diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-platform-onboard-usb-hub | 8 | ||||
| -rw-r--r-- | MAINTAINERS | 7 | ||||
| -rw-r--r-- | drivers/usb/core/Makefile | 4 | ||||
| -rw-r--r-- | drivers/usb/misc/Kconfig | 16 | ||||
| -rw-r--r-- | drivers/usb/misc/Makefile | 1 | ||||
| -rw-r--r-- | drivers/usb/misc/onboard_usb_hub.c | 428 | ||||
| -rw-r--r-- | drivers/usb/misc/onboard_usb_hub.h | 17 | ||||
| -rw-r--r-- | drivers/usb/misc/onboard_usb_hub_pdevs.c | 142 | ||||
| -rw-r--r-- | include/linux/usb/onboard_hub.h | 18 |
9 files changed, 641 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-platform-onboard-usb-hub b/Documentation/ABI/testing/sysfs-bus-platform-onboard-usb-hub new file mode 100644 index 000000000000..42deb0552065 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-platform-onboard-usb-hub @@ -0,0 +1,8 @@ +What: /sys/bus/platform/devices/<dev>/always_powered_in_suspend +Date: June 2022 +KernelVersion: 5.20 +Contact: Matthias Kaehlcke <matthias@kaehlcke.net> + linux-usb@vger.kernel.org +Description: + (RW) Controls whether the USB hub remains always powered + during system suspend or not.
\ No newline at end of file diff --git a/MAINTAINERS b/MAINTAINERS index 7533cb27adc0..f43b126eaf59 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14848,6 +14848,13 @@ S: Maintained T: git git://linuxtv.org/media_tree.git F: drivers/media/i2c/ov9734.c +ONBOARD USB HUB DRIVER +M: Matthias Kaehlcke <mka@chromium.org> +L: linux-usb@vger.kernel.org +S: Maintained +F: Documentation/ABI/testing/sysfs-bus-platform-onboard-usb-hub +F: drivers/usb/misc/onboard_usb_hub.c + ONENAND FLASH DRIVER M: Kyungmin Park <kyungmin.park@samsung.com> L: linux-mtd@lists.infradead.org diff --git a/drivers/usb/core/Makefile b/drivers/usb/core/Makefile index 18e874b0441e..7d338e9c0657 100644 --- a/drivers/usb/core/Makefile +++ b/drivers/usb/core/Makefile @@ -12,6 +12,10 @@ usbcore-$(CONFIG_OF) += of.o usbcore-$(CONFIG_USB_PCI) += hcd-pci.o usbcore-$(CONFIG_ACPI) += usb-acpi.o +ifdef CONFIG_USB_ONBOARD_HUB +usbcore-y += ../misc/onboard_usb_hub_pdevs.o +endif + obj-$(CONFIG_USB) += usbcore.o obj-$(CONFIG_USB_LEDS_TRIGGER_USBPORT) += ledtrig-usbport.o diff --git a/drivers/usb/misc/Kconfig b/drivers/usb/misc/Kconfig index 4c5ddbd75b7e..9367c12c7e6f 100644 --- a/drivers/usb/misc/Kconfig +++ b/drivers/usb/misc/Kconfig @@ -295,3 +295,19 @@ config BRCM_USB_PINMAP This option enables support for remapping some USB external signals, which are typically on dedicated pins on the chip, to any gpio. + +config USB_ONBOARD_HUB + tristate "Onboard USB hub support" + depends on OF || COMPILE_TEST + help + Say Y here if you want to support discrete onboard USB hubs that + don't require an additional control bus for initialization, but + need some non-trivial form of initialization, such as enabling a + power regulator. An example for such a hub is the Realtek + RTS5411. + + This driver can be used as a module but its state (module vs + builtin) must match the state of the USB subsystem. Enabling + this config will enable the driver and it will automatically + match the state of the USB subsystem. If this driver is a + module it will be called onboard_usb_hub. diff --git a/drivers/usb/misc/Makefile b/drivers/usb/misc/Makefile index 35bdb4b6c3b6..93581baec3a8 100644 --- a/drivers/usb/misc/Makefile +++ b/drivers/usb/misc/Makefile @@ -33,3 +33,4 @@ obj-$(CONFIG_USB_CHAOSKEY) += chaoskey.o obj-$(CONFIG_USB_SISUSBVGA) += sisusbvga/ obj-$(CONFIG_USB_LINK_LAYER_TEST) += lvstest.o obj-$(CONFIG_BRCM_USB_PINMAP) += brcmstb-usb-pinmap.o +obj-$(CONFIG_USB_ONBOARD_HUB) += onboard_usb_hub.o diff --git a/drivers/usb/misc/onboard_usb_hub.c b/drivers/usb/misc/onboard_usb_hub.c new file mode 100644 index 000000000000..6b9b949d17d3 --- /dev/null +++ b/drivers/usb/misc/onboard_usb_hub.c @@ -0,0 +1,428 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for onboard USB hubs + * + * Copyright (c) 2022, Google LLC + */ + +#include <linux/device.h> +#include <linux/export.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/regulator/consumer.h> +#include <linux/slab.h> +#include <linux/suspend.h> +#include <linux/sysfs.h> +#include <linux/usb.h> +#include <linux/usb/hcd.h> +#include <linux/usb/onboard_hub.h> +#include <linux/workqueue.h> + +#include "onboard_usb_hub.h" + +static struct usb_device_driver onboard_hub_usbdev_driver; + +/************************** Platform driver **************************/ + +struct usbdev_node { + struct usb_device *udev; + struct list_head list; +}; + +struct onboard_hub { + struct regulator *vdd; + struct device *dev; + bool always_powered_in_suspend; + bool is_powered_on; + bool going_away; + struct list_head udev_list; + struct work_struct attach_usb_driver_work; + struct mutex lock; +}; + +static int onboard_hub_power_on(struct onboard_hub *hub) +{ + int err; + + err = regulator_enable(hub->vdd); + if (err) { + dev_err(hub->dev, "failed to enable regulator: %d\n", err); + return err; + } + + hub->is_powered_on = true; + + return 0; +} + +static int onboard_hub_power_off(struct onboard_hub *hub) +{ + int err; + + err = regulator_disable(hub->vdd); + if (err) { + dev_err(hub->dev, "failed to disable regulator: %d\n", err); + return err; + } + + hub->is_powered_on = false; + + return 0; +} + +static int __maybe_unused onboard_hub_suspend(struct device *dev) +{ + struct onboard_hub *hub = dev_get_drvdata(dev); + struct usbdev_node *node; + bool power_off = true; + + if (hub->always_powered_in_suspend) + return 0; + + mutex_lock(&hub->lock); + + list_for_each_entry(node, &hub->udev_list, list) { + if (!device_may_wakeup(node->udev->bus->controller)) + continue; + + if (usb_wakeup_enabled_descendants(node->udev)) { + power_off = false; + break; + } + } + + mutex_unlock(&hub->lock); + + if (!power_off) + return 0; + + return onboard_hub_power_off(hub); +} + +static int __maybe_unused onboard_hub_resume(struct device *dev) +{ + struct onboard_hub *hub = dev_get_drvdata(dev); + + if (hub->is_powered_on) + return 0; + + return onboard_hub_power_on(hub); +} + +static inline void get_udev_link_name(const struct usb_device *udev, char *buf, size_t size) +{ + snprintf(buf, size, "usb_dev.%s", dev_name(&udev->dev)); +} + +static int onboard_hub_add_usbdev(struct onboard_hub *hub, struct usb_device *udev) +{ + struct usbdev_node *node; + char link_name[64]; + int err; + + mutex_lock(&hub->lock); + + if (hub->going_away) { + err = -EINVAL; + goto error; + } + + node = kzalloc(sizeof(*node), GFP_KERNEL); + if (!node) { + err = -ENOMEM; + goto error; + } + + node->udev = udev; + + list_add(&node->list, &hub->udev_list); + + mutex_unlock(&hub->lock); + + get_udev_link_name(udev, link_name, sizeof(link_name)); + WARN_ON(sysfs_create_link(&hub->dev->kobj, &udev->dev.kobj, link_name)); + + return 0; + +error: + mutex_unlock(&hub->lock); + + return err; +} + +static void onboard_hub_remove_usbdev(struct onboard_hub *hub, const struct usb_device *udev) +{ + struct usbdev_node *node; + char link_name[64]; + + get_udev_link_name(udev, link_name, sizeof(link_name)); + sysfs_remove_link(&hub->dev->kobj, link_name); + + mutex_lock(&hub->lock); + + list_for_each_entry(node, &hub->udev_list, list) { + if (node->udev == udev) { + list_del(&node->list); + kfree(node); + break; + } + } + + mutex_unlock(&hub->lock); +} + +static ssize_t always_powered_in_suspend_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + const struct onboard_hub *hub = dev_get_drvdata(dev); + + return sysfs_emit(buf, "%d\n", hub->always_powered_in_suspend); +} + +static ssize_t always_powered_in_suspend_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct onboard_hub *hub = dev_get_drvdata(dev); + bool val; + int ret; + + ret = kstrtobool(buf, &val); + if (ret < 0) + return ret; + + hub->always_powered_in_suspend = val; + + return count; +} +static DEVICE_ATTR_RW(always_powered_in_suspend); + +static struct attribute *onboard_hub_attrs[] = { + &dev_attr_always_powered_in_suspend.attr, + NULL, +}; +ATTRIBUTE_GROUPS(onboard_hub); + +static void onboard_hub_attach_usb_driver(struct work_struct *work) +{ + int err; + + err = driver_attach(&onboard_hub_usbdev_driver.drvwrap.driver); + if (err) + pr_err("Failed to attach USB driver: %d\n", err); +} + +static int onboard_hub_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct onboard_hub *hub; + int err; + + hub = devm_kzalloc(dev, sizeof(*hub), GFP_KERNEL); + if (!hub) + return -ENOMEM; + + hub->vdd = devm_regulator_get(dev, "vdd"); + if (IS_ERR(hub->vdd)) + return PTR_ERR(hub->vdd); + + hub->dev = dev; + mutex_init(&hub->lock); + INIT_LIST_HEAD(&hub->udev_list); + + dev_set_drvdata(dev, hub); + + err = onboard_hub_power_on(hub); + if (err) + return err; + + /* + * The USB driver might have been detached from the USB devices by + * onboard_hub_remove() (e.g. through an 'unbind' by userspace), + * make sure to re-attach it if needed. + * + * This needs to be done deferred to avoid self-deadlocks on systems + * with nested onboard hubs. + */ + INIT_WORK(&hub->attach_usb_driver_work, onboard_hub_attach_usb_driver); + schedule_work(&hub->attach_usb_driver_work); + + return 0; +} + +static int onboard_hub_remove(struct platform_device *pdev) +{ + struct onboard_hub *hub = dev_get_drvdata(&pdev->dev); + struct usbdev_node *node; + struct usb_device *udev; + + hub->going_away = true; + + if (&hub->attach_usb_driver_work != current_work()) + cancel_work_sync(&hub->attach_usb_driver_work); + + mutex_lock(&hub->lock); + + /* unbind the USB devices to avoid dangling references to this device */ + while (!list_empty(&hub->udev_list)) { + node = list_first_entry(&hub->udev_list, struct usbdev_node, list); + udev = node->udev; + + /* + * Unbinding the driver will call onboard_hub_remove_usbdev(), + * which acquires hub->lock. We must release the lock first. + */ + get_device(&udev->dev); + mutex_unlock(&hub->lock); + device_release_driver(&udev->dev); + put_device(&udev->dev); + mutex_lock(&hub->lock); + } + + mutex_unlock(&hub->lock); + + return onboard_hub_power_off(hub); +} + +MODULE_DEVICE_TABLE(of, onboard_hub_match); + +static const struct dev_pm_ops __maybe_unused onboard_hub_pm_ops = { + SET_LATE_SYSTEM_SLEEP_PM_OPS(onboard_hub_suspend, onboard_hub_resume) +}; + +static struct platform_driver onboard_hub_driver = { + .probe = onboard_hub_probe, + .remove = onboard_hub_remove, + + .driver = { + .name = "onboard-usb-hub", + .of_match_table = onboard_hub_match, + .pm = pm_ptr(&onboard_hub_pm_ops), + .dev_groups = onboard_hub_groups, + }, +}; + +/************************** USB driver **************************/ + +#define VENDOR_ID_REALTEK 0x0bda + +/* + * Returns the onboard_hub platform device that is associated with the USB + * device passed as parameter. + */ +static struct onboard_hub *_find_onboard_hub(struct device *dev) +{ + struct platform_device *pdev; + struct device_node *np; + struct onboard_hub *hub; + + pdev = of_find_device_by_node(dev->of_node); + if (!pdev) { + np = of_parse_phandle(dev->of_node, "peer-hub", 0); + if (!np) { + dev_err(dev, "failed to find device node for peer hub\n"); + return ERR_PTR(-EINVAL); + } + + pdev = of_find_device_by_node(np); + of_node_put(np); + + if (!pdev) + return ERR_PTR(-ENODEV); + } + + hub = dev_get_drvdata(&pdev->dev); + put_device(&pdev->dev); + + /* + * The presence of drvdata ('hub') indicates that the platform driver + * finished probing. This handles the case where (conceivably) we could + * be running at the exact same time as the platform driver's probe. If + * we detect the race we request probe deferral and we'll come back and + * try again. + */ + if (!hub) + return ERR_PTR(-EPROBE_DEFER); + + return hub; +} + +static int onboard_hub_usbdev_probe(struct usb_device *udev) +{ + struct device *dev = &udev->dev; + struct onboard_hub *hub; + int err; + + /* ignore supported hubs without device tree node */ + if (!dev->of_node) + return -ENODEV; + + hub = _find_onboard_hub(dev); + if (IS_ERR(hub)) + return PTR_ERR(hub); + + dev_set_drvdata(dev, hub); + + err = onboard_hub_add_usbdev(hub, udev); + if (err) + return err; + + return 0; +} + +static void onboard_hub_usbdev_disconnect(struct usb_device *udev) +{ + struct onboard_hub *hub = dev_get_drvdata(&udev->dev); + + onboard_hub_remove_usbdev(hub, udev); +} + +static const struct usb_device_id onboard_hub_id_table[] = { + { USB_DEVICE(VENDOR_ID_REALTEK, 0x0411) }, /* RTS5411 USB 3.1 */ + { USB_DEVICE(VENDOR_ID_REALTEK, 0x5411) }, /* RTS5411 USB 2.1 */ + { USB_DEVICE(VENDOR_ID_REALTEK, 0x0414) }, /* RTS5414 USB 3.2 */ + { USB_DEVICE(VENDOR_ID_REALTEK, 0x5414) }, /* RTS5414 USB 2.1 */ + {} +}; +MODULE_DEVICE_TABLE(usb, onboard_hub_id_table); + +static struct usb_device_driver onboard_hub_usbdev_driver = { + .name = "onboard-usb-hub", + .probe = onboard_hub_usbdev_probe, + .disconnect = onboard_hub_usbdev_disconnect, + .generic_subclass = 1, + .supports_autosuspend = 1, + .id_table = onboard_hub_id_table, +}; + +static int __init onboard_hub_init(void) +{ + int ret; + + ret = platform_driver_register(&onboard_hub_driver); + if (ret) + return ret; + + ret = usb_register_device_driver(&onboard_hub_usbdev_driver, THIS_MODULE); + if (ret) + platform_driver_unregister(&onboard_hub_driver); + + return ret; +} +module_init(onboard_hub_init); + +static void __exit onboard_hub_exit(void) +{ + usb_deregister_device_driver(&onboard_hub_usbdev_driver); + platform_driver_unregister(&onboard_hub_driver); +} +module_exit(onboard_hub_exit); + +MODULE_AUTHOR("Matthias Kaehlcke <mka@chromium.org>"); +MODULE_DESCRIPTION("Driver for discrete onboard USB hubs"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/usb/misc/onboard_usb_hub.h b/drivers/usb/misc/onboard_usb_hub.h new file mode 100644 index 000000000000..d3a5b6938582 --- /dev/null +++ b/drivers/usb/misc/onboard_usb_hub.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (c) 2022, Google LLC + */ + +#ifndef _USB_MISC_ONBOARD_USB_HUB_H +#define _USB_MISC_ONBOARD_USB_HUB_H + +static const struct of_device_id onboard_hub_match[] = { + { .compatible = "usbbda,411" }, + { .compatible = "usbbda,5411" }, + { .compatible = "usbbda,414" }, + { .compatible = "usbbda,5414" }, + {} +}; + +#endif /* _USB_MISC_ONBOARD_USB_HUB_H */ diff --git a/drivers/usb/misc/onboard_usb_hub_pdevs.c b/drivers/usb/misc/onboard_usb_hub_pdevs.c new file mode 100644 index 000000000000..a0a5f719129f --- /dev/null +++ b/drivers/usb/misc/onboard_usb_hub_pdevs.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * API for creating and destroying USB onboard hub platform devices + * + * Copyright (c) 2022, Google LLC + */ + +#include <linux/device.h> +#include <linux/export.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/usb.h> +#include <linux/usb/hcd.h> +#include <linux/usb/of.h> + +#include "onboard_usb_hub.h" + +struct pdev_list_entry { + struct platform_device *pdev; + struct list_head node; +}; + +static bool of_is_onboard_usb_hub(const struct device_node *np) +{ + return !!of_match_node(onboard_hub_match, np); +} + +/** + * onboard_hub_create_pdevs -- create platform devices for onboard USB hubs + * @parent_hub : parent hub to scan for connected onboard hubs + * @pdev_list : list of onboard hub platform devices owned by the parent hub + * + * Creates a platform device for each supported onboard hub that is connected to + * the given parent hub. The platform device is in charge of initializing the + * hub (enable regulators, take the hub out of reset, ...) and can optionally + * control whether the hub remains powered during system suspend or not. + * + * To keep track of the platform devices they are added to a list that is owned + * by the parent hub. + * + * Some background about the logic in this function, which can be a bit hard + * to follow: + * + * Root hubs don't have dedicated device tree nodes, but use the node of their + * HCD. The primary and secondary HCD are usually represented by a single DT + * node. That means the root hubs of the primary and secondary HCD share the + * same device tree node (the HCD node). As a result this function can be called + * twice with the same DT node for root hubs. We only want to create a single + * platform device for each physical onboard hub, hence for root hubs the loop + * is only executed for the root hub of the primary HCD. Since the function + * scans through all child nodes it still creates pdevs for onboard hubs + * connected to the root hub of the secondary HCD if needed. + * + * Further there must be only one platform device for onboard hubs with a peer + * hub (the hub is a single physical device). To achieve this two measures are + * taken: pdevs for onboard hubs with a peer are only created when the function + * is called on behalf of the parent hub that is connected to the primary HCD + * (directly or through other hubs). For onboard hubs connected to root hubs + * the function processes the nodes of both peers. A platform device is only + * created if the peer hub doesn't have one already. + */ +void onboard_hub_create_pdevs(struct usb_device *parent_hub, struct list_head *pdev_list) +{ + int i; + struct usb_hcd *hcd = bus_to_hcd(parent_hub->bus); + struct device_node *np, *npc; + struct platform_device *pdev; + struct pdev_list_entry *pdle; + + if (!parent_hub->dev.of_node) + return; + + if (!parent_hub->parent && !usb_hcd_is_primary_hcd(hcd)) + return; + + for (i = 1; i <= parent_hub->maxchild; i++) { + np = usb_of_get_device_node(parent_hub, i); + if (!np) + continue; + + if (!of_is_onboard_usb_hub(np)) + goto node_put; + + npc = of_parse_phandle(np, "peer-hub", 0); + if (npc) { + if (!usb_hcd_is_primary_hcd(hcd)) { + of_node_put(npc); + goto node_put; + } + + pdev = of_find_device_by_node(npc); + of_node_put(npc); + + if (pdev) { + put_device(&pdev->dev); + goto node_put; + } + } + + pdev = of_platform_device_create(np, NULL, &parent_hub->dev); + if (!pdev) { + dev_err(&parent_hub->dev, + "failed to create platform device for onboard hub '%pOF'\n", np); + goto node_put; + } + + pdle = kzalloc(sizeof(*pdle), GFP_KERNEL); + if (!pdle) { + of_platform_device_destroy(&pdev->dev, NULL); + goto node_put; + } + + pdle->pdev = pdev; + list_add(&pdle->node, pdev_list); + +node_put: + of_node_put(np); + } +} +EXPORT_SYMBOL_GPL(onboard_hub_create_pdevs); + +/** + * onboard_hub_destroy_pdevs -- free resources of onboard hub platform devices + * @pdev_list : list of onboard hub platform devices + * + * Destroys the platform devices in the given list and frees the memory associated + * with the list entry. + */ +void onboard_hub_destroy_pdevs(struct list_head *pdev_list) +{ + struct pdev_list_entry *pdle, *tmp; + + list_for_each_entry_safe(pdle, tmp, pdev_list, node) { + list_del(&pdle->node); + of_platform_device_destroy(&pdle->pdev->dev, NULL); + kfree(pdle); + } +} +EXPORT_SYMBOL_GPL(onboard_hub_destroy_pdevs); diff --git a/include/linux/usb/onboard_hub.h b/include/linux/usb/onboard_hub.h new file mode 100644 index 000000000000..d9373230556e --- /dev/null +++ b/include/linux/usb/onboard_hub.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __LINUX_USB_ONBOARD_HUB_H +#define __LINUX_USB_ONBOARD_HUB_H + +struct usb_device; +struct list_head; + +#if IS_ENABLED(CONFIG_USB_ONBOARD_HUB) +void onboard_hub_create_pdevs(struct usb_device *parent_hub, struct list_head *pdev_list); +void onboard_hub_destroy_pdevs(struct list_head *pdev_list); +#else +static inline void onboard_hub_create_pdevs(struct usb_device *parent_hub, + struct list_head *pdev_list) {} +static inline void onboard_hub_destroy_pdevs(struct list_head *pdev_list) {} +#endif + +#endif /* __LINUX_USB_ONBOARD_HUB_H */ |