summaryrefslogtreecommitdiffstats
path: root/drivers/dma/ep93xx_dma.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/dma/ep93xx_dma.c')
-rw-r--r--drivers/dma/ep93xx_dma.c90
1 files changed, 63 insertions, 27 deletions
diff --git a/drivers/dma/ep93xx_dma.c b/drivers/dma/ep93xx_dma.c
index b47e2b803fa..59e7a965772 100644
--- a/drivers/dma/ep93xx_dma.c
+++ b/drivers/dma/ep93xx_dma.c
@@ -246,6 +246,9 @@ static void ep93xx_dma_set_active(struct ep93xx_dma_chan *edmac,
static struct ep93xx_dma_desc *
ep93xx_dma_get_active(struct ep93xx_dma_chan *edmac)
{
+ if (list_empty(&edmac->active))
+ return NULL;
+
return list_first_entry(&edmac->active, struct ep93xx_dma_desc, node);
}
@@ -263,16 +266,22 @@ ep93xx_dma_get_active(struct ep93xx_dma_chan *edmac)
*/
static bool ep93xx_dma_advance_active(struct ep93xx_dma_chan *edmac)
{
+ struct ep93xx_dma_desc *desc;
+
list_rotate_left(&edmac->active);
if (test_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags))
return true;
+ desc = ep93xx_dma_get_active(edmac);
+ if (!desc)
+ return false;
+
/*
* If txd.cookie is set it means that we are back in the first
* descriptor in the chain and hence done with it.
*/
- return !ep93xx_dma_get_active(edmac)->txd.cookie;
+ return !desc->txd.cookie;
}
/*
@@ -327,10 +336,16 @@ static void m2p_hw_shutdown(struct ep93xx_dma_chan *edmac)
static void m2p_fill_desc(struct ep93xx_dma_chan *edmac)
{
- struct ep93xx_dma_desc *desc = ep93xx_dma_get_active(edmac);
+ struct ep93xx_dma_desc *desc;
u32 bus_addr;
- if (ep93xx_dma_chan_direction(&edmac->chan) == DMA_TO_DEVICE)
+ desc = ep93xx_dma_get_active(edmac);
+ if (!desc) {
+ dev_warn(chan2dev(edmac), "M2P: empty descriptor list\n");
+ return;
+ }
+
+ if (ep93xx_dma_chan_direction(&edmac->chan) == DMA_MEM_TO_DEV)
bus_addr = desc->src_addr;
else
bus_addr = desc->dst_addr;
@@ -443,7 +458,7 @@ static int m2m_hw_setup(struct ep93xx_dma_chan *edmac)
control = (5 << M2M_CONTROL_PWSC_SHIFT);
control |= M2M_CONTROL_NO_HDSK;
- if (data->direction == DMA_TO_DEVICE) {
+ if (data->direction == DMA_MEM_TO_DEV) {
control |= M2M_CONTROL_DAH;
control |= M2M_CONTROL_TM_TX;
control |= M2M_CONTROL_RSS_SSPTX;
@@ -459,11 +474,7 @@ static int m2m_hw_setup(struct ep93xx_dma_chan *edmac)
* This IDE part is totally untested. Values below are taken
* from the EP93xx Users's Guide and might not be correct.
*/
- control |= M2M_CONTROL_NO_HDSK;
- control |= M2M_CONTROL_RSS_IDE;
- control |= M2M_CONTROL_PW_16;
-
- if (data->direction == DMA_TO_DEVICE) {
+ if (data->direction == DMA_MEM_TO_DEV) {
/* Worst case from the UG */
control = (3 << M2M_CONTROL_PWSC_SHIFT);
control |= M2M_CONTROL_DAH;
@@ -473,6 +484,10 @@ static int m2m_hw_setup(struct ep93xx_dma_chan *edmac)
control |= M2M_CONTROL_SAH;
control |= M2M_CONTROL_TM_RX;
}
+
+ control |= M2M_CONTROL_NO_HDSK;
+ control |= M2M_CONTROL_RSS_IDE;
+ control |= M2M_CONTROL_PW_16;
break;
default:
@@ -491,7 +506,13 @@ static void m2m_hw_shutdown(struct ep93xx_dma_chan *edmac)
static void m2m_fill_desc(struct ep93xx_dma_chan *edmac)
{
- struct ep93xx_dma_desc *desc = ep93xx_dma_get_active(edmac);
+ struct ep93xx_dma_desc *desc;
+
+ desc = ep93xx_dma_get_active(edmac);
+ if (!desc) {
+ dev_warn(chan2dev(edmac), "M2M: empty descriptor list\n");
+ return;
+ }
if (edmac->buffer == 0) {
writel(desc->src_addr, edmac->regs + M2M_SAR_BASE0);
@@ -669,24 +690,30 @@ static void ep93xx_dma_tasklet(unsigned long data)
{
struct ep93xx_dma_chan *edmac = (struct ep93xx_dma_chan *)data;
struct ep93xx_dma_desc *desc, *d;
- dma_async_tx_callback callback;
- void *callback_param;
+ dma_async_tx_callback callback = NULL;
+ void *callback_param = NULL;
LIST_HEAD(list);
spin_lock_irq(&edmac->lock);
+ /*
+ * If dma_terminate_all() was called before we get to run, the active
+ * list has become empty. If that happens we aren't supposed to do
+ * anything more than call ep93xx_dma_advance_work().
+ */
desc = ep93xx_dma_get_active(edmac);
- if (desc->complete) {
- edmac->last_completed = desc->txd.cookie;
- list_splice_init(&edmac->active, &list);
+ if (desc) {
+ if (desc->complete) {
+ edmac->last_completed = desc->txd.cookie;
+ list_splice_init(&edmac->active, &list);
+ }
+ callback = desc->txd.callback;
+ callback_param = desc->txd.callback_param;
}
spin_unlock_irq(&edmac->lock);
/* Pick up the next descriptor from the queue */
ep93xx_dma_advance_work(edmac);
- callback = desc->txd.callback;
- callback_param = desc->txd.callback_param;
-
/* Now we can release all the chained descriptors */
list_for_each_entry_safe(desc, d, &list, node) {
/*
@@ -706,13 +733,22 @@ static void ep93xx_dma_tasklet(unsigned long data)
static irqreturn_t ep93xx_dma_interrupt(int irq, void *dev_id)
{
struct ep93xx_dma_chan *edmac = dev_id;
+ struct ep93xx_dma_desc *desc;
irqreturn_t ret = IRQ_HANDLED;
spin_lock(&edmac->lock);
+ desc = ep93xx_dma_get_active(edmac);
+ if (!desc) {
+ dev_warn(chan2dev(edmac),
+ "got interrupt while active list is empty\n");
+ spin_unlock(&edmac->lock);
+ return IRQ_NONE;
+ }
+
switch (edmac->edma->hw_interrupt(edmac)) {
case INTERRUPT_DONE:
- ep93xx_dma_get_active(edmac)->complete = true;
+ desc->complete = true;
tasklet_schedule(&edmac->tasklet);
break;
@@ -803,8 +839,8 @@ static int ep93xx_dma_alloc_chan_resources(struct dma_chan *chan)
switch (data->port) {
case EP93XX_DMA_SSP:
case EP93XX_DMA_IDE:
- if (data->direction != DMA_TO_DEVICE &&
- data->direction != DMA_FROM_DEVICE)
+ if (data->direction != DMA_MEM_TO_DEV &&
+ data->direction != DMA_DEV_TO_MEM)
return -EINVAL;
break;
default:
@@ -952,7 +988,7 @@ fail:
*/
static struct dma_async_tx_descriptor *
ep93xx_dma_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
- unsigned int sg_len, enum dma_data_direction dir,
+ unsigned int sg_len, enum dma_transfer_direction dir,
unsigned long flags)
{
struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan);
@@ -988,7 +1024,7 @@ ep93xx_dma_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
goto fail;
}
- if (dir == DMA_TO_DEVICE) {
+ if (dir == DMA_MEM_TO_DEV) {
desc->src_addr = sg_dma_address(sg);
desc->dst_addr = edmac->runtime_addr;
} else {
@@ -1032,7 +1068,7 @@ fail:
static struct dma_async_tx_descriptor *
ep93xx_dma_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t dma_addr,
size_t buf_len, size_t period_len,
- enum dma_data_direction dir)
+ enum dma_transfer_direction dir)
{
struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan);
struct ep93xx_dma_desc *desc, *first;
@@ -1065,7 +1101,7 @@ ep93xx_dma_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t dma_addr,
goto fail;
}
- if (dir == DMA_TO_DEVICE) {
+ if (dir == DMA_MEM_TO_DEV) {
desc->src_addr = dma_addr + offset;
desc->dst_addr = edmac->runtime_addr;
} else {
@@ -1133,12 +1169,12 @@ static int ep93xx_dma_slave_config(struct ep93xx_dma_chan *edmac,
return -EINVAL;
switch (config->direction) {
- case DMA_FROM_DEVICE:
+ case DMA_DEV_TO_MEM:
width = config->src_addr_width;
addr = config->src_addr;
break;
- case DMA_TO_DEVICE:
+ case DMA_MEM_TO_DEV:
width = config->dst_addr_width;
addr = config->dst_addr;
break;