1 files changed, 33 insertions, 25 deletions

diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
index 88aad4f..b4588bd 100644
--- a/drivers/dma/mxs-dma.c
+++ b/drivers/dma/mxs-dma.c
@@ -130,6 +130,23 @@ struct mxs_dma_engine {
 	struct mxs_dma_chan		mxs_chans[MXS_DMA_CHANNELS];
 };
 
+static inline void mxs_dma_clkgate(struct mxs_dma_chan *mxs_chan, int enable)
+{
+	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
+	int chan_id = mxs_chan->chan.chan_id;
+	int set_clr = enable ? MXS_CLR_ADDR : MXS_SET_ADDR;
+
+	/* enable apbh channel clock */
+	if (dma_is_apbh()) {
+		if (apbh_is_old())
+			writel(1 << (chan_id + BP_APBH_CTRL0_CLKGATE_CHANNEL),
+				mxs_dma->base + HW_APBHX_CTRL0 + set_clr);
+		else
+			writel(1 << chan_id,
+				mxs_dma->base + HW_APBHX_CTRL0 + set_clr);
+	}
+}
+
 static void mxs_dma_reset_chan(struct mxs_dma_chan *mxs_chan)
 {
 	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
@@ -148,38 +165,21 @@ static void mxs_dma_enable_chan(struct mxs_dma_chan *mxs_chan)
 	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
 	int chan_id = mxs_chan->chan.chan_id;
 
+	/* clkgate needs to be enabled before writing other registers */
+	mxs_dma_clkgate(mxs_chan, 1);
+
 	/* set cmd_addr up */
 	writel(mxs_chan->ccw_phys,
 		mxs_dma->base + HW_APBHX_CHn_NXTCMDAR(chan_id));
 
-	/* enable apbh channel clock */
-	if (dma_is_apbh()) {
-		if (apbh_is_old())
-			writel(1 << (chan_id + BP_APBH_CTRL0_CLKGATE_CHANNEL),
-				mxs_dma->base + HW_APBHX_CTRL0 + MXS_CLR_ADDR);
-		else
-			writel(1 << chan_id,
-				mxs_dma->base + HW_APBHX_CTRL0 + MXS_CLR_ADDR);
-	}
-
 	/* write 1 to SEMA to kick off the channel */
 	writel(1, mxs_dma->base + HW_APBHX_CHn_SEMA(chan_id));
 }
 
 static void mxs_dma_disable_chan(struct mxs_dma_chan *mxs_chan)
 {
-	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
-	int chan_id = mxs_chan->chan.chan_id;
-
 	/* disable apbh channel clock */
-	if (dma_is_apbh()) {
-		if (apbh_is_old())
-			writel(1 << (chan_id + BP_APBH_CTRL0_CLKGATE_CHANNEL),
-				mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
-		else
-			writel(1 << chan_id,
-				mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
-	}
+	mxs_dma_clkgate(mxs_chan, 0);
 
 	mxs_chan->status = DMA_SUCCESS;
 }
@@ -327,16 +327,21 @@ static int mxs_dma_alloc_chan_resources(struct dma_chan *chan)
 
 	memset(mxs_chan->ccw, 0, PAGE_SIZE);
 
-	ret = request_irq(mxs_chan->chan_irq, mxs_dma_int_handler,
-				0, "mxs-dma", mxs_dma);
-	if (ret)
-		goto err_irq;
+	if (mxs_chan->chan_irq != NO_IRQ) {
+		ret = request_irq(mxs_chan->chan_irq, mxs_dma_int_handler,
+					0, "mxs-dma", mxs_dma);
+		if (ret)
+			goto err_irq;
+	}
 
 	ret = clk_enable(mxs_dma->clk);
 	if (ret)
 		goto err_clk;
 
+	/* clkgate needs to be enabled for reset to finish */
+	mxs_dma_clkgate(mxs_chan, 1);
 	mxs_dma_reset_chan(mxs_chan);
+	mxs_dma_clkgate(mxs_chan, 0);
 
 	dma_async_tx_descriptor_init(&mxs_chan->desc, chan);
 	mxs_chan->desc.tx_submit = mxs_dma_tx_submit;
@@ -535,6 +540,7 @@ static int mxs_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
 	switch (cmd) {
 	case DMA_TERMINATE_ALL:
 		mxs_dma_disable_chan(mxs_chan);
+		mxs_dma_reset_chan(mxs_chan);
 		break;
 	case DMA_PAUSE:
 		mxs_dma_pause_chan(mxs_chan);
@@ -707,6 +713,8 @@ static struct platform_device_id mxs_dma_type[] = {
 	}, {
 		.name = "mxs-dma-apbx",
 		.driver_data = MXS_DMA_APBX,
+	}, {
+		/* end of list */
 	}
 };