ARM: OMAP2+: hwmod: add parent_hwmod support

Add parent_hwmod pointer to omap_hwmod. This can be set to point to a
"parent" hwmod that needs to be enabled for the "child" hwmod to work.

This is used at hwmod setup time: when doing the initial setup and
reset, first enable the parent hwmod, and after setup and reset is done,
restore the parent hwmod to postsetup_state.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Archit Taneja <archit.taneja@gmail.com>
[paul@pwsan.com: add kerneldoc documentation for parent_hwmod; note that it
 is a temporary workaround]
Signed-off-by: Paul Walmsley <paul@pwsan.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index acae6d5d1151..a2c7b300fe89 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -2719,11 +2719,33 @@ static int __init _setup(struct omap_hwmod *oh, void *data)
 	if (oh->_state != _HWMOD_STATE_INITIALIZED)
 		return 0;
 
+	if (oh->parent_hwmod) {
+		int r;
+
+		r = _enable(oh->parent_hwmod);
+		WARN(r, "hwmod: %s: setup: failed to enable parent hwmod %s\n",
+		     oh->name, oh->parent_hwmod->name);
+	}
+
 	_setup_iclk_autoidle(oh);
 
 	if (!_setup_reset(oh))
 		_setup_postsetup(oh);
 
+	if (oh->parent_hwmod) {
+		u8 postsetup_state;
+
+		postsetup_state = oh->parent_hwmod->_postsetup_state;
+
+		if (postsetup_state == _HWMOD_STATE_IDLE)
+			_idle(oh->parent_hwmod);
+		else if (postsetup_state == _HWMOD_STATE_DISABLED)
+			_shutdown(oh->parent_hwmod);
+		else if (postsetup_state != _HWMOD_STATE_ENABLED)
+			WARN(1, "hwmod: %s: unknown postsetup state %d! defaulting to enabled\n",
+			     oh->parent_hwmod->name, postsetup_state);
+	}
+
 	return 0;
 }