DMA: PL330: move filter function into driver

The dma channel selection filter function is moved from plat-samsung
into the pl330 driver. In additon to that, a check is added in the
filter function to ensure that the channel on which the filter has
been invoked is pl330 channel instance (and avoid any incorrect
access of chan->private in a system with multiple types of DMA
drivers).

Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 571041477ab2..0c434dca4bf2 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -116,6 +116,9 @@ struct dma_pl330_desc {
 	struct dma_pl330_chan *pchan;
 };
 
+/* forward declaration */
+static struct amba_driver pl330_driver;
+
 static inline struct dma_pl330_chan *
 to_pchan(struct dma_chan *ch)
 {
@@ -267,6 +270,18 @@ static void dma_pl330_rqcb(void *token, enum pl330_op_err err)
 	tasklet_schedule(&pch->task);
 }
 
+bool pl330_filter(struct dma_chan *chan, void *param)
+{
+	struct dma_pl330_peri *peri;
+
+	if (chan->device->dev->driver != &pl330_driver.drv)
+		return false;
+
+	peri = chan->private;
+	return peri->peri_id == (unsigned)param;
+}
+EXPORT_SYMBOL(pl330_filter);
+
 static int pl330_alloc_chan_resources(struct dma_chan *chan)
 {
 	struct dma_pl330_chan *pch = to_pchan(chan);