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 <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_acpi_associate_sata_port - associate SATA port with ACPI objects
 * @ap: target SATA port
 *
 * Look up ACPI objects associated with @ap and initialize acpi_handle
 * fields of @ap, the port and devices accordingly.
 *
 * LOCKING:
 * EH context.
 *
 * RETURNS:
 * 0 on success, -errno on failure.
 */
void ata_acpi_associate_sata_port(struct ata_port *ap)
{
	WARN_ON(!(ap->flags & ATA_FLAG_ACPI_SATA));

	if (!sata_pmp_attached(ap)) {
		u64 adr = SATA_ADR(ap->port_no, NO_PORT_MULT);

		ap->link.device->acpi_handle =
			acpi_get_child(ap->host->acpi_handle, adr);
	} else {
		struct ata_link *link;

		ap->link.device->acpi_handle = NULL;

		ata_for_each_link(link, ap, EDGE) {
			u64 adr = SATA_ADR(ap->port_no, link->pmp);

			link->device->acpi_handle =
				acpi_get_child(ap->host->acpi_handle, adr);
		}
	}
}

static void ata_acpi_associate_ide_port(struct ata_port *ap)
{
	int max_devices, i;

	ap->acpi_handle = acpi_get_child(ap->host->acpi_handle, ap->port_no);
	if (!ap->acpi_handle)
		return;

	max_devices = 1;
	if (ap->flags & ATA_FLAG_SLAVE_POSS)
		max_devices++;

	for (i = 0; i < max_devices; i++) {
		struct ata_device *dev = &ap->link.device[i];

		dev->acpi_handle = acpi_get_child(ap->acpi_handle, i);
	}

	if (ata_acpi_gtm(ap, &ap->__acpi_init_gtm) == 0)
		ap->pflags |= ATA_PFLAG_INIT_GTM_VALID;
}

/* @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;
	acpi_handle handle;

	if (dev)
		handle = dev->acpi_handle;
	else
		handle = ap->acpi_handle;

	spin_lock_irqsave(ap->lock, flags);
	/*
	 * When dock driver calls into the routine, it will always use
	 * ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
	 * ACPI_NOTIFY_EJECT_REQUEST for remove
	 */
	switch (event) {
	case ACPI_NOTIFY_BUS_CHECK:
	case ACPI_NOTIFY_DEVICE_CHECK:
		ata_ehi_push_desc(ehi, "ACPI event");

		ata_ehi_hotplugged(ehi);
		ata_port_freeze(