Merge tag 'fix-v3.17-io-chain-v3' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Regression fix for early omap3 revisions for wake-up events that
too some time to narrow down. Although a bit intrusive, this would
be good to get into the -rc cycle as there are quite a few boards
out there with omap3 es2.1 and es3.0, and we have those in at least
three boot test systems too that show errors without this patch.

* tag 'fix-v3.17-io-chain-v3' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: OMAP3: Fix I/O chain clock line assertion timed out error

Signed-off-by: Olof Johansson <olof@lixom.net>

2 files changed, 36 insertions, 5 deletions

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 8fd87a3055bf..9e91a4e7519a 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -2065,7 +2065,7 @@ static void _reconfigure_io_chain(void)
 
         spin_lock_irqsave(&io_chain_lock, flags);
 
-        if (cpu_is_omap34xx() && omap3_has_io_chain_ctrl())
+        if (cpu_is_omap34xx())
                 omap3xxx_prm_reconfigure_io_chain();
         else if (cpu_is_omap44xx())
                 omap44xx_prm_reconfigure_io_chain();
diff --git a/arch/arm/mach-omap2/prm3xxx.c b/arch/arm/mach-omap2/prm3xxx.c
index 2458be6fc67b..372de3edf4a5 100644
--- a/arch/arm/mach-omap2/prm3xxx.c
+++ b/arch/arm/mach-omap2/prm3xxx.c
@@ -45,7 +45,7 @@ static struct omap_prcm_irq_setup omap3_prcm_irq_setup = {
         .ocp_barrier            = &omap3xxx_prm_ocp_barrier,
         .save_and_clear_irqen   = &omap3xxx_prm_save_and_clear_irqen,
         .restore_irqen          = &omap3xxx_prm_restore_irqen,
-        .reconfigure_io_chain   = &omap3xxx_prm_reconfigure_io_chain,
+        .reconfigure_io_chain   = NULL,
 };
 
 /*
@@ -369,15 +369,30 @@ void __init omap3_prm_init_pm(bool has_uart4, bool has_iva)
 }
 
 /**
- * omap3xxx_prm_reconfigure_io_chain - clear latches and reconfigure I/O chain
+ * omap3430_pre_es3_1_reconfigure_io_chain - restart wake-up daisy chain
+ *
+ * The ST_IO_CHAIN bit does not exist in 3430 before es3.1. The only
+ * thing we can do is toggle EN_IO bit for earlier omaps.
+ */
+void omap3430_pre_es3_1_reconfigure_io_chain(void)
+{
+        omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD,
+                                     PM_WKEN);
+        omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD,
+                                   PM_WKEN);
+        omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
+}
+
+/**
+ * omap3_prm_reconfigure_io_chain - clear latches and reconfigure I/O chain
  *
  * Clear any previously-latched I/O wakeup events and ensure that the
  * I/O wakeup gates are aligned with the current mux settings.  Works
  * by asserting WUCLKIN, waiting for WUCLKOUT to be asserted, and then
  * deasserting WUCLKIN and clearing the ST_IO_CHAIN WKST bit.  No
- * return value.
+ * return value. These registers are only available in 3430 es3.1 and later.
  */
-void omap3xxx_prm_reconfigure_io_chain(void)
+void omap3_prm_reconfigure_io_chain(void)
 {
         int i = 0;
 
@@ -400,6 +415,15 @@ void omap3xxx_prm_reconfigure_io_chain(void)
 }
 
 /**
+ * omap3xxx_prm_reconfigure_io_chain - reconfigure I/O chain
+ */
+void omap3xxx_prm_reconfigure_io_chain(void)
+{
+        if (omap3_prcm_irq_setup.reconfigure_io_chain)
+                omap3_prcm_irq_setup.reconfigure_io_chain();
+}
+
+/**
  * omap3xxx_prm_enable_io_wakeup - enable wakeup events from I/O wakeup latches
  *
  * Activates the I/O wakeup event latches and allows events logged by
@@ -656,6 +680,13 @@ static int omap3xxx_prm_late_init(void)
         if (!(prm_features & PRM_HAS_IO_WAKEUP))
                 return 0;
 
+        if (omap3_has_io_chain_ctrl())
+                omap3_prcm_irq_setup.reconfigure_io_chain =
+                        omap3_prm_reconfigure_io_chain;
+        else
+                omap3_prcm_irq_setup.reconfigure_io_chain =
+                        omap3430_pre_es3_1_reconfigure_io_chain;
+
         omap3xxx_prm_enable_io_wakeup();
         ret = omap_prcm_register_chain_handler(&omap3_prcm_irq_setup);
         if (!ret)