ARM: OMAP2+ hwmod: Allow modules to disable HW_AUTO

Introduce HWMOD_CLKDM_NOAUTO flag that allows the hwmod's
clockdomain to be prevented from HW_AUTO while the hwmod is active.

This is needed to workaround some modules which don't function
correctly with HW_AUTO. e.g. DCAN on DRA7.

Signed-off-by: Roger Quadros <rogerq@ti.com>
[nsekhar@ti.com: rebased to v4.9 kernel]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 8a40393..8bcea0d 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -2027,7 +2027,7 @@ static int _enable(struct omap_hwmod *oh)
 
 	r = (soc_ops.wait_target_ready) ? soc_ops.wait_target_ready(oh) :
 		-EINVAL;
-	if (oh->clkdm)
+	if (oh->clkdm && !(oh->flags & HWMOD_CLKDM_NOAUTO))
 		clkdm_allow_idle(oh->clkdm);
 
 	if (!r) {
@@ -2084,7 +2084,12 @@ static int _idle(struct omap_hwmod *oh)
 		_idle_sysc(oh);
 	_del_initiator_dep(oh, mpu_oh);
 
-	if (oh->clkdm)
+	/*
+	 * If HWMOD_CLKDM_NOAUTO is set then we don't
+	 * deny idle the clkdm again since idle was already denied
+	 * in _enable()
+	 */
+	if (oh->clkdm && !(oh->flags & HWMOD_CLKDM_NOAUTO))
 		clkdm_deny_idle(oh->clkdm);
 
 	if (oh->flags & HWMOD_BLOCK_WFI)