[RFC: PATCH] New API to modify the autoidle bits of sysconfig register

[Kishon Vijay Abraham I <kishon@ti.com>]

Though the sysconfig register values shouldn't be modified directly by
the driver, MCBSP should be considered a special case where sysconfig
registers need to be modified dynamically by the driver.

For e.g MCBSP 2 and 3 in OMAP3 has sidetone feature which requires
autoidle to be disabled before starting the sidetone.

This patch creates a new API that forms a wrapper to
_set_module_autoidle() to modify the AUTOIDLE bit.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Charulatha V <charu@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>

Cc: Paul Walmsley<paul@pwsan.com>
Cc: Benoit Cousson<b-cousson@ti.com>
Cc: Partha Basak <p-basak2@ti.com>

---
 arch/arm/mach-omap2/omap_hwmod.c             |   29 ++++++++++++++++++++++++++
 arch/arm/plat-omap/include/plat/omap_hwmod.h |    1 +
 2 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 9bd99ad..0d38404 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -969,6 +969,35 @@ int _omap_hwmod_idle(struct omap_hwmod *oh)
 }
 
 /**
+ * omap_hwmod_set_module_autoidle - set the hwmod's OCP slave autoidle
+ * @oh: struct omap_hwmod *
+ * @autoidle: desired AUTOIDLE bitfield value (0 or 1)
+ *
+ * Sets the IP block's OCP slave autoidle in hardware, and updates our
+ * local copy. Intended to be used by drivers that have some erratum
+ * that requires direct manipulation of the AUTOIDLE bits.  Returns
+ * -EINVAL if @oh is null, or passes along the return value from
+ * _set_module_autoidle().
+ */
+int omap_hwmod_set_module_autoidle(struct omap_hwmod *oh, u8 autoidle)
+{
+	u32 v;
+	int retval = 0;
+
+	if (!oh)
+		return -EINVAL;
+
+	v = oh->_sysc_cache;
+
+	retval = _set_module_autoidle(oh, autoidle, &v);
+
+	if (!retval)
+		_write_sysconfig(v, oh);
+
+	return retval;
+}
+
+/**
  * _shutdown - shutdown an omap_hwmod
  * @oh: struct omap_hwmod *
  *
diff --git a/arch/arm/plat-omap/include/plat/omap_hwmod.h b/arch/arm/plat-omap/include/plat/omap_hwmod.h
index 6adbb63..7042b86 100644
--- a/arch/arm/plat-omap/include/plat/omap_hwmod.h
+++ b/arch/arm/plat-omap/include/plat/omap_hwmod.h
@@ -526,6 +526,7 @@ int omap_hwmod_hardreset_deassert(struct omap_hwmod *oh, const char *name);
 int omap_hwmod_hardreset_state(struct omap_hwmod *oh, const char *name);
 
 int omap_hwmod_set_slave_idlemode(struct omap_hwmod *oh, u8 idlemode);
+int omap_hwmod_set_module_autoidle(struct omap_hwmod *oh, u8 autoidle)
 
 int omap_hwmod_reset(struct omap_hwmod *oh);
 void omap_hwmod_ocp_barrier(struct omap_hwmod *oh);
-- 
1.7.0.4