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 Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx> Tested-by: Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx> --- .../devicetree/bindings/phy/phy-bindings.txt | 66 +++ Documentation/phy.txt | 125 +++++ MAINTAINERS | 7 + drivers/Kconfig | 2 + drivers/Makefile | 2 + drivers/phy/Kconfig | 13 + drivers/phy/Makefile | 5 + drivers/phy/phy-core.c | 548 ++++++++++++++++++++ include/linux/phy/phy.h | 334 ++++++++++++ 9 files changed, 1102 insertions(+) create mode 100644 Documentation/devicetree/bindings/phy/phy-bindings.txt create mode 100644 Documentation/phy.txt create mode 100644 drivers/phy/Kconfig create mode 100644 drivers/phy/Makefile create mode 100644 drivers/phy/phy-core.c create mode 100644 include/linux/phy/phy.h diff --git a/Documentation/devicetree/bindings/phy/phy-bindings.txt b/Documentation/devicetree/bindings/phy/phy-bindings.txt new file mode 100644 index 0000000..8ae844f --- /dev/null +++ b/Documentation/devicetree/bindings/phy/phy-bindings.txt @@ -0,0 +1,66 @@ +This document explains only the device tree data binding. For general +information about PHY subsystem refer to Documentation/phy.txt + +PHY device node +=============== + +Required Properties: +#phy-cells: Number of cells in a PHY specifier; The meaning of all those + cells is defined by the binding for the phy node. The PHY + provider can use the values in cells to find the appropriate + PHY. + +For example: + +phys: phy { + compatible = "xxx"; + reg = <...>; + . + . + #phy-cells = <1>; + . + . +}; + +That node describes an IP block (PHY provider) that implements 2 different PHYs. +In order to differentiate between these 2 PHYs, an additonal specifier should be +given while trying to get a reference to it. + +PHY user node +============= + +Required Properties: +phys : the phandle for the PHY device (used by the PHY subsystem) +phy-names : the names of the PHY corresponding to the PHYs present in the + *phys* phandle + +Example 1: +usb1: usb_otg_ss@xxx { + compatible = "xxx"; + reg = <xxx>; + . + . + phys = <&usb2_phy>, <&usb3_phy>; + phy-names = "usb2phy", "usb3phy"; + . + . +}; + +This node represents a controller that uses two PHYs, one for usb2 and one for +usb3. + +Example 2: +usb2: usb_otg_ss@xxx { + compatible = "xxx"; + reg = <xxx>; + . + . + phys = <&phys 1>; + phy-names = "usbphy"; + . + . +}; + +This node represents a controller that uses one of the PHYs of the PHY provider +device defined previously. Note that the phy handle has an additional specifier +"1" to differentiate between the two PHYs. diff --git a/Documentation/phy.txt b/Documentation/phy.txt new file mode 100644 index 0000000..d66ddcc --- /dev/null +++ b/Documentation/phy.txt @@ -0,0 +1,125 @@ + PHY SUBSYSTEM + Kishon Vijay Abraham I <kishon@xxxxxx> + +This document explains the Generic PHY Framework along with the APIs provided, +and how-to-use. + +1. Introduction + +*PHY* is the abbreviation for physical layer. It is used to connect a device +to the physical medium e.g., the USB controller has a PHY to provide functions +such as serialization, de-serialization, encoding, decoding and is responsible +for obtaining the required data transmission rate. Note that some USB +controllers have PHY functionality embedded into it and others use an external +PHY. Other peripherals that use PHY include Wireless LAN, Ethernet, +SATA etc. + +The intention of creating this framework is to bring the PHY drivers spread +all over the Linux kernel to drivers/phy to increase code re-use and for +better code maintainability. + +This framework will be of use only to devices that use external PHY (PHY +functionality is not embedded within the controller). + +2. Registering/Unregistering the PHY provider + +PHY provider refers to an entity that implements one or more PHY instances. +For the simple case where the PHY provider implements only a single instance of +the PHY, the framework provides its own implementation of of_xlate in +of_phy_simple_xlate. If the PHY provider implements multiple instances, it +should provide its own implementation of of_xlate. of_xlate is used only for +dt boot case. + +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 *__devm_of_phy_provider_register(struct device *dev, + struct module *owner, struct phy * (*of_xlate)(struct device *dev, + struct of_phandle_args *args)) + +__of_phy_provider_register and __devm_of_phy_provider_register can be used to +register the phy_provider and it takes device, owner and of_xlate as +arguments. For the dt boot case, all PHY providers should use one of the above +2 APIs to register the PHY provider. + +void devm_of_phy_provider_unregister(struct device *dev, + struct phy_provider *phy_provider); +void of_phy_provider_unregister(struct phy_provider *phy_provider); + +devm_of_phy_provider_unregister and of_phy_provider_unregister can be used to +unregister the PHY. + +3. Creating the PHY + +The PHY driver should create the PHY in order for other peripheral controllers +to make use of it. The PHY framework provides 2 APIs to create the PHY. + +struct phy *phy_create(struct device *dev, u8 id, const struct phy_ops *ops, + const char *label, void *priv); +extern struct phy *devm_phy_create(struct device *dev, u8 id, + const struct phy_ops *ops, const char *label, void *priv); + +The PHY drivers can use one of the above 2 APIs to create the PHY by passing +the device pointer, id, phy ops, label and a driver data. +phy_ops is a set of function pointers for performing PHY operations such as +init, exit, power_on and power_off. *label* is mandatory for non-dt boot case +and it should be unique as well. + +4. Getting a reference to the PHY + +Before the controller can make use of the PHY, it has to get a reference to +it. This framework provides the following APIs to get a reference to the PHY. + +struct phy *phy_get(struct device *dev, const char *string); +struct phy *devm_phy_get(struct device *dev, const char *string); + +phy_get and devm_phy_get can be used to get the PHY. In the case of dt boot, +the string arguments should contain the phy name as given in the dt data and +in the case of non-dt boot, it should contain the label of the PHY. +The only difference between the two APIs is that devm_phy_get associates the +device with the PHY using devres on successful PHY get. On driver detach, +release function is invoked on the the devres data and devres data is freed. + +5. Releasing a reference to the PHY + +When the controller no longer needs the PHY, it has to release the reference +to the PHY it has obtained using the APIs mentioned in the above section. The +PHY framework provides 2 APIs to release a reference to the PHY. + +void phy_put(struct phy *phy); +void devm_phy_put(struct device *dev, struct phy *phy); + +Both these APIs are used to release a reference to the PHY and devm_phy_put +destroys the devres associated with this PHY. + +6. Destroying the PHY + +When the driver that created the PHY is unloaded, it should destroy the PHY it +created using one of the following 2 APIs. + +void phy_destroy(struct phy *phy); +void devm_phy_destroy(struct device *dev, struct phy *phy); + +Both these APIs destroy the PHY and devm_phy_destroy destroys the devres +associated with this PHY. + +7. PM Runtime + +This subsystem is pm runtime enabled. So while creating the PHY, +pm_runtime_enable of the phy device created by this subsystem is called and +while destroying the PHY, pm_runtime_disable is called. Note that the phy +device created by this subsystem will be a child of the device that calls +phy_create (PHY provider device). + +So pm_runtime_get_sync of the phy_device created by this subsystem will invoke +pm_runtime_get_sync of PHY provider device because of parent-child relationship. +It should also be noted that phy_power_on and phy_power_off performs +phy_pm_runtime_get_sync and phy_pm_runtime_put respectively. +There are exported APIs like phy_pm_runtime_get, phy_pm_runtime_get_sync, +phy_pm_runtime_put, phy_pm_runtime_put_sync, phy_pm_runtime_allow and +phy_pm_runtime_forbid for performing PM operations. + +8. DeviceTree Binding + +The documentation for PHY dt binding can be found @ +Documentation/devicetree/bindings/phy/phy-bindings.txt diff --git a/MAINTAINERS b/MAINTAINERS index 0c9dc71..c234461 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3536,6 +3536,13 @@ S: Maintained F: include/asm-generic F: include/uapi/asm-generic +GENERIC PHY FRAMEWORK +M: Kishon Vijay Abraham I <kishon@xxxxxx> +L: linux-kernel@xxxxxxxxxxxxxxx +S: Supported +F: drivers/phy/ +F: include/linux/phy/ + GENERIC UIO DRIVER FOR PCI DEVICES M: "Michael S. Tsirkin" <mst@xxxxxxxxxx> L: kvm@xxxxxxxxxxxxxxx diff --git a/drivers/Kconfig b/drivers/Kconfig index 9953a42..2943fb6 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -166,4 +166,6 @@ source "drivers/ipack/Kconfig" source "drivers/reset/Kconfig" +source "drivers/phy/Kconfig" + endmenu diff --git a/drivers/Makefile b/drivers/Makefile index 130abc1..46c99a1 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -8,6 +8,8 @@ obj-y += irqchip/ obj-y += bus/ +obj-$(CONFIG_GENERIC_PHY) += phy/ + # GPIO must come after pinctrl as gpios may need to mux pins etc obj-y += pinctrl/ obj-y += gpio/ diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig new file mode 100644 index 0000000..5f85909 --- /dev/null +++ b/drivers/phy/Kconfig @@ -0,0 +1,13 @@ +# +# PHY +# + +menuconfig GENERIC_PHY + tristate "PHY Subsystem" + help + Generic PHY support. + + This framework is designed to provide a generic interface for PHY + devices present in the kernel. This layer will have the generic + API by which phy drivers can create PHY using the phy framework and + phy users can obtain reference to the PHY. diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile new file mode 100644 index 0000000..9e9560f --- /dev/null +++ b/drivers/phy/Makefile @@ -0,0 +1,5 @@ +# +# Makefile for the phy drivers. +# + +obj-$(CONFIG_GENERIC_PHY) += phy-core.o diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c new file mode 100644 index 0000000..1c2439d --- /dev/null +++ b/drivers/phy/phy-core.c @@ -0,0 +1,548 @@ +/* + * phy-core.c -- Generic Phy framework. + * + * Copyright (C) 2013 Texas Instruments + * + * Author: Kishon Vijay Abraham I <kishon@xxxxxx> + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#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/pm_runtime.h> + +static struct class *phy_class; +static DEFINE_MUTEX(phy_provider_mutex); +static LIST_HEAD(phy_provider_list); + +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(const char *phy_name) +{ + struct phy *phy; + struct device *dev; + 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); + if (strcmp(phy->label, phy_name)) + continue; + + class_dev_iter_exit(&iter); + return phy; + } + + 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); +} + +/** + * 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 phy device name + * 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_WARN(dev, "unable to find phy\n"); + return phy; + } + } else { + phy = phy_lookup(string); + if (IS_ERR(phy)) { + dev_WARN(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 + * @id: id of the phy + * @ops: function pointers for performing phy operations + * @label: label given to the phy + * @priv: private data from phy driver + * + * Called to create a phy using phy framework. + */ +struct phy *phy_create(struct device *dev, u8 id, const struct phy_ops *ops, + const char *label, void *priv) +{ + int ret; + 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; + } + + 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->label = kstrdup(label, GFP_KERNEL); + + dev_set_drvdata(&phy->dev, priv); + + ret = dev_set_name(&phy->dev, "%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: + put_device(&phy->dev); + kfree(phy->label); + 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 + * @id: id of the phy + * @ops: function pointers for performing phy operations + * @label: label given to the phy + * @priv: private data from phy driver + * + * 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, u8 id, + const struct phy_ops *ops, const char *label, void *priv) +{ + struct phy **ptr, *phy; + + ptr = devres_alloc(devm_phy_consume, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + phy = phy_create(dev, id, ops, label, priv); + 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)); + kfree(phy->label); + 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@xxxxxx>"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h new file mode 100644 index 0000000..7abf573 --- /dev/null +++ b/include/linux/phy/phy.h @@ -0,0 +1,334 @@ +/* + * phy.h -- generic phy header file + * + * Copyright (C) 2013 Texas Instruments Incorporated - http://www.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. + * + * Author: Kishon Vijay Abraham I <kishon@xxxxxx> + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#ifndef __DRIVERS_PHY_H +#define __DRIVERS_PHY_H + +#include <linux/err.h> +#include <linux/of.h> +#include <linux/device.h> +#include <linux/pm_runtime.h> + +struct phy; + +/** + * struct phy_ops - set of function pointers for performing phy operations + * @init: operation to be performed for initializing phy + * @exit: operation to be performed while exiting + * @power_on: powering on the phy + * @power_off: powering off the phy + * @owner: the module owner containing the ops + */ +struct phy_ops { + int (*init)(struct phy *phy); + int (*exit)(struct phy *phy); + int (*power_on)(struct phy *phy); + int (*power_off)(struct phy *phy); + struct module *owner; +}; + +/** + * struct phy - represents the phy device + * @dev: phy device + * @id: id of the phy + * @ops: function pointers for performing phy operations + * @label: label given to the phy + * @mutex: mutex to protect phy_ops + * @init_count: used to protect when the PHY is used by multiple consumers + * @power_count: used to protect when the PHY is used by multiple consumers + */ +struct phy { + struct device dev; + int id; + const struct phy_ops *ops; + const char *label; + struct mutex mutex; + int init_count; + int power_count; +}; + +/** + * struct phy_provider - represents the phy provider + * @dev: phy provider device + * @owner: the module owner having of_xlate + * @of_xlate: function pointer to obtain phy instance from phy pointer + * @list: to maintain a linked list of PHY providers + */ +struct phy_provider { + struct device *dev; + struct module *owner; + struct list_head list; + struct phy * (*of_xlate)(struct device *dev, + struct of_phandle_args *args); +}; + +#define to_phy(dev) (container_of((dev), struct phy, dev)) + +#define of_phy_provider_register(dev, xlate) \ + __of_phy_provider_register((dev), THIS_MODULE, (xlate)) + +#define devm_of_phy_provider_register(dev, xlate) \ + __of_phy_provider_register((dev), THIS_MODULE, (xlate)) + +#if IS_ENABLED(CONFIG_GENERIC_PHY) +extern struct phy *phy_get(struct device *dev, const char *string); +extern struct phy *devm_phy_get(struct device *dev, const char *string); +extern void phy_put(struct phy *phy); +extern void devm_phy_put(struct device *dev, struct phy *phy); +extern struct phy *of_phy_simple_xlate(struct device *dev, + struct of_phandle_args *args); +extern struct phy *phy_create(struct device *dev, u8 id, + const struct phy_ops *ops, const char *label, void *priv); +extern struct phy *devm_phy_create(struct device *dev, u8 id, + const struct phy_ops *ops, const char *label, void *priv); +extern void phy_destroy(struct phy *phy); +extern void devm_phy_destroy(struct device *dev, struct phy *phy); +extern 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)); +extern 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)); +extern void of_phy_provider_unregister(struct phy_provider *phy_provider); +extern void devm_of_phy_provider_unregister(struct device *dev, + struct phy_provider *phy_provider); +#else +static inline struct phy *phy_get(struct device *dev, const char *string) +{ + return ERR_PTR(-ENOSYS); +} + +static inline struct phy *devm_phy_get(struct device *dev, const char *string) +{ + return ERR_PTR(-ENOSYS); +} + +static inline void phy_put(struct phy *phy) +{ +} + +static inline void devm_phy_put(struct device *dev, struct phy *phy) +{ +} + +static inline struct phy *of_phy_simple_xlate(struct device *dev, + struct of_phandle_args *args) +{ + return ERR_PTR(-ENOSYS); +} + +static inline struct phy *phy_create(struct device *dev, u8 id, + const struct phy_ops *ops, const char *label, void *priv) +{ + return ERR_PTR(-ENOSYS); +} + +static inline struct phy *devm_phy_create(struct device *dev, u8 id, + const struct phy_ops *ops, const char *label, void *priv) +{ + return ERR_PTR(-ENOSYS); +} + +static inline void phy_destroy(struct phy *phy) +{ +} + +static inline void devm_phy_destroy(struct device *dev, struct phy *phy) +{ +} + +static inline 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)) +{ + return ERR_PTR(-ENOSYS); +} + +static inline 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)) +{ + return ERR_PTR(-ENOSYS); +} + +static inline void of_phy_provider_unregister(struct phy_provider *phy_provider) +{ +} + +static inline void devm_of_phy_provider_unregister(struct device *dev, + struct phy_provider *phy_provider) +{ +} +#endif + +static inline int phy_pm_runtime_get(struct phy *phy) +{ + if (WARN(IS_ERR(phy), "Invalid PHY reference\n")) + return -EINVAL; + + if (!pm_runtime_enabled(&phy->dev)) + return -ENOTSUPP; + + return pm_runtime_get(&phy->dev); +} + +static inline int phy_pm_runtime_get_sync(struct phy *phy) +{ + if (WARN(IS_ERR(phy), "Invalid PHY reference\n")) + return -EINVAL; + + if (!pm_runtime_enabled(&phy->dev)) + return -ENOTSUPP; + + return pm_runtime_get_sync(&phy->dev); +} + +static inline int phy_pm_runtime_put(struct phy *phy) +{ + if (WARN(IS_ERR(phy), "Invalid PHY reference\n")) + return -EINVAL; + + if (!pm_runtime_enabled(&phy->dev)) + return -ENOTSUPP; + + return pm_runtime_put(&phy->dev); +} + +static inline int phy_pm_runtime_put_sync(struct phy *phy) +{ + if (WARN(IS_ERR(phy), "Invalid PHY reference\n")) + return -EINVAL; + + if (!pm_runtime_enabled(&phy->dev)) + return -ENOTSUPP; + + return pm_runtime_put_sync(&phy->dev); +} + +static inline void phy_pm_runtime_allow(struct phy *phy) +{ + if (WARN(IS_ERR(phy), "Invalid PHY reference\n")) + return; + + if (!pm_runtime_enabled(&phy->dev)) + return; + + pm_runtime_allow(&phy->dev); +} + +static inline void phy_pm_runtime_forbid(struct phy *phy) +{ + if (WARN(IS_ERR(phy), "Invalid PHY reference\n")) + return; + + if (!pm_runtime_enabled(&phy->dev)) + return; + + pm_runtime_forbid(&phy->dev); +} + +static inline 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; +} + +static inline 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; +} + +static inline 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; +} + +static inline 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; +} + +#endif /* __DRIVERS_PHY_H */ -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html