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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/usb/roles
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/roles')
-rw-r--r--drivers/usb/roles/Kconfig27
-rw-r--r--drivers/usb/roles/Makefile3
-rw-r--r--drivers/usb/roles/class.c314
-rw-r--r--drivers/usb/roles/intel-xhci-usb-role-switch.c189
4 files changed, 533 insertions, 0 deletions
diff --git a/drivers/usb/roles/Kconfig b/drivers/usb/roles/Kconfig
new file mode 100644
index 000000000..e4194ac94
--- /dev/null
+++ b/drivers/usb/roles/Kconfig
@@ -0,0 +1,27 @@
+config USB_ROLE_SWITCH
+ tristate "USB Role Switch Support"
+ help
+ USB Role Switch is a device that can select the USB role - host or
+ device - for a USB port (connector). In most cases dual-role capable
+ USB controller will also represent the switch, but on some platforms
+ multiplexer/demultiplexer switch is used to route the data lines on
+ the USB connector between separate USB host and device controllers.
+
+ Say Y here if your USB connectors support both device and host roles.
+ To compile the driver as module, choose M here: the module will be
+ called roles.ko.
+
+if USB_ROLE_SWITCH
+
+config USB_ROLES_INTEL_XHCI
+ tristate "Intel XHCI USB Role Switch"
+ depends on ACPI && X86
+ help
+ Driver for the internal USB role switch for switching the USB data
+ lines between the xHCI host controller and the dwc3 gadget controller
+ found on various Intel SoCs.
+
+ To compile the driver as a module, choose M here: the module will
+ be called intel-xhci-usb-role-switch.
+
+endif # USB_ROLE_SWITCH
diff --git a/drivers/usb/roles/Makefile b/drivers/usb/roles/Makefile
new file mode 100644
index 000000000..c02873206
--- /dev/null
+++ b/drivers/usb/roles/Makefile
@@ -0,0 +1,3 @@
+obj-$(CONFIG_USB_ROLE_SWITCH) += roles.o
+roles-y := class.o
+obj-$(CONFIG_USB_ROLES_INTEL_XHCI) += intel-xhci-usb-role-switch.o
diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c
new file mode 100644
index 000000000..1dd492e89
--- /dev/null
+++ b/drivers/usb/roles/class.c
@@ -0,0 +1,314 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * USB Role Switch Support
+ *
+ * Copyright (C) 2018 Intel Corporation
+ * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
+ * Hans de Goede <hdegoede@redhat.com>
+ */
+
+#include <linux/usb/role.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+
+static struct class *role_class;
+
+struct usb_role_switch {
+ struct device dev;
+ struct mutex lock; /* device lock*/
+ enum usb_role role;
+
+ /* From descriptor */
+ struct device *usb2_port;
+ struct device *usb3_port;
+ struct device *udc;
+ usb_role_switch_set_t set;
+ usb_role_switch_get_t get;
+ bool allow_userspace_control;
+};
+
+#define to_role_switch(d) container_of(d, struct usb_role_switch, dev)
+
+/**
+ * usb_role_switch_set_role - Set USB role for a switch
+ * @sw: USB role switch
+ * @role: USB role to be switched to
+ *
+ * Set USB role @role for @sw.
+ */
+int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role)
+{
+ int ret;
+
+ if (IS_ERR_OR_NULL(sw))
+ return 0;
+
+ mutex_lock(&sw->lock);
+
+ ret = sw->set(sw->dev.parent, role);
+ if (!ret)
+ sw->role = role;
+
+ mutex_unlock(&sw->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(usb_role_switch_set_role);
+
+/**
+ * usb_role_switch_get_role - Get the USB role for a switch
+ * @sw: USB role switch
+ *
+ * Depending on the role-switch-driver this function returns either a cached
+ * value of the last set role, or reads back the actual value from the hardware.
+ */
+enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw)
+{
+ enum usb_role role;
+
+ if (IS_ERR_OR_NULL(sw))
+ return USB_ROLE_NONE;
+
+ mutex_lock(&sw->lock);
+
+ if (sw->get)
+ role = sw->get(sw->dev.parent);
+ else
+ role = sw->role;
+
+ mutex_unlock(&sw->lock);
+
+ return role;
+}
+EXPORT_SYMBOL_GPL(usb_role_switch_get_role);
+
+static int __switch_match(struct device *dev, const void *name)
+{
+ return !strcmp((const char *)name, dev_name(dev));
+}
+
+static void *usb_role_switch_match(struct device_connection *con, int ep,
+ void *data)
+{
+ struct device *dev;
+
+ dev = class_find_device(role_class, NULL, con->endpoint[ep],
+ __switch_match);
+
+ return dev ? to_role_switch(dev) : ERR_PTR(-EPROBE_DEFER);
+}
+
+/**
+ * usb_role_switch_get - Find USB role switch linked with the caller
+ * @dev: The caller device
+ *
+ * Finds and returns role switch linked with @dev. The reference count for the
+ * found switch is incremented.
+ */
+struct usb_role_switch *usb_role_switch_get(struct device *dev)
+{
+ struct usb_role_switch *sw;
+
+ sw = device_connection_find_match(dev, "usb-role-switch", NULL,
+ usb_role_switch_match);
+
+ if (!IS_ERR_OR_NULL(sw))
+ WARN_ON(!try_module_get(sw->dev.parent->driver->owner));
+
+ return sw;
+}
+EXPORT_SYMBOL_GPL(usb_role_switch_get);
+
+/**
+ * usb_role_switch_put - Release handle to a switch
+ * @sw: USB Role Switch
+ *
+ * Decrement reference count for @sw.
+ */
+void usb_role_switch_put(struct usb_role_switch *sw)
+{
+ if (!IS_ERR_OR_NULL(sw)) {
+ module_put(sw->dev.parent->driver->owner);
+ put_device(&sw->dev);
+ }
+}
+EXPORT_SYMBOL_GPL(usb_role_switch_put);
+
+static umode_t
+usb_role_switch_is_visible(struct kobject *kobj, struct attribute *attr, int n)
+{
+ struct device *dev = container_of(kobj, typeof(*dev), kobj);
+ struct usb_role_switch *sw = to_role_switch(dev);
+
+ if (sw->allow_userspace_control)
+ return attr->mode;
+
+ return 0;
+}
+
+static const char * const usb_roles[] = {
+ [USB_ROLE_NONE] = "none",
+ [USB_ROLE_HOST] = "host",
+ [USB_ROLE_DEVICE] = "device",
+};
+
+static ssize_t
+role_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct usb_role_switch *sw = to_role_switch(dev);
+ enum usb_role role = usb_role_switch_get_role(sw);
+
+ return sprintf(buf, "%s\n", usb_roles[role]);
+}
+
+static ssize_t role_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct usb_role_switch *sw = to_role_switch(dev);
+ int ret;
+
+ ret = sysfs_match_string(usb_roles, buf);
+ if (ret < 0) {
+ bool res;
+
+ /* Extra check if the user wants to disable the switch */
+ ret = kstrtobool(buf, &res);
+ if (ret || res)
+ return -EINVAL;
+ }
+
+ ret = usb_role_switch_set_role(sw, ret);
+ if (ret)
+ return ret;
+
+ return size;
+}
+static DEVICE_ATTR_RW(role);
+
+static struct attribute *usb_role_switch_attrs[] = {
+ &dev_attr_role.attr,
+ NULL,
+};
+
+static const struct attribute_group usb_role_switch_group = {
+ .is_visible = usb_role_switch_is_visible,
+ .attrs = usb_role_switch_attrs,
+};
+
+static const struct attribute_group *usb_role_switch_groups[] = {
+ &usb_role_switch_group,
+ NULL,
+};
+
+static int
+usb_role_switch_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ int ret;
+
+ ret = add_uevent_var(env, "USB_ROLE_SWITCH=%s", dev_name(dev));
+ if (ret)
+ dev_err(dev, "failed to add uevent USB_ROLE_SWITCH\n");
+
+ return ret;
+}
+
+static void usb_role_switch_release(struct device *dev)
+{
+ struct usb_role_switch *sw = to_role_switch(dev);
+
+ kfree(sw);
+}
+
+static const struct device_type usb_role_dev_type = {
+ .name = "usb_role_switch",
+ .groups = usb_role_switch_groups,
+ .uevent = usb_role_switch_uevent,
+ .release = usb_role_switch_release,
+};
+
+/**
+ * usb_role_switch_register - Register USB Role Switch
+ * @parent: Parent device for the switch
+ * @desc: Description of the switch
+ *
+ * USB Role Switch is a device capable or choosing the role for USB connector.
+ * On platforms where the USB controller is dual-role capable, the controller
+ * driver will need to register the switch. On platforms where the USB host and
+ * USB device controllers behind the connector are separate, there will be a
+ * mux, and the driver for that mux will need to register the switch.
+ *
+ * Returns handle to a new role switch or ERR_PTR. The content of @desc is
+ * copied.
+ */
+struct usb_role_switch *
+usb_role_switch_register(struct device *parent,
+ const struct usb_role_switch_desc *desc)
+{
+ struct usb_role_switch *sw;
+ int ret;
+
+ if (!desc || !desc->set)
+ return ERR_PTR(-EINVAL);
+
+ sw = kzalloc(sizeof(*sw), GFP_KERNEL);
+ if (!sw)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_init(&sw->lock);
+
+ sw->allow_userspace_control = desc->allow_userspace_control;
+ sw->usb2_port = desc->usb2_port;
+ sw->usb3_port = desc->usb3_port;
+ sw->udc = desc->udc;
+ sw->set = desc->set;
+ sw->get = desc->get;
+
+ sw->dev.parent = parent;
+ sw->dev.class = role_class;
+ sw->dev.type = &usb_role_dev_type;
+ dev_set_name(&sw->dev, "%s-role-switch", dev_name(parent));
+
+ ret = device_register(&sw->dev);
+ if (ret) {
+ put_device(&sw->dev);
+ return ERR_PTR(ret);
+ }
+
+ /* TODO: Symlinks for the host port and the device controller. */
+
+ return sw;
+}
+EXPORT_SYMBOL_GPL(usb_role_switch_register);
+
+/**
+ * usb_role_switch_unregister - Unregsiter USB Role Switch
+ * @sw: USB Role Switch
+ *
+ * Unregister switch that was registered with usb_role_switch_register().
+ */
+void usb_role_switch_unregister(struct usb_role_switch *sw)
+{
+ if (!IS_ERR_OR_NULL(sw))
+ device_unregister(&sw->dev);
+}
+EXPORT_SYMBOL_GPL(usb_role_switch_unregister);
+
+static int __init usb_roles_init(void)
+{
+ role_class = class_create(THIS_MODULE, "usb_role");
+ return PTR_ERR_OR_ZERO(role_class);
+}
+subsys_initcall(usb_roles_init);
+
+static void __exit usb_roles_exit(void)
+{
+ class_destroy(role_class);
+}
+module_exit(usb_roles_exit);
+
+MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
+MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("USB Role Class");
diff --git a/drivers/usb/roles/intel-xhci-usb-role-switch.c b/drivers/usb/roles/intel-xhci-usb-role-switch.c
new file mode 100644
index 000000000..277de9618
--- /dev/null
+++ b/drivers/usb/roles/intel-xhci-usb-role-switch.c
@@ -0,0 +1,189 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Intel XHCI (Cherry Trail, Broxton and others) USB OTG role switch driver
+ *
+ * Copyright (c) 2016-2017 Hans de Goede <hdegoede@redhat.com>
+ *
+ * Loosely based on android x86 kernel code which is:
+ *
+ * Copyright (C) 2014 Intel Corp.
+ *
+ * Author: Wu, Hao
+ */
+
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/usb/role.h>
+
+/* register definition */
+#define DUAL_ROLE_CFG0 0x68
+#define SW_VBUS_VALID BIT(24)
+#define SW_IDPIN_EN BIT(21)
+#define SW_IDPIN BIT(20)
+
+#define DUAL_ROLE_CFG1 0x6c
+#define HOST_MODE BIT(29)
+
+#define DUAL_ROLE_CFG1_POLL_TIMEOUT 1000
+
+#define DRV_NAME "intel_xhci_usb_sw"
+
+struct intel_xhci_usb_data {
+ struct usb_role_switch *role_sw;
+ void __iomem *base;
+};
+
+static int intel_xhci_usb_set_role(struct device *dev, enum usb_role role)
+{
+ struct intel_xhci_usb_data *data = dev_get_drvdata(dev);
+ unsigned long timeout;
+ acpi_status status;
+ u32 glk, val;
+
+ /*
+ * On many CHT devices ACPI event (_AEI) handlers read / modify /
+ * write the cfg0 register, just like we do. Take the ACPI lock
+ * to avoid us racing with the AML code.
+ */
+ status = acpi_acquire_global_lock(ACPI_WAIT_FOREVER, &glk);
+ if (ACPI_FAILURE(status) && status != AE_NOT_CONFIGURED) {
+ dev_err(dev, "Error could not acquire lock\n");
+ return -EIO;
+ }
+
+ pm_runtime_get_sync(dev);
+
+ /* Set idpin value as requested */
+ val = readl(data->base + DUAL_ROLE_CFG0);
+ switch (role) {
+ case USB_ROLE_NONE:
+ val |= SW_IDPIN;
+ val &= ~SW_VBUS_VALID;
+ break;
+ case USB_ROLE_HOST:
+ val &= ~SW_IDPIN;
+ val &= ~SW_VBUS_VALID;
+ break;
+ case USB_ROLE_DEVICE:
+ val |= SW_IDPIN;
+ val |= SW_VBUS_VALID;
+ break;
+ }
+ val |= SW_IDPIN_EN;
+
+ writel(val, data->base + DUAL_ROLE_CFG0);
+
+ acpi_release_global_lock(glk);
+
+ /* In most case it takes about 600ms to finish mode switching */
+ timeout = jiffies + msecs_to_jiffies(DUAL_ROLE_CFG1_POLL_TIMEOUT);
+
+ /* Polling on CFG1 register to confirm mode switch.*/
+ do {
+ val = readl(data->base + DUAL_ROLE_CFG1);
+ if (!!(val & HOST_MODE) == (role == USB_ROLE_HOST)) {
+ pm_runtime_put(dev);
+ return 0;
+ }
+
+ /* Interval for polling is set to about 5 - 10 ms */
+ usleep_range(5000, 10000);
+ } while (time_before(jiffies, timeout));
+
+ pm_runtime_put(dev);
+
+ dev_warn(dev, "Timeout waiting for role-switch\n");
+ return -ETIMEDOUT;
+}
+
+static enum usb_role intel_xhci_usb_get_role(struct device *dev)
+{
+ struct intel_xhci_usb_data *data = dev_get_drvdata(dev);
+ enum usb_role role;
+ u32 val;
+
+ pm_runtime_get_sync(dev);
+ val = readl(data->base + DUAL_ROLE_CFG0);
+ pm_runtime_put(dev);
+
+ if (!(val & SW_IDPIN))
+ role = USB_ROLE_HOST;
+ else if (val & SW_VBUS_VALID)
+ role = USB_ROLE_DEVICE;
+ else
+ role = USB_ROLE_NONE;
+
+ return role;
+}
+
+static const struct usb_role_switch_desc sw_desc = {
+ .set = intel_xhci_usb_set_role,
+ .get = intel_xhci_usb_get_role,
+ .allow_userspace_control = true,
+};
+
+static int intel_xhci_usb_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct intel_xhci_usb_data *data;
+ struct resource *res;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
+ data->base = devm_ioremap_nocache(dev, res->start, resource_size(res));
+ if (!data->base)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, data);
+
+ data->role_sw = usb_role_switch_register(dev, &sw_desc);
+ if (IS_ERR(data->role_sw))
+ return PTR_ERR(data->role_sw);
+
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+
+ return 0;
+}
+
+static int intel_xhci_usb_remove(struct platform_device *pdev)
+{
+ struct intel_xhci_usb_data *data = platform_get_drvdata(pdev);
+
+ pm_runtime_disable(&pdev->dev);
+
+ usb_role_switch_unregister(data->role_sw);
+ return 0;
+}
+
+static const struct platform_device_id intel_xhci_usb_table[] = {
+ { .name = DRV_NAME },
+ {}
+};
+MODULE_DEVICE_TABLE(platform, intel_xhci_usb_table);
+
+static struct platform_driver intel_xhci_usb_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ },
+ .id_table = intel_xhci_usb_table,
+ .probe = intel_xhci_usb_probe,
+ .remove = intel_xhci_usb_remove,
+};
+
+module_platform_driver(intel_xhci_usb_driver);
+
+MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
+MODULE_DESCRIPTION("Intel XHCI USB role switch driver");
+MODULE_LICENSE("GPL");