfg device.
> + *
> + * config fs is used to manage configurations and features on the
> + * coresight system.
> + */
> +
> +static struct cscfg_device *cscfg_fs_get_cscfg_dev(void);
> +
> +static struct device *cscfg_dev_to_dev(void)
> +{
> + return cscfg_fs_get_cscfg_dev() ? &cscfg_fs_get_cscfg_dev()->dev : NULL;
> +}
> +
> +/*
> + * Declare the subsystem - with base attributes allowing listing of
> + * loaded configurations
> + */
> +static inline struct cscfg_fs_config *to_cscfg_fs_config_group(struct config_group *group)
> +{
> + return container_of(group, struct cscfg_fs_config, group);
> +}
> +
> +/* configurations sub-group */
> +
> +/* attributes for the config view group */
> +static ssize_t cscfg_cfg_description_show(struct config_item *item, char *page)
> +{
> + struct cscfg_fs_config *fs_config = to_cscfg_fs_config_group(to_config_group(item));
> +
> + return scnprintf(page, PAGE_SIZE, "%s\n", fs_config->desc->brief);
> +}
> +CONFIGFS_ATTR_RO(cscfg_cfg_, description);
> +
> +static ssize_t cscfg_cfg_refs_show(struct config_item *item, char *page)
> +{
> + struct cscfg_fs_config *fs_config = to_cscfg_fs_config_group(to_config_group(item));
> + const struct cscfg_config_desc *desc = fs_config->desc;
> + ssize_t ch_used = 0;
> + int i;
> +
> + if (desc->nr_refs) {
> + ch_used += scnprintf(page, PAGE_SIZE, "references %d features:-\n", desc->nr_refs);
> + for (i = 0; i < desc->nr_refs; i++) {
> + ch_used += scnprintf(page + ch_used, PAGE_SIZE - ch_used,
> + "%s\n", desc->refs[i].name);
> + }
> + } else
> + ch_used = scnprintf(page, PAGE_SIZE, "no features referenced\n");
> + return ch_used;
> +}
> +CONFIGFS_ATTR_RO(cscfg_cfg_, refs);
> +
> +static ssize_t cscfg_cfg_nr_presets_show(struct config_item *item, char *page)
> +{
> + struct cscfg_fs_config *fs_config = to_cscfg_fs_config_group(to_config_group(item));
> +
> + return scnprintf(page, PAGE_SIZE, "%d\n", fs_config->desc->nr_presets);
> +}
> +CONFIGFS_ATTR_RO(cscfg_cfg_, nr_presets);
> +
> +static ssize_t cscfg_cfg_preset_values_show(struct config_item *item, char *page)
> +{
> + struct cscfg_fs_config *fs_config = to_cscfg_fs_config_group(to_config_group(item));
> + const struct cscfg_config_desc *cfg = fs_config->desc;
> + const struct cscfg_feature_desc *feat;
> + ssize_t used = 0;
> + int i, j, val_idx, preset_idx;
> +
> + if (!fs_config->desc->nr_presets)
> + return scnprintf(page, PAGE_SIZE, "No presets defined\n");
> +
> + used = scnprintf(page, PAGE_SIZE, "%d presets, %d parameters per preset\n",
> + fs_config->desc->nr_presets, cfg->nr_total_params);
> +
> + for (preset_idx = 0; preset_idx < fs_config->desc->nr_presets; preset_idx++) {
> + /* start index on the correct array line */
> + val_idx = cfg->nr_total_params * preset_idx;
> +
> + /* preset indexes are used as 1 based by the user */
> + used += scnprintf(page + used, PAGE_SIZE - used, "preset[%d]: ", preset_idx+1);
> +
> + /*
> + * A set of presets is the sum of all params in used features,
> + * in order of declaration of features and params in the features
> + */
> + for (i = 0; i < cfg->nr_refs; i++) {
> + feat = cscfg_get_named_feat_desc(cfg->refs[i].name);
> + for (j = 0; j < cfg->refs[i].nr_params; j++) {
> + used += scnprintf(page + used, PAGE_SIZE - used,
> + "%s.%s = 0x%llx ",
> + cfg->refs[i].name, feat->params[j].name,
> + cfg->presets[val_idx++]);
> + }
> + }
> + used += scnprintf(page + used, PAGE_SIZE - used, "\n");
> + }
> + return used;
> +}
> +CONFIGFS_ATTR_RO(cscfg_cfg_, preset_values);
> +
> +static struct configfs_attribute *cscfg_config_view_attrs[] = {
> + &cscfg_cfg_attr_description,
> + &cscfg_cfg_attr_refs,
> + &cscfg_cfg_attr_nr_presets,
> + &cscfg_cfg_attr_preset_values,
> + NULL,
> +};
> +
> +static struct config_item_type cscfg_config_view_type = {
> + .ct_owner = THIS_MODULE,
> + .ct_attrs = cscfg_config_view_attrs,
> +};
> +
> +static struct config_group *cscfg_create_config_group(struct cscfg_config_desc *cfg_desc)
> +{
> + struct cscfg_fs_config *cfg_view;
> + struct device *dev = cscfg_dev_to_dev();
> +
> + if (!dev)
> + return ERR_PTR(-EINVAL);
> +
> + cfg_view = devm_kzalloc(dev, sizeof(struct cscfg_fs_config), GFP_KERNEL);
> + if (!cfg_view)
> + return ERR_PTR(-ENOMEM);
> +
> + cfg_view->desc = cfg_desc;
> + config_group_init_type_name(&cfg_view->group, cfg_desc->name, &cscfg_config_view_type);
> + return &cfg_view->group;
> +}
> +
> +static struct config_item_type cscfg_configs_type = {
> + .ct_owner = THIS_MODULE,
> +};
> +
> +static struct cscfg_fs_def_group cscfg_configs_grp = {
> + .group = {
> + .cg_item = {
> + .ci_namebuf = "configurations",
> + .ci_type = &cscfg_configs_type,
> + },
> + },
> +};
> +
> +
Extra line
> +/* attributes for features view */
> +
> +static inline struct cscfg_fs_feature *to_cscfg_fs_feature_group(struct config_group *group)
> +{
> + return container_of(group, struct cscfg_fs_feature, group);
> +}
> +
> +static ssize_t cscfg_feat_description_show(struct config_item *item, char *page)
> +{
> + struct cscfg_fs_feature *fs_feat = to_cscfg_fs_feature_group(to_config_group(item));
> +
> + return scnprintf(page, PAGE_SIZE, "%s\n", fs_feat->desc->brief);
> +}
> +CONFIGFS_ATTR_RO(cscfg_feat_, description);
> +
> +static ssize_t cscfg_feat_matches_show(struct config_item *item, char *page)
> +{
> + struct cscfg_fs_feature *fs_feat = to_cscfg_fs_feature_group(to_config_group(item));
> + u32 match_flags = fs_feat->desc->match_flags;
> + int used = 0;
> +
> + if (match_flags & CS_CFG_MATCH_CLASS_SRC_ALL)
> + used = scnprintf(page, PAGE_SIZE, "SRC_ALL ");
> +
> + if (match_flags & CS_CFG_MATCH_CLASS_SRC_ETM4)
> + used += scnprintf(page + used, PAGE_SIZE - used, "SRC_ETMV4 ");
> +
> + if (match_flags & CS_CFG_MATCH_CLASS_CTI_ALL)
> + used += scnprintf(page + used, PAGE_SIZE - used, "CTI_ALL ");
> +
> + if (match_flags & CS_CFG_MATCH_CLASS_CTI_CPU)
> + used += scnprintf(page + used, PAGE_SIZE - used, "CTI_CPU ");
> +
> + if (match_flags & CS_CFG_MATCH_CLASS_CTI_SYS)
> + used += scnprintf(page + used, PAGE_SIZE - used, "CTI_SYS ");
> +
> + used += scnprintf(page + used, PAGE_SIZE - used, "\n");
> + return used;
> +}
> +CONFIGFS_ATTR_RO(cscfg_feat_, matches);
> +
> +static ssize_t cscfg_feat_nr_params_show(struct config_item *item, char *page)
> +{
> + struct cscfg_fs_feature *fs_feat = to_cscfg_fs_feature_group(to_config_group(item));
> +
> + return scnprintf(page, PAGE_SIZE, "%d\n", fs_feat->desc->nr_params);
> +}
> +CONFIGFS_ATTR_RO(cscfg_feat_, nr_params);
> +
> +/* base feature desc attrib structures */
> +static struct configfs_attribute *cscfg_feature_view_attrs[] = {
> + &cscfg_feat_attr_description,
> + &cscfg_feat_attr_matches,
> + &cscfg_feat_attr_nr_params,
> + NULL,
> +};
> +
> +static struct config_item_type cscfg_feature_view_type = {
> + .ct_owner = THIS_MODULE,
> + .ct_attrs = cscfg_feature_view_attrs,
> +};
> +
> +static inline struct cscfg_fs_param *to_cscfg_fs_param_group(struct config_group *group)
> +{
> + return container_of(group, struct cscfg_fs_param, group);
> +}
> +
> +static ssize_t cscfg_param_value_show(struct config_item *item, char *page)
> +{
> + struct cscfg_fs_param *param_item = to_cscfg_fs_param_group(to_config_group(item));
> +
> + return scnprintf(page, PAGE_SIZE, "0x%llx\n", param_item->param->value);
> +}
> +
> +static ssize_t cscfg_param_value_store(struct config_item *item,
> + const char *page, size_t size)
> +{
> + struct cscfg_fs_param *param_item = to_cscfg_fs_param_group(to_config_group(item));
> + u64 val;
> + int err;
> +
> + err = kstrtoull(page, 0, &val);
> + if (err)
> + return err;
> +
> + spin_lock(¶m_item->desc->param_lock);
> + param_item->param->value = val;
> + spin_unlock(¶m_item->desc->param_lock);
> +
> + return size;
> +}
> +CONFIGFS_ATTR(cscfg_param_, value);
> +
> +static struct configfs_attribute *cscfg_param_view_attrs[] = {
> + &cscfg_param_attr_value,
> + NULL,
> +};
> +
> +static struct config_item_type cscfg_param_view_type = {
> + .ct_owner = THIS_MODULE,
> + .ct_attrs = cscfg_param_view_attrs,
> +};
> +
> +static struct config_item_type cscfg_feat_param_group_type = {
> + .ct_owner = THIS_MODULE,
> +};
> +
> +/*
> + * configfs has far less functionality provided to add attributes dynamically than sysfs,
> + * and the show and store fns pass the enclosing config_item so the actual attribute cannot
> + * be determined. Therefore we add each item as a group directory, with a value attribute.
> + */
> +static int cscfg_create_params_group_items(struct cscfg_feature_desc *feat_desc,
> + struct config_group *params_group)
> +{
> + struct device *dev = cscfg_dev_to_dev();
> + struct cscfg_fs_param *param_item;
> + int i;
> +
> + /* parameter items - as groups with default_value attribute */
> + for (i = 0; i < feat_desc->nr_params; i++) {
> + param_item = devm_kzalloc(dev, sizeof(struct cscfg_fs_param), GFP_KERNEL);
> + if (!param_item)
> + return -ENOMEM;
> + param_item->desc = feat_desc;
> + param_item->param = &feat_desc->params[i];
> + config_group_init_type_name(¶m_item->group, param_item->param->name,
> + &cscfg_param_view_type);
> + configfs_add_default_group(¶m_item->group, params_group);
> + }
> + return 0;
> +}
> +
> +static struct config_group *cscfg_create_feature_group(struct cscfg_feature_desc *feat_desc)
> +{
> + struct cscfg_fs_feature *feat_view;
> + struct device *dev = cscfg_dev_to_dev();
> + struct cscfg_fs_def_group *params_group = NULL;
> + int item_err;
> +
> + if (!dev)
> + return ERR_PTR(-EINVAL);
> +
> + feat_view = devm_kzalloc(dev, sizeof(struct cscfg_fs_feature), GFP_KERNEL);
> + if (!feat_view)
> + return ERR_PTR(-ENOMEM);
> +
> + if (feat_desc->nr_params) {
> + params_group = devm_kzalloc(dev, sizeof(struct cscfg_fs_feature), GFP_KERNEL);
> + if (!params_group)
> + return ERR_PTR(-ENOMEM);
> + }
> +
> + feat_view->desc = feat_desc;
> + config_group_init_type_name(&feat_view->group,
> + feat_desc->name,
> + &cscfg_feature_view_type);
> + if (params_group) {
> + config_group_init_type_name(¶ms_group->group, "params",
> + &cscfg_feat_param_group_type);
> + configfs_add_default_group(¶ms_group->group, &feat_view->group);
> + item_err = cscfg_create_params_group_items(feat_desc, ¶ms_group->group);
> + if (item_err)
> + return ERR_PTR(item_err);
> + }
> + return &feat_view->group;
> +}
> +
> +static struct config_item_type cscfg_features_type = {
> + .ct_owner = THIS_MODULE,
> +};
> +
> +static struct cscfg_fs_def_group cscfg_features_grp = {
> + .group = {
> + .cg_item = {
> + .ci_namebuf = "features",
> + .ci_type = &cscfg_features_type,
> + },
> + },
Can we do the following to avoid declaring cscfg_features_type:
static struct cscfg_fs_def_group cscfg_features_grp = {
.group = {
.cg_item = {
.ci_namebuf = "features",
.ci_type = {
.ct_owner = THIS_MODULE,
};
},
},
Same for configuration.
> +};
> +
> +/* add configuration to configurations group */
> +int cscfg_configfs_add_config(struct cscfg_config_desc *cfg_desc)
> +{
> + struct config_group *new_group;
> + int err;
> +
> + new_group = cscfg_create_config_group(cfg_desc);
> + if (IS_ERR(new_group))
> + return PTR_ERR(new_group);
> + err = configfs_register_group(&cscfg_configs_grp.group, new_group);
> + return err;
> +}
> +
> +/* add feature to features group */
> +int cscfg_configfs_add_feature(struct cscfg_feature_desc *feat_desc)
> +{
> + struct config_group *new_group;
> + int err;
> +
> + new_group = cscfg_create_feature_group(feat_desc);
> + if (IS_ERR(new_group))
> + return PTR_ERR(new_group);
> + err = configfs_register_group(&cscfg_features_grp.group, new_group);
> + return err;
> +}
> +
> +static const struct config_item_type syscfg_fs_type = {
> + .ct_owner = THIS_MODULE,
> +};
> +
> +static struct cscfg_fs_subsys syscfg_fs_subsys = {
> + .cfgdev = NULL,
> + .fs_subsys = {
> + .su_group = {
> + .cg_item = {
> + .ci_namebuf = "coresight-syscfg",
> + .ci_type = &syscfg_fs_type,
> + },
> + },
> + },
> +};
> +
> +static inline struct cscfg_device *cscfg_fs_get_cscfg_dev(void)
> +{
> + return syscfg_fs_subsys.cfgdev;
> +}
> +
> +int cscfg_configfs_init(struct cscfg_device *cscfg_dev)
> +{
> + int ret = 0;
> + struct configfs_subsystem *subsys = &syscfg_fs_subsys.fs_subsys;
> +
> + if (!cscfg_dev)
> + return -EINVAL;
> +
> + config_group_init(&subsys->su_group);
> + mutex_init(&subsys->su_mutex);
> +
> + /* Add default groups to subsystem */
> + config_group_init(&cscfg_configs_grp.group);
> + configfs_add_default_group(&cscfg_configs_grp.group, &subsys->su_group);
> +
> + config_group_init(&cscfg_features_grp.group);
> + configfs_add_default_group(&cscfg_features_grp.group, &subsys->su_group);
> +
> + ret = configfs_register_subsystem(subsys);
> + if (!ret) {
> + syscfg_fs_subsys.cfgdev = cscfg_dev;
> + cscfg_dev->cfgfs_subsys = &syscfg_fs_subsys;
> + }
Instead of doing the above I suggest to make cscfg_device::cfgfs_subsys a member
rather than a pointer and call containerof() to get back to the cscfg_device.
That way we avoid the static declaration of cscfg_configs_grp and
cscfg_configs_type above.
Moreover, now that this patchset is sinking in I would rename struct
cscfg_device to cscfg_manager.
> +
> + return ret;
> +}
> +
> +void cscfg_configfs_release(struct cscfg_device *cscfg_dev)
> +{
> + if (cscfg_dev && cscfg_dev->cfgfs_subsys) {
> + configfs_unregister_subsystem(&cscfg_dev->cfgfs_subsys->fs_subsys);
> + cscfg_dev->cfgfs_subsys = NULL;
> + }
> + syscfg_fs_subsys.cfgdev = NULL;
> +}
> diff --git a/drivers/hwtracing/coresight/coresight-syscfg-configfs.h b/drivers/hwtracing/coresight/coresight-syscfg-configfs.h
> new file mode 100644
> index 000000000000..70cc3745649e
> --- /dev/null
> +++ b/drivers/hwtracing/coresight/coresight-syscfg-configfs.h
> @@ -0,0 +1,47 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Coresight system configuration driver - support for configfs.
> + */
> +
> +#ifndef CORESIGHT_SYSCFG_CONFIGFS_H
> +#define CORESIGHT_SYSCFG_CONFIGFS_H
> +
> +#include <linux/configfs.h>
> +#include "coresight-syscfg.h"
> +
> +/* container to associate the device and configfs subsystem */
> +struct cscfg_fs_subsys {
> + struct cscfg_device *cfgdev;
> + struct configfs_subsystem fs_subsys;
> +};
> +
> +/* container for default groups */
> +struct cscfg_fs_def_group {
> + struct config_group group;
> +};
Please don't do that - there is enough new structures in this patchset as it is.
> +
> +/* container for configuration view */
> +struct cscfg_fs_config {
> + struct cscfg_config_desc *desc;
> + struct config_group group;
> +};
> +
> +/* container for feature view */
> +struct cscfg_fs_feature {
> + struct cscfg_feature_desc *desc;
> + struct config_group group;
> +};
> +
> +/* container for parameter view */
> +struct cscfg_fs_param {
> + struct cscfg_parameter_desc *param;
> + struct cscfg_feature_desc *desc;
> + struct config_group group;
> +};
> +
> +int cscfg_configfs_init(struct cscfg_device *dev);
> +void cscfg_configfs_release(struct cscfg_device *dev);
> +int cscfg_configfs_add_config(struct cscfg_config_desc *cfg_desc);
> +int cscfg_configfs_add_feature(struct cscfg_feature_desc *feat_desc);
> +
> +#endif /* CORESIGHT_SYSCFG_CONFIGFS_H */
> diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c
> index 8d52580daf04..2cf67a038cc8 100644
> --- a/drivers/hwtracing/coresight/coresight-syscfg.c
> +++ b/drivers/hwtracing/coresight/coresight-syscfg.c
> @@ -9,6 +9,7 @@
> #include "coresight-config.h"
> #include "coresight-etm-perf.h"
> #include "coresight-syscfg.h"
> +#include "coresight-syscfg-configfs.h"
>
> /*
> * cscfg_ API manages configurations and features for the entire coresight
> @@ -260,6 +261,8 @@ static int cscfg_load_feat(struct cscfg_feature_desc *feat_desc)
> {
> int err;
>
> + spin_lock_init(&feat_desc->param_lock);
> +
> /* add feature to any matching registered devices */
> err = cscfg_add_feat_to_csdevs(feat_desc);
> if (err)
> @@ -294,6 +297,24 @@ static int cscfg_load_config(struct cscfg_config_desc *cfg_desc)
> return err;
> }
>
> +/* get a feature descriptor by name */
> +const struct cscfg_feature_desc *cscfg_get_named_feat_desc(const char *name)
> +{
> + const struct cscfg_feature_desc *feat = NULL, *feat_item;
> +
> + mutex_lock(&cscfg_mutex);
> +
> + list_for_each_entry(feat_item, &cscfg_data.feat_list, item) {
> + if (strcmp(feat_item->name, name) == 0) {
> + feat = feat_item;
> + break;
> + }
> + }
> +
> + mutex_unlock(&cscfg_mutex);
> + return feat;
> +}
> +
> /*
> * External API function to load feature and config sets.
> * Take a 0 terminated array of feature descriptors and/or configuration
> @@ -316,6 +337,7 @@ int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs,
> feat_descs[i]->name);
> goto do_unlock;
> }
> + cscfg_configfs_add_feature(feat_descs[i]);
> i++;
> }
> }
> @@ -330,6 +352,7 @@ int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs,
> cfg_descs[i]->name);
> goto do_unlock;
> }
> + cscfg_configfs_add_config(cfg_descs[i]);
> i++;
> }
> }
> @@ -502,6 +525,7 @@ struct device *to_device_cscfg(void)
> /* Must have a release function or the kernel will complain on module unload */
> void cscfg_dev_release(struct device *dev)
> {
> + cscfg_configfs_release(cscfg_dev);
> kfree(cscfg_dev);
> cscfg_dev = NULL;
> }
> @@ -530,6 +554,7 @@ int cscfg_create_device(void)
> cscfg_dev->cfg_data = &cscfg_data;
>
> err = device_register(dev);
> +
Extra line
> if (err)
> cscfg_dev_release(dev);
>
> @@ -587,6 +612,10 @@ int __init cscfg_init(void)
> if (err)
> goto exit_drv_unregister;
>
> + err = cscfg_configfs_init(cscfg_dev);
> + if (err)
> + goto exit_dev_clear;
> +
> INIT_LIST_HEAD(&cscfg_data.dev_list);
> INIT_LIST_HEAD(&cscfg_data.feat_list);
> INIT_LIST_HEAD(&cscfg_data.config_list);
> @@ -595,6 +624,8 @@ int __init cscfg_init(void)
> dev_info(to_device_cscfg(), "CoreSight Configuration manager initialised");
> return 0;
>
> +exit_dev_clear:
> + cscfg_clear_device();
> exit_drv_unregister:
> cscfg_driver_exit();
> exit_bus_unregister:
> diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h
> index e8f352599dd7..ce237a69677b 100644
> --- a/drivers/hwtracing/coresight/coresight-syscfg.h
> +++ b/drivers/hwtracing/coresight/coresight-syscfg.h
> @@ -6,6 +6,7 @@
> #ifndef CORESIGHT_SYSCFG_H
> #define CORESIGHT_SYSCFG_H
>
> +#include <linux/configfs.h>
Same here, I don't see what this header file is adding.
I'm out of time for today and will continue with the rest of this patch
tomorrow.
Thanks,
Mathieu
> #include <linux/coresight.h>
> #include <linux/device.h>
>
> @@ -46,6 +47,7 @@ struct cscfg_csdev_register {
> int __init cscfg_init(void);
> void __exit cscfg_exit(void);
> int cscfg_preload(void);
> +const struct cscfg_feature_desc *cscfg_get_named_feat_desc(const char *name);
>
> /* syscfg external API */
> int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs,
> @@ -64,10 +66,12 @@ void cscfg_unregister_csdev(struct coresight_device *csdev);
> *
> * @dev: The device.
> * @cfg_data: A reference to the configuration and feature lists
> + * @cfgfs_subsys: configfs subsystem used to manage configurations.
> */
> struct cscfg_device {
> struct device dev;
> struct cscfg_api_data *cfg_data;
> + struct cscfg_fs_subsys *cfgfs_subsys;
> };
>
> /* basic device driver */
> --
> 2.17.1
>
More information about the linux-arm-kernel
mailing list