ARM: OMAP: Add DMA IRQ sanity checks
Add DMA IRQ sanity checks
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
index f3f84fb..2d86b10 100644
--- a/arch/arm/plat-omap/dma.c
+++ b/arch/arm/plat-omap/dma.c
@@ -925,10 +925,17 @@
{
u32 status = OMAP_DMA_CSR_REG(ch);
- if (!status)
+ if (!status) {
+ if (printk_ratelimit())
+ printk(KERN_WARNING "Spurious DMA IRQ for lch %d\n", ch);
return 0;
- if (unlikely(dma_chan[ch].dev_id == -1))
+ }
+ if (unlikely(dma_chan[ch].dev_id == -1)) {
+ if (printk_ratelimit())
+ printk(KERN_WARNING "IRQ %04x for non-allocated DMA"
+ "channel %d\n", status, ch);
return 0;
+ }
if (unlikely(status & OMAP_DMA_DROP_IRQ))
printk(KERN_INFO
"DMA synchronization event drop occurred with device "
@@ -959,11 +966,15 @@
int i;
val = omap_readl(OMAP_DMA4_IRQSTATUS_L0);
-
- for (i = 1; i <= OMAP_LOGICAL_DMA_CH_COUNT; i++) {
- int active = val & (1 << (i - 1));
- if (active)
- omap2_dma_handle_ch(i - 1);
+ if (val == 0) {
+ if (printk_ratelimit())
+ printk(KERN_WARNING "Spurious DMA IRQ\n");
+ return IRQ_HANDLED;
+ }
+ for (i = 0; i < OMAP_LOGICAL_DMA_CH_COUNT && val != 0; i++) {
+ if (val & 1)
+ omap2_dma_handle_ch(i);
+ val >>= 1;
}
return IRQ_HANDLED;