linux/drivers/pci/pcie/pme.c

// SPDX-License-Identifier: GPL-2.0
/*
 * PCIe Native PME support
 *
 * Copyright (C) 2007 - 2009 Intel Corp
 * Copyright (C) 2007 - 2009 Shaohua Li <[email protected]>
 * Copyright (C) 2009 Rafael J. Wysocki <[email protected]>, Novell Inc.
 */

#define dev_fmt(fmt) …

#include <linux/bitfield.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/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)
{ … }
__setup(…);

struct pcie_pme_service_data { … };

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * pcie_pme_can_wakeup - Set the wakeup capability flag.
 * @dev: PCI device to handle.
 * @ign: Ignored.
 */
static int pcie_pme_can_wakeup(struct pci_dev *dev, void *ign)
{ … }

/**
 * pcie_pme_mark_devices - Set the wakeup 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.
 */
static void pcie_pme_mark_devices(struct pci_dev *port)
{ … }

/**
 * 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)
{ … }

static bool pcie_pme_check_wakeup(struct pci_bus *bus)
{ … }

static void pcie_pme_disable_interrupt(struct pci_dev *port,
				       struct pcie_pme_service_data *data)
{ … }

/**
 * pcie_pme_suspend - Suspend PCIe PME service device.
 * @srv: PCIe service device to suspend.
 */
static int pcie_pme_suspend(struct pcie_device *srv)
{ … }

/**
 * pcie_pme_resume - Resume PCIe PME service device.
 * @srv: PCIe service device to resume.
 */
static int pcie_pme_resume(struct pcie_device *srv)
{ … }

/**
 * pcie_pme_remove - Prepare PCIe PME service device for removal.
 * @srv: PCIe service device to remove.
 */
static void pcie_pme_remove(struct pcie_device *srv)
{ … }

static struct pcie_port_service_driver pcie_pme_driver = …;

/**
 * pcie_pme_init - Register the PCIe PME service driver.
 */
int __init pcie_pme_init(void)
{ … }