diff options
Diffstat (limited to 'drivers/usb/core/usb-acpi.c')
| -rw-r--r-- | drivers/usb/core/usb-acpi.c | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/drivers/usb/core/usb-acpi.c b/drivers/usb/core/usb-acpi.c new file mode 100644 index 000000000..533baa850 --- /dev/null +++ b/drivers/usb/core/usb-acpi.c @@ -0,0 +1,334 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * USB-ACPI glue code + * + * Copyright 2012 Red Hat <mjg@redhat.com> + */ +#include <linux/module.h> +#include <linux/usb.h> +#include <linux/device.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/acpi.h> +#include <linux/pci.h> +#include <linux/usb/hcd.h> + +#include "hub.h" + +/** + * usb_acpi_power_manageable - check whether usb port has + * acpi power resource. + * @hdev: USB device belonging to the usb hub + * @index: port index based zero + * + * Return true if the port has acpi power resource and false if no. + */ +bool usb_acpi_power_manageable(struct usb_device *hdev, int index) +{ + acpi_handle port_handle; + int port1 = index + 1; + + port_handle = usb_get_hub_port_acpi_handle(hdev, + port1); + if (port_handle) + return acpi_bus_power_manageable(port_handle); + else + return false; +} +EXPORT_SYMBOL_GPL(usb_acpi_power_manageable); + +#define UUID_USB_CONTROLLER_DSM "ce2ee385-00e6-48cb-9f05-2edb927c4899" +#define USB_DSM_DISABLE_U1_U2_FOR_PORT 5 + +/** + * usb_acpi_port_lpm_incapable - check if lpm should be disabled for a port. + * @hdev: USB device belonging to the usb hub + * @index: zero based port index + * + * Some USB3 ports may not support USB3 link power management U1/U2 states + * due to different retimer setup. ACPI provides _DSM method which returns 0x01 + * if U1 and U2 states should be disabled. Evaluate _DSM with: + * Arg0: UUID = ce2ee385-00e6-48cb-9f05-2edb927c4899 + * Arg1: Revision ID = 0 + * Arg2: Function Index = 5 + * Arg3: (empty) + * + * Return 1 if USB3 port is LPM incapable, negative on error, otherwise 0 + */ + +int usb_acpi_port_lpm_incapable(struct usb_device *hdev, int index) +{ + union acpi_object *obj; + acpi_handle port_handle; + int port1 = index + 1; + guid_t guid; + int ret; + + ret = guid_parse(UUID_USB_CONTROLLER_DSM, &guid); + if (ret) + return ret; + + port_handle = usb_get_hub_port_acpi_handle(hdev, port1); + if (!port_handle) { + dev_dbg(&hdev->dev, "port-%d no acpi handle\n", port1); + return -ENODEV; + } + + if (!acpi_check_dsm(port_handle, &guid, 0, + BIT(USB_DSM_DISABLE_U1_U2_FOR_PORT))) { + dev_dbg(&hdev->dev, "port-%d no _DSM function %d\n", + port1, USB_DSM_DISABLE_U1_U2_FOR_PORT); + return -ENODEV; + } + + obj = acpi_evaluate_dsm(port_handle, &guid, 0, + USB_DSM_DISABLE_U1_U2_FOR_PORT, NULL); + + if (!obj) + return -ENODEV; + + if (obj->type != ACPI_TYPE_INTEGER) { + dev_dbg(&hdev->dev, "evaluate port-%d _DSM failed\n", port1); + ACPI_FREE(obj); + return -EINVAL; + } + + if (obj->integer.value == 0x01) + ret = 1; + + ACPI_FREE(obj); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_acpi_port_lpm_incapable); + +/** + * usb_acpi_set_power_state - control usb port's power via acpi power + * resource + * @hdev: USB device belonging to the usb hub + * @index: port index based zero + * @enable: power state expected to be set + * + * Notice to use usb_acpi_power_manageable() to check whether the usb port + * has acpi power resource before invoking this function. + * + * Returns 0 on success, else negative errno. + */ +int usb_acpi_set_power_state(struct usb_device *hdev, int index, bool enable) +{ + struct usb_hub *hub = usb_hub_to_struct_hub(hdev); + struct usb_port *port_dev; + acpi_handle port_handle; + unsigned char state; + int port1 = index + 1; + int error = -EINVAL; + + if (!hub) + return -ENODEV; + port_dev = hub->ports[port1 - 1]; + + port_handle = (acpi_handle) usb_get_hub_port_acpi_handle(hdev, port1); + if (!port_handle) + return error; + + if (enable) + state = ACPI_STATE_D0; + else + state = ACPI_STATE_D3_COLD; + + error = acpi_bus_set_power(port_handle, state); + if (!error) + dev_dbg(&port_dev->dev, "acpi: power was set to %d\n", enable); + else + dev_dbg(&port_dev->dev, "acpi: power failed to be set\n"); + + return error; +} +EXPORT_SYMBOL_GPL(usb_acpi_set_power_state); + +static enum usb_port_connect_type usb_acpi_get_connect_type(acpi_handle handle, + struct acpi_pld_info *pld) +{ + enum usb_port_connect_type connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + union acpi_object *upc = NULL; + acpi_status status; + + /* + * According to 9.14 in ACPI Spec 6.2. _PLD indicates whether usb port + * is user visible and _UPC indicates whether it is connectable. If + * the port was visible and connectable, it could be freely connected + * and disconnected with USB devices. If no visible and connectable, + * a usb device is directly hard-wired to the port. If no visible and + * no connectable, the port would be not used. + */ + status = acpi_evaluate_object(handle, "_UPC", NULL, &buffer); + if (ACPI_FAILURE(status)) + goto out; + + upc = buffer.pointer; + if (!upc || (upc->type != ACPI_TYPE_PACKAGE) || upc->package.count != 4) + goto out; + + if (upc->package.elements[0].integer.value) + if (pld->user_visible) + connect_type = USB_PORT_CONNECT_TYPE_HOT_PLUG; + else + connect_type = USB_PORT_CONNECT_TYPE_HARD_WIRED; + else if (!pld->user_visible) + connect_type = USB_PORT_NOT_USED; +out: + kfree(upc); + return connect_type; +} + + +/* + * Private to usb-acpi, all the core needs to know is that + * port_dev->location is non-zero when it has been set by the firmware. + */ +#define USB_ACPI_LOCATION_VALID (1 << 31) + +static struct acpi_device * +usb_acpi_get_companion_for_port(struct usb_port *port_dev) +{ + struct usb_device *udev; + struct acpi_device *adev; + acpi_handle *parent_handle; + int port1; + + /* Get the struct usb_device point of port's hub */ + udev = to_usb_device(port_dev->dev.parent->parent); + + /* + * The root hub ports' parent is the root hub. The non-root-hub + * ports' parent is the parent hub port which the hub is + * connected to. + */ + if (!udev->parent) { + adev = ACPI_COMPANION(&udev->dev); + port1 = usb_hcd_find_raw_port_number(bus_to_hcd(udev->bus), + port_dev->portnum); + } else { + parent_handle = usb_get_hub_port_acpi_handle(udev->parent, + udev->portnum); + if (!parent_handle) + return NULL; + + adev = acpi_fetch_acpi_dev(parent_handle); + port1 = port_dev->portnum; + } + + return acpi_find_child_by_adr(adev, port1); +} + +static struct acpi_device * +usb_acpi_find_companion_for_port(struct usb_port *port_dev) +{ + struct acpi_device *adev; + struct acpi_pld_info *pld; + acpi_handle *handle; + acpi_status status; + + adev = usb_acpi_get_companion_for_port(port_dev); + if (!adev) + return NULL; + + handle = adev->handle; + status = acpi_get_physical_device_location(handle, &pld); + if (ACPI_SUCCESS(status) && pld) { + port_dev->location = USB_ACPI_LOCATION_VALID + | pld->group_token << 8 | pld->group_position; + port_dev->connect_type = usb_acpi_get_connect_type(handle, pld); + ACPI_FREE(pld); + } + + return adev; +} + +static struct acpi_device * +usb_acpi_find_companion_for_device(struct usb_device *udev) +{ + struct acpi_device *adev; + struct usb_port *port_dev; + struct usb_hub *hub; + + if (!udev->parent) { + /* + * root hub is only child (_ADR=0) under its parent, the HC. + * sysdev pointer is the HC as seen from firmware. + */ + adev = ACPI_COMPANION(udev->bus->sysdev); + return acpi_find_child_device(adev, 0, false); + } + + hub = usb_hub_to_struct_hub(udev->parent); + if (!hub) + return NULL; + + /* + * This is an embedded USB device connected to a port and such + * devices share port's ACPI companion. + */ + port_dev = hub->ports[udev->portnum - 1]; + return usb_acpi_get_companion_for_port(port_dev); +} + +static struct acpi_device *usb_acpi_find_companion(struct device *dev) +{ + /* + * The USB hierarchy like following: + * + * Device (EHC1) + * Device (HUBN) + * Device (PR01) + * Device (PR11) + * Device (PR12) + * Device (FN12) + * Device (FN13) + * Device (PR13) + * ... + * where HUBN is root hub, and PRNN are USB ports and devices + * connected to them, and FNNN are individualk functions for + * connected composite USB devices. PRNN and FNNN may contain + * _CRS and other methods describing sideband resources for + * the connected device. + * + * On the kernel side both root hub and embedded USB devices are + * represented as instances of usb_device structure, and ports + * are represented as usb_port structures, so the whole process + * is split into 2 parts: finding companions for devices and + * finding companions for ports. + * + * Note that we do not handle individual functions of composite + * devices yet, for that we would need to assign companions to + * devices corresponding to USB interfaces. + */ + if (is_usb_device(dev)) + return usb_acpi_find_companion_for_device(to_usb_device(dev)); + else if (is_usb_port(dev)) + return usb_acpi_find_companion_for_port(to_usb_port(dev)); + + return NULL; +} + +static bool usb_acpi_bus_match(struct device *dev) +{ + return is_usb_device(dev) || is_usb_port(dev); +} + +static struct acpi_bus_type usb_acpi_bus = { + .name = "USB", + .match = usb_acpi_bus_match, + .find_companion = usb_acpi_find_companion, +}; + +int usb_acpi_register(void) +{ + return register_acpi_bus_type(&usb_acpi_bus); +} + +void usb_acpi_unregister(void) +{ + unregister_acpi_bus_type(&usb_acpi_bus); +} |