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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/misc/onboard_usb_hub.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/misc/onboard_usb_hub.c')
-rw-r--r--drivers/usb/misc/onboard_usb_hub.c461
1 files changed, 461 insertions, 0 deletions
diff --git a/drivers/usb/misc/onboard_usb_hub.c b/drivers/usb/misc/onboard_usb_hub.c
new file mode 100644
index 000000000..8edd0375e
--- /dev/null
+++ b/drivers/usb/misc/onboard_usb_hub.c
@@ -0,0 +1,461 @@
+// 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/gpio/consumer.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 void onboard_hub_attach_usb_driver(struct work_struct *work);
+
+static struct usb_device_driver onboard_hub_usbdev_driver;
+static DECLARE_WORK(attach_usb_driver_work, onboard_hub_attach_usb_driver);
+
+/************************** Platform driver **************************/
+
+struct usbdev_node {
+ struct usb_device *udev;
+ struct list_head list;
+};
+
+struct onboard_hub {
+ struct regulator *vdd;
+ struct device *dev;
+ const struct onboard_hub_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;
+};
+
+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;
+ }
+
+ fsleep(hub->pdata->reset_us);
+ gpiod_set_value_cansleep(hub->reset_gpio, 0);
+
+ hub->is_powered_on = true;
+
+ return 0;
+}
+
+static int onboard_hub_power_off(struct onboard_hub *hub)
+{
+ int err;
+
+ gpiod_set_value_cansleep(hub->reset_gpio, 1);
+
+ 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)
+{
+ const struct of_device_id *of_id;
+ struct device *dev = &pdev->dev;
+ struct onboard_hub *hub;
+ int err;
+
+ hub = devm_kzalloc(dev, sizeof(*hub), GFP_KERNEL);
+ if (!hub)
+ return -ENOMEM;
+
+ of_id = of_match_device(onboard_hub_match, &pdev->dev);
+ if (!of_id)
+ return -ENODEV;
+
+ hub->pdata = of_id->data;
+ if (!hub->pdata)
+ return -EINVAL;
+
+ hub->vdd = devm_regulator_get(dev, "vdd");
+ if (IS_ERR(hub->vdd))
+ return PTR_ERR(hub->vdd);
+
+ hub->reset_gpio = devm_gpiod_get_optional(dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(hub->reset_gpio))
+ return dev_err_probe(dev, PTR_ERR(hub->reset_gpio), "failed to get reset GPIO\n");
+
+ 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.
+ */
+ schedule_work(&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;
+
+ 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_GENESYS 0x05e3
+#define VENDOR_ID_MICROCHIP 0x0424
+#define VENDOR_ID_REALTEK 0x0bda
+#define VENDOR_ID_TI 0x0451
+
+/*
+ * 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_GENESYS, 0x0608) }, /* Genesys Logic GL850G USB 2.0 */
+ { USB_DEVICE(VENDOR_ID_GENESYS, 0x0610) }, /* Genesys Logic GL852G USB 2.0 */
+ { USB_DEVICE(VENDOR_ID_GENESYS, 0x0620) }, /* Genesys Logic GL3523 USB 3.1 */
+ { USB_DEVICE(VENDOR_ID_MICROCHIP, 0x2412) }, /* USB2412 USB 2.0 */
+ { USB_DEVICE(VENDOR_ID_MICROCHIP, 0x2514) }, /* USB2514B USB 2.0 */
+ { USB_DEVICE(VENDOR_ID_MICROCHIP, 0x2517) }, /* USB2517 USB 2.0 */
+ { 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 */
+ { USB_DEVICE(VENDOR_ID_TI, 0x8140) }, /* TI USB8041 3.0 */
+ { USB_DEVICE(VENDOR_ID_TI, 0x8142) }, /* TI USB8041 2.0 */
+ {}
+};
+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 = usb_register_device_driver(&onboard_hub_usbdev_driver, THIS_MODULE);
+ if (ret)
+ return ret;
+
+ ret = platform_driver_register(&onboard_hub_driver);
+ if (ret)
+ usb_deregister_device_driver(&onboard_hub_usbdev_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);
+
+ cancel_work_sync(&attach_usb_driver_work);
+}
+module_exit(onboard_hub_exit);
+
+MODULE_AUTHOR("Matthias Kaehlcke <mka@chromium.org>");
+MODULE_DESCRIPTION("Driver for discrete onboard USB hubs");
+MODULE_LICENSE("GPL v2");