summaryrefslogtreecommitdiff
path: root/drivers/phy/phy-core.c
diff options
context:
space:
mode:
authorKishon Vijay Abraham I <kishon@ti.com>2013-09-27 11:53:25 +0530
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-09-27 17:35:41 -0700
commitff764963479a1b18721ab96e531404c50fefe8b1 (patch)
treee696248868cbb6ab2ac2159058c72631b620b136 /drivers/phy/phy-core.c
parent6741448eb01a1844b78c83fa8faf0c95524fc09b (diff)
drivers: phy: add generic PHY framework
The PHY framework provides a set of APIs for the PHY drivers to create/destroy a PHY and APIs for the PHY users to obtain a reference to the PHY with or without using phandle. For dt-boot, the PHY drivers should also register *PHY provider* with the framework. PHY drivers should create the PHY by passing id and ops like init, exit, power_on and power_off. This framework is also pm runtime enabled. The documentation for the generic PHY framework is added in Documentation/phy.txt and the documentation for dt binding can be found at Documentation/devicetree/bindings/phy/phy-bindings.txt Cc: Tomasz Figa <t.figa@samsung.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com> Acked-by: Felipe Balbi <balbi@ti.com> Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/phy/phy-core.c')
-rw-r--r--drivers/phy/phy-core.c698
1 files changed, 698 insertions, 0 deletions
diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
new file mode 100644
index 000000000000..03cf8fb81554
--- /dev/null
+++ b/drivers/phy/phy-core.c
@@ -0,0 +1,698 @@
+/*
+ * phy-core.c -- Generic Phy framework.
+ *
+ * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * Author: Kishon Vijay Abraham I <kishon@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/idr.h>
+#include <linux/pm_runtime.h>
+
+static struct class *phy_class;
+static DEFINE_MUTEX(phy_provider_mutex);
+static LIST_HEAD(phy_provider_list);
+static DEFINE_IDA(phy_ida);
+
+static void devm_phy_release(struct device *dev, void *res)
+{
+ struct phy *phy = *(struct phy **)res;
+
+ phy_put(phy);
+}
+
+static void devm_phy_provider_release(struct device *dev, void *res)
+{
+ struct phy_provider *phy_provider = *(struct phy_provider **)res;
+
+ of_phy_provider_unregister(phy_provider);
+}
+
+static void devm_phy_consume(struct device *dev, void *res)
+{
+ struct phy *phy = *(struct phy **)res;
+
+ phy_destroy(phy);
+}
+
+static int devm_phy_match(struct device *dev, void *res, void *match_data)
+{
+ return res == match_data;
+}
+
+static struct phy *phy_lookup(struct device *device, const char *port)
+{
+ unsigned int count;
+ struct phy *phy;
+ struct device *dev;
+ struct phy_consumer *consumers;
+ struct class_dev_iter iter;
+
+ class_dev_iter_init(&iter, phy_class, NULL, NULL);
+ while ((dev = class_dev_iter_next(&iter))) {
+ phy = to_phy(dev);
+ count = phy->init_data->num_consumers;
+ consumers = phy->init_data->consumers;
+ while (count--) {
+ if (!strcmp(consumers->dev_name, dev_name(device)) &&
+ !strcmp(consumers->port, port)) {
+ class_dev_iter_exit(&iter);
+ return phy;
+ }
+ consumers++;
+ }
+ }
+
+ class_dev_iter_exit(&iter);
+ return ERR_PTR(-ENODEV);
+}
+
+static struct phy_provider *of_phy_provider_lookup(struct device_node *node)
+{
+ struct phy_provider *phy_provider;
+
+ list_for_each_entry(phy_provider, &phy_provider_list, list) {
+ if (phy_provider->dev->of_node == node)
+ return phy_provider;
+ }
+
+ return ERR_PTR(-EPROBE_DEFER);
+}
+
+int phy_pm_runtime_get(struct phy *phy)
+{
+ if (!pm_runtime_enabled(&phy->dev))
+ return -ENOTSUPP;
+
+ return pm_runtime_get(&phy->dev);
+}
+EXPORT_SYMBOL_GPL(phy_pm_runtime_get);
+
+int phy_pm_runtime_get_sync(struct phy *phy)
+{
+ if (!pm_runtime_enabled(&phy->dev))
+ return -ENOTSUPP;
+
+ return pm_runtime_get_sync(&phy->dev);
+}
+EXPORT_SYMBOL_GPL(phy_pm_runtime_get_sync);
+
+int phy_pm_runtime_put(struct phy *phy)
+{
+ if (!pm_runtime_enabled(&phy->dev))
+ return -ENOTSUPP;
+
+ return pm_runtime_put(&phy->dev);
+}
+EXPORT_SYMBOL_GPL(phy_pm_runtime_put);
+
+int phy_pm_runtime_put_sync(struct phy *phy)
+{
+ if (!pm_runtime_enabled(&phy->dev))
+ return -ENOTSUPP;
+
+ return pm_runtime_put_sync(&phy->dev);
+}
+EXPORT_SYMBOL_GPL(phy_pm_runtime_put_sync);
+
+void phy_pm_runtime_allow(struct phy *phy)
+{
+ if (!pm_runtime_enabled(&phy->dev))
+ return;
+
+ pm_runtime_allow(&phy->dev);
+}
+EXPORT_SYMBOL_GPL(phy_pm_runtime_allow);
+
+void phy_pm_runtime_forbid(struct phy *phy)
+{
+ if (!pm_runtime_enabled(&phy->dev))
+ return;
+
+ pm_runtime_forbid(&phy->dev);
+}
+EXPORT_SYMBOL_GPL(phy_pm_runtime_forbid);
+
+int phy_init(struct phy *phy)
+{
+ int ret;
+
+ ret = phy_pm_runtime_get_sync(phy);
+ if (ret < 0 && ret != -ENOTSUPP)
+ return ret;
+
+ mutex_lock(&phy->mutex);
+ if (phy->init_count++ == 0 && phy->ops->init) {
+ ret = phy->ops->init(phy);
+ if (ret < 0) {
+ dev_err(&phy->dev, "phy init failed --> %d\n", ret);
+ goto out;
+ }
+ }
+
+out:
+ mutex_unlock(&phy->mutex);
+ phy_pm_runtime_put(phy);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(phy_init);
+
+int phy_exit(struct phy *phy)
+{
+ int ret;
+
+ ret = phy_pm_runtime_get_sync(phy);
+ if (ret < 0 && ret != -ENOTSUPP)
+ return ret;
+
+ mutex_lock(&phy->mutex);
+ if (--phy->init_count == 0 && phy->ops->exit) {
+ ret = phy->ops->exit(phy);
+ if (ret < 0) {
+ dev_err(&phy->dev, "phy exit failed --> %d\n", ret);
+ goto out;
+ }
+ }
+
+out:
+ mutex_unlock(&phy->mutex);
+ phy_pm_runtime_put(phy);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(phy_exit);
+
+int phy_power_on(struct phy *phy)
+{
+ int ret = -ENOTSUPP;
+
+ ret = phy_pm_runtime_get_sync(phy);
+ if (ret < 0 && ret != -ENOTSUPP)
+ return ret;
+
+ mutex_lock(&phy->mutex);
+ if (phy->power_count++ == 0 && phy->ops->power_on) {
+ ret = phy->ops->power_on(phy);
+ if (ret < 0) {
+ dev_err(&phy->dev, "phy poweron failed --> %d\n", ret);
+ goto out;
+ }
+ }
+
+out:
+ mutex_unlock(&phy->mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(phy_power_on);
+
+int phy_power_off(struct phy *phy)
+{
+ int ret = -ENOTSUPP;
+
+ mutex_lock(&phy->mutex);
+ if (--phy->power_count == 0 && phy->ops->power_off) {
+ ret = phy->ops->power_off(phy);
+ if (ret < 0) {
+ dev_err(&phy->dev, "phy poweroff failed --> %d\n", ret);
+ goto out;
+ }
+ }
+
+out:
+ mutex_unlock(&phy->mutex);
+ phy_pm_runtime_put(phy);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(phy_power_off);
+
+/**
+ * of_phy_get() - lookup and obtain a reference to a phy by phandle
+ * @dev: device that requests this phy
+ * @index: the index of the phy
+ *
+ * Returns the phy associated with the given phandle value,
+ * after getting a refcount to it or -ENODEV if there is no such phy or
+ * -EPROBE_DEFER if there is a phandle to the phy, but the device is
+ * not yet loaded. This function uses of_xlate call back function provided
+ * while registering the phy_provider to find the phy instance.
+ */
+static struct phy *of_phy_get(struct device *dev, int index)
+{
+ int ret;
+ struct phy_provider *phy_provider;
+ struct phy *phy = NULL;
+ struct of_phandle_args args;
+
+ ret = of_parse_phandle_with_args(dev->of_node, "phys", "#phy-cells",
+ index, &args);
+ if (ret) {
+ dev_dbg(dev, "failed to get phy in %s node\n",
+ dev->of_node->full_name);
+ return ERR_PTR(-ENODEV);
+ }
+
+ mutex_lock(&phy_provider_mutex);
+ phy_provider = of_phy_provider_lookup(args.np);
+ if (IS_ERR(phy_provider) || !try_module_get(phy_provider->owner)) {
+ phy = ERR_PTR(-EPROBE_DEFER);
+ goto err0;
+ }
+
+ phy = phy_provider->of_xlate(phy_provider->dev, &args);
+ module_put(phy_provider->owner);
+
+err0:
+ mutex_unlock(&phy_provider_mutex);
+ of_node_put(args.np);
+
+ return phy;
+}
+
+/**
+ * phy_put() - release the PHY
+ * @phy: the phy returned by phy_get()
+ *
+ * Releases a refcount the caller received from phy_get().
+ */
+void phy_put(struct phy *phy)
+{
+ if (IS_ERR(phy))
+ return;
+
+ module_put(phy->ops->owner);
+ put_device(&phy->dev);
+}
+EXPORT_SYMBOL_GPL(phy_put);
+
+/**
+ * devm_phy_put() - release the PHY
+ * @dev: device that wants to release this phy
+ * @phy: the phy returned by devm_phy_get()
+ *
+ * destroys the devres associated with this phy and invokes phy_put
+ * to release the phy.
+ */
+void devm_phy_put(struct device *dev, struct phy *phy)
+{
+ int r;
+
+ r = devres_destroy(dev, devm_phy_release, devm_phy_match, phy);
+ dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
+}
+EXPORT_SYMBOL_GPL(devm_phy_put);
+
+/**
+ * of_phy_simple_xlate() - returns the phy instance from phy provider
+ * @dev: the PHY provider device
+ * @args: of_phandle_args (not used here)
+ *
+ * Intended to be used by phy provider for the common case where #phy-cells is
+ * 0. For other cases where #phy-cells is greater than '0', the phy provider
+ * should provide a custom of_xlate function that reads the *args* and returns
+ * the appropriate phy.
+ */
+struct phy *of_phy_simple_xlate(struct device *dev, struct of_phandle_args
+ *args)
+{
+ struct phy *phy;
+ struct class_dev_iter iter;
+ struct device_node *node = dev->of_node;
+
+ class_dev_iter_init(&iter, phy_class, NULL, NULL);
+ while ((dev = class_dev_iter_next(&iter))) {
+ phy = to_phy(dev);
+ if (node != phy->dev.of_node)
+ continue;
+
+ class_dev_iter_exit(&iter);
+ return phy;
+ }
+
+ class_dev_iter_exit(&iter);
+ return ERR_PTR(-ENODEV);
+}
+EXPORT_SYMBOL_GPL(of_phy_simple_xlate);
+
+/**
+ * phy_get() - lookup and obtain a reference to a phy.
+ * @dev: device that requests this phy
+ * @string: the phy name as given in the dt data or the name of the controller
+ * port for non-dt case
+ *
+ * Returns the phy driver, after getting a refcount to it; or
+ * -ENODEV if there is no such phy. The caller is responsible for
+ * calling phy_put() to release that count.
+ */
+struct phy *phy_get(struct device *dev, const char *string)
+{
+ int index = 0;
+ struct phy *phy = NULL;
+
+ if (string == NULL) {
+ dev_WARN(dev, "missing string\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (dev->of_node) {
+ index = of_property_match_string(dev->of_node, "phy-names",
+ string);
+ phy = of_phy_get(dev, index);
+ if (IS_ERR(phy)) {
+ dev_err(dev, "unable to find phy\n");
+ return phy;
+ }
+ } else {
+ phy = phy_lookup(dev, string);
+ if (IS_ERR(phy)) {
+ dev_err(dev, "unable to find phy\n");
+ return phy;
+ }
+ }
+
+ if (!try_module_get(phy->ops->owner))
+ return ERR_PTR(-EPROBE_DEFER);
+
+ get_device(&phy->dev);
+
+ return phy;
+}
+EXPORT_SYMBOL_GPL(phy_get);
+
+/**
+ * devm_phy_get() - lookup and obtain a reference to a phy.
+ * @dev: device that requests this phy
+ * @string: the phy name as given in the dt data or phy device name
+ * for non-dt case
+ *
+ * Gets the phy using phy_get(), and associates a device with it using
+ * devres. On driver detach, release function is invoked on the devres data,
+ * then, devres data is freed.
+ */
+struct phy *devm_phy_get(struct device *dev, const char *string)
+{
+ struct phy **ptr, *phy;
+
+ ptr = devres_alloc(devm_phy_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ phy = phy_get(dev, string);
+ if (!IS_ERR(phy)) {
+ *ptr = phy;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return phy;
+}
+EXPORT_SYMBOL_GPL(devm_phy_get);
+
+/**
+ * phy_create() - create a new phy
+ * @dev: device that is creating the new phy
+ * @ops: function pointers for performing phy operations
+ * @init_data: contains the list of PHY consumers or NULL
+ *
+ * Called to create a phy using phy framework.
+ */
+struct phy *phy_create(struct device *dev, const struct phy_ops *ops,
+ struct phy_init_data *init_data)
+{
+ int ret;
+ int id;
+ struct phy *phy;
+
+ if (!dev) {
+ dev_WARN(dev, "no device provided for PHY\n");
+ ret = -EINVAL;
+ goto err0;
+ }
+
+ phy = kzalloc(sizeof(*phy), GFP_KERNEL);
+ if (!phy) {
+ ret = -ENOMEM;
+ goto err0;
+ }
+
+ id = ida_simple_get(&phy_ida, 0, 0, GFP_KERNEL);
+ if (id < 0) {
+ dev_err(dev, "unable to get id\n");
+ ret = id;
+ goto err0;
+ }
+
+ device_initialize(&phy->dev);
+ mutex_init(&phy->mutex);
+
+ phy->dev.class = phy_class;
+ phy->dev.parent = dev;
+ phy->dev.of_node = dev->of_node;
+ phy->id = id;
+ phy->ops = ops;
+ phy->init_data = init_data;
+
+ ret = dev_set_name(&phy->dev, "phy-%s.%d", dev_name(dev), id);
+ if (ret)
+ goto err1;
+
+ ret = device_add(&phy->dev);
+ if (ret)
+ goto err1;
+
+ if (pm_runtime_enabled(dev)) {
+ pm_runtime_enable(&phy->dev);
+ pm_runtime_no_callbacks(&phy->dev);
+ }
+
+ return phy;
+
+err1:
+ ida_remove(&phy_ida, phy->id);
+ put_device(&phy->dev);
+ kfree(phy);
+
+err0:
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(phy_create);
+
+/**
+ * devm_phy_create() - create a new phy
+ * @dev: device that is creating the new phy
+ * @ops: function pointers for performing phy operations
+ * @init_data: contains the list of PHY consumers or NULL
+ *
+ * Creates a new PHY device adding it to the PHY class.
+ * While at that, it also associates the device with the phy using devres.
+ * On driver detach, release function is invoked on the devres data,
+ * then, devres data is freed.
+ */
+struct phy *devm_phy_create(struct device *dev, const struct phy_ops *ops,
+ struct phy_init_data *init_data)
+{
+ struct phy **ptr, *phy;
+
+ ptr = devres_alloc(devm_phy_consume, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ phy = phy_create(dev, ops, init_data);
+ if (!IS_ERR(phy)) {
+ *ptr = phy;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return phy;
+}
+EXPORT_SYMBOL_GPL(devm_phy_create);
+
+/**
+ * phy_destroy() - destroy the phy
+ * @phy: the phy to be destroyed
+ *
+ * Called to destroy the phy.
+ */
+void phy_destroy(struct phy *phy)
+{
+ pm_runtime_disable(&phy->dev);
+ device_unregister(&phy->dev);
+}
+EXPORT_SYMBOL_GPL(phy_destroy);
+
+/**
+ * devm_phy_destroy() - destroy the PHY
+ * @dev: device that wants to release this phy
+ * @phy: the phy returned by devm_phy_get()
+ *
+ * destroys the devres associated with this phy and invokes phy_destroy
+ * to destroy the phy.
+ */
+void devm_phy_destroy(struct device *dev, struct phy *phy)
+{
+ int r;
+
+ r = devres_destroy(dev, devm_phy_consume, devm_phy_match, phy);
+ dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
+}
+EXPORT_SYMBOL_GPL(devm_phy_destroy);
+
+/**
+ * __of_phy_provider_register() - create/register phy provider with the framework
+ * @dev: struct device of the phy provider
+ * @owner: the module owner containing of_xlate
+ * @of_xlate: function pointer to obtain phy instance from phy provider
+ *
+ * Creates struct phy_provider from dev and of_xlate function pointer.
+ * This is used in the case of dt boot for finding the phy instance from
+ * phy provider.
+ */
+struct phy_provider *__of_phy_provider_register(struct device *dev,
+ struct module *owner, struct phy * (*of_xlate)(struct device *dev,
+ struct of_phandle_args *args))
+{
+ struct phy_provider *phy_provider;
+
+ phy_provider = kzalloc(sizeof(*phy_provider), GFP_KERNEL);
+ if (!phy_provider)
+ return ERR_PTR(-ENOMEM);
+
+ phy_provider->dev = dev;
+ phy_provider->owner = owner;
+ phy_provider->of_xlate = of_xlate;
+
+ mutex_lock(&phy_provider_mutex);
+ list_add_tail(&phy_provider->list, &phy_provider_list);
+ mutex_unlock(&phy_provider_mutex);
+
+ return phy_provider;
+}
+EXPORT_SYMBOL_GPL(__of_phy_provider_register);
+
+/**
+ * __devm_of_phy_provider_register() - create/register phy provider with the
+ * framework
+ * @dev: struct device of the phy provider
+ * @owner: the module owner containing of_xlate
+ * @of_xlate: function pointer to obtain phy instance from phy provider
+ *
+ * Creates struct phy_provider from dev and of_xlate function pointer.
+ * This is used in the case of dt boot for finding the phy instance from
+ * phy provider. While at that, it also associates the device with the
+ * phy provider using devres. On driver detach, release function is invoked
+ * on the devres data, then, devres data is freed.
+ */
+struct phy_provider *__devm_of_phy_provider_register(struct device *dev,
+ struct module *owner, struct phy * (*of_xlate)(struct device *dev,
+ struct of_phandle_args *args))
+{
+ struct phy_provider **ptr, *phy_provider;
+
+ ptr = devres_alloc(devm_phy_provider_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ phy_provider = __of_phy_provider_register(dev, owner, of_xlate);
+ if (!IS_ERR(phy_provider)) {
+ *ptr = phy_provider;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return phy_provider;
+}
+EXPORT_SYMBOL_GPL(__devm_of_phy_provider_register);
+
+/**
+ * of_phy_provider_unregister() - unregister phy provider from the framework
+ * @phy_provider: phy provider returned by of_phy_provider_register()
+ *
+ * Removes the phy_provider created using of_phy_provider_register().
+ */
+void of_phy_provider_unregister(struct phy_provider *phy_provider)
+{
+ if (IS_ERR(phy_provider))
+ return;
+
+ mutex_lock(&phy_provider_mutex);
+ list_del(&phy_provider->list);
+ kfree(phy_provider);
+ mutex_unlock(&phy_provider_mutex);
+}
+EXPORT_SYMBOL_GPL(of_phy_provider_unregister);
+
+/**
+ * devm_of_phy_provider_unregister() - remove phy provider from the framework
+ * @dev: struct device of the phy provider
+ *
+ * destroys the devres associated with this phy provider and invokes
+ * of_phy_provider_unregister to unregister the phy provider.
+ */
+void devm_of_phy_provider_unregister(struct device *dev,
+ struct phy_provider *phy_provider) {
+ int r;
+
+ r = devres_destroy(dev, devm_phy_provider_release, devm_phy_match,
+ phy_provider);
+ dev_WARN_ONCE(dev, r, "couldn't find PHY provider device resource\n");
+}
+EXPORT_SYMBOL_GPL(devm_of_phy_provider_unregister);
+
+/**
+ * phy_release() - release the phy
+ * @dev: the dev member within phy
+ *
+ * When the last reference to the device is removed, it is called
+ * from the embedded kobject as release method.
+ */
+static void phy_release(struct device *dev)
+{
+ struct phy *phy;
+
+ phy = to_phy(dev);
+ dev_vdbg(dev, "releasing '%s'\n", dev_name(dev));
+ ida_remove(&phy_ida, phy->id);
+ kfree(phy);
+}
+
+static int __init phy_core_init(void)
+{
+ phy_class = class_create(THIS_MODULE, "phy");
+ if (IS_ERR(phy_class)) {
+ pr_err("failed to create phy class --> %ld\n",
+ PTR_ERR(phy_class));
+ return PTR_ERR(phy_class);
+ }
+
+ phy_class->dev_release = phy_release;
+
+ return 0;
+}
+module_init(phy_core_init);
+
+static void __exit phy_core_exit(void)
+{
+ class_destroy(phy_class);
+}
+module_exit(phy_core_exit);
+
+MODULE_DESCRIPTION("Generic PHY Framework");
+MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
+MODULE_LICENSE("GPL v2");