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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/hte/hte.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/hte/hte.c')
-rw-r--r--drivers/hte/hte.c947
1 files changed, 947 insertions, 0 deletions
diff --git a/drivers/hte/hte.c b/drivers/hte/hte.c
new file mode 100644
index 0000000000..598a716b73
--- /dev/null
+++ b/drivers/hte/hte.c
@@ -0,0 +1,947 @@
+// 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[];
+};
+
+#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);