path: root/drivers/ata/libata-acpi.c

/*
 * libata-acpi.c
 * Provides ACPI support for PATA/SATA.
 *
 * Copyright (C) 2006 Intel Corp.
 * Copyright (C) 2006 Randy Dunlap
 */

#include <linux/module.h>
#include <linux/ata.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/acpi.h>
#include <linux/libata.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <scsi/scsi_device.h>
#include "libata.h"

#include <acpi/acpi_bus.h>

unsigned int ata_acpi_gtf_filter = ATA_ACPI_FILTER_DEFAULT;
module_param_named(acpi_gtf_filter, ata_acpi_gtf_filter, int, 0644);
MODULE_PARM_DESC(acpi_gtf_filter, "filter mask for ACPI _GTF commands, set to filter out (0x1=set xfermode, 0x2=lock/freeze lock, 0x4=DIPM, 0x8=FPDMA non-zero offset, 0x10=FPDMA DMA Setup FIS auto-activate)");

#define NO_PORT_MULT		0xffff
#define SATA_ADR(root, pmp)	(((root) << 16) | (pmp))

#define REGS_PER_GTF		7
struct ata_acpi_gtf {
	u8	tf[REGS_PER_GTF];	/* regs. 0x1f1 - 0x1f7 */
} __packed;

/*
 *	Helper - belongs in the PCI layer somewhere eventually
 */
static int is_pci_dev(struct device *dev)
{
	return (dev->bus == &pci_bus_type);
}

static void ata_acpi_clear_gtf(struct ata_device *dev)
{
	kfree(dev->gtf_cache);
	dev->gtf_cache = NULL;
}

/**
 * ata_ap_acpi_handle - provide the acpi_handle for an ata_port
 * @ap: the acpi_handle returned will correspond to this port
 *
 * Returns the acpi_handle for the ACPI namespace object corresponding to
 * the ata_port passed into the function, or NULL if no such object exists
 */
acpi_handle ata_ap_acpi_handle(struct ata_port *ap)
{
	if (ap->flags & ATA_FLAG_ACPI_SATA)
		return NULL;

	return ap->scsi_host ?
		DEVICE_ACPI_HANDLE(&ap->scsi_host->shost_gendev) : NULL;
}
EXPORT_SYMBOL(ata_ap_acpi_handle);

/**
 * ata_dev_acpi_handle - provide the acpi_handle for an ata_device
 * @dev: the acpi_device returned will correspond to this port
 *
 * Returns the acpi_handle for the ACPI namespace object corresponding to
 * the ata_device passed into the function, or NULL if no such object exists
 */
acpi_handle ata_dev_acpi_handle(struct ata_device *dev)
{
	acpi_integer adr;
	struct ata_port *ap = dev->link->ap;

	if (libata_noacpi || dev->flags & ATA_DFLAG_ACPI_DISABLED)
		return NULL;

	if (ap->flags & ATA_FLAG_ACPI_SATA) {
		if (!sata_pmp_attached(ap))
			adr = SATA_ADR(ap->port_no, NO_PORT_MULT);
		else
			adr = SATA_ADR(ap->port_no, dev->link->pmp);
		return acpi_get_child(DEVICE_ACPI_HANDLE(ap->host->dev), adr);
	} else
		return acpi_get_child(ata_ap_acpi_handle(ap), dev->devno);
}
EXPORT_SYMBOL(ata_dev_acpi_handle);

/* @ap and @dev are the same as ata_acpi_handle_hotplug() */
static void ata_acpi_detach_device(struct ata_port *ap, struct ata_device *dev)
{
	if (dev)
		dev->flags |= ATA_DFLAG_DETACH;
	else {
		struct ata_link *tlink;
		struct ata_device *tdev;

		ata_for_each_link(tlink, ap, EDGE)
			ata_for_each_dev(tdev, tlink, ALL)
				tdev->flags |= ATA_DFLAG_DETACH;
	}

	ata_port_schedule_eh(ap);
}

/**
 * ata_acpi_handle_hotplug - ACPI event handler backend
 * @ap: ATA port ACPI event occurred
 * @dev: ATA device ACPI event occurred (can be NULL)
 * @event: ACPI event which occurred
 *
 * All ACPI bay / device realted events end up in this function.  If
 * the event is port-wide @dev is NULL.  If the event is specific to a
 * device, @dev points to it.
 *
 * Hotplug (as opposed to unplug) notification is always handled as
 * port-wide while unplug only kills the target device on device-wide
 * event.
 *
 * LOCKING:
 * ACPI notify handler context.  May sleep.
 */
static void ata_acpi_handle_hotplug(struct ata_port *ap, struct ata_device *dev,
				    u32 event)
{
	struct ata_eh_info *ehi = &ap->link.eh_info;
	int wait = 0;
	unsigned long flags