Files
android_kernel_samsung_sm8750/drivers/pci/hotplug/acpiphp.h
Rafael J. Wysocki 3c2cc7ff9e ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug
The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its
hotplug context objects directly to ACPI namespace nodes representing
hotplug devices.  However, after recent changes causing struct
acpi_device to be created for every namespace node representing a
device (regardless of its status), that is not necessary any more.
Moreover, it's vulnerable to the theoretical issue that the ACPI
handle passed in the context between handle_hotplug_event() and
hotplug_event_work() may become invalid in the meantime (as a
result of a concurrent table unload).

In principle, this issue might be addressed by adding a non-empty
release handler for ACPIPHP hotplug context objects analogous to
acpi_scan_drop_device(), but that would duplicate the code in that
function and in acpi_device_del_work_fn().  For this reason, it's
better to modify ACPIPHP to attach its device hotplug contexts to
struct device objects representing hotplug devices and make it
use acpi_hotplug_notify_cb() as its notify handler.  At the same
time, acpi_device_hotplug() can be modified to dispatch the new
.hp.event() callback pointing to acpiphp_hotplug_event() from ACPI
device objects associated with PCI devices or use the generic
ACPI device hotplug code for device objects with matching scan
handlers.

This allows the existing code duplication between ACPIPHP and the
ACPI core to be reduced too and makes further ACPI-based device
hotplug consolidation possible.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00

194 lines
5.1 KiB
C

/*
* ACPI PCI Hot Plug Controller Driver
*
* Copyright (C) 1995,2001 Compaq Computer Corporation
* Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
* Copyright (C) 2001 IBM Corp.
* Copyright (C) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com)
* Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com)
* Copyright (C) 2002,2003 NEC Corporation
* Copyright (C) 2003-2005 Matthew Wilcox (matthew.wilcox@hp.com)
* Copyright (C) 2003-2005 Hewlett Packard
*
* All rights reserved.
*
* 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; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Send feedback to <gregkh@us.ibm.com>,
* <t-kochi@bq.jp.nec.com>
*
*/
#ifndef _ACPIPHP_H
#define _ACPIPHP_H
#include <linux/acpi.h>
#include <linux/mutex.h>
#include <linux/pci_hotplug.h>
struct acpiphp_context;
struct acpiphp_bridge;
struct acpiphp_slot;
/*
* struct slot - slot information for each *physical* slot
*/
struct slot {
struct hotplug_slot *hotplug_slot;
struct acpiphp_slot *acpi_slot;
struct hotplug_slot_info info;
unsigned int sun; /* ACPI _SUN (Slot User Number) value */
};
static inline const char *slot_name(struct slot *slot)
{
return hotplug_slot_name(slot->hotplug_slot);
}
/*
* struct acpiphp_bridge - PCI bridge information
*
* for each bridge device in ACPI namespace
*/
struct acpiphp_bridge {
struct list_head list;
struct list_head slots;
struct kref ref;
struct acpiphp_context *context;
int nr_slots;
/* This bus (host bridge) or Secondary bus (PCI-to-PCI bridge) */
struct pci_bus *pci_bus;
/* PCI-to-PCI bridge device */
struct pci_dev *pci_dev;
bool is_going_away;
};
/*
* struct acpiphp_slot - PCI slot information
*
* PCI slot information for each *physical* PCI slot
*/
struct acpiphp_slot {
struct list_head node;
struct pci_bus *bus;
struct list_head funcs; /* one slot may have different
objects (i.e. for each function) */
struct slot *slot;
u8 device; /* pci device# */
u32 flags; /* see below */
};
/*
* struct acpiphp_func - PCI function information
*
* PCI function information for each object in ACPI namespace
* typically 8 objects per slot (i.e. for each PCI function)
*/
struct acpiphp_func {
struct acpiphp_bridge *parent;
struct acpiphp_slot *slot;
struct list_head sibling;
u8 function; /* pci function# */
u32 flags; /* see below */
};
struct acpiphp_context {
struct acpi_hotplug_context hp;
struct acpiphp_func func;
struct acpiphp_bridge *bridge;
unsigned int refcount;
};
static inline struct acpiphp_context *to_acpiphp_context(struct acpi_hotplug_context *hp)
{
return container_of(hp, struct acpiphp_context, hp);
}
static inline struct acpiphp_context *func_to_context(struct acpiphp_func *func)
{
return container_of(func, struct acpiphp_context, func);
}
static inline struct acpi_device *func_to_acpi_device(struct acpiphp_func *func)
{
return func_to_context(func)->hp.self;
}
static inline acpi_handle func_to_handle(struct acpiphp_func *func)
{
return func_to_acpi_device(func)->handle;
}
/*
* struct acpiphp_attention_info - device specific attention registration
*
* ACPI has no generic method of setting/getting attention status
* this allows for device specific driver registration
*/
struct acpiphp_attention_info
{
int (*set_attn)(struct hotplug_slot *slot, u8 status);
int (*get_attn)(struct hotplug_slot *slot, u8 *status);
struct module *owner;
};
/* ACPI _STA method value (ignore bit 4; battery present) */
#define ACPI_STA_ALL (0x0000000f)
/* slot flags */
#define SLOT_ENABLED (0x00000001)
#define SLOT_IS_GOING_AWAY (0x00000002)
/* function flags */
#define FUNC_HAS_STA (0x00000001)
#define FUNC_HAS_EJ0 (0x00000002)
#define FUNC_HAS_DCK (0x00000004)
/* function prototypes */
/* acpiphp_core.c */
int acpiphp_register_attention(struct acpiphp_attention_info*info);
int acpiphp_unregister_attention(struct acpiphp_attention_info *info);
int acpiphp_register_hotplug_slot(struct acpiphp_slot *slot, unsigned int sun);
void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *slot);
/* acpiphp_glue.c */
typedef int (*acpiphp_callback)(struct acpiphp_slot *slot, void *data);
int acpiphp_enable_slot(struct acpiphp_slot *slot);
int acpiphp_disable_slot(struct acpiphp_slot *slot);
u8 acpiphp_get_power_status(struct acpiphp_slot *slot);
u8 acpiphp_get_attention_status(struct acpiphp_slot *slot);
u8 acpiphp_get_latch_status(struct acpiphp_slot *slot);
u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot);
/* variables */
extern bool acpiphp_disabled;
#endif /* _ACPIPHP_H */