[PATCH 2/3] ARM: OMAP: hwmod: revise deassert sequence

From: Omar Ramirez Luna
Date: Mon Jul 16 2012 - 15:21:58 EST


For a reset sequence to complete cleanly, a module needs its
associated clocks to be enabled, otherwise the timeout check
in prcm code can print a false failure (failed to hardreset)
that occurs because the clocks aren't powered ON and the status
bit checked can't transition without them.

Signed-off-by: Omar Ramirez Luna <omar.luna@xxxxxxxxxx>
---
arch/arm/mach-omap2/omap_hwmod.c | 33 +++++++++++++++++++++++++++++++++
1 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 091c199..f6f8d99 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -1509,6 +1509,7 @@ static int _deassert_hardreset(struct omap_hwmod *oh, const char *name)
{
struct omap_hwmod_rst_info ohri;
int ret = -EINVAL;
+ int hwsup = 0;

if (!oh)
return -EINVAL;
@@ -1520,10 +1521,42 @@ static int _deassert_hardreset(struct omap_hwmod *oh, const char *name)
if (IS_ERR_VALUE(ret))
return ret;

+ if (oh->clkdm) {
+ /*
+ * A clockdomain must be in SW_SUP otherwise reset
+ * might not be completed. The clockdomain can be set
+ * in HW_AUTO only when the module become ready.
+ */
+ hwsup = clkdm_in_hwsup(oh->clkdm);
+ ret = clkdm_hwmod_enable(oh->clkdm, oh);
+ if (ret) {
+ WARN(1, "omap_hwmod: %s: could not enable clockdomain %s: %d\n",
+ oh->name, oh->clkdm->name, ret);
+ return ret;
+ }
+ }
+
+ _enable_clocks(oh);
+
ret = soc_ops.deassert_hardreset(oh, &ohri);
+
+ _disable_clocks(oh);
+
if (ret == -EBUSY)
pr_warning("omap_hwmod: %s: failed to hardreset\n", oh->name);

+ if (!ret) {
+ /*
+ * Set the clockdomain to HW_AUTO, assuming that the
+ * previous state was HW_AUTO.
+ */
+ if (oh->clkdm && hwsup)
+ clkdm_allow_idle(oh->clkdm);
+ } else {
+ if (oh->clkdm)
+ clkdm_hwmod_disable(oh->clkdm, oh);
+ }
+
return ret;
}

--
1.7.4.1

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