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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/core/usb-acpi.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.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/core/usb-acpi.c')
-rw-r--r--drivers/usb/core/usb-acpi.c334
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);
+}