// SPDX-License-Identifier: GPL-2.0-only /* * Driver for onboard USB devices * * Copyright (c) 2022, Google LLC */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "onboard_usb_dev.h" /* USB5744 register offset and mask */ #define USB5744_CMD_ATTACH 0xAA #define USB5744_CMD_ATTACH_LSB 0x56 #define USB5744_CMD_CREG_ACCESS 0x99 #define USB5744_CMD_CREG_ACCESS_LSB 0x37 #define USB5744_CREG_MEM_ADDR 0x00 #define USB5744_CREG_WRITE 0x00 #define USB5744_CREG_RUNTIMEFLAGS2 0x41 #define USB5744_CREG_RUNTIMEFLAGS2_LSB 0x1D #define USB5744_CREG_BYPASS_UDC_SUSPEND BIT(3) static void onboard_dev_attach_usb_driver(struct work_struct *work); static struct usb_device_driver onboard_dev_usbdev_driver; static DECLARE_WORK(attach_usb_driver_work, onboard_dev_attach_usb_driver); /************************** Platform driver **************************/ struct usbdev_node { struct usb_device *udev; struct list_head list; }; struct onboard_dev { struct regulator_bulk_data supplies[MAX_SUPPLIES]; struct device *dev; const struct onboard_dev_pdata *pdata; struct gpio_desc *reset_gpio; bool always_powered_in_suspend; bool is_powered_on; bool going_away; struct list_head udev_list; struct mutex lock; struct clk *clk; }; static int onboard_dev_get_regulators(struct onboard_dev *onboard_dev) { const char * const *supply_names = onboard_dev->pdata->supply_names; unsigned int num_supplies = onboard_dev->pdata->num_supplies; struct device *dev = onboard_dev->dev; unsigned int i; int err; if (num_supplies > MAX_SUPPLIES) return dev_err_probe(dev, -EINVAL, "max %d supplies supported!\n", MAX_SUPPLIES); for (i = 0; i < num_supplies; i++) onboard_dev->supplies[i].supply = supply_names[i]; err = devm_regulator_bulk_get(dev, num_supplies, onboard_dev->supplies); if (err) dev_err(dev, "Failed to get regulator supplies: %pe\n", ERR_PTR(err)); return err; } static int onboard_dev_power_on(struct onboard_dev *onboard_dev) { int err; err = clk_prepare_enable(onboard_dev->clk); if (err) { dev_err(onboard_dev->dev, "failed to enable clock: %pe\n", ERR_PTR(err)); return err; } err = regulator_bulk_enable(onboard_dev->pdata->num_supplies, onboard_dev->supplies); if (err) { dev_err(onboard_dev->dev, "failed to enable supplies: %pe\n", ERR_PTR(err)); goto disable_clk; } fsleep(onboard_dev->pdata->reset_us); gpiod_set_value_cansleep(onboard_dev->reset_gpio, 0); fsleep(onboard_dev->pdata->power_on_delay_us); onboard_dev->is_powered_on = true; return 0; disable_clk: clk_disable_unprepare(onboard_dev->clk); return err; } static int onboard_dev_power_off(struct onboard_dev *onboard_dev) { int err; gpiod_set_value_cansleep(onboard_dev->reset_gpio, 1); err = regulator_bulk_disable(onboard_dev->pdata->num_supplies, onboard_dev->supplies); if (err) { dev_err(onboard_dev->dev, "failed to disable supplies: %pe\n", ERR_PTR(err)); return err; } clk_disable_unprepare(onboard_dev->clk); onboard_dev->is_powered_on = false; return 0; } static int __maybe_unused onboard_dev_suspend(struct device *dev) { struct onboard_dev *onboard_dev = dev_get_drvdata(dev); struct usbdev_node *node; bool power_off = true; if (onboard_dev->always_powered_in_suspend) return 0; mutex_lock(&onboard_dev->lock); list_for_each_entry(node, &onboard_dev->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(&onboard_dev->lock); if (!power_off) return 0; return onboard_dev_power_off(onboard_dev); } static int __maybe_unused onboard_dev_resume(struct device *dev) { struct onboard_dev *onboard_dev = dev_get_drvdata(dev); if (onboard_dev->is_powered_on) return 0; return onboard_dev_power_on(onboard_dev); } 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_dev_add_usbdev(struct onboard_dev *onboard_dev, struct usb_device *udev) { struct usbdev_node *node; char link_name[64]; int err; mutex_lock(&onboard_dev->lock); if (onboard_dev->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, &onboard_dev->udev_list); mutex_unlock(&onboard_dev->lock); get_udev_link_name(udev, link_name, sizeof(link_name)); WARN_ON(sysfs_create_link(&onboard_dev->dev->kobj, &udev->dev.kobj, link_name)); return 0; error: mutex_unlock(&onboard_dev->lock); return err; } static void onboard_dev_remove_usbdev(struct onboard_dev *onboard_dev, 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(&onboard_dev->dev->kobj, link_name); mutex_lock(&onboard_dev->lock); list_for_each_entry(node, &onboard_dev->udev_list, list) { if (node->udev == udev) { list_del(&node->list); kfree(node); break; } } mutex_unlock(&onboard_dev->lock); } static ssize_t always_powered_in_suspend_show(struct device *dev, struct device_attribute *attr, char *buf) { const struct onboard_dev *onboard_dev = dev_get_drvdata(dev); return sysfs_emit(buf, "%d\n", onboard_dev->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_dev *onboard_dev = dev_get_drvdata(dev); bool val; int ret; ret = kstrtobool(buf, &val); if (ret < 0) return ret; onboard_dev->always_powered_in_suspend = val; return count; } static DEVICE_ATTR_RW(always_powered_in_suspend); static struct attribute *onboard_dev_attrs[] = { &dev_attr_always_powered_in_suspend.attr, NULL, }; static umode_t onboard_dev_attrs_are_visible(struct kobject *kobj, struct attribute *attr, int n) { struct device *dev = kobj_to_dev(kobj); struct onboard_dev *onboard_dev = dev_get_drvdata(dev); if (attr == &dev_attr_always_powered_in_suspend.attr && !onboard_dev->pdata->is_hub) return 0; return attr->mode; } static const struct attribute_group onboard_dev_group = { .is_visible = onboard_dev_attrs_are_visible, .attrs = onboard_dev_attrs, }; __ATTRIBUTE_GROUPS(onboard_dev); static void onboard_dev_attach_usb_driver(struct work_struct *work) { int err; err = driver_attach(&onboard_dev_usbdev_driver.driver); if (err) pr_err("Failed to attach USB driver: %pe\n", ERR_PTR(err)); } static int onboard_dev_5744_i2c_init(struct i2c_client *client) { #if IS_ENABLED(CONFIG_USB_ONBOARD_DEV_USB5744) struct device *dev = &client->dev; int ret; /* * Set BYPASS_UDC_SUSPEND bit to ensure MCU is always enabled * and ready to respond to SMBus runtime commands. * The command writes 5 bytes to memory and single data byte in * configuration register. */ char wr_buf[7] = {USB5744_CREG_MEM_ADDR, 5, USB5744_CREG_WRITE, 1, USB5744_CREG_RUNTIMEFLAGS2, USB5744_CREG_RUNTIMEFLAGS2_LSB, USB5744_CREG_BYPASS_UDC_SUSPEND}; ret = i2c_smbus_write_block_data(client, 0, sizeof(wr_buf), wr_buf); if (ret) return dev_err_probe(dev, ret, "BYPASS_UDC_SUSPEND bit configuration failed\n"); ret = i2c_smbus_write_word_data(client, USB5744_CMD_CREG_ACCESS, USB5744_CMD_CREG_ACCESS_LSB); if (ret) return dev_err_probe(dev, ret, "Configuration Register Access Command failed\n"); /* Send SMBus command to boot hub. */ ret = i2c_smbus_write_word_data(client, USB5744_CMD_ATTACH, USB5744_CMD_ATTACH_LSB); if (ret < 0) return dev_err_probe(dev, ret, "USB Attach with SMBus command failed\n"); return ret; #else return -ENODEV; #endif } static int onboard_dev_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct onboard_dev *onboard_dev; struct device_node *i2c_node; int err; onboard_dev = devm_kzalloc(dev, sizeof(*onboard_dev), GFP_KERNEL); if (!onboard_dev) return -ENOMEM; onboard_dev->pdata = device_get_match_data(dev); if (!onboard_dev->pdata) return -EINVAL; if (!onboard_dev->pdata->is_hub) onboard_dev->always_powered_in_suspend = true; onboard_dev->dev = dev; err = onboard_dev_get_regulators(onboard_dev); if (err) return err; onboard_dev->clk = devm_clk_get_optional(dev, NULL); if (IS_ERR(onboard_dev->clk)) return dev_err_probe(dev, PTR_ERR(onboard_dev->clk), "failed to get clock\n"); onboard_dev->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); if (IS_ERR(onboard_dev->reset_gpio)) return dev_err_probe(dev, PTR_ERR(onboard_dev->reset_gpio), "failed to get reset GPIO\n"); mutex_init(&onboard_dev->lock); INIT_LIST_HEAD(&onboard_dev->udev_list); dev_set_drvdata(dev, onboard_dev); err = onboard_dev_power_on(onboard_dev); if (err) return err; i2c_node = of_parse_phandle(pdev->dev.of_node, "i2c-bus", 0); if (i2c_node) { struct i2c_client *client = NULL; #if IS_ENABLED(CONFIG_USB_ONBOARD_DEV_USB5744) client = of_find_i2c_device_by_node(i2c_node); #endif of_node_put(i2c_node); if (!client) { err = -EPROBE_DEFER; goto err_power_off; } if (of_device_is_compatible(pdev->dev.of_node, "usb424,2744") || of_device_is_compatible(pdev->dev.of_node, "usb424,5744")) err = onboard_dev_5744_i2c_init(client); put_device(&client->dev); if (err < 0) goto err_power_off; } /* * The USB driver might have been detached from the USB devices by * onboard_dev_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. */ schedule_work(&attach_usb_driver_work); return 0; err_power_off: onboard_dev_power_off(onboard_dev); return err; } static void onboard_dev_remove(struct platform_device *pdev) { struct onboard_dev *onboard_dev = dev_get_drvdata(&pdev->dev); struct usbdev_node *node; struct usb_device *udev; onboard_dev->going_away = true; mutex_lock(&onboard_dev->lock); /* unbind the USB devices to avoid dangling references to this device */ while (!list_empty(&onboard_dev->udev_list)) { node = list_first_entry(&onboard_dev->udev_list, struct usbdev_node, list); udev = node->udev; /* * Unbinding the driver will call onboard_dev_remove_usbdev(), * which acquires onboard_dev->lock. We must release the lock * first. */ get_device(&udev->dev); mutex_unlock(&onboard_dev->lock); device_release_driver(&udev->dev); put_device(&udev->dev); mutex_lock(&onboard_dev->lock); } mutex_unlock(&onboard_dev->lock); onboard_dev_power_off(onboard_dev); } MODULE_DEVICE_TABLE(of, onboard_dev_match); static const struct dev_pm_ops __maybe_unused onboard_dev_pm_ops = { SET_LATE_SYSTEM_SLEEP_PM_OPS(onboard_dev_suspend, onboard_dev_resume) }; static struct platform_driver onboard_dev_driver = { .probe = onboard_dev_probe, .remove = onboard_dev_remove, .driver = { .name = "onboard-usb-dev", .of_match_table = onboard_dev_match, .pm = pm_ptr(&onboard_dev_pm_ops), .dev_groups = onboard_dev_groups, }, }; /************************** USB driver **************************/ #define VENDOR_ID_CYPRESS 0x04b4 #define VENDOR_ID_GENESYS 0x05e3 #define VENDOR_ID_MICROCHIP 0x0424 #define VENDOR_ID_REALTEK 0x0bda #define VENDOR_ID_TI 0x0451 #define VENDOR_ID_VIA 0x2109 #define VENDOR_ID_XMOS 0x20B1 /* * Returns the onboard_dev platform device that is associated with the USB * device passed as parameter. */ static struct onboard_dev *_find_onboard_dev(struct device *dev) { struct platform_device *pdev; struct device_node *np; struct onboard_dev *onboard_dev; 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); } onboard_dev = dev_get_drvdata(&pdev->dev); put_device(&pdev->dev); /* * The presence of drvdata 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 (!onboard_dev) return ERR_PTR(-EPROBE_DEFER); return onboard_dev; } static bool onboard_dev_usbdev_match(struct usb_device *udev) { /* Onboard devices using this driver must have a device tree node */ return !!udev->dev.of_node; } static int onboard_dev_usbdev_probe(struct usb_device *udev) { struct device *dev = &udev->dev; struct onboard_dev *onboard_dev; int err; onboard_dev = _find_onboard_dev(dev); if (IS_ERR(onboard_dev)) return PTR_ERR(onboard_dev); dev_set_drvdata(dev, onboard_dev); err = onboard_dev_add_usbdev(onboard_dev, udev); if (err) return err; return 0; } static void onboard_dev_usbdev_disconnect(struct usb_device *udev) { struct onboard_dev *onboard_dev = dev_get_drvdata(&udev->dev); onboard_dev_remove_usbdev(onboard_dev, udev); } static const struct usb_device_id onboard_dev_id_table[] = { { USB_DEVICE(VENDOR_ID_CYPRESS, 0x6504) }, /* CYUSB33{0,1,2}x/CYUSB230x 3.0 HUB */ { USB_DEVICE(VENDOR_ID_CYPRESS, 0x6506) }, /* CYUSB33{0,1,2}x/CYUSB230x 2.0 HUB */ { USB_DEVICE(VENDOR_ID_CYPRESS, 0x6570) }, /* CY7C6563x 2.0 HUB */ { USB_DEVICE(VENDOR_ID_GENESYS, 0x0608) }, /* Genesys Logic GL850G USB 2.0 HUB */ { USB_DEVICE(VENDOR_ID_GENESYS, 0x0610) }, /* Genesys Logic GL852G USB 2.0 HUB */ { USB_DEVICE(VENDOR_ID_GENESYS, 0x0620) }, /* Genesys Logic GL3523 USB 3.1 HUB */ { USB_DEVICE(VENDOR_ID_MICROCHIP, 0x2412) }, /* USB2412 USB 2.0 HUB */ { USB_DEVICE(VENDOR_ID_MICROCHIP, 0x2514) }, /* USB2514B USB 2.0 HUB */ { USB_DEVICE(VENDOR_ID_MICROCHIP, 0x2517) }, /* USB2517 USB 2.0 HUB */ { USB_DEVICE(VENDOR_ID_MICROCHIP, 0x2744) }, /* USB5744 USB 2.0 HUB */ { USB_DEVICE(VENDOR_ID_MICROCHIP, 0x5744) }, /* USB5744 USB 3.0 HUB */ { USB_DEVICE(VENDOR_ID_REALTEK, 0x0411) }, /* RTS5411 USB 3.1 HUB */ { USB_DEVICE(VENDOR_ID_REALTEK, 0x5411) }, /* RTS5411 USB 2.1 HUB */ { USB_DEVICE(VENDOR_ID_REALTEK, 0x0414) }, /* RTS5414 USB 3.2 HUB */ { USB_DEVICE(VENDOR_ID_REALTEK, 0x5414) }, /* RTS5414 USB 2.1 HUB */ { USB_DEVICE(VENDOR_ID_TI, 0x8025) }, /* TI USB8020B 3.0 HUB */ { USB_DEVICE(VENDOR_ID_TI, 0x8027) }, /* TI USB8020B 2.0 HUB */ { USB_DEVICE(VENDOR_ID_TI, 0x8140) }, /* TI USB8041 3.0 HUB */ { USB_DEVICE(VENDOR_ID_TI, 0x8142) }, /* TI USB8041 2.0 HUB */ { USB_DEVICE(VENDOR_ID_VIA, 0x0817) }, /* VIA VL817 3.1 HUB */ { USB_DEVICE(VENDOR_ID_VIA, 0x2817) }, /* VIA VL817 2.0 HUB */ { USB_DEVICE(VENDOR_ID_XMOS, 0x0013) }, /* XMOS XVF3500 Voice Processor */ {} }; MODULE_DEVICE_TABLE(usb, onboard_dev_id_table); static struct usb_device_driver onboard_dev_usbdev_driver = { .name = "onboard-usb-dev", .match = onboard_dev_usbdev_match, .probe = onboard_dev_usbdev_probe, .disconnect = onboard_dev_usbdev_disconnect, .generic_subclass = 1, .supports_autosuspend = 1, .id_table = onboard_dev_id_table, }; static int __init onboard_dev_init(void) { int ret; ret = usb_register_device_driver(&onboard_dev_usbdev_driver, THIS_MODULE); if (ret) return ret; ret = platform_driver_register(&onboard_dev_driver); if (ret) usb_deregister_device_driver(&onboard_dev_usbdev_driver); return ret; } module_init(onboard_dev_init); static void __exit onboard_dev_exit(void) { usb_deregister_device_driver(&onboard_dev_usbdev_driver); platform_driver_unregister(&onboard_dev_driver); cancel_work_sync(&attach_usb_driver_work); } module_exit(onboard_dev_exit); MODULE_AUTHOR("Matthias Kaehlcke "); MODULE_DESCRIPTION("Driver for discrete onboard USB devices"); MODULE_LICENSE("GPL v2");