C++ power_down函数代码示例

static int ov2680_s_config(struct v4l2_subdev *sd,
			   int irq, void *platform_data)
{
	struct ov2680_device *dev = to_ov2680_sensor(sd);
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	int ret = 0;

	if (!platform_data)
		return -ENODEV;

	dev->platform_data =
		(struct camera_sensor_platform_data *)platform_data;

	mutex_lock(&dev->input_lock);
	/* power off the module, then power on it in future
	 * as first power on by board may not fulfill the
	 * power on sequqence needed by the module
	 */
	ret = power_down(sd);
	if (ret) {
		dev_err(&client->dev, "ov2680 power-off err.\n");
		goto fail_power_off;
	}

	ret = power_up(sd);
	if (ret) {
		dev_err(&client->dev, "ov2680 power-up err.\n");
		goto fail_power_on;
	}

	ret = dev->platform_data->csi_cfg(sd, 1);
	if (ret)
		goto fail_csi_cfg;

	/* config & detect sensor */
	ret = ov2680_detect(client);
	if (ret) {
		dev_err(&client->dev, "ov2680_detect err s_config.\n");
		goto fail_csi_cfg;
	}

	/* turn off sensor, after probed */
	ret = power_down(sd);
	if (ret) {
		dev_err(&client->dev, "ov2680 power-off err.\n");
		goto fail_csi_cfg;
	}
	mutex_unlock(&dev->input_lock);

	return 0;

fail_csi_cfg:
	dev->platform_data->csi_cfg(sd, 0);
fail_power_on:
	power_down(sd);
	dev_err(&client->dev, "sensor power-gating failed\n");
fail_power_off:
	mutex_unlock(&dev->input_lock);
	return ret;
}

static int ov5693_s_config(struct v4l2_subdev *sd,
			   int irq, void *platform_data)
{
	struct ov5693_device *dev = to_ov5693_sensor(sd);
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	int ret = 0;

	if (platform_data == NULL)
		return -ENODEV;

	mutex_lock(&dev->input_lock);

	dev->platform_data = platform_data;

	ret = power_up(sd);
	if (ret) {
		dev_err(&client->dev, "ov5693 power-up err.\n");
		goto fail_power_on;
	}

	ret = dev->platform_data->csi_cfg(sd, 1);
	if (ret)
		goto fail_csi_cfg;

	/* config & detect sensor */
	ret = ov5693_detect(client);
	if (ret) {
		dev_err(&client->dev, "ov5693_detect err s_config.\n");
		goto fail_csi_cfg;
	}

	/* turn off sensor, after probed */
	ret = power_down(sd);
	if (ret) {
		dev_err(&client->dev, "ov5693 power-off err.\n");
		goto fail_csi_cfg;
	}
	mutex_unlock(&dev->input_lock);

	return 0;

fail_csi_cfg:
	dev->platform_data->csi_cfg(sd, 0);
fail_power_on:
	power_down(sd);
	dev_err(&client->dev, "sensor power-gating failed\n");
	mutex_unlock(&dev->input_lock);
	return ret;
}

static int
isp1301_set_peripheral(struct otg_transceiver *otg, struct usb_gadget *gadget)
{
	struct isp1301	*isp = container_of(otg, struct isp1301, otg);

	if (!otg || isp != the_transceiver)
		return -ENODEV;

	if (!gadget) {
		OTG_IRQ_EN_REG = 0;
		if (!isp->otg.default_a)
			enable_vbus_draw(isp, 0);
		usb_gadget_vbus_disconnect(isp->otg.gadget);
		isp->otg.gadget = 0;
		power_down(isp);
		return 0;
	}

#ifdef	CONFIG_USB_OTG
	isp->otg.gadget = gadget;
	dev_dbg(&isp->client.dev, "registered gadget\n");
	/* gadget driver may be suspended until vbus_connect () */
	if (isp->otg.host)
		return isp1301_otg_enable(isp);
	return 0;

#elif	!defined(CONFIG_USB_OHCI_HCD) && !defined(CONFIG_USB_OHCI_HCD_MODULE)
	isp->otg.gadget = gadget;
	// FIXME update its refcount

	OTG_CTRL_REG = (OTG_CTRL_REG & OTG_CTRL_MASK
				& ~(OTG_XCEIV_OUTPUTS|OTG_CTRL_BITS))
			| OTG_ID;
	power_up(isp);
	isp->otg.state = OTG_STATE_B_IDLE;

	if (machine_is_omap_h2())
		isp1301_set_bits(isp, ISP1301_MODE_CONTROL_1, MC1_DAT_SE0);

	isp1301_set_bits(isp, ISP1301_INTERRUPT_RISING,
		INTR_SESS_VLD);
	isp1301_set_bits(isp, ISP1301_INTERRUPT_FALLING,
		INTR_VBUS_VLD);
	dev_info(&isp->client.dev, "B-Peripheral sessions ok\n");
	dump_regs(isp, __func__);

	/* If this has a Mini-AB connector, this mode is highly
	 * nonstandard ... but can be handy for testing, so long
	 * as you don't plug a Mini-A cable into the jack.
	 */
	if (isp1301_get_u8(isp, ISP1301_INTERRUPT_SOURCE) & INTR_VBUS_VLD)
		b_peripheral(isp);

	return 0;

#else
	dev_dbg(&isp->client.dev, "peripheral sessions not allowed\n");
	return -EINVAL;
#endif
}

static int ov5693_s_power(struct v4l2_subdev *sd, int on)
{
	struct ov5693_device *dev = to_ov5693_sensor(sd);
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	int ret = 0;

	mutex_lock(&dev->input_lock);
	if (on == 0) {
		if (dev->vcm_driver && dev->vcm_driver->power_down)
			ret = dev->vcm_driver->power_down(sd);
		if (ret)
			dev_err(&client->dev, "vcm power-down failed.\n");

		ret = power_down(sd);
	} else {
		ret = power_up(sd);
		if (ret)
			goto done;

		ret = ov5693_init(sd);
		if (ret)
			goto done;

		if (dev->vcm_driver && dev->vcm_driver->power_up)
			ret = dev->vcm_driver->power_up(sd);
		if (ret)
			dev_err(&client->dev, "vcm power-up failed.\n");
	}

done:
	mutex_unlock(&dev->input_lock);
	return ret;
}

int pm_suspend_disk(void)
{
	int error;

	if ((error = prepare()))
		return error;

	pr_debug("PM: Attempting to suspend to disk.\n");
	if (pm_disk_mode == PM_DISK_FIRMWARE)
		return pm_ops->enter(PM_SUSPEND_DISK);

	pr_debug("PM: snapshotting memory.\n");
	in_suspend = 1;
	if ((error = swsusp_suspend()))
		goto Done;

	if (in_suspend) {
		pr_debug("PM: writing image.\n");
		error = swsusp_write();
		if (!error)
			power_down(pm_disk_mode);
	} else
		pr_debug("PM: Image restored successfully.\n");
	swsusp_free();
 Done:
	finish();
	return error;
}

int hibernate(void)
{
	int error;

	mutex_lock(&pm_mutex);
	/* The snapshot device should not be opened while we're running */
	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
		error = -EBUSY;
		goto Unlock;
	}

	error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
	if (error)
		goto Exit;

	/* Allocate memory management structures */
	error = create_basic_memory_bitmaps();
	if (error)
		goto Exit;

	printk("Syncing filesystems ... ");
	sys_sync();
	printk("done.\n");

	error = prepare_processes();
	if (error)
		goto Finish;

	if (hibernation_mode == HIBERNATION_TESTPROC) {
		printk("swsusp debug: Waiting for 5 seconds.\n");
		mdelay(5000);
		goto Thaw;
	}
	error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
	if (in_suspend && !error) {
		unsigned int flags = 0;

		if (hibernation_mode == HIBERNATION_PLATFORM)
			flags |= SF_PLATFORM_MODE;
		pr_debug("PM: writing image.\n");
		error = swsusp_write(flags);
		swsusp_free();
		if (!error)
			power_down();
	} else {
		pr_debug("PM: Image restored successfully.\n");
		swsusp_free();
	}
 Thaw:
	unprepare_processes();
 Finish:
	free_basic_memory_bitmaps();
 Exit:
	pm_notifier_call_chain(PM_POST_HIBERNATION);
	atomic_inc(&snapshot_device_available);
 Unlock:
	mutex_unlock(&pm_mutex);
	return error;
}

void
quit(void)
{
    if (buffer != NULL)
	free(buffer);
    power_down();
    exit(1);
}

void
read_chip(void)
{
    int             r;

    power_up();
    r = chips[chipindex].read_func(buffersize, pagesize);
    file_save(); 
    power_down();
}

/* add or disable the host device+driver */
static int
isp1301_set_host(struct otg_transceiver *otg, struct usb_bus *host)
{
	struct isp1301	*isp = container_of(otg, struct isp1301, otg);

	if (!otg || isp != the_transceiver)
		return -ENODEV;

	if (!host) {
		omap_writew(0, OTG_IRQ_EN);
		power_down(isp);
		isp->otg.host = NULL;
		return 0;
	}

#ifdef	CONFIG_USB_OTG
	isp->otg.host = host;
	dev_dbg(&isp->client->dev, "registered host\n");
	host_suspend(isp);
	if (isp->otg.gadget)
		return isp1301_otg_enable(isp);
	return 0;

#elif	!defined(CONFIG_USB_GADGET_OMAP)
	// FIXME update its refcount
	isp->otg.host = host;

	power_up(isp);

	if (machine_is_omap_h2())
		isp1301_set_bits(isp, ISP1301_MODE_CONTROL_1, MC1_DAT_SE0);

	dev_info(&isp->client->dev, "A-Host sessions ok\n");
	isp1301_set_bits(isp, ISP1301_INTERRUPT_RISING,
		INTR_ID_GND);
	isp1301_set_bits(isp, ISP1301_INTERRUPT_FALLING,
		INTR_ID_GND);

	/* If this has a Mini-AB connector, this mode is highly
	 * nonstandard ... but can be handy for testing, especially with
	 * the Mini-A end of an OTG cable.  (Or something nonstandard
	 * like MiniB-to-StandardB, maybe built with a gender mender.)
	 */
	isp1301_set_bits(isp, ISP1301_OTG_CONTROL_1, OTG1_VBUS_DRV);

	dump_regs(isp, __func__);

	return 0;

#else
	dev_dbg(&isp->client->dev, "host sessions not allowed\n");
	return -EINVAL;
#endif

}

int
probe_chip (void)
{

  int i;
  power_up ();
  for (i = 0; chips[i].name != NULL; i++)
    {
      chips[i].probe_func();
      if ((chips[i].id1 == id1) && (chips[i].id2 == id2))
	{
          chipindex = i;
          chip_selected ();
	  power_down ();
	  return 1;
	};
    };
  chipindex = i - 1;
  power_down ();
  return -1;
}

int pm_suspend_disk(void)
{
	int error;

	error = prepare_processes();
	if (error)
		return error;

	if (pm_disk_mode == PM_DISK_TESTPROC)
		return 0;

	suspend_console();
	error = device_suspend(PMSG_FREEZE);
	if (error) {
		resume_console();
		printk("Some devices failed to suspend\n");
		goto Thaw;
	}

	if (pm_disk_mode == PM_DISK_TEST) {
		printk("swsusp debug: Waiting for 5 seconds.\n");
		mdelay(5000);
		goto Done;
	}

	pr_debug("PM: snapshotting memory.\n");
	in_suspend = 1;
	if ((error = swsusp_suspend()))
		goto Done;

	if (in_suspend) {
		device_resume();
		resume_console();
		pr_debug("PM: writing image.\n");
		error = swsusp_write();
		if (!error)
			power_down(pm_disk_mode);
		else {
			swsusp_free();
			goto Thaw;
		}
	} else {
		pr_debug("PM: Image restored successfully.\n");
	}

	swsusp_free();
 Done:
	device_resume();
	resume_console();
 Thaw:
	unprepare_processes();
	return error;
}

static int ov2680_s_power(struct v4l2_subdev *sd, int on)
{
	int ret;

	if (on == 0){
		ret = power_down(sd);
	} else {
		ret = power_up(sd);
		if (!ret)
			return ov2680_init(sd);
	}
	return ret;
}

int main(uint32_t arg, uint32_t *result_id)
{
    switch(boot_decision(get_context()))
    {
        case BOOT_ROCK:
            *result_id = arg;
            return BOOT_ROM_SECTION;
        case BOOT_OF:
            return BOOT_ROM_CONTINUE;
        case BOOT_STOP:
        default:
            power_down();
    }
}

void suspend_power_down(void)
{
#ifdef NO_SUSPEND_POWER_DOWN
    ;
#elif defined(SUSPEND_MODE_NOPOWERSAVE)
    ;
#elif defined(SUSPEND_MODE_STANDBY)
    standby();
#elif defined(SUSPEND_MODE_IDLE)
    idle();
#else
    power_down(WDTO_15MS);
#endif
}

void
erase_chip(void)
{

    int             r,
                    b;

    power_up();
    r = chips[chipindex].erase_func(buffersize, pagesize);
    b = generic_blank_check(buffersize, pagesize);
    power_down();

    if (r < 0 || b < 0)
	msg_error();

}