usb: dwc_otg_310: pcd: fix force device mode issue

When tested usb device through force device mode method,
we found that usb device failed to connect to usb host
in the following case.

1. Use micro usb 2.0 OTG interface.
2. Plug in otg cable, and the id pin was pulled down
   to Ground.
3. User space force usb to enter device mode through
   'echo 2 > /sys/bus/platform/drivers/usb20_otg/force_usb_mode'
4. Use usb 2.0 Standard-A to Standard-A cable assembly,
   plug into otg cable receptor on one side, and connect
   to PC on the other side.
5. PC fail to enumerate our device, because of usb driver
   logical issue.

This is because that the dwc_otg_pcd_check_vbus_work()
only enable usb to start connecting if check the bvalid
and iddig is high. But in the above test case, the iddig
is low, so fail to start connection work. In this patch,
we enable usb to connect if iddig is high or usb is in
force device mode.

In addition, fix some coding style to increase the readability.

Change-Id: I08f1a4e6e7e5fb246b1716a20d4572d8b866f238
Signed-off-by: William Wu <william.wu@rock-chips.com>

diff --git a/drivers/usb/dwc_otg_310/dwc_otg_pcd_linux.c b/drivers/usb/dwc_otg_310/dwc_otg_pcd_linux.c
index 203d3c93fa1f06e55bba044bb74fd06aaef51969..631579722ab091bc9c9ea7ff4f3f0015b165ca10 100644 (file)
--- a/drivers/usb/dwc_otg_310/dwc_otg_pcd_linux.c
+++ b/drivers/usb/dwc_otg_310/dwc_otg_pcd_linux.c
@@ -1636,21 +1636,25 @@ static void dwc_otg_pcd_check_vbus_work(struct work_struct *work)
            container_of(work, dwc_otg_pcd_t, check_vbus_work.work);
        struct dwc_otg_device *otg_dev = _pcd->otg_dev;
        struct dwc_otg_platform_data *pldata = otg_dev->pldata;
+       int bvalid = pldata->get_status(USB_STATUS_BVABLID);
+       int iddig = pldata->get_status(USB_STATUS_ID);
+       u8 usb_mode = otg_dev->core_if->usb_mode;
 
-       if (pldata->get_status(USB_STATUS_BVABLID) &&
-           pldata->get_status(USB_STATUS_ID)) {
-               /* if usb not connect before ,then start connect */
+       if (bvalid && (iddig || (usb_mode == USB_MODE_FORCE_DEVICE))) {
+               /* If usb not connect before, then start connect */
                if (_pcd->vbus_status == USB_BC_TYPE_DISCNT) {
                        printk("***************vbus detect*****************\n");
-                       if( pldata->bc_detect_cb != NULL )
-                               pldata->bc_detect_cb(_pcd->vbus_status =
-                                       usb_battery_charger_detect(1));
+
+                       if (pldata->bc_detect_cb && iddig)
+                               pldata->bc_detect_cb(_pcd->vbus_status =
+                                       usb_battery_charger_detect(1));
                        else
                                _pcd->vbus_status = USB_BC_TYPE_SDP;
+
                        if (_pcd->conn_en) {
                                goto connect;
                        } else if (pldata->phy_status == USB_PHY_ENABLED) {
-                               /* do not allow to connect, suspend phy */
+                               /* Do not allow to connect, suspend phy */
                                pldata->phy_suspend(pldata, USB_PHY_SUSPEND);
                                udelay(3);
                                pldata->clock_enable(pldata, 0);
@@ -1660,18 +1664,21 @@ static void dwc_otg_pcd_check_vbus_work(struct work_struct *work)
                        printk("**************soft reconnect**************\n");
                        goto connect;
                } else if (_pcd->conn_status == 2) {
-                       /* release pcd->wake_lock if fail to connect,
-                        * allow system to enter second sleep.
+                       /*
+                        * Release pcd->wake_lock if fail to connect,
+                        * and allow system to enter deep sleep.
                         */
                        dwc_otg_msc_unlock(_pcd);
                        _pcd->conn_status++;
-                       if (pldata->bc_detect_cb != NULL) {
+
+                       if (pldata->bc_detect_cb && iddig) {
                                pldata->bc_detect_cb(_pcd->vbus_status =
                                                     usb_battery_charger_detect(1));
                        } else {
                                _pcd->vbus_status = USB_BC_TYPE_DCP;
                        }
-                       /* fail to connect, suspend usb phy and disable clk */
+
+                       /* Fail to connect, suspend usb phy and disable clk */
                        if (pldata->phy_status == USB_PHY_ENABLED) {
                                pldata->phy_suspend(pldata, USB_PHY_SUSPEND);
                                udelay(3);
@@ -1679,7 +1686,7 @@ static void dwc_otg_pcd_check_vbus_work(struct work_struct *work)
                        }
                }
        } else {
-               if (pldata->bc_detect_cb != NULL)
+               if (pldata->bc_detect_cb && iddig)
                        pldata->bc_detect_cb(_pcd->vbus_status =
                                             usb_battery_charger_detect(0));
                else
@@ -1690,22 +1697,23 @@ static void dwc_otg_pcd_check_vbus_work(struct work_struct *work)
                }
 
                if (pldata->phy_status == USB_PHY_ENABLED) {
-                       /* release wake lock */
+                       /* Release wake lock */
                        dwc_otg_msc_unlock(_pcd);
-                       if (pldata->get_status(USB_STATUS_ID)) {
-                               /* no vbus detect here , close usb phy  */
+
+                       if (iddig || (usb_mode == USB_MODE_FORCE_DEVICE)) {
+                               /* No vbus detect here , suspend usb phy */
                                pldata->phy_suspend(pldata, USB_PHY_SUSPEND);
                                udelay(3);
                                pldata->clock_enable(pldata, 0);
                        }
                }
 
-               /* usb phy bypass to uart mode  */
+               /* Bypass usb phy to uart mode  */
                if (pldata->dwc_otg_uart_mode != NULL)
                        pldata->dwc_otg_uart_mode(pldata, PHY_UART_MODE);
        }
 
-       if (pldata->get_status(USB_STATUS_ID))
+       if (iddig || (usb_mode == USB_MODE_FORCE_DEVICE))
                schedule_delayed_work(&_pcd->check_vbus_work, HZ);
        return;
 
@@ -1718,8 +1726,9 @@ connect:
        if (_pcd->conn_status == 0)
                dwc_otg_msc_lock(_pcd);
 
-       schedule_delayed_work(&_pcd->reconnect, 8);     /* delay 8 jiffies */
+       schedule_delayed_work(&_pcd->reconnect, 8);
        schedule_delayed_work(&_pcd->check_vbus_work, (HZ));
+
        return;
 }