ARM: OMAP4+: Have _omap4_wait_target_* check for valid clkctrl_offs

Previously the low-level CM call internal to the
_omap4_wait_target_ready/disable calls was responsible for checking for
a valid clkctrl_offs. Now we must also consider the value of the
prcm.omap4.flags because if HWMOD_OMAP4_ZERO_CLKCTRL_OFFSET is set in
the flags then clkctrl_offs of 0 is valid.

Let's add this check into the _omap4_wait_target_ready/disable where we
have access to both the clkctrl_offs and the flags values and simply
return 0 without calling the low level CM call at all, which would have
returned 0 anyway if the clktrl_offs was zero.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/omap_hwmod.c

@@ -1053,6 +1053,10 @@ static int _omap4_wait_target_disable(struct omap_hwmod *oh)
 	if (oh->flags & HWMOD_NO_IDLEST)
 		return 0;
 
+	if (!oh->prcm.omap4.clkctrl_offs &&
+	    !(oh->prcm.omap4.flags & HWMOD_OMAP4_ZERO_CLKCTRL_OFFSET))
+		return 0;
+
 	return omap_cm_wait_module_idle(oh->clkdm->prcm_partition,
 					oh->clkdm->cm_inst,
 					oh->prcm.omap4.clkctrl_offs, 0);
@@ -2971,6 +2975,10 @@ static int _omap4_wait_target_ready(struct omap_hwmod *oh)
 	if (!_find_mpu_rt_port(oh))
 		return 0;
 
+	if (!oh->prcm.omap4.clkctrl_offs &&
+	    !(oh->prcm.omap4.flags & HWMOD_OMAP4_ZERO_CLKCTRL_OFFSET))
+		return 0;
+
 	/* XXX check module SIDLEMODE, hardreset status */
 
 	return omap_cm_wait_module_ready(oh->clkdm->prcm_partition,