[3.19.y-ckt stable] Patch "ARM: OMAP2+: hwmod: Fix updating of sysconfig register" has been added to the 3.19.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    ARM: OMAP2+: hwmod: Fix updating of sysconfig register

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt20.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From 2f4a26ac8db4667ce19e71a8ac7568e46be8f3c2 Mon Sep 17 00:00:00 2001
From: Lokesh Vutla <lokeshvutla at ti.com>
Date: Sat, 26 Mar 2016 23:08:55 -0600
Subject: ARM: OMAP2+: hwmod: Fix updating of sysconfig register

commit 3ca4a238106dedc285193ee47f494a6584b6fd2f upstream.

Commit 127500ccb766f ("ARM: OMAP2+: Only write the sysconfig on idle
when necessary") talks about verification of sysconfig cache value before
updating it, only during idle path. But the patch is adding the
verification in the enable path. So, adding the check in a proper place
as per the commit description.

Not keeping this check during enable path as there is a chance of losing
context and it is safe to do on idle as the context of the register will
never be lost while the device is active.

Signed-off-by: Lokesh Vutla <lokeshvutla at ti.com>
Acked-by: Tero Kristo <t-kristo at ti.com>
Cc: Jon Hunter <jonathanh at nvidia.com>
Fixes: commit 127500ccb766 "ARM: OMAP2+: Only write the sysconfig on idle when necessary"
[paul at pwsan.com: appears to have been caused by my own mismerge of the
 originally posted patch]
Signed-off-by: Paul Walmsley <paul at pwsan.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 arch/arm/mach-omap2/omap_hwmod.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index c692451..c5f3942 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -1390,9 +1390,7 @@ static void _enable_sysc(struct omap_hwmod *oh)
 	    (sf & SYSC_HAS_CLOCKACTIVITY))
 		_set_clockactivity(oh, oh->class->sysc->clockact, &v);

-	/* If the cached value is the same as the new value, skip the write */
-	if (oh->_sysc_cache != v)
-		_write_sysconfig(v, oh);
+	_write_sysconfig(v, oh);

 	/*
 	 * Set the autoidle bit only after setting the smartidle bit
@@ -1455,7 +1453,9 @@ static void _idle_sysc(struct omap_hwmod *oh)
 		_set_master_standbymode(oh, idlemode, &v);
 	}

-	_write_sysconfig(v, oh);
+	/* If the cached value is the same as the new value, skip the write */
+	if (oh->_sysc_cache != v)
+		_write_sysconfig(v, oh);
 }

 /**
--
2.7.4