bus.c

linux 内核源代码

	 * Make sure this device's parent is present before we go about
	 * messing with the device.
	 */
	if (device->parent && !device->parent->status.present) {
		device->status = device->parent->status;
		if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
			if (status_changed)
				*status_changed = 1;
		}
		return 0;
	}

	status = acpi_bus_get_status(device);
	if (ACPI_FAILURE(status))
		return -ENODEV;

	if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
		return 0;

	if (status_changed)
		*status_changed = 1;

	/*
	 * Device Insertion/Removal
	 */
	if ((device->status.present) && !(old_status.present)) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
		/* TBD: Handle device insertion */
	} else if (!(device->status.present) && (old_status.present)) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
		/* TBD: Handle device removal */
	}

	return 0;
}

static int acpi_bus_check_scope(struct acpi_device *device)
{
	int result = 0;
	int status_changed = 0;


	if (!device)
		return -EINVAL;

	/* Status Change? */
	result = acpi_bus_check_device(device, &status_changed);
	if (result)
		return result;

	if (!status_changed)
		return 0;

	/*
	 * TBD: Enumerate child devices within this device's scope and
	 *       run acpi_bus_check_device()'s on them.
	 */

	return 0;
}

/**
 * acpi_bus_notify
 * ---------------
 * Callback for all 'system-level' device notifications (values 0x00-0x7F).
 */
static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
{
	int result = 0;
	struct acpi_device *device = NULL;


	if (acpi_bus_get_device(handle, &device))
		return;

	switch (type) {

	case ACPI_NOTIFY_BUS_CHECK:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Received BUS CHECK notification for device [%s]\n",
				  device->pnp.bus_id));
		result = acpi_bus_check_scope(device);
		/*
		 * TBD: We'll need to outsource certain events to non-ACPI
		 *      drivers via the device manager (device.c).
		 */
		break;

	case ACPI_NOTIFY_DEVICE_CHECK:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Received DEVICE CHECK notification for device [%s]\n",
				  device->pnp.bus_id));
		result = acpi_bus_check_device(device, NULL);
		/*
		 * TBD: We'll need to outsource certain events to non-ACPI
		 *      drivers via the device manager (device.c).
		 */
		break;

	case ACPI_NOTIFY_DEVICE_WAKE:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Received DEVICE WAKE notification for device [%s]\n",
				  device->pnp.bus_id));
		/* TBD */
		break;

	case ACPI_NOTIFY_EJECT_REQUEST:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Received EJECT REQUEST notification for device [%s]\n",
				  device->pnp.bus_id));
		/* TBD */
		break;

	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Received DEVICE CHECK LIGHT notification for device [%s]\n",
				  device->pnp.bus_id));
		/* TBD: Exactly what does 'light' mean? */
		break;

	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Received FREQUENCY MISMATCH notification for device [%s]\n",
				  device->pnp.bus_id));
		/* TBD */
		break;

	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Received BUS MODE MISMATCH notification for device [%s]\n",
				  device->pnp.bus_id));
		/* TBD */
		break;

	case ACPI_NOTIFY_POWER_FAULT:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Received POWER FAULT notification for device [%s]\n",
				  device->pnp.bus_id));
		/* TBD */
		break;

	default:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Received unknown/unsupported notification [%08x]\n",
				  type));
		break;
	}

	return;
}

/* --------------------------------------------------------------------------
                             Initialization/Cleanup
   -------------------------------------------------------------------------- */

static int __init acpi_bus_init_irq(void)
{
	acpi_status status = AE_OK;
	union acpi_object arg = { ACPI_TYPE_INTEGER };
	struct acpi_object_list arg_list = { 1, &arg };
	char *message = NULL;


	/*
	 * Let the system know what interrupt model we are using by
	 * evaluating the \_PIC object, if exists.
	 */

	switch (acpi_irq_model) {
	case ACPI_IRQ_MODEL_PIC:
		message = "PIC";
		break;
	case ACPI_IRQ_MODEL_IOAPIC:
		message = "IOAPIC";
		break;
	case ACPI_IRQ_MODEL_IOSAPIC:
		message = "IOSAPIC";
		break;
	case ACPI_IRQ_MODEL_PLATFORM:
		message = "platform specific model";
		break;
	default:
		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
		return -ENODEV;
	}

	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);

	arg.integer.value = acpi_irq_model;

	status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
		return -ENODEV;
	}

	return 0;
}

acpi_native_uint acpi_gbl_permanent_mmap;


void __init acpi_early_init(void)
{
	acpi_status status = AE_OK;

	if (acpi_disabled)
		return;

	printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);

	/* enable workarounds, unless strict ACPI spec. compliance */
	if (!acpi_strict)
		acpi_gbl_enable_interpreter_slack = TRUE;

	acpi_gbl_permanent_mmap = 1;

	status = acpi_reallocate_root_table();
	if (ACPI_FAILURE(status)) {
		printk(KERN_ERR PREFIX
		       "Unable to reallocate ACPI tables\n");
		goto error0;
	}

	status = acpi_initialize_subsystem();
	if (ACPI_FAILURE(status)) {
		printk(KERN_ERR PREFIX
		       "Unable to initialize the ACPI Interpreter\n");
		goto error0;
	}

	status = acpi_load_tables();
	if (ACPI_FAILURE(status)) {
		printk(KERN_ERR PREFIX
		       "Unable to load the System Description Tables\n");
		goto error0;
	}

#ifdef CONFIG_X86
	if (!acpi_ioapic) {
		extern u8 acpi_sci_flags;

		/* compatible (0) means level (3) */
		if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
			acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
			acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
		}
		/* Set PIC-mode SCI trigger type */
		acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
					 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
	} else {
		extern int acpi_sci_override_gsi;
		/*
		 * now that acpi_gbl_FADT is initialized,
		 * update it with result from INT_SRC_OVR parsing
		 */
		acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
	}
#endif

	status =
	    acpi_enable_subsystem(~
				  (ACPI_NO_HARDWARE_INIT |
				   ACPI_NO_ACPI_ENABLE));
	if (ACPI_FAILURE(status)) {
		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
		goto error0;
	}

	return;

      error0:
	disable_acpi();
	return;
}

static int __init acpi_bus_init(void)
{
	int result = 0;
	acpi_status status = AE_OK;
	extern acpi_status acpi_os_initialize1(void);


	status = acpi_os_initialize1();

	status =
	    acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
	if (ACPI_FAILURE(status)) {
		printk(KERN_ERR PREFIX
		       "Unable to start the ACPI Interpreter\n");
		goto error1;
	}

	if (ACPI_FAILURE(status)) {
		printk(KERN_ERR PREFIX
		       "Unable to initialize ACPI OS objects\n");
		goto error1;
	}
#ifdef CONFIG_ACPI_EC
	/*
	 * ACPI 2.0 requires the EC driver to be loaded and work before
	 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
	 * is called).
	 *
	 * This is accomplished by looking for the ECDT table, and getting
	 * the EC parameters out of that.
	 */
	status = acpi_ec_ecdt_probe();
	/* Ignore result. Not having an ECDT is not fatal. */
#endif

	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
	if (ACPI_FAILURE(status)) {
		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
		goto error1;
	}

	printk(KERN_INFO PREFIX "Interpreter enabled\n");

	/* Initialize sleep structures */
	acpi_sleep_init();

	/*
	 * Get the system interrupt model and evaluate \_PIC.
	 */
	result = acpi_bus_init_irq();
	if (result)
		goto error1;

	/*
	 * Register the for all standard device notifications.
	 */
	status =
	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
					&acpi_bus_notify, NULL);
	if (ACPI_FAILURE(status)) {
		printk(KERN_ERR PREFIX
		       "Unable to register for device notifications\n");
		goto error1;
	}

	/*
	 * Create the top ACPI proc directory
	 */
	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);

	return 0;

	/* Mimic structured exception handling */
      error1:
	acpi_terminate();
	return -ENODEV;
}

decl_subsys(acpi, NULL, NULL);

static int __init acpi_init(void)
{
	int result = 0;


	if (acpi_disabled) {
		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
		return -ENODEV;
	}

	result = firmware_register(&acpi_subsys);
	if (result < 0)
		printk(KERN_WARNING "%s: firmware_register error: %d\n",
			__FUNCTION__, result);

	result = acpi_bus_init();

	if (!result) {
		if (!(pm_flags & PM_APM))
			pm_flags |= PM_ACPI;
		else {
			printk(KERN_INFO PREFIX
			       "APM is already active, exiting\n");
			disable_acpi();
			result = -ENODEV;
		}
	} else
		disable_acpi();

	return result;
}

subsys_initcall(acpi_init);