diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig index a871a988829dbf..c9ad102a0fa94f 100644 --- a/drivers/usb/Kconfig +++ b/drivers/usb/Kconfig @@ -176,6 +176,8 @@ source "drivers/usb/gadget/Kconfig" source "drivers/usb/typec/Kconfig" +source "drivers/usb/repeater/Kconfig" + source "drivers/usb/roles/Kconfig" endif # USB_SUPPORT diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile index a81e6ef293af27..c96c66304edd1c 100644 --- a/drivers/usb/Makefile +++ b/drivers/usb/Makefile @@ -67,4 +67,6 @@ obj-$(CONFIG_USBIP_CORE) += usbip/ obj-$(CONFIG_TYPEC) += typec/ +obj-$(CONFIG_USB_REPEATER) += repeater/ + obj-$(CONFIG_USB_ROLE_SWITCH) += roles/ diff --git a/drivers/usb/repeater/Kconfig b/drivers/usb/repeater/Kconfig new file mode 100644 index 00000000000000..e12cd22c0adb98 --- /dev/null +++ b/drivers/usb/repeater/Kconfig @@ -0,0 +1,9 @@ +# SPDX-License-Identifier: GPL-2.0 + +config USB_REPEATER + tristate "USB Repeater Framework" + help + Enable this to allow the USB PHY drivers and the connected repeater + driver to bind together and to provide the USB driver ways to perform + set of operations with repeater for USB2 functionality using PHY and + controller driver. diff --git a/drivers/usb/repeater/Makefile b/drivers/usb/repeater/Makefile new file mode 100644 index 00000000000000..2d1b5f348976d7 --- /dev/null +++ b/drivers/usb/repeater/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for USB repeater drivers +# + +obj-$(CONFIG_USB_REPEATER) += repeater.o diff --git a/drivers/usb/repeater/repeater.c b/drivers/usb/repeater/repeater.c new file mode 100644 index 00000000000000..e97a95422735d4 --- /dev/null +++ b/drivers/usb/repeater/repeater.c @@ -0,0 +1,198 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2022, Qualcomm Innovation Center, Inc. All rights reserved. + * Copyright (c) 2022, Linaro Limited + */ + +#include +#include +#include +#include +#include + +#include + +static LIST_HEAD(usb_repeater_list); +static DEFINE_SPINLOCK(usb_repeater_lock); + +/** + * usb_put_repeater - release the USB repeater + * @rptr: the repeater returned by usb_get_repeater() + * + * Releases a refcount the caller received from usb_get_repeater(). + * + * For use by USB PHY drivers. + */ +void usb_put_repeater(struct usb_repeater *rptr) +{ + if (rptr) { + put_device(rptr->dev); + if (rptr->dev->driver && rptr->dev->driver->owner) { + struct module *owner = rptr->dev->driver->owner; + + module_put(owner); + } + } +} +EXPORT_SYMBOL_GPL(usb_put_repeater); + +static struct usb_repeater *of_usb_find_repeater(struct device_node *node) +{ + struct usb_repeater *rptr; + + if (!of_device_is_available(node)) + return ERR_PTR(-ENODEV); + + list_for_each_entry(rptr, &usb_repeater_list, head) { + if (node != rptr->dev->of_node) + continue; + + return rptr; + } + + return ERR_PTR(-EPROBE_DEFER); +} + +static void devm_usb_repeater_release(struct device *dev, void *res) +{ + struct usb_repeater *rptr = *(struct usb_repeater **)res; + + usb_put_repeater(rptr); +} + +/** + * devm_usb_get_repeater_by_node - find the USB repeater by device_node + * @dev: device that requests this USB repeater + * @node: the device_node for the USB repeater device. + * @nb: a notifier_block to register with the USB repeater. + * + * Returns the USB repeater driver associated with the given device_node, + * after getting a refcount to it, -ENODEV if there is no such repeater or + * -EPROBE_DEFER if the device is not yet loaded. While at that, it + * also associates the device with + * the repeater using devres. On driver detach, release function is invoked + * on the devres data, then, devres data is freed. + * + * For use by peripheral drivers for devices related to a repeater, + * such as a charger. + */ +struct usb_repeater *devm_usb_get_repeater_by_node(struct device *dev, + struct device_node *node, + struct notifier_block *nb) +{ + struct usb_repeater *rptr = ERR_PTR(-ENOMEM); + struct usb_repeater *rptr_devm; + unsigned long flags; + + rptr_devm = devres_alloc(devm_usb_repeater_release, + sizeof(*rptr_devm), GFP_KERNEL); + if (!rptr_devm) { + dev_dbg(dev, "failed to allocate memory for devres\n"); + goto err0; + } + + spin_lock_irqsave(&usb_repeater_lock, flags); + + rptr = of_usb_find_repeater(node); + if (IS_ERR(rptr)) { + devres_free(rptr_devm); + goto err0; + } + + if (!try_module_get(rptr->dev->driver->owner)) { + rptr = ERR_PTR(-ENODEV); + devres_free(rptr_devm); + goto err0; + } + devres_add(dev, rptr_devm); + + get_device(rptr->dev); +err0: + spin_unlock_irqrestore(&usb_repeater_lock, flags); + + return rptr; +} +EXPORT_SYMBOL_GPL(devm_usb_get_repeater_by_node); + +/** + * devm_usb_get_repeater_by_phandle - find the USB repeater by phandle + * @dev: device that requests this repeater + * @phandle: name of the property holding the repeater phandle value + * @index: the index of the repeater + * + * Returns the USB repeater driver associated with the given phandle value, + * after getting a refcount to it, -ENODEV if there is no such repeater or + * -EPROBE_DEFER if there is a phandle to the repeater, but the device is + * not yet loaded. While at that, it also associates the device with + * the repeater using devres. On driver detach, release function is invoked + * on the devres data, then, devres data is freed. + * + * For use by USB PHY drivers. + */ +struct usb_repeater *devm_usb_get_repeater_by_phandle(struct device *dev, + const char *phandle, u8 index) +{ + struct device_node *node; + struct usb_repeater *rptr; + + if (!dev->of_node) { + dev_dbg(dev, "device does not have a device node entry\n"); + return ERR_PTR(-EINVAL); + } + + node = of_parse_phandle(dev->of_node, phandle, index); + if (!node) { + dev_dbg(dev, "failed to get %s phandle in %pOF node\n", phandle, + dev->of_node); + return ERR_PTR(-ENODEV); + } + rptr = devm_usb_get_repeater_by_node(dev, node, NULL); + of_node_put(node); + return rptr; +} +EXPORT_SYMBOL_GPL(devm_usb_get_repeater_by_phandle); + +/** + * usb_add_repeater_dev - declare the USB repeater + * @rptr: the USB repeater to be used; or NULL + * + * This call is exclusively for use by repeater drivers to + * register the device to allow the USB phy driver to control it + * via repeater specific ops. + */ +int usb_add_repeater_dev(struct usb_repeater *rptr) +{ + unsigned long flags; + + if (!rptr->dev) { + dev_err(rptr->dev, "no device provided for repeater\n"); + return -EINVAL; + } + + spin_lock_irqsave(&usb_repeater_lock, flags); + list_add_tail(&rptr->head, &usb_repeater_list); + spin_unlock_irqrestore(&usb_repeater_lock, flags); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_add_repeater_dev); + +/** + * usb_remove_repeater - remove the USB repeater + * @rptr: the USB Repeater to be removed; + * + * This reverts the effects of usb_add_repeater_dev + */ +void usb_remove_repeater_dev(struct usb_repeater *rptr) +{ + unsigned long flags; + + spin_lock_irqsave(&usb_repeater_lock, flags); + if (rptr) + list_del(&rptr->head); + spin_unlock_irqrestore(&usb_repeater_lock, flags); +} +EXPORT_SYMBOL_GPL(usb_remove_repeater_dev); + +MODULE_DESCRIPTION("USB Repeater Framework"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/usb/repeater.h b/include/linux/usb/repeater.h new file mode 100644 index 00000000000000..e68e0936f1e50b --- /dev/null +++ b/include/linux/usb/repeater.h @@ -0,0 +1,78 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * USB Repeater defines + */ + +#ifndef __LINUX_USB_REPEATER_H +#define __LINUX_USB_REPEATER_H + +struct usb_repeater { + struct device *dev; + const char *label; + unsigned int flags; + + struct list_head head; + int (*reset)(struct usb_repeater *rptr, bool assert); + int (*init)(struct usb_repeater *rptr); + int (*power_on)(struct usb_repeater *rptr); + int (*power_off)(struct usb_repeater *rptr); +}; + +#if IS_ENABLED(CONFIG_USB_REPEATER) +extern struct usb_repeater *devm_usb_get_repeater_by_phandle(struct device *dev, + const char *phandle, u8 index); +extern struct usb_repeater *devm_usb_get_repeater_by_node(struct device *dev, + struct device_node *node, struct notifier_block *nb); +extern int usb_add_repeater_dev(struct usb_repeater *rptr); +extern void usb_remove_repeater_dev(struct usb_repeater *rptr); +#else +static inline struct usb_repeater *devm_usb_get_repeater_by_phandle(struct device *dev, + const char *phandle, u8 index) +{ + return ERR_PTR(-ENXIO); +} + +static inline struct usb_repeater *devm_usb_get_repeater_by_node(struct device *dev, + struct device_node *node, struct notifier_block *nb) +{ + return ERR_PTR(-ENXIO); +} + +static inline int usb_add_repeater_dev(struct usb_repeater *rptr) { return 0; } +static inline void usb_remove_repeater_dev(struct usb_repeater *rptr) { } + +#endif + +static inline int usb_repeater_reset(struct usb_repeater *rptr, bool assert) +{ + if (rptr && rptr->reset != NULL) + return rptr->reset(rptr, assert); + else + return 0; +} + +static inline int usb_repeater_init(struct usb_repeater *rptr) +{ + if (rptr && rptr->init != NULL) + return rptr->init(rptr); + else + return 0; +} + +static inline int usb_repeater_power_on(struct usb_repeater *rptr) +{ + if (rptr && rptr->power_on != NULL) + return rptr->power_on(rptr); + else + return 0; +} + +static inline int usb_repeater_power_off(struct usb_repeater *rptr) +{ + if (rptr && rptr->power_off != NULL) + return rptr->power_off(rptr); + else + return 0; +} + +#endif /* __LINUX_USB_REPEATER_H */