ARM: OMAP3: PM: Move IO Daisychain function to omap3 prm file

Since IO Daisychain modifies only PRM registers, it makes sense to move
it to PRM File. Also changed the timeout value for IO chain enable to
100us and added a wait for status disable at the end.

Thanks to Nishanth Menon <nm@ti.com> for contributing a fix to the
timeout code waiting for WUCLKOUT to go high.

Signed-off-by: Vishwanath BS <vishwanath.bs@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Reviewed-by: Rajendra Nayak <rnayak@ti.com>
[paul@pwsan.com: renamed omap3_trigger_io_chain() to better describe the
 end result and to match other PRM functions; removed
 omap3_disable_io_chain(); moved MAX_IOPAD_LATCH_TIME to prcm-common as it
 will also be used by the OMAP4 code; removed unnecessary barrier;
 added kerneldoc; added credit for fix from Nishanth]
Signed-off-by: Paul Walmsley <paul@pwsan.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/prcm-common.h b/arch/arm/mach-omap2/prcm-common.h
index 6da3ba483ad1..fca23cbea708 100644
--- a/arch/arm/mach-omap2/prcm-common.h
+++ b/arch/arm/mach-omap2/prcm-common.h
@@ -410,6 +410,14 @@
  */
 #define MAX_MODULE_HARDRESET_WAIT		10000
 
+/*
+ * Maximum time(us) it takes to output the signal WUCLKOUT of the last
+ * pad of the I/O ring after asserting WUCLKIN high.  Tero measured
+ * the actual time at 7 to 8 microseconds on OMAP3 and 2 to 4
+ * microseconds on OMAP4, so this timeout may be too high.
+ */
+#define MAX_IOPAD_LATCH_TIME			100
+
 # ifndef __ASSEMBLER__
 extern void __iomem *prm_base;
 extern void __iomem *cm_base;