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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/usb/core/usb-acpi.c
Initial import
Diffstat (limited to 'drivers/usb/core/usb-acpi.c')
-rw-r--r--drivers/usb/core/usb-acpi.c228
1 files changed, 228 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..2776cfe64
--- /dev/null
+++ b/drivers/usb/core/usb-acpi.c
@@ -0,0 +1,228 @@
+/*
+ * USB-ACPI glue code
+ *
+ * Copyright 2012 Red Hat <mjg@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation, version 2.
+ *
+ */
+#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);
+
+/**
+ * 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;
+ acpi_status status;
+
+ /*
+ * According to ACPI Spec 9.13. 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);
+ 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_find_companion(struct device *dev)
+{
+ struct usb_device *udev;
+ struct acpi_device *adev;
+ acpi_handle *parent_handle;
+
+ /*
+ * In the ACPI DSDT table, only usb root hub and usb ports are
+ * acpi device nodes. The hierarchy like following.
+ * Device (EHC1)
+ * Device (HUBN)
+ * Device (PR01)
+ * Device (PR11)
+ * Device (PR12)
+ * Device (PR13)
+ * ...
+ * So all binding process is divided into two parts. binding
+ * root hub and usb ports.
+ */
+ if (is_usb_device(dev)) {
+ udev = to_usb_device(dev);
+ if (udev->parent)
+ return NULL;
+
+ /* root hub is only child (_ADR=0) under its parent, the HC */
+ adev = ACPI_COMPANION(dev->parent);
+ return acpi_find_child_device(adev, 0, false);
+ } else if (is_usb_port(dev)) {
+ struct usb_port *port_dev = to_usb_port(dev);
+ int port1 = port_dev->portnum;
+ struct acpi_pld_info *pld;
+ acpi_handle *handle;
+ acpi_status status;
+
+ /* Get the struct usb_device point of port's hub */
+ udev = to_usb_device(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) {
+ struct usb_hcd *hcd = bus_to_hcd(udev->bus);
+ int raw;
+
+ raw = usb_hcd_find_raw_port_number(hcd, port1);
+ adev = acpi_find_child_device(ACPI_COMPANION(&udev->dev),
+ raw, false);
+ if (!adev)
+ return NULL;
+ } else {
+ parent_handle =
+ usb_get_hub_port_acpi_handle(udev->parent,
+ udev->portnum);
+ if (!parent_handle)
+ return NULL;
+
+ acpi_bus_get_device(parent_handle, &adev);
+ adev = acpi_find_child_device(adev, port1, false);
+ if (!adev)
+ return NULL;
+ }
+ handle = adev->handle;
+ status = acpi_get_physical_device_location(handle, &pld);
+ if (ACPI_FAILURE(status) || !pld)
+ return adev;
+
+ 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;
+ }
+
+ 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);
+}