Merge branch 'fixes' of git://git.infradead.org/users/vkoul/slave-dma

Pull slave-dmaengine fixes from Vinod Koul:
 "We have two small fixes.  First one from Daniel to handle 0-length
  packets for usb cppi dma.  Second by Russell for imx-sdam cyclic
  residue reporting"

* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
  Update imx-sdma cyclic handling to report residue
  dma: cppi41: handle 0-length packets

2 files changed, 28 insertions, 7 deletions

diff --git a/drivers/dma/cppi41.c b/drivers/dma/cppi41.c
index d028f36ae655..8f8b0b608875 100644
--- a/drivers/dma/cppi41.c
+++ b/drivers/dma/cppi41.c
@@ -86,6 +86,9 @@
 
 #define USBSS_IRQ_PD_COMP	(1 <<  2)
 
+/* Packet Descriptor */
+#define PD2_ZERO_LENGTH		(1 << 19)
+
 struct cppi41_channel {
 	struct dma_chan chan;
 	struct dma_async_tx_descriptor txd;
@@ -307,7 +310,7 @@ static irqreturn_t cppi41_irq(int irq, void *data)
 			__iormb();
 
 		while (val) {
-			u32 desc;
+			u32 desc, len;
 
 			q_num = __fls(val);
 			val &= ~(1 << q_num);
@@ -319,9 +322,13 @@ static irqreturn_t cppi41_irq(int irq, void *data)
 						q_num, desc);
 				continue;
 			}
-			c->residue = pd_trans_len(c->desc->pd6) -
-				pd_trans_len(c->desc->pd0);
 
+			if (c->desc->pd2 & PD2_ZERO_LENGTH)
+				len = 0;
+			else
+				len = pd_trans_len(c->desc->pd0);
+
+			c->residue = pd_trans_len(c->desc->pd6) - len;
 			dma_cookie_complete(&c->txd);
 			c->txd.callback(c->txd.callback_param);
 		}
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 128714622bf5..14867e3ac8ff 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -255,6 +255,7 @@ struct sdma_channel {
 	enum dma_slave_buswidth		word_size;
 	unsigned int			buf_tail;
 	unsigned int			num_bd;
+	unsigned int			period_len;
 	struct sdma_buffer_descriptor	*bd;
 	dma_addr_t			bd_phys;
 	unsigned int			pc_from_device, pc_to_device;
@@ -593,6 +594,12 @@ static void sdma_event_disable(struct sdma_channel *sdmac, unsigned int event)
 
 static void sdma_handle_channel_loop(struct sdma_channel *sdmac)
 {
+	if (sdmac->desc.callback)
+		sdmac->desc.callback(sdmac->desc.callback_param);
+}
+
+static void sdma_update_channel_loop(struct sdma_channel *sdmac)
+{
 	struct sdma_buffer_descriptor *bd;
 
 	/*
@@ -611,9 +618,6 @@ static void sdma_handle_channel_loop(struct sdma_channel *sdmac)
 		bd->mode.status |= BD_DONE;
 		sdmac->buf_tail++;
 		sdmac->buf_tail %= sdmac->num_bd;
-
-		if (sdmac->desc.callback)
-			sdmac->desc.callback(sdmac->desc.callback_param);
 	}
 }
 
@@ -669,6 +673,9 @@ static irqreturn_t sdma_int_handler(int irq, void *dev_id)
 		int channel = fls(stat) - 1;
 		struct sdma_channel *sdmac = &sdma->channel[channel];
 
+		if (sdmac->flags & IMX_DMA_SG_LOOP)
+			sdma_update_channel_loop(sdmac);
+
 		tasklet_schedule(&sdmac->tasklet);
 
 		__clear_bit(channel, &stat);
@@ -1129,6 +1136,7 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
 	sdmac->status = DMA_IN_PROGRESS;
 
 	sdmac->buf_tail = 0;
+	sdmac->period_len = period_len;
 
 	sdmac->flags |= IMX_DMA_SG_LOOP;
 	sdmac->direction = direction;
@@ -1225,9 +1233,15 @@ static enum dma_status sdma_tx_status(struct dma_chan *chan,
 				      struct dma_tx_state *txstate)
 {
 	struct sdma_channel *sdmac = to_sdma_chan(chan);
+	u32 residue;
+
+	if (sdmac->flags & IMX_DMA_SG_LOOP)
+		residue = (sdmac->num_bd - sdmac->buf_tail) * sdmac->period_len;
+	else
+		residue = sdmac->chn_count - sdmac->chn_real_count;
 
 	dma_set_tx_state(txstate, chan->completed_cookie, chan->cookie,
-			sdmac->chn_count - sdmac->chn_real_count);
+			 residue);
 
 	return sdmac->status;
 }