usb: chipidea: coordinate usb phy initialization for different phy type
authorPeter Chen <peter.chen@freescale.com>
Wed, 23 Apr 2014 07:56:37 +0000 (15:56 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 24 Apr 2014 19:56:34 +0000 (12:56 -0700)
For internal PHY (like UTMI), the phy clock may from internal pll,
it is on/off on the fly, the access PORTSC.PTS will hang without
phy clock. So, the usb_phy_init which will open phy clock needs to
be called before hw_phymode_configure.
See: http://marc.info/?l=linux-arm-kernel&m=139350618732108&w=2

For external PHY (like ulpi), it needs to configure portsc.pts before
visit viewport, or the viewport can't be visited. so phy_phymode_configure
needs to be called before usb_phy_init.
See: cd0b42c2a6d2a74244f0053f8960f5dad5842278

It may not the best solution, but it can work for all situations.

Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Cc: shc_work@mail.ru
Cc: denis@eukrea.com
Cc: festevam@gmail.com
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/chipidea/core.c

index ca6831c5b763053d146d8c7bbae2f10d85e3c3d1..1cd5d0ba587c8ebaf49c876a086570be4cabd8c9 100644 (file)
@@ -276,6 +276,39 @@ static void hw_phymode_configure(struct ci_hdrc *ci)
        }
 }
 
+/**
+ * ci_usb_phy_init: initialize phy according to different phy type
+ * @ci: the controller
+  *
+ * This function returns an error code if usb_phy_init has failed
+ */
+static int ci_usb_phy_init(struct ci_hdrc *ci)
+{
+       int ret;
+
+       switch (ci->platdata->phy_mode) {
+       case USBPHY_INTERFACE_MODE_UTMI:
+       case USBPHY_INTERFACE_MODE_UTMIW:
+       case USBPHY_INTERFACE_MODE_HSIC:
+               ret = usb_phy_init(ci->transceiver);
+               if (ret)
+                       return ret;
+               hw_phymode_configure(ci);
+               break;
+       case USBPHY_INTERFACE_MODE_ULPI:
+       case USBPHY_INTERFACE_MODE_SERIAL:
+               hw_phymode_configure(ci);
+               ret = usb_phy_init(ci->transceiver);
+               if (ret)
+                       return ret;
+               break;
+       default:
+               ret = usb_phy_init(ci->transceiver);
+       }
+
+       return ret;
+}
+
 /**
  * hw_device_reset: resets chip (execute without interruption)
  * @ci: the controller
@@ -543,8 +576,6 @@ static int ci_hdrc_probe(struct platform_device *pdev)
                return -ENODEV;
        }
 
-       hw_phymode_configure(ci);
-
        if (ci->platdata->phy)
                ci->transceiver = ci->platdata->phy;
        else
@@ -564,7 +595,7 @@ static int ci_hdrc_probe(struct platform_device *pdev)
                return -EPROBE_DEFER;
        }
 
-       ret = usb_phy_init(ci->transceiver);
+       ret = ci_usb_phy_init(ci);
        if (ret) {
                dev_err(dev, "unable to init phy: %d\n", ret);
                return ret;