mfd: ab8500-core: Ignore masked out interrupts

AB8500 asserts LATCH bits for masked out interrupts.  This patch
explicitly masks those out using the cached mask value to prevent
handle_nested_irq() being called for masked IRQ on the same register as
unmasked ones.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Fabio Baltieri <fabio.baltieri@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 14 insertions, 13 deletions

diff --git a/drivers/mfd/ab8500-core.c b/drivers/mfd/ab8500-core.c
index f276352cc9ef..36751f37dd52 100644
--- a/drivers/mfd/ab8500-core.c
+++ b/drivers/mfd/ab8500-core.c
@@ -458,22 +458,23 @@ static void update_latch_offset(u8 *offset, int i)
 static int ab8500_handle_hierarchical_line(struct ab8500 *ab8500,
                                         int latch_offset, u8 latch_val)
 {
-        int int_bit = __ffs(latch_val);
-        int line, i;
+        int int_bit, line, i;
 
-        do {
-                int_bit = __ffs(latch_val);
+        for (i = 0; i < ab8500->mask_size; i++)
+                if (ab8500->irq_reg_offset[i] == latch_offset)
+                        break;
 
-                for (i = 0; i < ab8500->mask_size; i++)
-                        if (ab8500->irq_reg_offset[i] == latch_offset)
-                                break;
+        if (i >= ab8500->mask_size) {
+                dev_err(ab8500->dev, "Register offset 0x%2x not declared\n",
+                                latch_offset);
+                return -ENXIO;
+        }
 
-                if (i >= ab8500->mask_size) {
-                        dev_err(ab8500->dev, "Register offset 0x%2x not declared\n",
-                                        latch_offset);
-                        return -ENXIO;
-                }
+        /* ignore masked out interrupts */
+        latch_val &= ~ab8500->mask[i];
 
+        while (latch_val) {
+                int_bit = __ffs(latch_val);
                 line = (i << 3) + int_bit;
                 latch_val &= ~(1 << int_bit);
 
@@ -491,7 +492,7 @@ static int ab8500_handle_hierarchical_line(struct ab8500 *ab8500,
                         line += 1;
 
                 handle_nested_irq(ab8500->irq_base + line);
-        } while (latch_val);
+        }
 
         return 0;
 }