TWL4030: Force power down before powering up the PHY
To address issues with USB not enumerating properly when the cable
is connected on a warm reboot, make sure the PHY is powered down
before powering it up. This results in proper enumeration on a
warm reboot.
Change-Id: If52df6386ec7c8bd3c6715b96644e1dad752b9a7
diff --git a/drivers/usb/phy/twl4030.c b/drivers/usb/phy/twl4030.c
index 54d2e61..6dcf6c9 100644
--- a/drivers/usb/phy/twl4030.c
+++ b/drivers/usb/phy/twl4030.c
@@ -118,10 +118,22 @@
{
u8 pwr, clk;
- /* Power the PHY */
+ /* First make sure PHY is powered down to
+ * clear any state from a previous reboot and
+ * force unenumeration. Otherwise, sometimes
+ * the device doesn't enumerate properly on
+ * a warm reboot.
+ */
+
+ /* Power down the PHY */
pwr = twl4030_usb_read(TWL4030_USB_PHY_PWR_CTRL);
+ pwr |= PHYPWD;
+ twl4030_usb_write(TWL4030_USB_PHY_PWR_CTRL, pwr);
+
+ /* Power the PHY */
pwr &= ~PHYPWD;
twl4030_usb_write(TWL4030_USB_PHY_PWR_CTRL, pwr);
+
/* Enable clocks */
clk = twl4030_usb_read(TWL4030_USB_PHY_CLK_CTRL);
clk |= CLOCKGATING_EN | CLK32K_EN;
@@ -139,6 +151,8 @@
long timeout = 1000 * 1000; /* 1 sec */;
u8 clk, sts, pwr;
+ i2c_set_bus_num(0);
+
/* twl4030 ldo init */
twl4030_usb_ldo_init();
