static void ab8500_charger_usb_link_status_work()

in supply/ab8500_charger.c [2280:2408]

• 100 lines of code
• 15 McCabe index (conditional complexity)

static void ab8500_charger_usb_link_status_work(struct work_struct *work)
{
	int detected_chargers;
	int ret;
	u8 val;
	u8 link_status;

	struct ab8500_charger *di = container_of(work,
		struct ab8500_charger, usb_link_status_work);

	/*
	 * Since we can't be sure that the events are received
	 * synchronously, we have the check if  is
	 * connected by reading the status register
	 */
	detected_chargers = ab8500_charger_detect_chargers(di, false);
	if (detected_chargers < 0)
		return;

	/*
	 * Some chargers that breaks the USB spec is
	 * identified as invalid by AB8500 and it refuse
	 * to start the charging process. but by jumping
	 * through a few hoops it can be forced to start.
	 */
	if (is_ab8500(di->parent))
		ret = abx500_get_register_interruptible(di->dev, AB8500_USB,
					AB8500_USB_LINE_STAT_REG, &val);
	else
		ret = abx500_get_register_interruptible(di->dev, AB8500_USB,
					AB8500_USB_LINK1_STAT_REG, &val);

	if (ret >= 0)
		dev_dbg(di->dev, "UsbLineStatus register = 0x%02x\n", val);
	else
		dev_dbg(di->dev, "Error reading USB link status\n");

	if (is_ab8500(di->parent))
		link_status = AB8500_USB_LINK_STATUS;
	else
		link_status = AB8505_USB_LINK_STATUS;

	if (detected_chargers & USB_PW_CONN) {
		if (((val & link_status) >> USB_LINK_STATUS_SHIFT) ==
				USB_STAT_NOT_VALID_LINK &&
				di->invalid_charger_detect_state == 0) {
			dev_dbg(di->dev,
					"Invalid charger detected, state= 0\n");
			/*Enable charger*/
			abx500_mask_and_set_register_interruptible(di->dev,
					AB8500_CHARGER, AB8500_USBCH_CTRL1_REG,
					USB_CH_ENA, USB_CH_ENA);
			/*Enable charger detection*/
			abx500_mask_and_set_register_interruptible(di->dev,
					AB8500_USB, AB8500_USB_LINE_CTRL2_REG,
					USB_CH_DET, USB_CH_DET);
			di->invalid_charger_detect_state = 1;
			/*exit and wait for new link status interrupt.*/
			return;

		}
		if (di->invalid_charger_detect_state == 1) {
			dev_dbg(di->dev,
					"Invalid charger detected, state= 1\n");
			/*Stop charger detection*/
			abx500_mask_and_set_register_interruptible(di->dev,
					AB8500_USB, AB8500_USB_LINE_CTRL2_REG,
					USB_CH_DET, 0x00);
			/*Check link status*/
			if (is_ab8500(di->parent))
				ret = abx500_get_register_interruptible(di->dev,
					AB8500_USB, AB8500_USB_LINE_STAT_REG,
					&val);
			else
				ret = abx500_get_register_interruptible(di->dev,
					AB8500_USB, AB8500_USB_LINK1_STAT_REG,
					&val);

			dev_dbg(di->dev, "USB link status= 0x%02x\n",
				(val & link_status) >> USB_LINK_STATUS_SHIFT);
			di->invalid_charger_detect_state = 2;
		}
	} else {
		di->invalid_charger_detect_state = 0;
	}

	if (!(detected_chargers & USB_PW_CONN)) {
		di->vbus_detected = false;
		ab8500_charger_set_usb_connected(di, false);
		ab8500_power_supply_changed(di, di->usb_chg.psy);
		return;
	}

	dev_dbg(di->dev,"%s di->vbus_detected = true\n",__func__);
	di->vbus_detected = true;
	ret = ab8500_charger_read_usb_type(di);
	if (ret) {
		if (ret == -ENXIO) {
			/* No valid charger type detected */
			ab8500_charger_set_usb_connected(di, false);
			ab8500_power_supply_changed(di, di->usb_chg.psy);
		}
		return;
	}

	if (di->usb_device_is_unrecognised) {
		dev_dbg(di->dev,
			"Potential Legacy Charger device. "
			"Delay work for %d msec for USB enum "
			"to finish",
			WAIT_ACA_RID_ENUMERATION);
		queue_delayed_work(di->charger_wq,
				   &di->attach_work,
				   msecs_to_jiffies(WAIT_ACA_RID_ENUMERATION));
	} else if (di->is_aca_rid == 1) {
		/* Only wait once */
		di->is_aca_rid++;
		dev_dbg(di->dev,
			"%s Wait %d msec for USB enum to finish",
			__func__, WAIT_ACA_RID_ENUMERATION);
		queue_delayed_work(di->charger_wq,
				   &di->attach_work,
				   msecs_to_jiffies(WAIT_ACA_RID_ENUMERATION));
	} else {
		queue_delayed_work(di->charger_wq,
				   &di->attach_work,
				   0);
	}
}