rapidio: add new RapidIO DMA interface routines
Add RapidIO DMA interface routines that directly use reference to the mport
device object and/or target device destination ID as parameters.
This allows to perform RapidIO DMA transfer requests by modules that do not
have an access to the RapidIO device list.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Cc: Stef van Os <stef.van.os@prodrive-technologies.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rapidio/rio.c b/drivers/rapidio/rio.c
index a54ba04..d7b87c6 100644
--- a/drivers/rapidio/rio.c
+++ b/drivers/rapidio/rio.c
@@ -1509,30 +1509,39 @@
static bool rio_chan_filter(struct dma_chan *chan, void *arg)
{
- struct rio_dev *rdev = arg;
+ struct rio_mport *mport = arg;
/* Check that DMA device belongs to the right MPORT */
- return (rdev->net->hport ==
- container_of(chan->device, struct rio_mport, dma));
+ return mport == container_of(chan->device, struct rio_mport, dma);
}
/**
+ * rio_request_mport_dma - request RapidIO capable DMA channel associated
+ * with specified local RapidIO mport device.
+ * @mport: RIO mport to perform DMA data transfers
+ *
+ * Returns pointer to allocated DMA channel or NULL if failed.
+ */
+struct dma_chan *rio_request_mport_dma(struct rio_mport *mport)
+{
+ dma_cap_mask_t mask;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+ return dma_request_channel(mask, rio_chan_filter, mport);
+}
+EXPORT_SYMBOL_GPL(rio_request_mport_dma);
+
+/**
* rio_request_dma - request RapidIO capable DMA channel that supports
* specified target RapidIO device.
- * @rdev: RIO device control structure
+ * @rdev: RIO device associated with DMA transfer
*
* Returns pointer to allocated DMA channel or NULL if failed.
*/
struct dma_chan *rio_request_dma(struct rio_dev *rdev)
{
- dma_cap_mask_t mask;
- struct dma_chan *dchan;
-
- dma_cap_zero(mask);
- dma_cap_set(DMA_SLAVE, mask);
- dchan = dma_request_channel(mask, rio_chan_filter, rdev);
-
- return dchan;
+ return rio_request_mport_dma(rdev->net->hport);
}
EXPORT_SYMBOL_GPL(rio_request_dma);
@@ -1547,6 +1556,41 @@
EXPORT_SYMBOL_GPL(rio_release_dma);
/**
+ * rio_dma_prep_xfer - RapidIO specific wrapper
+ * for device_prep_slave_sg callback defined by DMAENGINE.
+ * @dchan: DMA channel to configure
+ * @destid: target RapidIO device destination ID
+ * @data: RIO specific data descriptor
+ * @direction: DMA data transfer direction (TO or FROM the device)
+ * @flags: dmaengine defined flags
+ *
+ * Initializes RapidIO capable DMA channel for the specified data transfer.
+ * Uses DMA channel private extension to pass information related to remote
+ * target RIO device.
+ * Returns pointer to DMA transaction descriptor or NULL if failed.
+ */
+struct dma_async_tx_descriptor *rio_dma_prep_xfer(struct dma_chan *dchan,
+ u16 destid, struct rio_dma_data *data,
+ enum dma_transfer_direction direction, unsigned long flags)
+{
+ struct rio_dma_ext rio_ext;
+
+ if (dchan->device->device_prep_slave_sg == NULL) {
+ pr_err("%s: prep_rio_sg == NULL\n", __func__);
+ return NULL;
+ }
+
+ rio_ext.destid = destid;
+ rio_ext.rio_addr_u = data->rio_addr_u;
+ rio_ext.rio_addr = data->rio_addr;
+ rio_ext.wr_type = data->wr_type;
+
+ return dmaengine_prep_rio_sg(dchan, data->sg, data->sg_len,
+ direction, flags, &rio_ext);
+}
+EXPORT_SYMBOL_GPL(rio_dma_prep_xfer);
+
+/**
* rio_dma_prep_slave_sg - RapidIO specific wrapper
* for device_prep_slave_sg callback defined by DMAENGINE.
* @rdev: RIO device control structure
@@ -1564,23 +1608,7 @@
struct dma_chan *dchan, struct rio_dma_data *data,
enum dma_transfer_direction direction, unsigned long flags)
{
- struct dma_async_tx_descriptor *txd = NULL;
- struct rio_dma_ext rio_ext;
-
- if (dchan->device->device_prep_slave_sg == NULL) {
- pr_err("%s: prep_rio_sg == NULL\n", __func__);
- return NULL;
- }
-
- rio_ext.destid = rdev->destid;
- rio_ext.rio_addr_u = data->rio_addr_u;
- rio_ext.rio_addr = data->rio_addr;
- rio_ext.wr_type = data->wr_type;
-
- txd = dmaengine_prep_rio_sg(dchan, data->sg, data->sg_len,
- direction, flags, &rio_ext);
-
- return txd;
+ return rio_dma_prep_xfer(dchan, rdev->destid, data, direction, flags);
}
EXPORT_SYMBOL_GPL(rio_dma_prep_slave_sg);
diff --git a/include/linux/rio_drv.h b/include/linux/rio_drv.h
index 5059994..9fc2f21 100644
--- a/include/linux/rio_drv.h
+++ b/include/linux/rio_drv.h
@@ -384,11 +384,16 @@
#ifdef CONFIG_RAPIDIO_DMA_ENGINE
extern struct dma_chan *rio_request_dma(struct rio_dev *rdev);
+extern struct dma_chan *rio_request_mport_dma(struct rio_mport *mport);
extern void rio_release_dma(struct dma_chan *dchan);
extern struct dma_async_tx_descriptor *rio_dma_prep_slave_sg(
struct rio_dev *rdev, struct dma_chan *dchan,
struct rio_dma_data *data,
enum dma_transfer_direction direction, unsigned long flags);
+extern struct dma_async_tx_descriptor *rio_dma_prep_xfer(
+ struct dma_chan *dchan, u16 destid,
+ struct rio_dma_data *data,
+ enum dma_transfer_direction direction, unsigned long flags);
#endif
/**