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net: wan: Add framer framework support

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A framer is a component in charge of an E1/T1 line interface.
Connected usually to a TDM bus, it converts TDM frames to/from E1/T1
frames. It also provides information related to the E1/T1 line.

The framer framework provides a set of APIs for the framer drivers
(framer provider) to create/destroy a framer and APIs for the framer
users (framer consumer) to obtain a reference to the framer, and
use the framer.

This basic implementation provides a framer abstraction for:
 - power on/off the framer
 - get the framer status (line state)
 - be notified on framer status changes
 - get/set the framer configuration

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20231128132534.258459-2-herve.codina@bootlin.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Herve Codina 2023-11-28 14:25:30 +01:00 committed by Linus Walleij
parent b85ea95d08
commit 82c944d05b
7 changed files with 1316 additions and 0 deletions
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2
drivers/net/wan/Kconfig
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@ -95,6 +95,8 @@ config HDLC_X25
comment "X.25/LAPB support is disabled"
depends on HDLC && (LAPB!=m || HDLC!=m) && LAPB!=y
source "drivers/net/wan/framer/Kconfig"
config PCI200SYN
tristate "Goramo PCI200SYN support"
depends on HDLC && PCI

2
drivers/net/wan/Makefile
View File

@ -14,6 +14,8 @@ obj-$(CONFIG_HDLC_FR) += hdlc_fr.o
obj-$(CONFIG_HDLC_PPP) += hdlc_ppp.o
obj-$(CONFIG_HDLC_X25) += hdlc_x25.o
obj-y += framer/
obj-$(CONFIG_FARSYNC) += farsync.o
obj-$(CONFIG_LAPBETHER) += lapbether.o

25
drivers/net/wan/framer/Kconfig Normal file
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@ -0,0 +1,25 @@
# SPDX-License-Identifier: GPL-2.0-only
#
# FRAMER
#
menuconfig FRAMER
tristate "Framer Subsystem"
help
A framer is a component in charge of an E1/T1 line interface.
Connected usually to a TDM bus, it converts TDM frames to/from E1/T1
frames. It also provides information related to the E1/T1 line.
Used with HDLC, the network can be reached through the E1/T1 line.
This framework is designed to provide a generic interface for framer
devices present in the kernel. This layer will have the generic
API by which framer drivers can create framer using the framer
framework and framer users can obtain reference to the framer.
All the users of this framework should select this config.
if FRAMER
config GENERIC_FRAMER
bool
endif # FRAMER

6
drivers/net/wan/framer/Makefile Normal file
View File

@ -0,0 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
#
# Makefile for the framer drivers.
#
obj-$(CONFIG_GENERIC_FRAMER) += framer-core.o

882
drivers/net/wan/framer/framer-core.c Normal file
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@ -0,0 +1,882 @@
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Generic Framer framework.
*
* Copyright 2023 CS GROUP France
*
* Author: Herve Codina <herve.codina@bootlin.com>
*/
#include <linux/device.h>
#include <linux/framer/framer.h>
#include <linux/framer/framer-provider.h>
#include <linux/idr.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/of.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
static struct class *framer_class;
static DEFINE_MUTEX(framer_provider_mutex);
static LIST_HEAD(framer_provider_list);
static DEFINE_IDA(framer_ida);
#define dev_to_framer(a) (container_of((a), struct framer, dev))
int framer_pm_runtime_get(struct framer *framer)
{
int ret;
if (!pm_runtime_enabled(&framer->dev))
return -EOPNOTSUPP;
ret = pm_runtime_get(&framer->dev);
if (ret < 0 && ret != -EINPROGRESS)
pm_runtime_put_noidle(&framer->dev);
return ret;
}
EXPORT_SYMBOL_GPL(framer_pm_runtime_get);
int framer_pm_runtime_get_sync(struct framer *framer)
{
int ret;
if (!pm_runtime_enabled(&framer->dev))
return -EOPNOTSUPP;
ret = pm_runtime_get_sync(&framer->dev);
if (ret < 0)
pm_runtime_put_sync(&framer->dev);
return ret;
}
EXPORT_SYMBOL_GPL(framer_pm_runtime_get_sync);
int framer_pm_runtime_put(struct framer *framer)
{
if (!pm_runtime_enabled(&framer->dev))
return -EOPNOTSUPP;
return pm_runtime_put(&framer->dev);
}
EXPORT_SYMBOL_GPL(framer_pm_runtime_put);
int framer_pm_runtime_put_sync(struct framer *framer)
{
if (!pm_runtime_enabled(&framer->dev))
return -EOPNOTSUPP;
return pm_runtime_put_sync(&framer->dev);
}
EXPORT_SYMBOL_GPL(framer_pm_runtime_put_sync);
/**
* framer_init - framer internal initialization before framer operation
* @framer: the framer returned by framer_get()
*
* Used to allow framer's driver to perform framer internal initialization,
* such as PLL block powering, clock initialization or anything that's
* is required by the framer to perform the start of operation.
* Must be called before framer_power_on().
*
* Return: %0 if successful, a negative error code otherwise
*/
int framer_init(struct framer *framer)
{
bool start_polling = false;
int ret;
ret = framer_pm_runtime_get_sync(framer);
if (ret < 0 && ret != -EOPNOTSUPP)
return ret;
ret = 0; /* Override possible ret == -EOPNOTSUPP */
mutex_lock(&framer->mutex);
if (framer->power_count > framer->init_count)
dev_warn(&framer->dev, "framer_power_on was called before framer init\n");
if (framer->init_count == 0) {
if (framer->ops->init) {
ret = framer->ops->init(framer);
if (ret < 0) {
dev_err(&framer->dev, "framer init failed --> %d\n", ret);
goto out;
}
}
if (framer->ops->flags & FRAMER_FLAG_POLL_STATUS)
start_polling = true;
}
++framer->init_count;
out:
mutex_unlock(&framer->mutex);
if (!ret && start_polling) {
ret = framer_get_status(framer, &framer->prev_status);
if (ret < 0) {
dev_warn(&framer->dev, "framer get status failed --> %d\n", ret);
/* Will be retried on polling_work */
ret = 0;
}
queue_delayed_work(system_power_efficient_wq, &framer->polling_work, 1 * HZ);
}
framer_pm_runtime_put(framer);
return ret;
}
EXPORT_SYMBOL_GPL(framer_init);
/**
* framer_exit - Framer internal un-initialization
* @framer: the framer returned by framer_get()
*
* Must be called after framer_power_off().
*/
int framer_exit(struct framer *framer)
{
int ret;
ret = framer_pm_runtime_get_sync(framer);
if (ret < 0 && ret != -EOPNOTSUPP)
return ret;
ret = 0; /* Override possible ret == -EOPNOTSUPP */
mutex_lock(&framer->mutex);
--framer->init_count;
if (framer->init_count == 0) {
if (framer->ops->flags & FRAMER_FLAG_POLL_STATUS) {
mutex_unlock(&framer->mutex);
cancel_delayed_work_sync(&framer->polling_work);
mutex_lock(&framer->mutex);
}
if (framer->ops->exit)
framer->ops->exit(framer);
}
mutex_unlock(&framer->mutex);
framer_pm_runtime_put(framer);
return ret;
}
EXPORT_SYMBOL_GPL(framer_exit);
/**
* framer_power_on - Enable the framer and enter proper operation
* @framer: the framer returned by framer_get()
*
* Must be called after framer_init().
*
* Return: %0 if successful, a negative error code otherwise
*/
int framer_power_on(struct framer *framer)
{
int ret;
if (framer->pwr) {
ret = regulator_enable(framer->pwr);
if (ret)
return ret;
}
ret = framer_pm_runtime_get_sync(framer);
if (ret < 0 && ret != -EOPNOTSUPP)
goto err_pm_sync;
mutex_lock(&framer->mutex);
if (framer->power_count == 0 && framer->ops->power_on) {
ret = framer->ops->power_on(framer);
if (ret < 0) {
dev_err(&framer->dev, "framer poweron failed --> %d\n", ret);
goto err_pwr_on;
}
}
++framer->power_count;
mutex_unlock(&framer->mutex);
return 0;
err_pwr_on:
mutex_unlock(&framer->mutex);
framer_pm_runtime_put_sync(framer);
err_pm_sync:
if (framer->pwr)
regulator_disable(framer->pwr);
return ret;
}
EXPORT_SYMBOL_GPL(framer_power_on);
/**
* framer_power_off - Disable the framer.
* @framer: the framer returned by framer_get()
*
* Must be called before framer_exit().
*
* Return: %0 if successful, a negative error code otherwise
*/
int framer_power_off(struct framer *framer)
{
int ret;
mutex_lock(&framer->mutex);
if (framer->power_count == 1 && framer->ops->power_off) {
ret = framer->ops->power_off(framer);
if (ret < 0) {
dev_err(&framer->dev, "framer poweroff failed --> %d\n", ret);
mutex_unlock(&framer->mutex);
return ret;
}
}
--framer->power_count;
mutex_unlock(&framer->mutex);
framer_pm_runtime_put(framer);
if (framer->pwr)
regulator_disable(framer->pwr);
return 0;
}
EXPORT_SYMBOL_GPL(framer_power_off);
/**
* framer_get_status() - Gets the framer status
* @framer: the framer returned by framer_get()
* @status: the status to retrieve
*
* Used to get the framer status. framer_init() must have been called
* on the framer.
*
* Return: %0 if successful, a negative error code otherwise
*/
int framer_get_status(struct framer *framer, struct framer_status *status)
{
int ret;
if (!framer->ops->get_status)
return -EOPNOTSUPP;
/* Be sure to have known values (struct padding and future extensions) */
memset(status, 0, sizeof(*status));
mutex_lock(&framer->mutex);
ret = framer->ops->get_status(framer, status);
mutex_unlock(&framer->mutex);
return ret;
}
EXPORT_SYMBOL_GPL(framer_get_status);
/**
* framer_set_config() - Sets the framer configuration
* @framer: the framer returned by framer_get()
* @config: the configuration to set
*
* Used to set the framer configuration. framer_init() must have been called
* on the framer.
*
* Return: %0 if successful, a negative error code otherwise
*/
int framer_set_config(struct framer *framer, const struct framer_config *config)
{
int ret;
if (!framer->ops->set_config)
return -EOPNOTSUPP;
mutex_lock(&framer->mutex);
ret = framer->ops->set_config(framer, config);
mutex_unlock(&framer->mutex);
return ret;
}
EXPORT_SYMBOL_GPL(framer_set_config);
/**
* framer_get_config() - Gets the framer configuration
* @framer: the framer returned by framer_get()
* @config: the configuration to retrieve
*
* Used to get the framer configuration. framer_init() must have been called
* on the framer.
*
* Return: %0 if successful, a negative error code otherwise
*/
int framer_get_config(struct framer *framer, struct framer_config *config)
{
int ret;
if (!framer->ops->get_config)
return -EOPNOTSUPP;
mutex_lock(&framer->mutex);
ret = framer->ops->get_config(framer, config);
mutex_unlock(&framer->mutex);
return ret;
}
EXPORT_SYMBOL_GPL(framer_get_config);
static void framer_polling_work(struct work_struct *work)
{
struct framer *framer = container_of(work, struct framer, polling_work.work);
struct framer_status status;
int ret;
ret = framer_get_status(framer, &status);
if (ret) {
dev_err(&framer->dev, "polling, get status failed (%d)\n", ret);
goto end;
}
if (memcmp(&framer->prev_status, &status, sizeof(status))) {
blocking_notifier_call_chain(&framer->notifier_list,
FRAMER_EVENT_STATUS, NULL);
memcpy(&framer->prev_status, &status, sizeof(status));
}
end:
/* Re-schedule task in 1 sec */
queue_delayed_work(system_power_efficient_wq, &framer->polling_work, 1 * HZ);
}
/**
* framer_notifier_register() - Registers a notifier
* @framer: the framer returned by framer_get()
* @nb: the notifier block to register
*
* Used to register a notifier block on framer events. framer_init() must have
* been called on the framer.
* The available framer events are present in enum framer_events.
*
* Return: %0 if successful, a negative error code otherwise
*/
int framer_notifier_register(struct framer *framer, struct notifier_block *nb)
{
return blocking_notifier_chain_register(&framer->notifier_list, nb);
}
EXPORT_SYMBOL_GPL(framer_notifier_register);
/**
* framer_notifier_unregister() - Unregisters a notifier
* @framer: the framer returned by framer_get()
* @nb: the notifier block to unregister
*
* Used to unregister a notifier block. framer_init() must have
* been called on the framer.
*
* Return: %0 if successful, a negative error code otherwise
*/
int framer_notifier_unregister(struct framer *framer, struct notifier_block *nb)
{
return blocking_notifier_chain_unregister(&framer->notifier_list, nb);
}
EXPORT_SYMBOL_GPL(framer_notifier_unregister);
static struct framer_provider *framer_provider_of_lookup(const struct device_node *node)
{
struct framer_provider *framer_provider;
list_for_each_entry(framer_provider, &framer_provider_list, list) {
if (device_match_of_node(framer_provider->dev, node))
return framer_provider;
}
return ERR_PTR(-EPROBE_DEFER);
}
static struct framer *framer_of_get_from_provider(struct of_phandle_args *args)
{
struct framer_provider *framer_provider;
struct framer *framer;
mutex_lock(&framer_provider_mutex);
framer_provider = framer_provider_of_lookup(args->np);
if (IS_ERR(framer_provider) || !try_module_get(framer_provider->owner)) {
framer = ERR_PTR(-EPROBE_DEFER);
goto end;
}
framer = framer_provider->of_xlate(framer_provider->dev, args);
module_put(framer_provider->owner);
end:
mutex_unlock(&framer_provider_mutex);
return framer;
}
static struct framer *framer_of_get_byphandle(struct device_node *np, const char *propname,
int index)
{
struct of_phandle_args args;
struct framer *framer;
int ret;
ret = of_parse_phandle_with_optional_args(np, propname, "#framer-cells", index, &args);
if (ret)
return ERR_PTR(-ENODEV);
if (!of_device_is_available(args.np)) {
framer = ERR_PTR(-ENODEV);
goto out_node_put;
}
framer = framer_of_get_from_provider(&args);
out_node_put:
of_node_put(args.np);
return framer;
}
static struct framer *framer_of_get_byparent(struct device_node *np, int index)
{
struct of_phandle_args args;
struct framer *framer;
args.np = of_get_parent(np);
args.args_count = 1;
args.args[0] = index;
while (args.np) {
framer = framer_of_get_from_provider(&args);
if (IS_ERR(framer) && PTR_ERR(framer) != -EPROBE_DEFER) {
args.np = of_get_next_parent(args.np);
continue;
}
of_node_put(args.np);
return framer;
}
return ERR_PTR(-ENODEV);
}
/**
* framer_get() - lookup and obtain a reference to a framer.
* @dev: device that requests the framer
* @con_id: name of the framer from device's point of view
*
* Returns the framer driver, after getting a refcount to it; or
* -ENODEV if there is no such framer. The caller is responsible for
* calling framer_put() to release that count.
*/
struct framer *framer_get(struct device *dev, const char *con_id)
{
struct framer *framer = ERR_PTR(-ENODEV);
struct device_link *link;
int ret;
if (dev->of_node) {
if (con_id)
framer = framer_of_get_byphandle(dev->of_node, con_id, 0);
else
framer = framer_of_get_byparent(dev->of_node, 0);
}
if (IS_ERR(framer))
return framer;
get_device(&framer->dev);
if (!try_module_get(framer->ops->owner)) {
ret = -EPROBE_DEFER;
goto err_put_device;
}
link = device_link_add(dev, &framer->dev, DL_FLAG_STATELESS);
if (!link) {
dev_err(dev, "failed to create device_link to %s\n", dev_name(&framer->dev));
ret = -EPROBE_DEFER;
goto err_module_put;
}
return framer;
err_module_put:
module_put(framer->ops->owner);
err_put_device:
put_device(&framer->dev);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(framer_get);
/**
* framer_put() - release the framer
* @dev: device that wants to release this framer
* @framer: the framer returned by framer_get()
*
* Releases a refcount the caller received from framer_get().
*/
void framer_put(struct device *dev, struct framer *framer)
{
device_link_remove(dev, &framer->dev);
module_put(framer->ops->owner);
put_device(&framer->dev);
}
EXPORT_SYMBOL_GPL(framer_put);
static void devm_framer_put(struct device *dev, void *res)
{
struct framer *framer = *(struct framer **)res;
framer_put(dev, framer);
}
/**
* devm_framer_get() - lookup and obtain a reference to a framer.
* @dev: device that requests this framer
* @con_id: name of the framer from device's point of view
*
* Gets the framer using framer_get(), and associates a device with it using
* devres. On driver detach, framer_put() function is invoked on the devres
* data, then, devres data is freed.
*/
struct framer *devm_framer_get(struct device *dev, const char *con_id)
{
struct framer **ptr, *framer;
ptr = devres_alloc(devm_framer_put, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
framer = framer_get(dev, con_id);
if (!IS_ERR(framer)) {
*ptr = framer;
devres_add(dev, ptr);
} else {
devres_free(ptr);
return framer;
}
return framer;
}
EXPORT_SYMBOL_GPL(devm_framer_get);
/**
* devm_framer_optional_get() - lookup and obtain a reference to an optional
* framer.
* @dev: device that requests this framer
* @con_id: name of the framer from device's point of view
*
* Same as devm_framer_get() except that if the framer does not exist, it is not
* considered an error and -ENODEV will not be returned. Instead the NULL framer
* is returned.
*/
struct framer *devm_framer_optional_get(struct device *dev, const char *con_id)
{
struct framer *framer = devm_framer_get(dev, con_id);
if (PTR_ERR(framer) == -ENODEV)
framer = NULL;
return framer;
}
EXPORT_SYMBOL_GPL(devm_framer_optional_get);
static void framer_notify_status_work(struct work_struct *work)
{
struct framer *framer = container_of(work, struct framer, notify_status_work);
blocking_notifier_call_chain(&framer->notifier_list, FRAMER_EVENT_STATUS, NULL);
}
void framer_notify_status_change(struct framer *framer)
{
/* Can be called from atomic context -> just schedule a task to call
* blocking notifiers
*/
queue_work(system_power_efficient_wq, &framer->notify_status_work);
}
EXPORT_SYMBOL_GPL(framer_notify_status_change);
/**
* framer_create() - create a new framer
* @dev: device that is creating the new framer
* @node: device node of the framer. default to dev->of_node.
* @ops: function pointers for performing framer operations
*
* Called to create a framer using framer framework.
*/
struct framer *framer_create(struct device *dev, struct device_node *node,
const struct framer_ops *ops)
{
struct framer *framer;
int ret;
int id;
/* get_status() is mandatory if the provider ask for polling status */
if (WARN_ON((ops->flags & FRAMER_FLAG_POLL_STATUS) && !ops->get_status))
return ERR_PTR(-EINVAL);
framer = kzalloc(sizeof(*framer), GFP_KERNEL);
if (!framer)
return ERR_PTR(-ENOMEM);
id = ida_alloc(&framer_ida, GFP_KERNEL);
if (id < 0) {
dev_err(dev, "unable to get id\n");
ret = id;
goto free_framer;
}
device_initialize(&framer->dev);
mutex_init(&framer->mutex);
INIT_WORK(&framer->notify_status_work, framer_notify_status_work);
INIT_DELAYED_WORK(&framer->polling_work, framer_polling_work);
BLOCKING_INIT_NOTIFIER_HEAD(&framer->notifier_list);
framer->dev.class = framer_class;
framer->dev.parent = dev;
framer->dev.of_node = node ? node : dev->of_node;
framer->id = id;
framer->ops = ops;
ret = dev_set_name(&framer->dev, "framer-%s.%d", dev_name(dev), id);
if (ret)
goto put_dev;
/* framer-supply */
framer->pwr = regulator_get_optional(&framer->dev, "framer");
if (IS_ERR(framer->pwr)) {
ret = PTR_ERR(framer->pwr);
if (ret == -EPROBE_DEFER)
goto put_dev;
framer->pwr = NULL;
}
ret = device_add(&framer->dev);
if (ret)
goto put_dev;
if (pm_runtime_enabled(dev)) {
pm_runtime_enable(&framer->dev);
pm_runtime_no_callbacks(&framer->dev);
}
return framer;
put_dev:
put_device(&framer->dev); /* calls framer_release() which frees resources */
return ERR_PTR(ret);
free_framer:
kfree(framer);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(framer_create);
/**
* framer_destroy() - destroy the framer
* @framer: the framer to be destroyed
*
* Called to destroy the framer.
*/
void framer_destroy(struct framer *framer)
{
/* polling_work should already be stopped but if framer_exit() was not
* called (bug), here it's the last time to do that ...
*/
cancel_delayed_work_sync(&framer->polling_work);
cancel_work_sync(&framer->notify_status_work);
pm_runtime_disable(&framer->dev);
device_unregister(&framer->dev); /* calls framer_release() which frees resources */
}
EXPORT_SYMBOL_GPL(framer_destroy);
static void devm_framer_destroy(struct device *dev, void *res)
{
struct framer *framer = *(struct framer **)res;
framer_destroy(framer);
}
/**
* devm_framer_create() - create a new framer
* @dev: device that is creating the new framer
* @node: device node of the framer
* @ops: function pointers for performing framer operations
*
* Creates a new framer device adding it to the framer class.
* While at that, it also associates the device with the framer using devres.
* On driver detach, release function is invoked on the devres data,
* then, devres data is freed.
*/
struct framer *devm_framer_create(struct device *dev, struct device_node *node,
const struct framer_ops *ops)
{
struct framer **ptr, *framer;
ptr = devres_alloc(devm_framer_destroy, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
framer = framer_create(dev, node, ops);
if (!IS_ERR(framer)) {
*ptr = framer;
devres_add(dev, ptr);
} else {
devres_free(ptr);
}
return framer;
}
EXPORT_SYMBOL_GPL(devm_framer_create);
/**
* framer_provider_simple_of_xlate() - returns the framer instance from framer provider
* @dev: the framer provider device
* @args: of_phandle_args (not used here)
*
* Intended to be used by framer provider for the common case where #framer-cells is
* 0. For other cases where #framer-cells is greater than '0', the framer provider
* should provide a custom of_xlate function that reads the *args* and returns
* the appropriate framer.
*/
struct framer *framer_provider_simple_of_xlate(struct device *dev, struct of_phandle_args *args)
{
struct class_dev_iter iter;
struct framer *framer;
class_dev_iter_init(&iter, framer_class, NULL, NULL);
while ((dev = class_dev_iter_next(&iter))) {
framer = dev_to_framer(dev);
if (args->np != framer->dev.of_node)
continue;
class_dev_iter_exit(&iter);
return framer;
}
class_dev_iter_exit(&iter);
return ERR_PTR(-ENODEV);
}
EXPORT_SYMBOL_GPL(framer_provider_simple_of_xlate);
/**
* __framer_provider_of_register() - create/register framer provider with the framework
* @dev: struct device of the framer provider
* @owner: the module owner containing of_xlate
* @of_xlate: function pointer to obtain framer instance from framer provider
*
* Creates struct framer_provider from dev and of_xlate function pointer.
* This is used in the case of dt boot for finding the framer instance from
* framer provider.
*/
struct framer_provider *
__framer_provider_of_register(struct device *dev, struct module *owner,
struct framer *(*of_xlate)(struct device *dev,
struct of_phandle_args *args))
{
struct framer_provider *framer_provider;
framer_provider = kzalloc(sizeof(*framer_provider), GFP_KERNEL);
if (!framer_provider)
return ERR_PTR(-ENOMEM);
framer_provider->dev = dev;
framer_provider->owner = owner;
framer_provider->of_xlate = of_xlate;
of_node_get(framer_provider->dev->of_node);
mutex_lock(&framer_provider_mutex);
list_add_tail(&framer_provider->list, &framer_provider_list);
mutex_unlock(&framer_provider_mutex);
return framer_provider;
}
EXPORT_SYMBOL_GPL(__framer_provider_of_register);
/**
* framer_provider_of_unregister() - unregister framer provider from the framework
* @framer_provider: framer provider returned by framer_provider_of_register()
*
* Removes the framer_provider created using framer_provider_of_register().
*/
void framer_provider_of_unregister(struct framer_provider *framer_provider)
{
mutex_lock(&framer_provider_mutex);
list_del(&framer_provider->list);
mutex_unlock(&framer_provider_mutex);
of_node_put(framer_provider->dev->of_node);
kfree(framer_provider);
}
EXPORT_SYMBOL_GPL(framer_provider_of_unregister);
static void devm_framer_provider_of_unregister(struct device *dev, void *res)
{
struct framer_provider *framer_provider = *(struct framer_provider **)res;
framer_provider_of_unregister(framer_provider);
}
/**
* __devm_framer_provider_of_register() - create/register framer provider with
* the framework
* @dev: struct device of the framer provider
* @owner: the module owner containing of_xlate
* @of_xlate: function pointer to obtain framer instance from framer provider
*
* Creates struct framer_provider from dev and of_xlate function pointer.
* This is used in the case of dt boot for finding the framer instance from
* framer provider. While at that, it also associates the device with the
* framer provider using devres. On driver detach, release function is invoked
* on the devres data, then, devres data is freed.
*/
struct framer_provider *
__devm_framer_provider_of_register(struct device *dev, struct module *owner,
struct framer *(*of_xlate)(struct device *dev,
struct of_phandle_args *args))
{
struct framer_provider **ptr, *framer_provider;
ptr = devres_alloc(devm_framer_provider_of_unregister, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
framer_provider = __framer_provider_of_register(dev, owner, of_xlate);
if (!IS_ERR(framer_provider)) {
*ptr = framer_provider;
devres_add(dev, ptr);
} else {
devres_free(ptr);
}
return framer_provider;
}
EXPORT_SYMBOL_GPL(__devm_framer_provider_of_register);
/**
* framer_release() - release the framer
* @dev: the dev member within framer
*
* When the last reference to the device is removed, it is called
* from the embedded kobject as release method.
*/
static void framer_release(struct device *dev)
{
struct framer *framer;
framer = dev_to_framer(dev);
regulator_put(framer->pwr);
ida_free(&framer_ida, framer->id);
kfree(framer);
}
static int __init framer_core_init(void)
{
framer_class = class_create("framer");
if (IS_ERR(framer_class)) {
pr_err("failed to create framer class (%pe)\n", framer_class);
return PTR_ERR(framer_class);
}
framer_class->dev_release = framer_release;
return 0;
}
device_initcall(framer_core_init);

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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Generic framer profider header file
*
* Copyright 2023 CS GROUP France
*
* Author: Herve Codina <herve.codina@bootlin.com>
*/
#ifndef __DRIVERS_PROVIDER_FRAMER_H
#define __DRIVERS_PROVIDER_FRAMER_H
#include <linux/export.h>
#include <linux/framer/framer.h>
#include <linux/types.h>
#define FRAMER_FLAG_POLL_STATUS BIT(0)
/**
* struct framer_ops - set of function pointers for performing framer operations
* @init: operation to be performed for initializing the framer
* @exit: operation to be performed while exiting
* @power_on: powering on the framer
* @power_off: powering off the framer
* @flags: OR-ed flags (FRAMER_FLAG_*) to ask for core functionality
* - @FRAMER_FLAG_POLL_STATUS:
* Ask the core to perform a polling to get the framer status and
* notify consumers on change.
* The framer should call @framer_notify_status_change() when it
* detects a status change. This is usually done using interrupts.
* If the framer cannot detect this change, it can ask the core for
* a status polling. The core will call @get_status() periodically
* and, on change detected, it will notify the consumer.
* the @get_status()
* @owner: the module owner containing the ops
*/
struct framer_ops {
int (*init)(struct framer *framer);
void (*exit)(struct framer *framer);
int (*power_on)(struct framer *framer);
int (*power_off)(struct framer *framer);
/**
* @get_status:
*
* Optional.
*
* Used to get the framer status. framer_init() must have
* been called on the framer.
*
* Returns: 0 if successful, an negative error code otherwise
*/
int (*get_status)(struct framer *framer, struct framer_status *status);
/**
* @set_config:
*
* Optional.
*
* Used to set the framer configuration. framer_init() must have
* been called on the framer.
*
* Returns: 0 if successful, an negative error code otherwise
*/
int (*set_config)(struct framer *framer, const struct framer_config *config);
/**
* @get_config:
*
* Optional.
*
* Used to get the framer configuration. framer_init() must have
* been called on the framer.
*
* Returns: 0 if successful, an negative error code otherwise
*/
int (*get_config)(struct framer *framer, struct framer_config *config);
u32 flags;
struct module *owner;
};
/**
* struct framer_provider - represents the framer provider
* @dev: framer provider device
* @children: can be used to override the default (dev->of_node) child node
* @owner: the module owner having of_xlate
* @list: to maintain a linked list of framer providers
* @of_xlate: function pointer to obtain framer instance from framer pointer
*/
struct framer_provider {
struct device *dev;
struct module *owner;
struct list_head list;
struct framer * (*of_xlate)(struct device *dev,
struct of_phandle_args *args);
};
static inline void framer_set_drvdata(struct framer *framer, void *data)
{
dev_set_drvdata(&framer->dev, data);
}
static inline void *framer_get_drvdata(struct framer *framer)
{
return dev_get_drvdata(&framer->dev);
}
#if IS_ENABLED(CONFIG_GENERIC_FRAMER)
/* Create and destroy a framer */
struct framer *framer_create(struct device *dev, struct device_node *node,
const struct framer_ops *ops);
void framer_destroy(struct framer *framer);
/* devm version */
struct framer *devm_framer_create(struct device *dev, struct device_node *node,
const struct framer_ops *ops);
struct framer *framer_provider_simple_of_xlate(struct device *dev,
struct of_phandle_args *args);
struct framer_provider *
__framer_provider_of_register(struct device *dev, struct module *owner,
struct framer *(*of_xlate)(struct device *dev,
struct of_phandle_args *args));
void framer_provider_of_unregister(struct framer_provider *framer_provider);
struct framer_provider *
__devm_framer_provider_of_register(struct device *dev, struct module *owner,
struct framer *(*of_xlate)(struct device *dev,
struct of_phandle_args *args));
void framer_notify_status_change(struct framer *framer);
#else /* IS_ENABLED(CONFIG_GENERIC_FRAMER) */
static inline struct framer *framer_create(struct device *dev, struct device_node *node,
const struct framer_ops *ops)
{
return ERR_PTR(-ENOSYS);
}
static inline void framer_destroy(struct framer *framer)
{
}
/* devm version */
static inline struct framer *devm_framer_create(struct device *dev, struct device_node *node,
const struct framer_ops *ops)
{
return ERR_PTR(-ENOSYS);
}
static inline struct framer *framer_provider_simple_of_xlate(struct device *dev,
struct of_phandle_args *args)
{
return ERR_PTR(-ENOSYS);
}
static inline struct framer_provider *
__framer_provider_of_register(struct device *dev, struct module *owner,
struct framer *(*of_xlate)(struct device *dev,
struct of_phandle_args *args))
{
return ERR_PTR(-ENOSYS);
}
void framer_provider_of_unregister(struct framer_provider *framer_provider)
{
}
static inline struct framer_provider *
__devm_framer_provider_of_register(struct device *dev, struct module *owner,
struct framer *(*of_xlate)(struct device *dev,
struct of_phandle_args *args))
{
return ERR_PTR(-ENOSYS);
}
void framer_notify_status_change(struct framer *framer)
{
}
#endif /* IS_ENABLED(CONFIG_GENERIC_FRAMER) */
#define framer_provider_of_register(dev, xlate) \
__framer_provider_of_register((dev), THIS_MODULE, (xlate))
#define devm_framer_provider_of_register(dev, xlate) \
__devm_framer_provider_of_register((dev), THIS_MODULE, (xlate))
#endif /* __DRIVERS_PROVIDER_FRAMER_H */

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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Generic framer header file
*
* Copyright 2023 CS GROUP France
*
* Author: Herve Codina <herve.codina@bootlin.com>
*/
#ifndef __DRIVERS_FRAMER_H
#define __DRIVERS_FRAMER_H
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/of.h>
#include <linux/device.h>
#include <linux/workqueue.h>
/**
* enum framer_iface - Framer interface
* @FRAMER_IFACE_E1: E1 interface
* @FRAMER_IFACE_T1: T1 interface
*/
enum framer_iface {
FRAMER_IFACE_E1,
FRAMER_IFACE_T1,
};
/**
* enum framer_clock_type - Framer clock type
* @FRAMER_CLOCK_EXT: External clock
* @FRAMER_CLOCK_INT: Internal clock
*/
enum framer_clock_type {
FRAMER_CLOCK_EXT,
FRAMER_CLOCK_INT,
};
/**
* struct framer_config - Framer configuration
* @iface: Framer line interface
* @clock_type: Framer clock type
* @line_clock_rate: Framer line clock rate
*/
struct framer_config {
enum framer_iface iface;
enum framer_clock_type clock_type;
unsigned long line_clock_rate;
};
/**
* struct framer_status - Framer status
* @link_is_on: Framer link state. true, the link is on, false, the link is off.
*/
struct framer_status {
bool link_is_on;
};
/**
* enum framer_event - Event available for notification
* @FRAMER_EVENT_STATUS: Event notified on framer_status changes
*/
enum framer_event {
FRAMER_EVENT_STATUS,
};
/**
* struct framer - represents the framer device
* @dev: framer device
* @id: id of the framer device
* @ops: function pointers for performing framer operations
* @mutex: mutex to protect framer_ops
* @init_count: used to protect when the framer is used by multiple consumers
* @power_count: used to protect when the framer is used by multiple consumers
* @pwr: power regulator associated with the framer
* @notify_status_work: work structure used for status notifications
* @notifier_list: notifier list used for notifications
* @polling_work: delayed work structure used for the polling task
* @prev_status: previous read status used by the polling task to detect changes
*/
struct framer {
struct device dev;
int id;
const struct framer_ops *ops;
struct mutex mutex; /* Protect framer */
int init_count;
int power_count;
struct regulator *pwr;
struct work_struct notify_status_work;
struct blocking_notifier_head notifier_list;
struct delayed_work polling_work;
struct framer_status prev_status;
};
#if IS_ENABLED(CONFIG_GENERIC_FRAMER)
int framer_pm_runtime_get(struct framer *framer);
int framer_pm_runtime_get_sync(struct framer *framer);
int framer_pm_runtime_put(struct framer *framer);
int framer_pm_runtime_put_sync(struct framer *framer);
int framer_init(struct framer *framer);
int framer_exit(struct framer *framer);
int framer_power_on(struct framer *framer);
int framer_power_off(struct framer *framer);
int framer_get_status(struct framer *framer, struct framer_status *status);
int framer_get_config(struct framer *framer, struct framer_config *config);
int framer_set_config(struct framer *framer, const struct framer_config *config);
int framer_notifier_register(struct framer *framer, struct notifier_block *nb);
int framer_notifier_unregister(struct framer *framer, struct notifier_block *nb);
struct framer *framer_get(struct device *dev, const char *con_id);
void framer_put(struct device *dev, struct framer *framer);
struct framer *devm_framer_get(struct device *dev, const char *con_id);
struct framer *devm_framer_optional_get(struct device *dev, const char *con_id);
#else
static inline int framer_pm_runtime_get(struct framer *framer)
{
return -ENOSYS;
}
static inline int framer_pm_runtime_get_sync(struct framer *framer)
{
return -ENOSYS;
}
static inline int framer_pm_runtime_put(struct framer *framer)
{
return -ENOSYS;
}
static inline int framer_pm_runtime_put_sync(struct framer *framer)
{
return -ENOSYS;
}
static inline int framer_init(struct framer *framer)
{
return -ENOSYS;
}
static inline int framer_exit(struct framer *framer)
{
return -ENOSYS;
}
static inline int framer_power_on(struct framer *framer)
{
return -ENOSYS;
}
static inline int framer_power_off(struct framer *framer)
{
return -ENOSYS;
}
static inline int framer_get_status(struct framer *framer, struct framer_status *status)
{
return -ENOSYS;
}
static inline int framer_get_config(struct framer *framer, struct framer_config *config)
{
return -ENOSYS;
}
static inline int framer_set_config(struct framer *framer, const struct framer_config *config)
{
return -ENOSYS;
}
static inline int framer_notifier_register(struct framer *framer,
struct notifier_block *nb)
{
return -ENOSYS;
}
static inline int framer_notifier_unregister(struct framer *framer,
struct notifier_block *nb)
{
return -ENOSYS;
}
struct framer *framer_get(struct device *dev, const char *con_id)
{
return ERR_PTR(-ENOSYS);
}
void framer_put(struct device *dev, struct framer *framer)
{
}
static inline struct framer *devm_framer_get(struct device *dev, const char *con_id)
{
return ERR_PTR(-ENOSYS);
}
static inline struct framer *devm_framer_optional_get(struct device *dev, const char *con_id)
{
return NULL;
}
#endif
#endif /* __DRIVERS_FRAMER_H */