[deliverable/linux.git] / drivers / pci / pcie / pme.c

/*
 * PCIe Native PME support
 *
 * Copyright (C) 2007 - 2009 Intel Corp
 * Copyright (C) 2007 - 2009 Shaohua Li <shaohua.li@intel.com>
 * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License V2.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/pcieport_if.h>
#include <linux/acpi.h>
#include <linux/pci-acpi.h>
#include <linux/pm_runtime.h>

#include "../pci.h"
#include "portdrv.h"

/*
 * If this switch is set, MSI will not be used for PCIe PME signaling.  This
 * causes the PCIe port driver to use INTx interrupts only, but it turns out
 * that using MSI for PCIe PME signaling doesn't play well with PCIe PME-based
 * wake-up from system sleep states.
 */
bool pcie_pme_msi_disabled;

static int __init pcie_pme_setup(char *str)
{
	if (!strncmp(str, "nomsi", 5))
		pcie_pme_msi_disabled = true;

	return 1;
}
__setup("pcie_pme=", pcie_pme_setup);

struct pcie_pme_service_data {
	spinlock_t lock;
	struct pcie_device *srv;
	struct work_struct work;
	bool noirq; /* Don't enable the PME interrupt used by this service. */
};

/**
 * pcie_pme_interrupt_enable - Enable/disable PCIe PME interrupt generation.
 * @dev: PCIe root port or event collector.
 * @enable: Enable or disable the interrupt.
 */
void pcie_pme_interrupt_enable(struct pci_dev *dev, bool enable)
{
	int rtctl_pos;
	u16 rtctl;

	rtctl_pos = pci_pcie_cap(dev) + PCI_EXP_RTCTL;

	pci_read_config_word(dev, rtctl_pos, &rtctl);
	if (enable)
		rtctl |= PCI_EXP_RTCTL_PMEIE;
	else
		rtctl &= ~PCI_EXP_RTCTL_PMEIE;
	pci_write_config_word(dev, rtctl_pos, rtctl);
}

/**
 * pcie_pme_walk_bus - Scan a PCI bus for devices asserting PME#.
 * @bus: PCI bus to scan.
 *
 * Scan given PCI bus and all buses under it for devices asserting PME#.
 */
static bool pcie_pme_walk_bus(struct pci_bus *bus)
{
	struct pci_dev *dev;
	bool ret = false;

	list_for_each_entry(dev, &bus->devices, bus_list) {
		/* Skip PCIe devices in case we started from a root port. */
		if (!pci_is_pcie(dev) && pci_check_pme_status(dev)) {
			pci_wakeup_event(dev);
			pm_request_resume(&dev->dev);
			ret = true;
		}

		if (dev->subordinate && pcie_pme_walk_bus(dev->subordinate))
			ret = true;
	}

	return ret;
}

/**
 * pcie_pme_from_pci_bridge - Check if PCIe-PCI bridge generated a PME.
 * @bus: Secondary bus of the bridge.
 * @devfn: Device/function number to check.
 *
 * PME from PCI devices under a PCIe-PCI bridge may be converted to an in-band
 * PCIe PME message.  In such that case the bridge should use the Requester ID
 * of device/function number 0 on its secondary bus.
 */
static bool pcie_pme_from_pci_bridge(struct pci_bus *bus, u8 devfn)
{
	struct pci_dev *dev;
	bool found = false;

	if (devfn)
		return false;

	dev = pci_dev_get(bus->self);
	if (!dev)
		return false;

	if (pci_is_pcie(dev) && dev->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE) {
		down_read(&pci_bus_sem);
		if (pcie_pme_walk_bus(bus))
			found = true;
		up_read(&pci_bus_sem);
	}

	pci_dev_put(dev);
	return found;
}

/**
 * pcie_pme_handle_request - Find device that generated PME and handle it.
 * @port: Root port or event collector that generated the PME interrupt.
 * @req_id: PCIe Requester ID of the device that generated the PME.
 */
static void pcie_pme_handle_request(struct pci_dev *port, u16 req_id)
{
	u8 busnr = req_id >> 8, devfn = req_id & 0xff;
	struct pci_bus *bus;
	struct pci_dev *dev;
	bool found = false;

	/* First, check if the PME is from the root port itself. */
	if (port->devfn == devfn && port->bus->number == busnr) {
		if (pci_check_pme_status(port)) {
			pm_request_resume(&port->dev);
			found = true;
		} else {
			/*
			 * Apparently, the root port generated the PME on behalf
			 * of a non-PCIe device downstream.  If this is done by
			 * a root port, the Requester ID field in its status
			 * register may contain either the root port's, or the
			 * source device's information (PCI Express Base
			 * Specification, Rev. 2.0, Section 6.1.9).
			 */
			down_read(&pci_bus_sem);
			found = pcie_pme_walk_bus(port->subordinate);
			up_read(&pci_bus_sem);
		}
		goto out;
	}

	/* Second, find the bus the source device is on. */
	bus = pci_find_bus(pci_domain_nr(port->bus), busnr);
	if (!bus)
		goto out;

	/* Next, check if the PME is from a PCIe-PCI bridge. */
	found = pcie_pme_from_pci_bridge(bus, devfn);
	if (found)
		goto out;

	/* Finally, try to find the PME source on the bus. */
	down_read(&pci_bus_sem);
	list_for_each_entry(dev, &bus->devices, bus_list) {
		pci_dev_get(dev);
		if (dev->devfn == devfn) {
			found = true;
			break;
		}
		pci_dev_put(dev);
	}
	up_read(&pci_bus_sem);

	if (found) {
		/* The device is there, but we have to check its PME status. */
		found = pci_check_pme_status(dev);
		if (found) {
			pci_wakeup_event(dev);
			pm_request_resume(&dev->dev);
		}
		pci_dev_put(dev);
	} else if (devfn) {
		/*
		 * The device is not there, but we can still try to recover by
		 * assuming that the PME was reported by a PCIe-PCI bridge that
		 * used devfn different from zero.
		 */
		dev_dbg(&port->dev, "PME interrupt generated for "
			"non-existent device %02x:%02x.%d\n",
			busnr, PCI_SLOT(devfn), PCI_FUNC(devfn));
		found = pcie_pme_from_pci_bridge(bus, 0);
	}

 out:
	if (!found)
		dev_dbg(&port->dev, "Spurious native PME interrupt!\n");
}

/**
 * pcie_pme_work_fn - Work handler for PCIe PME interrupt.
 * @work: Work structure giving access to service data.
 */
static void pcie_pme_work_fn(struct work_struct *work)
{
	struct pcie_pme_service_data *data =
			container_of(work, struct pcie_pme_service_data, work);
	struct pci_dev *port = data->srv->port;
	int rtsta_pos;
	u32 rtsta;

	rtsta_pos = pci_pcie_cap(port) + PCI_EXP_RTSTA;

	spin_lock_irq(&data->lock);

	for (;;) {
		if (data->noirq)
			break;

		pci_read_config_dword(port, rtsta_pos, &rtsta);
		if (rtsta & PCI_EXP_RTSTA_PME) {
			/*
			 * Clear PME status of the port.  If there are other
			 * pending PMEs, the status will be set again.
			 */
			pcie_clear_root_pme_status(port);

			spin_unlock_irq(&data->lock);
			pcie_pme_handle_request(port, rtsta & 0xffff);
			spin_lock_irq(&data->lock);

			continue;
		}

		/* No need to loop if there are no more PMEs pending. */
		if (!(rtsta & PCI_EXP_RTSTA_PENDING))
			break;

		spin_unlock_irq(&data->lock);
		cpu_relax();
		spin_lock_irq(&data->lock);
	}

	if (!data->noirq)
		pcie_pme_interrupt_enable(port, true);

	spin_unlock_irq(&data->lock);
}

/**
 * pcie_pme_irq - Interrupt handler for PCIe root port PME interrupt.
 * @irq: Interrupt vector.
 * @context: Interrupt context pointer.
 */
static irqreturn_t pcie_pme_irq(int irq, void *context)
{
	struct pci_dev *port;
	struct pcie_pme_service_data *data;
	int rtsta_pos;
	u32 rtsta;
	unsigned long flags;

	port = ((struct pcie_device *)context)->port;
	data = get_service_data((struct pcie_device *)context);

	rtsta_pos = pci_pcie_cap(port) + PCI_EXP_RTSTA;

	spin_lock_irqsave(&data->lock, flags);
	pci_read_config_dword(port, rtsta_pos, &rtsta);

	if (!(rtsta & PCI_EXP_RTSTA_PME)) {
		spin_unlock_irqrestore(&data->lock, flags);
		return IRQ_NONE;
	}

	pcie_pme_interrupt_enable(port, false);
	spin_unlock_irqrestore(&data->lock, flags);

	/* We don't use pm_wq, because it's freezable. */
	schedule_work(&data->work);

	return IRQ_HANDLED;
}

/**
 * pcie_pme_set_native - Set the PME interrupt flag for given device.
 * @dev: PCI device to handle.
 * @ign: Ignored.
 */
static int pcie_pme_set_native(struct pci_dev *dev, void *ign)
{
	dev_info(&dev->dev, "Signaling PME through PCIe PME interrupt\n");

	device_set_run_wake(&dev->dev, true);
	dev->pme_interrupt = true;
	return 0;
}

/**
 * pcie_pme_mark_devices - Set the PME interrupt flag for devices below a port.
 * @port: PCIe root port or event collector to handle.
 *
 * For each device below given root port, including the port itself (or for each
 * root complex integrated endpoint if @port is a root complex event collector)
 * set the flag indicating that it can signal run-time wake-up events via PCIe
 * PME interrupts.
 */
static void pcie_pme_mark_devices(struct pci_dev *port)
{
	pcie_pme_set_native(port, NULL);
	if (port->subordinate) {
		pci_walk_bus(port->subordinate, pcie_pme_set_native, NULL);
	} else {
		struct pci_bus *bus = port->bus;
		struct pci_dev *dev;

		/* Check if this is a root port event collector. */
		if (port->pcie_type != PCI_EXP_TYPE_RC_EC || !bus)
			return;

		down_read(&pci_bus_sem);
		list_for_each_entry(dev, &bus->devices, bus_list)
			if (pci_is_pcie(dev)
			    && dev->pcie_type == PCI_EXP_TYPE_RC_END)
				pcie_pme_set_native(dev, NULL);
		up_read(&pci_bus_sem);
	}
}

/**
 * pcie_pme_probe - Initialize PCIe PME service for given root port.
 * @srv: PCIe service to initialize.
 */
static int pcie_pme_probe(struct pcie_device *srv)
{
	struct pci_dev *port;
	struct pcie_pme_service_data *data;
	int ret;

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	spin_lock_init(&data->lock);
	INIT_WORK(&data->work, pcie_pme_work_fn);
	data->srv = srv;
	set_service_data(srv, data);

	port = srv->port;
	pcie_pme_interrupt_enable(port, false);
	pcie_clear_root_pme_status(port);

	ret = request_irq(srv->irq, pcie_pme_irq, IRQF_SHARED, "PCIe PME", srv);
	if (ret) {
		kfree(data);
	} else {
		pcie_pme_mark_devices(port);
		pcie_pme_interrupt_enable(port, true);
	}

	return ret;
}

/**
 * pcie_pme_suspend - Suspend PCIe PME service device.
 * @srv: PCIe service device to suspend.
 */
static int pcie_pme_suspend(struct pcie_device *srv)
{
	struct pcie_pme_service_data *data = get_service_data(srv);
	struct pci_dev *port = srv->port;

	spin_lock_irq(&data->lock);
	pcie_pme_interrupt_enable(port, false);
	pcie_clear_root_pme_status(port);
	data->noirq = true;
	spin_unlock_irq(&data->lock);

	synchronize_irq(srv->irq);

	return 0;
}

/**
 * pcie_pme_resume - Resume PCIe PME service device.
 * @srv - PCIe service device to resume.
 */
static int pcie_pme_resume(struct pcie_device *srv)
{
	struct pcie_pme_service_data *data = get_service_data(srv);
	struct pci_dev *port = srv->port;

	spin_lock_irq(&data->lock);
	data->noirq = false;
	pcie_clear_root_pme_status(port);
	pcie_pme_interrupt_enable(port, true);
	spin_unlock_irq(&data->lock);

	return 0;
}

/**
 * pcie_pme_remove - Prepare PCIe PME service device for removal.
 * @srv - PCIe service device to resume.
 */
static void pcie_pme_remove(struct pcie_device *srv)
{
	pcie_pme_suspend(srv);
	free_irq(srv->irq, srv);
	kfree(get_service_data(srv));
}

static struct pcie_port_service_driver pcie_pme_driver = {
	.name		= "pcie_pme",
	.port_type 	= PCI_EXP_TYPE_ROOT_PORT,
	.service 	= PCIE_PORT_SERVICE_PME,

	.probe		= pcie_pme_probe,
	.suspend	= pcie_pme_suspend,
	.resume		= pcie_pme_resume,
	.remove		= pcie_pme_remove,
};

/**
 * pcie_pme_service_init - Register the PCIe PME service driver.
 */
static int __init pcie_pme_service_init(void)
{
	return pcie_port_service_register(&pcie_pme_driver);
}

module_init(pcie_pme_service_init);
Commit	Line	Data
c7f48656 RW	1	/*
	2	* PCIe Native PME support
	3	*
	4	* Copyright (C) 2007 - 2009 Intel Corp
	5	* Copyright (C) 2007 - 2009 Shaohua Li <shaohua.li@intel.com>
	6	* Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
	7	*
	8	* This file is subject to the terms and conditions of the GNU General Public
	9	* License V2. See the file "COPYING" in the main directory of this archive
	10	* for more details.
	11	*/
	12
	13	#include <linux/module.h>
	14	#include <linux/pci.h>
	15	#include <linux/kernel.h>
	16	#include <linux/errno.h>
5a0e3ad6	17	#include <linux/slab.h>
c7f48656 RW	18	#include <linux/init.h>
	19	#include <linux/interrupt.h>
	20	#include <linux/device.h>
	21	#include <linux/pcieport_if.h>
	22	#include <linux/acpi.h>
	23	#include <linux/pci-acpi.h>
	24	#include <linux/pm_runtime.h>
	25
271fb719 RW	26	#include "../pci.h"
271fb719 RW	27	#include "portdrv.h"
c7f48656	28
c39fae14 RW	29	/*
	30	* If this switch is set, MSI will not be used for PCIe PME signaling. This
	31	* causes the PCIe port driver to use INTx interrupts only, but it turns out
	32	* that using MSI for PCIe PME signaling doesn't play well with PCIe PME-based
	33	* wake-up from system sleep states.
	34	*/
	35	bool pcie_pme_msi_disabled;
	36
c7f48656 RW	37	static int __init pcie_pme_setup(char *str)
c7f48656 RW	38	{
28eb5f27 RW	39	if (!strncmp(str, "nomsi", 5))
28eb5f27 RW	40	pcie_pme_msi_disabled = true;
b27759f8	41
c7f48656 RW	42	return 1;
	43	}
	44	__setup("pcie_pme=", pcie_pme_setup);
	45
c7f48656 RW	46	struct pcie_pme_service_data {
	47	spinlock_t lock;
	48	struct pcie_device *srv;
	49	struct work_struct work;
	50	bool noirq; /* Don't enable the PME interrupt used by this service. */
	51	};
	52
	53	/**
	54	* pcie_pme_interrupt_enable - Enable/disable PCIe PME interrupt generation.
	55	* @dev: PCIe root port or event collector.
	56	* @enable: Enable or disable the interrupt.
	57	*/
28eb5f27	58	void pcie_pme_interrupt_enable(struct pci_dev *dev, bool enable)
c7f48656 RW	59	{
	60	int rtctl_pos;
	61	u16 rtctl;
	62
b16694f7	63	rtctl_pos = pci_pcie_cap(dev) + PCI_EXP_RTCTL;
c7f48656 RW	64
	65	pci_read_config_word(dev, rtctl_pos, &rtctl);
	66	if (enable)
	67	rtctl \|= PCI_EXP_RTCTL_PMEIE;
	68	else
	69	rtctl &= ~PCI_EXP_RTCTL_PMEIE;
	70	pci_write_config_word(dev, rtctl_pos, rtctl);
	71	}
	72
c7f48656 RW	73	/**
	74	* pcie_pme_walk_bus - Scan a PCI bus for devices asserting PME#.
	75	* @bus: PCI bus to scan.
	76	*
	77	* Scan given PCI bus and all buses under it for devices asserting PME#.
	78	*/
	79	static bool pcie_pme_walk_bus(struct pci_bus *bus)
	80	{
	81	struct pci_dev *dev;
	82	bool ret = false;
	83
	84	list_for_each_entry(dev, &bus->devices, bus_list) {
	85	/* Skip PCIe devices in case we started from a root port. */
552be54c	86	if (!pci_is_pcie(dev) && pci_check_pme_status(dev)) {
c125e96f	87	pci_wakeup_event(dev);
0f953bf6	88	pm_request_resume(&dev->dev);
c7f48656 RW	89	ret = true;
	90	}
	91
	92	if (dev->subordinate && pcie_pme_walk_bus(dev->subordinate))
	93	ret = true;
	94	}
	95
	96	return ret;
	97	}
	98
	99	/**
	100	* pcie_pme_from_pci_bridge - Check if PCIe-PCI bridge generated a PME.
	101	* @bus: Secondary bus of the bridge.
	102	* @devfn: Device/function number to check.
	103	*
	104	* PME from PCI devices under a PCIe-PCI bridge may be converted to an in-band
	105	* PCIe PME message. In such that case the bridge should use the Requester ID
	106	* of device/function number 0 on its secondary bus.
	107	*/
	108	static bool pcie_pme_from_pci_bridge(struct pci_bus *bus, u8 devfn)
	109	{
	110	struct pci_dev *dev;
	111	bool found = false;
	112
	113	if (devfn)
	114	return false;
	115
	116	dev = pci_dev_get(bus->self);
	117	if (!dev)
	118	return false;
	119
552be54c	120	if (pci_is_pcie(dev) && dev->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE) {
c7f48656 RW	121	down_read(&pci_bus_sem);
	122	if (pcie_pme_walk_bus(bus))
	123	found = true;
	124	up_read(&pci_bus_sem);
	125	}
	126
	127	pci_dev_put(dev);
	128	return found;
	129	}
	130
	131	/**
	132	* pcie_pme_handle_request - Find device that generated PME and handle it.
	133	* @port: Root port or event collector that generated the PME interrupt.
	134	* @req_id: PCIe Requester ID of the device that generated the PME.
	135	*/
	136	static void pcie_pme_handle_request(struct pci_dev *port, u16 req_id)
	137	{
	138	u8 busnr = req_id >> 8, devfn = req_id & 0xff;
	139	struct pci_bus *bus;
	140	struct pci_dev *dev;
	141	bool found = false;
	142
	143	/* First, check if the PME is from the root port itself. */
	144	if (port->devfn == devfn && port->bus->number == busnr) {
	145	if (pci_check_pme_status(port)) {
	146	pm_request_resume(&port->dev);
	147	found = true;
	148	} else {
	149	/*
	150	* Apparently, the root port generated the PME on behalf
	151	* of a non-PCIe device downstream. If this is done by
	152	* a root port, the Requester ID field in its status
	153	* register may contain either the root port's, or the
	154	* source device's information (PCI Express Base
	155	* Specification, Rev. 2.0, Section 6.1.9).
	156	*/
	157	down_read(&pci_bus_sem);
	158	found = pcie_pme_walk_bus(port->subordinate);
	159	up_read(&pci_bus_sem);
	160	}
	161	goto out;
	162	}
	163
	164	/* Second, find the bus the source device is on. */
	165	bus = pci_find_bus(pci_domain_nr(port->bus), busnr);
	166	if (!bus)
	167	goto out;
	168
	169	/* Next, check if the PME is from a PCIe-PCI bridge. */
	170	found = pcie_pme_from_pci_bridge(bus, devfn);
	171	if (found)
	172	goto out;
	173
	174	/* Finally, try to find the PME source on the bus. */
	175	down_read(&pci_bus_sem);
	176	list_for_each_entry(dev, &bus->devices, bus_list) {
	177	pci_dev_get(dev);
	178	if (dev->devfn == devfn) {
	179	found = true;
	180	break;
	181	}
	182	pci_dev_put(dev);
	183	}
	184	up_read(&pci_bus_sem);
185
186	if (found) {
187	/* The device is there, but we have to check its PME status. */
188	found = pci_check_pme_status(dev);
c125e96f	189	if (found) {
c125e96f	190	pci_wakeup_event(dev);
0f953bf6	191	pm_request_resume(&dev->dev);
c125e96f	192	}
c7f48656 RW	193	pci_dev_put(dev);
	194	} else if (devfn) {
	195	/*
	196	* The device is not there, but we can still try to recover by
	197	* assuming that the PME was reported by a PCIe-PCI bridge that
	198	* used devfn different from zero.
	199	*/
	200	dev_dbg(&port->dev, "PME interrupt generated for "
	201	"non-existent device %02x:%02x.%d\n",
	202	busnr, PCI_SLOT(devfn), PCI_FUNC(devfn));
	203	found = pcie_pme_from_pci_bridge(bus, 0);
	204	}
	205
	206	out:
	207	if (!found)
	208	dev_dbg(&port->dev, "Spurious native PME interrupt!\n");
	209	}
	210
	211	/**
	212	* pcie_pme_work_fn - Work handler for PCIe PME interrupt.
	213	* @work: Work structure giving access to service data.
	214	*/
	215	static void pcie_pme_work_fn(struct work_struct *work)
	216	{
	217	struct pcie_pme_service_data *data =
	218	container_of(work, struct pcie_pme_service_data, work);
	219	struct pci_dev *port = data->srv->port;
	220	int rtsta_pos;
	221	u32 rtsta;
	222
b16694f7	223	rtsta_pos = pci_pcie_cap(port) + PCI_EXP_RTSTA;
c7f48656 RW	224
	225	spin_lock_irq(&data->lock);
	226
	227	for (;;) {
	228	if (data->noirq)
	229	break;
	230
	231	pci_read_config_dword(port, rtsta_pos, &rtsta);
	232	if (rtsta & PCI_EXP_RTSTA_PME) {
	233	/*
	234	* Clear PME status of the port. If there are other
	235	* pending PMEs, the status will be set again.
	236	*/
fe31e697	237	pcie_clear_root_pme_status(port);
c7f48656 RW	238
	239	spin_unlock_irq(&data->lock);
	240	pcie_pme_handle_request(port, rtsta & 0xffff);
	241	spin_lock_irq(&data->lock);
	242
	243	continue;
	244	}
	245
	246	/* No need to loop if there are no more PMEs pending. */
	247	if (!(rtsta & PCI_EXP_RTSTA_PENDING))
	248	break;
	249
	250	spin_unlock_irq(&data->lock);
	251	cpu_relax();
	252	spin_lock_irq(&data->lock);
	253	}
	254
	255	if (!data->noirq)
	256	pcie_pme_interrupt_enable(port, true);
	257
	258	spin_unlock_irq(&data->lock);
	259	}
	260
	261	/**
	262	* pcie_pme_irq - Interrupt handler for PCIe root port PME interrupt.
	263	* @irq: Interrupt vector.
	264	* @context: Interrupt context pointer.
	265	*/
	266	static irqreturn_t pcie_pme_irq(int irq, void *context)
	267	{
	268	struct pci_dev *port;
	269	struct pcie_pme_service_data *data;
	270	int rtsta_pos;
	271	u32 rtsta;
	272	unsigned long flags;
	273
	274	port = ((struct pcie_device *)context)->port;
	275	data = get_service_data((struct pcie_device *)context);
	276
b16694f7	277	rtsta_pos = pci_pcie_cap(port) + PCI_EXP_RTSTA;
c7f48656 RW	278
	279	spin_lock_irqsave(&data->lock, flags);
	280	pci_read_config_dword(port, rtsta_pos, &rtsta);
	281
	282	if (!(rtsta & PCI_EXP_RTSTA_PME)) {
	283	spin_unlock_irqrestore(&data->lock, flags);
	284	return IRQ_NONE;
	285	}
	286
	287	pcie_pme_interrupt_enable(port, false);
	288	spin_unlock_irqrestore(&data->lock, flags);
	289
	290	/* We don't use pm_wq, because it's freezable. */
	291	schedule_work(&data->work);
	292
	293	return IRQ_HANDLED;
	294	}
	295
	296	/**
	297	* pcie_pme_set_native - Set the PME interrupt flag for given device.
	298	* @dev: PCI device to handle.
	299	* @ign: Ignored.
	300	*/
	301	static int pcie_pme_set_native(struct pci_dev dev, void ign)
	302	{
	303	dev_info(&dev->dev, "Signaling PME through PCIe PME interrupt\n");
	304
	305	device_set_run_wake(&dev->dev, true);
	306	dev->pme_interrupt = true;
	307	return 0;
	308	}
	309
	310	/**
	311	* pcie_pme_mark_devices - Set the PME interrupt flag for devices below a port.
	312	* @port: PCIe root port or event collector to handle.
	313	*
	314	* For each device below given root port, including the port itself (or for each
	315	* root complex integrated endpoint if @port is a root complex event collector)
	316	* set the flag indicating that it can signal run-time wake-up events via PCIe
	317	* PME interrupts.
	318	*/
	319	static void pcie_pme_mark_devices(struct pci_dev *port)
	320	{
	321	pcie_pme_set_native(port, NULL);
	322	if (port->subordinate) {
	323	pci_walk_bus(port->subordinate, pcie_pme_set_native, NULL);
	324	} else {
	325	struct pci_bus *bus = port->bus;
	326	struct pci_dev *dev;
	327
	328	/* Check if this is a root port event collector. */
	329	if (port->pcie_type != PCI_EXP_TYPE_RC_EC \|\| !bus)
	330	return;
	331
	332	down_read(&pci_bus_sem);
	333	list_for_each_entry(dev, &bus->devices, bus_list)
552be54c	334	if (pci_is_pcie(dev)
c7f48656 RW	335	&& dev->pcie_type == PCI_EXP_TYPE_RC_END)
	336	pcie_pme_set_native(dev, NULL);
	337	up_read(&pci_bus_sem);
	338	}
	339	}
	340
	341	/**
	342	* pcie_pme_probe - Initialize PCIe PME service for given root port.
	343	* @srv: PCIe service to initialize.
	344	*/
	345	static int pcie_pme_probe(struct pcie_device *srv)
	346	{
	347	struct pci_dev *port;
	348	struct pcie_pme_service_data *data;
	349	int ret;
	350
c7f48656 RW	351	data = kzalloc(sizeof(*data), GFP_KERNEL);
	352	if (!data)
	353	return -ENOMEM;
	354
	355	spin_lock_init(&data->lock);
	356	INIT_WORK(&data->work, pcie_pme_work_fn);
	357	data->srv = srv;
	358	set_service_data(srv, data);
	359
	360	port = srv->port;
	361	pcie_pme_interrupt_enable(port, false);
fe31e697	362	pcie_clear_root_pme_status(port);
c7f48656 RW	363
	364	ret = request_irq(srv->irq, pcie_pme_irq, IRQF_SHARED, "PCIe PME", srv);
	365	if (ret) {
	366	kfree(data);
	367	} else {
	368	pcie_pme_mark_devices(port);
	369	pcie_pme_interrupt_enable(port, true);
	370	}
	371
	372	return ret;
	373	}
	374
	375	/**
	376	* pcie_pme_suspend - Suspend PCIe PME service device.
	377	* @srv: PCIe service device to suspend.
	378	*/
	379	static int pcie_pme_suspend(struct pcie_device *srv)
	380	{
	381	struct pcie_pme_service_data *data = get_service_data(srv);
	382	struct pci_dev *port = srv->port;
	383
	384	spin_lock_irq(&data->lock);
	385	pcie_pme_interrupt_enable(port, false);
fe31e697	386	pcie_clear_root_pme_status(port);
c7f48656 RW	387	data->noirq = true;
	388	spin_unlock_irq(&data->lock);
	389
	390	synchronize_irq(srv->irq);
	391
	392	return 0;
	393	}
	394
	395	/**
	396	* pcie_pme_resume - Resume PCIe PME service device.
	397	* @srv - PCIe service device to resume.
	398	*/
	399	static int pcie_pme_resume(struct pcie_device *srv)
	400	{
	401	struct pcie_pme_service_data *data = get_service_data(srv);
	402	struct pci_dev *port = srv->port;
	403
	404	spin_lock_irq(&data->lock);
	405	data->noirq = false;
fe31e697	406	pcie_clear_root_pme_status(port);
c7f48656 RW	407	pcie_pme_interrupt_enable(port, true);
	408	spin_unlock_irq(&data->lock);
	409
	410	return 0;
	411	}
	412
	413	/**
	414	* pcie_pme_remove - Prepare PCIe PME service device for removal.
	415	* @srv - PCIe service device to resume.
	416	*/
	417	static void pcie_pme_remove(struct pcie_device *srv)
	418	{
	419	pcie_pme_suspend(srv);
	420	free_irq(srv->irq, srv);
	421	kfree(get_service_data(srv));
	422	}
	423
	424	static struct pcie_port_service_driver pcie_pme_driver = {
	425	.name = "pcie_pme",
	426	.port_type = PCI_EXP_TYPE_ROOT_PORT,
	427	.service = PCIE_PORT_SERVICE_PME,
	428
	429	.probe = pcie_pme_probe,
	430	.suspend = pcie_pme_suspend,
	431	.resume = pcie_pme_resume,
	432	.remove = pcie_pme_remove,
	433	};
	434
	435	/**
	436	* pcie_pme_service_init - Register the PCIe PME service driver.
	437	*/
	438	static int __init pcie_pme_service_init(void)
	439	{
28eb5f27	440	return pcie_port_service_register(&pcie_pme_driver);
c7f48656 RW	441	}
	442
	443	module_init(pcie_pme_service_init);