[net-next-2.6.git] / drivers / pci / hotplug / pciehp_acpi.c

/*
 * ACPI related functions for PCI Express Hot Plug driver.
 *
 * Copyright (C) 2008 Kenji Kaneshige
 * Copyright (C) 2008 Fujitsu Limited.
 *
 * 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.
 *
 */

#include <linux/acpi.h>
#include <linux/pci.h>
#include <linux/pci_hotplug.h>
#include <linux/slab.h>
#include "pciehp.h"

#define PCIEHP_DETECT_PCIE	(0)
#define PCIEHP_DETECT_ACPI	(1)
#define PCIEHP_DETECT_AUTO	(2)
#define PCIEHP_DETECT_DEFAULT	PCIEHP_DETECT_AUTO

struct dummy_slot {
	u32 number;
	struct list_head list;
};

static int slot_detection_mode;
static char *pciehp_detect_mode;
module_param(pciehp_detect_mode, charp, 0444);
MODULE_PARM_DESC(pciehp_detect_mode,
	 "Slot detection mode: pcie, acpi, auto\n"
	 "  pcie          - Use PCIe based slot detection\n"
	 "  acpi          - Use ACPI for slot detection\n"
	 "  auto(default) - Auto select mode. Use acpi option if duplicate\n"
	 "                  slot ids are found. Otherwise, use pcie option\n");

int pciehp_acpi_slot_detection_check(struct pci_dev *dev)
{
	if (slot_detection_mode != PCIEHP_DETECT_ACPI)
		return 0;
	if (acpi_pci_detect_ejectable(DEVICE_ACPI_HANDLE(&dev->dev)))
		return 0;
	return -ENODEV;
}

static int __init parse_detect_mode(void)
{
	if (!pciehp_detect_mode)
		return PCIEHP_DETECT_DEFAULT;
	if (!strcmp(pciehp_detect_mode, "pcie"))
		return PCIEHP_DETECT_PCIE;
	if (!strcmp(pciehp_detect_mode, "acpi"))
		return PCIEHP_DETECT_ACPI;
	if (!strcmp(pciehp_detect_mode, "auto"))
		return PCIEHP_DETECT_AUTO;
	warn("bad specifier '%s' for pciehp_detect_mode. Use default\n",
	     pciehp_detect_mode);
	return PCIEHP_DETECT_DEFAULT;
}

static int __initdata dup_slot_id;
static int __initdata acpi_slot_detected;
static struct list_head __initdata dummy_slots = LIST_HEAD_INIT(dummy_slots);

/* Dummy driver for dumplicate name detection */
static int __init dummy_probe(struct pcie_device *dev)
{
	int pos;
	u32 slot_cap;
	acpi_handle handle;
	struct dummy_slot *slot, *tmp;
	struct pci_dev *pdev = dev->port;
	/* Note: pciehp_detect_mode != PCIEHP_DETECT_ACPI here */
	if (pciehp_get_hp_hw_control_from_firmware(pdev))
		return -ENODEV;
	pos = pci_pcie_cap(pdev);
	if (!pos)
		return -ENODEV;
	pci_read_config_dword(pdev, pos + PCI_EXP_SLTCAP, &slot_cap);
	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
	if (!slot)
		return -ENOMEM;
	slot->number = slot_cap >> 19;
	list_for_each_entry(tmp, &dummy_slots, list) {
		if (tmp->number == slot->number)
			dup_slot_id++;
	}
	list_add_tail(&slot->list, &dummy_slots);
	handle = DEVICE_ACPI_HANDLE(&pdev->dev);
	if (!acpi_slot_detected && acpi_pci_detect_ejectable(handle))
		acpi_slot_detected = 1;
	return -ENODEV;         /* dummy driver always returns error */
}

static struct pcie_port_service_driver __initdata dummy_driver = {
        .name           = "pciehp_dummy",
	.port_type	= PCIE_ANY_PORT,
	.service	= PCIE_PORT_SERVICE_HP,
        .probe          = dummy_probe,
};

static int __init select_detection_mode(void)
{
	struct dummy_slot *slot, *tmp;
	pcie_port_service_register(&dummy_driver);
	pcie_port_service_unregister(&dummy_driver);
	list_for_each_entry_safe(slot, tmp, &dummy_slots, list) {
		list_del(&slot->list);
		kfree(slot);
	}
	if (acpi_slot_detected && dup_slot_id)
		return PCIEHP_DETECT_ACPI;
	return PCIEHP_DETECT_PCIE;
}

void __init pciehp_acpi_slot_detection_init(void)
{
	slot_detection_mode = parse_detect_mode();
	if (slot_detection_mode != PCIEHP_DETECT_AUTO)
		goto out;
	slot_detection_mode = select_detection_mode();
out:
	if (slot_detection_mode == PCIEHP_DETECT_ACPI)
		info("Using ACPI for slot detection.\n");
}
Commit	Line	Data
c9ffa5a5 KK	1	/*
	2	* ACPI related functions for PCI Express Hot Plug driver.
	3	*
	4	* Copyright (C) 2008 Kenji Kaneshige
	5	* Copyright (C) 2008 Fujitsu Limited.
	6	*
	7	* All rights reserved.
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2 of the License, or (at
	12	* your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful, but
	15	* WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
	17	* NON INFRINGEMENT. See the GNU General Public License for more
	18	* details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to the Free Software
	22	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	23	*
	24	*/
	25
	26	#include <linux/acpi.h>
e8c331e9 KK	27	#include <linux/pci.h>
e8c331e9 KK	28	#include <linux/pci_hotplug.h>
5a0e3ad6	29	#include <linux/slab.h>
c9ffa5a5 KK	30	#include "pciehp.h"
	31
	32	#define PCIEHP_DETECT_PCIE (0)
	33	#define PCIEHP_DETECT_ACPI (1)
e046cbd6 KK	34	#define PCIEHP_DETECT_AUTO (2)
e046cbd6 KK	35	#define PCIEHP_DETECT_DEFAULT PCIEHP_DETECT_AUTO
c9ffa5a5	36
8720d27d KK	37	struct dummy_slot {
	38	u32 number;
	39	struct list_head list;
	40	};
	41
c9ffa5a5 KK	42	static int slot_detection_mode;
	43	static char *pciehp_detect_mode;
	44	module_param(pciehp_detect_mode, charp, 0444);
	45	MODULE_PARM_DESC(pciehp_detect_mode,
e046cbd6 KK	46	"Slot detection mode: pcie, acpi, auto\n"
	47	" pcie - Use PCIe based slot detection\n"
	48	" acpi - Use ACPI for slot detection\n"
	49	" auto(default) - Auto select mode. Use acpi option if duplicate\n"
	50	" slot ids are found. Otherwise, use pcie option\n");
c9ffa5a5	51
c9ffa5a5 KK	52	int pciehp_acpi_slot_detection_check(struct pci_dev *dev)
	53	{
	54	if (slot_detection_mode != PCIEHP_DETECT_ACPI)
	55	return 0;
7f538669	56	if (acpi_pci_detect_ejectable(DEVICE_ACPI_HANDLE(&dev->dev)))
c9ffa5a5 KK	57	return 0;
	58	return -ENODEV;
	59	}
	60
	61	static int __init parse_detect_mode(void)
	62	{
	63	if (!pciehp_detect_mode)
	64	return PCIEHP_DETECT_DEFAULT;
	65	if (!strcmp(pciehp_detect_mode, "pcie"))
	66	return PCIEHP_DETECT_PCIE;
	67	if (!strcmp(pciehp_detect_mode, "acpi"))
	68	return PCIEHP_DETECT_ACPI;
e046cbd6 KK	69	if (!strcmp(pciehp_detect_mode, "auto"))
e046cbd6 KK	70	return PCIEHP_DETECT_AUTO;
c9ffa5a5 KK	71	warn("bad specifier '%s' for pciehp_detect_mode. Use default\n",
	72	pciehp_detect_mode);
	73	return PCIEHP_DETECT_DEFAULT;
	74	}
	75
e046cbd6 KK	76	static int __initdata dup_slot_id;
	77	static int __initdata acpi_slot_detected;
	78	static struct list_head __initdata dummy_slots = LIST_HEAD_INIT(dummy_slots);
	79
	80	/* Dummy driver for dumplicate name detection */
0516c8bc	81	static int __init dummy_probe(struct pcie_device *dev)
e046cbd6 KK	82	{
	83	int pos;
	84	u32 slot_cap;
7f538669	85	acpi_handle handle;
8720d27d	86	struct dummy_slot slot, tmp;
e046cbd6	87	struct pci_dev *pdev = dev->port;
e046cbd6 KK	88	/* Note: pciehp_detect_mode != PCIEHP_DETECT_ACPI here */
	89	if (pciehp_get_hp_hw_control_from_firmware(pdev))
	90	return -ENODEV;
1518c17a KK	91	pos = pci_pcie_cap(pdev);
1518c17a KK	92	if (!pos)
e046cbd6 KK	93	return -ENODEV;
e046cbd6 KK	94	pci_read_config_dword(pdev, pos + PCI_EXP_SLTCAP, &slot_cap);
0b3e7388 JL	95	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
	96	if (!slot)
	97	return -ENOMEM;
e046cbd6	98	slot->number = slot_cap >> 19;
8720d27d	99	list_for_each_entry(tmp, &dummy_slots, list) {
e046cbd6 KK	100	if (tmp->number == slot->number)
	101	dup_slot_id++;
	102	}
8720d27d	103	list_add_tail(&slot->list, &dummy_slots);
7f538669 AC	104	handle = DEVICE_ACPI_HANDLE(&pdev->dev);
7f538669 AC	105	if (!acpi_slot_detected && acpi_pci_detect_ejectable(handle))
e046cbd6 KK	106	acpi_slot_detected = 1;
	107	return -ENODEV; /* dummy driver always returns error */
	108	}
	109
	110	static struct pcie_port_service_driver __initdata dummy_driver = {
	111	.name = "pciehp_dummy",
22106368 RW	112	.port_type = PCIE_ANY_PORT,
22106368 RW	113	.service = PCIE_PORT_SERVICE_HP,
e046cbd6 KK	114	.probe = dummy_probe,
	115	};
	116
	117	static int __init select_detection_mode(void)
	118	{
8720d27d	119	struct dummy_slot slot, tmp;
e046cbd6 KK	120	pcie_port_service_register(&dummy_driver);
e046cbd6 KK	121	pcie_port_service_unregister(&dummy_driver);
8720d27d KK	122	list_for_each_entry_safe(slot, tmp, &dummy_slots, list) {
8720d27d KK	123	list_del(&slot->list);
e046cbd6 KK	124	kfree(slot);
	125	}
	126	if (acpi_slot_detected && dup_slot_id)
	127	return PCIEHP_DETECT_ACPI;
	128	return PCIEHP_DETECT_PCIE;
	129	}
	130
c9ffa5a5 KK	131	void __init pciehp_acpi_slot_detection_init(void)
	132	{
	133	slot_detection_mode = parse_detect_mode();
e046cbd6 KK	134	if (slot_detection_mode != PCIEHP_DETECT_AUTO)
	135	goto out;
	136	slot_detection_mode = select_detection_mode();
	137	out:
	138	if (slot_detection_mode == PCIEHP_DETECT_ACPI)
	139	info("Using ACPI for slot detection.\n");
c9ffa5a5	140	}