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|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2021-2022 NVIDIA Corporation
*
* Author: Dipen Patel <dipenp@nvidia.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/mutex.h>
#include <linux/uaccess.h>
#include <linux/hte.h>
#include <linux/delay.h>
#include <linux/debugfs.h>
#include <linux/device.h>
#define HTE_TS_NAME_LEN 10
/* Global list of the HTE devices */
static DEFINE_SPINLOCK(hte_lock);
static LIST_HEAD(hte_devices);
enum {
HTE_TS_REGISTERED,
HTE_TS_REQ,
HTE_TS_DISABLE,
HTE_TS_QUEUE_WK,
};
/**
* struct hte_ts_info - Information related to requested timestamp.
*
* @xlated_id: Timestamp ID as understood between HTE subsys and HTE provider,
* See xlate callback API.
* @flags: Flags holding state information.
* @hte_cb_flags: Callback related flags.
* @seq: Timestamp sequence counter.
* @line_name: HTE allocated line name.
* @free_attr_name: If set, free the attr name.
* @cb: A nonsleeping callback function provided by clients.
* @tcb: A secondary sleeping callback function provided by clients.
* @dropped_ts: Dropped timestamps.
* @slock: Spin lock to synchronize between disable/enable,
* request/release APIs.
* @cb_work: callback workqueue, used when tcb is specified.
* @req_mlock: Lock during timestamp request/release APIs.
* @ts_dbg_root: Root for the debug fs.
* @gdev: HTE abstract device that this timestamp information belongs to.
* @cl_data: Client specific data.
*/
struct hte_ts_info {
u32 xlated_id;
unsigned long flags;
unsigned long hte_cb_flags;
u64 seq;
char *line_name;
bool free_attr_name;
hte_ts_cb_t cb;
hte_ts_sec_cb_t tcb;
atomic_t dropped_ts;
spinlock_t slock;
struct work_struct cb_work;
struct mutex req_mlock;
struct dentry *ts_dbg_root;
struct hte_device *gdev;
void *cl_data;
};
/**
* struct hte_device - HTE abstract device
* @nlines: Number of entities this device supports.
* @ts_req: Total number of entities requested.
* @sdev: Device used at various debug prints.
* @dbg_root: Root directory for debug fs.
* @list: List node to store hte_device for each provider.
* @chip: HTE chip providing this HTE device.
* @owner: helps prevent removal of modules when in use.
* @ei: Timestamp information.
*/
struct hte_device {
u32 nlines;
atomic_t ts_req;
struct device *sdev;
struct dentry *dbg_root;
struct list_head list;
struct hte_chip *chip;
struct module *owner;
struct hte_ts_info ei[] __counted_by(nlines);
};
#ifdef CONFIG_DEBUG_FS
static struct dentry *hte_root;
static int __init hte_subsys_dbgfs_init(void)
{
/* creates /sys/kernel/debug/hte/ */
hte_root = debugfs_create_dir("hte", NULL);
return 0;
}
subsys_initcall(hte_subsys_dbgfs_init);
static void hte_chip_dbgfs_init(struct hte_device *gdev)
{
const struct hte_chip *chip = gdev->chip;
const char *name = chip->name ? chip->name : dev_name(chip->dev);
gdev->dbg_root = debugfs_create_dir(name, hte_root);
debugfs_create_atomic_t("ts_requested", 0444, gdev->dbg_root,
&gdev->ts_req);
debugfs_create_u32("total_ts", 0444, gdev->dbg_root,
&gdev->nlines);
}
static void hte_ts_dbgfs_init(const char *name, struct hte_ts_info *ei)
{
if (!ei->gdev->dbg_root || !name)
return;
ei->ts_dbg_root = debugfs_create_dir(name, ei->gdev->dbg_root);
debugfs_create_atomic_t("dropped_timestamps", 0444, ei->ts_dbg_root,
&ei->dropped_ts);
}
#else
static void hte_chip_dbgfs_init(struct hte_device *gdev)
{
}
static void hte_ts_dbgfs_init(const char *name, struct hte_ts_info *ei)
{
}
#endif
/**
* hte_ts_put() - Release and disable timestamp for the given desc.
*
* @desc: timestamp descriptor.
*
* Context: debugfs_remove_recursive() function call may use sleeping locks,
* not suitable from atomic context.
* Returns: 0 on success or a negative error code on failure.
*/
int hte_ts_put(struct hte_ts_desc *desc)
{
int ret = 0;
unsigned long flag;
struct hte_device *gdev;
struct hte_ts_info *ei;
if (!desc)
return -EINVAL;
ei = desc->hte_data;
if (!ei || !ei->gdev)
return -EINVAL;
gdev = ei->gdev;
mutex_lock(&ei->req_mlock);
if (unlikely(!test_bit(HTE_TS_REQ, &ei->flags) &&
!test_bit(HTE_TS_REGISTERED, &ei->flags))) {
dev_info(gdev->sdev, "id:%d is not requested\n",
desc->attr.line_id);
ret = -EINVAL;
goto unlock;
}
if (unlikely(!test_bit(HTE_TS_REQ, &ei->flags) &&
test_bit(HTE_TS_REGISTERED, &ei->flags))) {
dev_info(gdev->sdev, "id:%d is registered but not requested\n",
desc->attr.line_id);
ret = -EINVAL;
goto unlock;
}
if (test_bit(HTE_TS_REQ, &ei->flags) &&
!test_bit(HTE_TS_REGISTERED, &ei->flags)) {
clear_bit(HTE_TS_REQ, &ei->flags);
desc->hte_data = NULL;
ret = 0;
goto mod_put;
}
ret = gdev->chip->ops->release(gdev->chip, desc, ei->xlated_id);
if (ret) {
dev_err(gdev->sdev, "id: %d free failed\n",
desc->attr.line_id);
goto unlock;
}
kfree(ei->line_name);
if (ei->free_attr_name)
kfree_const(desc->attr.name);
debugfs_remove_recursive(ei->ts_dbg_root);
spin_lock_irqsave(&ei->slock, flag);
if (test_bit(HTE_TS_QUEUE_WK, &ei->flags)) {
spin_unlock_irqrestore(&ei->slock, flag);
flush_work(&ei->cb_work);
spin_lock_irqsave(&ei->slock, flag);
}
atomic_dec(&gdev->ts_req);
atomic_set(&ei->dropped_ts, 0);
ei->seq = 1;
ei->flags = 0;
desc->hte_data = NULL;
spin_unlock_irqrestore(&ei->slock, flag);
ei->cb = NULL;
ei->tcb = NULL;
ei->cl_data = NULL;
mod_put:
module_put(gdev->owner);
unlock:
mutex_unlock(&ei->req_mlock);
dev_dbg(gdev->sdev, "release id: %d\n", desc->attr.line_id);
return ret;
}
EXPORT_SYMBOL_GPL(hte_ts_put);
static int hte_ts_dis_en_common(struct hte_ts_desc *desc, bool en)
{
u32 ts_id;
struct hte_device *gdev;
struct hte_ts_info *ei;
int ret;
unsigned long flag;
if (!desc)
return -EINVAL;
ei = desc->hte_data;
if (!ei || !ei->gdev)
return -EINVAL;
gdev = ei->gdev;
ts_id = desc->attr.line_id;
mutex_lock(&ei->req_mlock);
if (!test_bit(HTE_TS_REGISTERED, &ei->flags)) {
dev_dbg(gdev->sdev, "id:%d is not registered", ts_id);
ret = -EUSERS;
goto out;
}
spin_lock_irqsave(&ei->slock, flag);
if (en) {
if (!test_bit(HTE_TS_DISABLE, &ei->flags)) {
ret = 0;
goto out_unlock;
}
spin_unlock_irqrestore(&ei->slock, flag);
ret = gdev->chip->ops->enable(gdev->chip, ei->xlated_id);
if (ret) {
dev_warn(gdev->sdev, "id: %d enable failed\n",
ts_id);
goto out;
}
spin_lock_irqsave(&ei->slock, flag);
clear_bit(HTE_TS_DISABLE, &ei->flags);
} else {
if (test_bit(HTE_TS_DISABLE, &ei->flags)) {
ret = 0;
goto out_unlock;
}
spin_unlock_irqrestore(&ei->slock, flag);
ret = gdev->chip->ops->disable(gdev->chip, ei->xlated_id);
if (ret) {
dev_warn(gdev->sdev, "id: %d disable failed\n",
ts_id);
goto out;
}
spin_lock_irqsave(&ei->slock, flag);
set_bit(HTE_TS_DISABLE, &ei->flags);
}
out_unlock:
spin_unlock_irqrestore(&ei->slock, flag);
out:
mutex_unlock(&ei->req_mlock);
return ret;
}
/**
* hte_disable_ts() - Disable timestamp on given descriptor.
*
* The API does not release any resources associated with desc.
*
* @desc: ts descriptor, this is the same as returned by the request API.
*
* Context: Holds mutex lock, not suitable from atomic context.
* Returns: 0 on success or a negative error code on failure.
*/
int hte_disable_ts(struct hte_ts_desc *desc)
{
return hte_ts_dis_en_common(desc, false);
}
EXPORT_SYMBOL_GPL(hte_disable_ts);
/**
* hte_enable_ts() - Enable timestamp on given descriptor.
*
* @desc: ts descriptor, this is the same as returned by the request API.
*
* Context: Holds mutex lock, not suitable from atomic context.
* Returns: 0 on success or a negative error code on failure.
*/
int hte_enable_ts(struct hte_ts_desc *desc)
{
return hte_ts_dis_en_common(desc, true);
}
EXPORT_SYMBOL_GPL(hte_enable_ts);
static void hte_do_cb_work(struct work_struct *w)
{
unsigned long flag;
struct hte_ts_info *ei = container_of(w, struct hte_ts_info, cb_work);
if (unlikely(!ei->tcb))
return;
ei->tcb(ei->cl_data);
spin_lock_irqsave(&ei->slock, flag);
clear_bit(HTE_TS_QUEUE_WK, &ei->flags);
spin_unlock_irqrestore(&ei->slock, flag);
}
static int __hte_req_ts(struct hte_ts_desc *desc, hte_ts_cb_t cb,
hte_ts_sec_cb_t tcb, void *data)
{
int ret;
struct hte_device *gdev;
struct hte_ts_info *ei = desc->hte_data;
gdev = ei->gdev;
/*
* There is a chance that multiple consumers requesting same entity,
* lock here.
*/
mutex_lock(&ei->req_mlock);
if (test_bit(HTE_TS_REGISTERED, &ei->flags) ||
!test_bit(HTE_TS_REQ, &ei->flags)) {
dev_dbg(gdev->chip->dev, "id:%u req failed\n",
desc->attr.line_id);
ret = -EUSERS;
goto unlock;
}
ei->cb = cb;
ei->tcb = tcb;
if (tcb)
INIT_WORK(&ei->cb_work, hte_do_cb_work);
ret = gdev->chip->ops->request(gdev->chip, desc, ei->xlated_id);
if (ret < 0) {
dev_err(gdev->chip->dev, "ts request failed\n");
goto unlock;
}
ei->cl_data = data;
ei->seq = 1;
atomic_inc(&gdev->ts_req);
ei->line_name = NULL;
if (!desc->attr.name) {
ei->line_name = kzalloc(HTE_TS_NAME_LEN, GFP_KERNEL);
if (ei->line_name)
scnprintf(ei->line_name, HTE_TS_NAME_LEN, "ts_%u",
desc->attr.line_id);
}
hte_ts_dbgfs_init(desc->attr.name == NULL ?
ei->line_name : desc->attr.name, ei);
set_bit(HTE_TS_REGISTERED, &ei->flags);
dev_dbg(gdev->chip->dev, "id: %u, xlated id:%u",
desc->attr.line_id, ei->xlated_id);
ret = 0;
unlock:
mutex_unlock(&ei->req_mlock);
return ret;
}
static int hte_bind_ts_info_locked(struct hte_ts_info *ei,
struct hte_ts_desc *desc, u32 x_id)
{
int ret = 0;
mutex_lock(&ei->req_mlock);
if (test_bit(HTE_TS_REQ, &ei->flags)) {
dev_dbg(ei->gdev->chip->dev, "id:%u is already requested\n",
desc->attr.line_id);
ret = -EUSERS;
goto out;
}
set_bit(HTE_TS_REQ, &ei->flags);
desc->hte_data = ei;
ei->xlated_id = x_id;
out:
mutex_unlock(&ei->req_mlock);
return ret;
}
static struct hte_device *of_node_to_htedevice(struct device_node *np)
{
struct hte_device *gdev;
spin_lock(&hte_lock);
list_for_each_entry(gdev, &hte_devices, list)
if (gdev->chip && gdev->chip->dev &&
device_match_of_node(gdev->chip->dev, np)) {
spin_unlock(&hte_lock);
return gdev;
}
spin_unlock(&hte_lock);
return ERR_PTR(-ENODEV);
}
static struct hte_device *hte_find_dev_from_linedata(struct hte_ts_desc *desc)
{
struct hte_device *gdev;
spin_lock(&hte_lock);
list_for_each_entry(gdev, &hte_devices, list)
if (gdev->chip && gdev->chip->match_from_linedata) {
if (!gdev->chip->match_from_linedata(gdev->chip, desc))
continue;
spin_unlock(&hte_lock);
return gdev;
}
spin_unlock(&hte_lock);
return ERR_PTR(-ENODEV);
}
/**
* of_hte_req_count - Return the number of entities to timestamp.
*
* The function returns the total count of the requested entities to timestamp
* by parsing device tree.
*
* @dev: The HTE consumer.
*
* Returns: Positive number on success, -ENOENT if no entries,
* -EINVAL for other errors.
*/
int of_hte_req_count(struct device *dev)
{
int count;
if (!dev || !dev->of_node)
return -EINVAL;
count = of_count_phandle_with_args(dev->of_node, "timestamps",
"#timestamp-cells");
return count ? count : -ENOENT;
}
EXPORT_SYMBOL_GPL(of_hte_req_count);
static inline struct hte_device *hte_get_dev(struct hte_ts_desc *desc)
{
return hte_find_dev_from_linedata(desc);
}
static struct hte_device *hte_of_get_dev(struct device *dev,
struct hte_ts_desc *desc,
int index,
struct of_phandle_args *args,
bool *free_name)
{
int ret;
struct device_node *np;
char *temp;
if (!dev->of_node)
return ERR_PTR(-EINVAL);
np = dev->of_node;
if (!of_property_present(np, "timestamp-names")) {
/* Let hte core construct it during request time */
desc->attr.name = NULL;
} else {
ret = of_property_read_string_index(np, "timestamp-names",
index, &desc->attr.name);
if (ret) {
pr_err("can't parse \"timestamp-names\" property\n");
return ERR_PTR(ret);
}
*free_name = false;
if (desc->attr.name) {
temp = skip_spaces(desc->attr.name);
if (!*temp)
desc->attr.name = NULL;
}
}
ret = of_parse_phandle_with_args(np, "timestamps", "#timestamp-cells",
index, args);
if (ret) {
pr_err("%s(): can't parse \"timestamps\" property\n",
__func__);
return ERR_PTR(ret);
}
of_node_put(args->np);
return of_node_to_htedevice(args->np);
}
/**
* hte_ts_get() - The function to initialize and obtain HTE desc.
*
* The function initializes the consumer provided HTE descriptor. If consumer
* has device tree node, index is used to parse the line id and other details.
* The function needs to be called before using any request APIs.
*
* @dev: HTE consumer/client device, used in case of parsing device tree node.
* @desc: Pre-allocated timestamp descriptor.
* @index: The index will be used as an index to parse line_id from the
* device tree node if node is present.
*
* Context: Holds mutex lock.
* Returns: Returns 0 on success or negative error code on failure.
*/
int hte_ts_get(struct device *dev, struct hte_ts_desc *desc, int index)
{
struct hte_device *gdev;
struct hte_ts_info *ei;
const struct fwnode_handle *fwnode;
struct of_phandle_args args;
u32 xlated_id;
int ret;
bool free_name = false;
if (!desc)
return -EINVAL;
fwnode = dev ? dev_fwnode(dev) : NULL;
if (is_of_node(fwnode))
gdev = hte_of_get_dev(dev, desc, index, &args, &free_name);
else
gdev = hte_get_dev(desc);
if (IS_ERR(gdev)) {
pr_err("%s() no hte dev found\n", __func__);
return PTR_ERR(gdev);
}
if (!try_module_get(gdev->owner))
return -ENODEV;
if (!gdev->chip) {
pr_err("%s(): requested id does not have provider\n",
__func__);
ret = -ENODEV;
goto put;
}
if (is_of_node(fwnode)) {
if (!gdev->chip->xlate_of)
ret = -EINVAL;
else
ret = gdev->chip->xlate_of(gdev->chip, &args,
desc, &xlated_id);
} else {
if (!gdev->chip->xlate_plat)
ret = -EINVAL;
else
ret = gdev->chip->xlate_plat(gdev->chip, desc,
&xlated_id);
}
if (ret < 0)
goto put;
ei = &gdev->ei[xlated_id];
ret = hte_bind_ts_info_locked(ei, desc, xlated_id);
if (ret)
goto put;
ei->free_attr_name = free_name;
return 0;
put:
module_put(gdev->owner);
return ret;
}
EXPORT_SYMBOL_GPL(hte_ts_get);
static void __devm_hte_release_ts(void *res)
{
hte_ts_put(res);
}
/**
* hte_request_ts_ns() - The API to request and enable hardware timestamp in
* nanoseconds.
*
* The entity is provider specific for example, GPIO lines, signals, buses
* etc...The API allocates necessary resources and enables the timestamp.
*
* @desc: Pre-allocated and initialized timestamp descriptor.
* @cb: Callback to push the timestamp data to consumer.
* @tcb: Optional callback. If its provided, subsystem initializes
* workqueue. It is called when cb returns HTE_RUN_SECOND_CB.
* @data: Client data, used during cb and tcb callbacks.
*
* Context: Holds mutex lock.
* Returns: Returns 0 on success or negative error code on failure.
*/
int hte_request_ts_ns(struct hte_ts_desc *desc, hte_ts_cb_t cb,
hte_ts_sec_cb_t tcb, void *data)
{
int ret;
struct hte_ts_info *ei;
if (!desc || !desc->hte_data || !cb)
return -EINVAL;
ei = desc->hte_data;
if (!ei || !ei->gdev)
return -EINVAL;
ret = __hte_req_ts(desc, cb, tcb, data);
if (ret < 0) {
dev_err(ei->gdev->chip->dev,
"failed to request id: %d\n", desc->attr.line_id);
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(hte_request_ts_ns);
/**
* devm_hte_request_ts_ns() - Resource managed API to request and enable
* hardware timestamp in nanoseconds.
*
* The entity is provider specific for example, GPIO lines, signals, buses
* etc...The API allocates necessary resources and enables the timestamp. It
* deallocates and disables automatically when the consumer exits.
*
* @dev: HTE consumer/client device.
* @desc: Pre-allocated and initialized timestamp descriptor.
* @cb: Callback to push the timestamp data to consumer.
* @tcb: Optional callback. If its provided, subsystem initializes
* workqueue. It is called when cb returns HTE_RUN_SECOND_CB.
* @data: Client data, used during cb and tcb callbacks.
*
* Context: Holds mutex lock.
* Returns: Returns 0 on success or negative error code on failure.
*/
int devm_hte_request_ts_ns(struct device *dev, struct hte_ts_desc *desc,
hte_ts_cb_t cb, hte_ts_sec_cb_t tcb,
void *data)
{
int err;
if (!dev)
return -EINVAL;
err = hte_request_ts_ns(desc, cb, tcb, data);
if (err)
return err;
err = devm_add_action_or_reset(dev, __devm_hte_release_ts, desc);
if (err)
return err;
return 0;
}
EXPORT_SYMBOL_GPL(devm_hte_request_ts_ns);
/**
* hte_init_line_attr() - Initialize line attributes.
*
* Zeroes out line attributes and initializes with provided arguments.
* The function needs to be called before calling any consumer facing
* functions.
*
* @desc: Pre-allocated timestamp descriptor.
* @line_id: line id.
* @edge_flags: edge flags related to line_id.
* @name: name of the line.
* @data: line data related to line_id.
*
* Context: Any.
* Returns: 0 on success or negative error code for the failure.
*/
int hte_init_line_attr(struct hte_ts_desc *desc, u32 line_id,
unsigned long edge_flags, const char *name, void *data)
{
if (!desc)
return -EINVAL;
memset(&desc->attr, 0, sizeof(desc->attr));
desc->attr.edge_flags = edge_flags;
desc->attr.line_id = line_id;
desc->attr.line_data = data;
if (name) {
name = kstrdup_const(name, GFP_KERNEL);
if (!name)
return -ENOMEM;
}
desc->attr.name = name;
return 0;
}
EXPORT_SYMBOL_GPL(hte_init_line_attr);
/**
* hte_get_clk_src_info() - Get the clock source information for a ts
* descriptor.
*
* @desc: ts descriptor, same as returned from request API.
* @ci: The API fills this structure with the clock information data.
*
* Context: Any context.
* Returns: 0 on success else negative error code on failure.
*/
int hte_get_clk_src_info(const struct hte_ts_desc *desc,
struct hte_clk_info *ci)
{
struct hte_chip *chip;
struct hte_ts_info *ei;
if (!desc || !desc->hte_data || !ci) {
pr_debug("%s:%d\n", __func__, __LINE__);
return -EINVAL;
}
ei = desc->hte_data;
if (!ei->gdev || !ei->gdev->chip)
return -EINVAL;
chip = ei->gdev->chip;
if (!chip->ops->get_clk_src_info)
return -EOPNOTSUPP;
return chip->ops->get_clk_src_info(chip, ci);
}
EXPORT_SYMBOL_GPL(hte_get_clk_src_info);
/**
* hte_push_ts_ns() - Push timestamp data in nanoseconds.
*
* It is used by the provider to push timestamp data.
*
* @chip: The HTE chip, used during the registration.
* @xlated_id: entity id understood by both subsystem and provider, this is
* obtained from xlate callback during request API.
* @data: timestamp data.
*
* Returns: 0 on success or a negative error code on failure.
*/
int hte_push_ts_ns(const struct hte_chip *chip, u32 xlated_id,
struct hte_ts_data *data)
{
enum hte_return ret;
int st = 0;
struct hte_ts_info *ei;
unsigned long flag;
if (!chip || !data || !chip->gdev)
return -EINVAL;
if (xlated_id >= chip->nlines)
return -EINVAL;
ei = &chip->gdev->ei[xlated_id];
spin_lock_irqsave(&ei->slock, flag);
/* timestamp sequence counter */
data->seq = ei->seq++;
if (!test_bit(HTE_TS_REGISTERED, &ei->flags) ||
test_bit(HTE_TS_DISABLE, &ei->flags)) {
dev_dbg(chip->dev, "Unknown timestamp push\n");
atomic_inc(&ei->dropped_ts);
st = -EINVAL;
goto unlock;
}
ret = ei->cb(data, ei->cl_data);
if (ret == HTE_RUN_SECOND_CB && ei->tcb) {
queue_work(system_unbound_wq, &ei->cb_work);
set_bit(HTE_TS_QUEUE_WK, &ei->flags);
}
unlock:
spin_unlock_irqrestore(&ei->slock, flag);
return st;
}
EXPORT_SYMBOL_GPL(hte_push_ts_ns);
static int hte_register_chip(struct hte_chip *chip)
{
struct hte_device *gdev;
u32 i;
if (!chip || !chip->dev || !chip->dev->of_node)
return -EINVAL;
if (!chip->ops || !chip->ops->request || !chip->ops->release) {
dev_err(chip->dev, "Driver needs to provide ops\n");
return -EINVAL;
}
gdev = kzalloc(struct_size(gdev, ei, chip->nlines), GFP_KERNEL);
if (!gdev)
return -ENOMEM;
gdev->chip = chip;
chip->gdev = gdev;
gdev->nlines = chip->nlines;
gdev->sdev = chip->dev;
for (i = 0; i < chip->nlines; i++) {
gdev->ei[i].gdev = gdev;
mutex_init(&gdev->ei[i].req_mlock);
spin_lock_init(&gdev->ei[i].slock);
}
if (chip->dev->driver)
gdev->owner = chip->dev->driver->owner;
else
gdev->owner = THIS_MODULE;
of_node_get(chip->dev->of_node);
INIT_LIST_HEAD(&gdev->list);
spin_lock(&hte_lock);
list_add_tail(&gdev->list, &hte_devices);
spin_unlock(&hte_lock);
hte_chip_dbgfs_init(gdev);
dev_dbg(chip->dev, "Added hte chip\n");
return 0;
}
static int hte_unregister_chip(struct hte_chip *chip)
{
struct hte_device *gdev;
if (!chip)
return -EINVAL;
gdev = chip->gdev;
spin_lock(&hte_lock);
list_del(&gdev->list);
spin_unlock(&hte_lock);
gdev->chip = NULL;
of_node_put(chip->dev->of_node);
debugfs_remove_recursive(gdev->dbg_root);
kfree(gdev);
dev_dbg(chip->dev, "Removed hte chip\n");
return 0;
}
static void _hte_devm_unregister_chip(void *chip)
{
hte_unregister_chip(chip);
}
/**
* devm_hte_register_chip() - Resource managed API to register HTE chip.
*
* It is used by the provider to register itself with the HTE subsystem.
* The unregistration is done automatically when the provider exits.
*
* @chip: the HTE chip to add to subsystem.
*
* Returns: 0 on success or a negative error code on failure.
*/
int devm_hte_register_chip(struct hte_chip *chip)
{
int err;
err = hte_register_chip(chip);
if (err)
return err;
err = devm_add_action_or_reset(chip->dev, _hte_devm_unregister_chip,
chip);
if (err)
return err;
return 0;
}
EXPORT_SYMBOL_GPL(devm_hte_register_chip);
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