musb_hdrc: Keep tusb osc_ck enabled during idle even in OTG mode

In OTG mode VBUS draw mA can be 8mA which can be less than
musb->min_power. When connected as OTG device, tusb does not
keep osc_ck enabled without this patch.
Signed-off-by: Tony Lindgren <tony@atomide.com>

drivers/usb/musb/tusb6010.c

@@ -273,6 +273,16 @@ static int tusb_draw_power(struct otg_transceiver *x, unsigned mA)
 	void __iomem	*base = musb->ctrl_base;
 	u32		reg;
 
+	/*
+	 * Keep clock active when enabled. Note that this is not tied to
+	 * drawing VBUS, as with OTG mA can be less than musb->min_power.
+	 */
+	if (musb->set_clock)
+		if (mA)
+			musb->set_clock(musb->clock, 1);
+		else
+			musb->set_clock(musb->clock, 0);
+
 	/* tps65030 seems to consume max 100mA, with maybe 60mA available
 	 * (measured on one board) for things other than tps and tusb.
 	 *
@@ -288,15 +298,11 @@ static int tusb_draw_power(struct otg_transceiver *x, unsigned mA)
 
 	reg = musb_readl(base, TUSB_PRCM_MNGMT);
 	if (mA) {
-		if (musb->set_clock)
-			musb->set_clock(musb->clock, 1);
 		musb->is_bus_powered = 1;
 		reg |= TUSB_PRCM_MNGMT_15_SW_EN | TUSB_PRCM_MNGMT_33_SW_EN;
 	} else {
 		musb->is_bus_powered = 0;
 		reg &= ~(TUSB_PRCM_MNGMT_15_SW_EN | TUSB_PRCM_MNGMT_33_SW_EN);
-		if (musb->set_clock)
-			musb->set_clock(musb->clock, 0);
 	}
 	musb_writel(base, TUSB_PRCM_MNGMT, reg);