[Qemu-devel] [PATCH 2/3] Fixes two bugs with the Stelaris ADC.

[Logan Gunthorpe <logang@ece.ualberta.ca>]

- The adc gets double-triggered because the stelaris_adc_trigger function
  does not ignore calls when the level is low.
- In the stelaris_adc_fifo_read function there is a slight bug that fails
  to set the empty flag when the tail pointer overflows back to zero.
---
 hw/stellaris.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/hw/stellaris.c b/hw/stellaris.c
index 5f44bff..4fadeec 100644
--- a/hw/stellaris.c
+++ b/hw/stellaris.c
@@ -934,7 +934,7 @@ static uint32_t stellaris_adc_fifo_read(stellaris_adc_state *s, int n)
     } else {
         s->fifo[n].state = (s->fifo[n].state & ~0xf) | ((tail + 1) & 0xf);
         s->fifo[n].state &= ~STELLARIS_ADC_FIFO_FULL;
-        if (tail + 1 == ((s->fifo[n].state >> 4) & 0xf))
+        if (((tail + 1) & 0xf) == ((s->fifo[n].state >> 4) & 0xf))
             s->fifo[n].state |= STELLARIS_ADC_FIFO_EMPTY;
     }
     return s->fifo[n].data[tail];
@@ -976,6 +976,8 @@ static void stellaris_adc_trigger(void *opaque, int irq, int level)
     stellaris_adc_state *s = (stellaris_adc_state *)opaque;
     int n;
 
+    if (!level) return;
+
     for (n = 0; n < 4; n++) {
         if ((s->actss & (1 << n)) == 0) {
             continue;
-- 
1.5.6.5