dma: mxs-dma: make mxs_dma_prep_slave_sg() multi user safe
Using a static variable for counting the number of CCWs attached to
a DMA channel when appending a new descriptor is not multi user safe.
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
index b0e6ac3..1b4c6be 100644
--- a/drivers/dma/mxs-dma.c
+++ b/drivers/dma/mxs-dma.c
@@ -111,6 +111,7 @@
int chan_irq;
struct mxs_dma_ccw *ccw;
dma_addr_t ccw_phys;
+ int desc_count;
dma_cookie_t last_completed;
enum dma_status status;
unsigned int flags;
@@ -386,7 +387,7 @@
struct scatterlist *sg;
int i, j;
u32 *pio;
- static int idx;
+ int idx = append ? mxs_chan->desc_count : 0;
if (mxs_chan->status == DMA_IN_PROGRESS && !append)
return NULL;
@@ -462,6 +463,7 @@
}
}
}
+ mxs_chan->desc_count = idx;
return &mxs_chan->desc;
@@ -523,6 +525,7 @@
i++;
}
+ mxs_chan->desc_count = i;
return &mxs_chan->desc;