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authorLinus Torvalds <torvalds@linux-foundation.org>2012-03-31 02:31:56 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-31 02:31:56 +0200
commit623ff7739e7c00fa3d55dbfd42a492a68298fd7a (patch)
tree0b7461753a1b13b27ea2958a7d48c6efb47bba54 /drivers/dma/mxs-dma.c
parentMerge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/... (diff)
parentmtd: docg3 add protection against concurrency (diff)
downloadlinux-623ff7739e7c00fa3d55dbfd42a492a68298fd7a.tar.xz
linux-623ff7739e7c00fa3d55dbfd42a492a68298fd7a.zip
Merge tag 'for-linus-3.4' of git://git.infradead.org/mtd-2.6
Pull MTD changes from David Woodhouse: - Artem's cleanup of the MTD API continues apace. - Fixes and improvements for ST FSMC and SuperH FLCTL NAND, amongst others. - More work on DiskOnChip G3, new driver for DiskOnChip G4. - Clean up debug/warning printks in JFFS2 to use pr_<level>. Fix up various trivial conflicts, largely due to changes in calling conventions for things like dmaengine_prep_slave_sg() (new inline wrapper to hide new parameter, clashing with rewrite of previously last parameter that used to be an 'append' flag, and is now a bitmap of 'unsigned long flags'). (Also some header file fallout - like so many merges this merge window - and silly conflicts with sparse fixes) * tag 'for-linus-3.4' of git://git.infradead.org/mtd-2.6: (120 commits) mtd: docg3 add protection against concurrency mtd: docg3 refactor cascade floors structure mtd: docg3 increase write/erase timeout mtd: docg3 fix inbound calculations mtd: nand: gpmi: fix function annotations mtd: phram: fix section mismatch for phram_setup mtd: unify initialization of erase_info->fail_addr mtd: support ONFI multi lun NAND mtd: sm_ftl: fix typo in major number. mtd: add device-tree support to spear_smi mtd: spear_smi: Remove default partition information from driver mtd: Add device-tree support to fsmc_nand mtd: fix section mismatch for doc_probe_device mtd: nand/fsmc: Remove sparse warnings and errors mtd: nand/fsmc: Add DMA support mtd: nand/fsmc: Access the NAND device word by word whenever possible mtd: nand/fsmc: Use dev_err to report error scenario mtd: nand/fsmc: Use devm routines mtd: nand/fsmc: Modify fsmc driver to accept nand timing parameters via platform mtd: fsmc_nand: add pm callbacks to support hibernation ...
Diffstat (limited to 'drivers/dma/mxs-dma.c')
-rw-r--r--drivers/dma/mxs-dma.c34
1 files changed, 29 insertions, 5 deletions
diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
index 65334c49b71e..c81ef7e10e08 100644
--- a/drivers/dma/mxs-dma.c
+++ b/drivers/dma/mxs-dma.c
@@ -22,10 +22,10 @@
#include <linux/platform_device.h>
#include <linux/dmaengine.h>
#include <linux/delay.h>
+#include <linux/fsl/mxs-dma.h>
#include <asm/irq.h>
#include <mach/mxs.h>
-#include <mach/dma.h>
#include <mach/common.h>
#include "dmaengine.h"
@@ -337,10 +337,32 @@ static void mxs_dma_free_chan_resources(struct dma_chan *chan)
clk_disable_unprepare(mxs_dma->clk);
}
+/*
+ * How to use the flags for ->device_prep_slave_sg() :
+ * [1] If there is only one DMA command in the DMA chain, the code should be:
+ * ......
+ * ->device_prep_slave_sg(DMA_CTRL_ACK);
+ * ......
+ * [2] If there are two DMA commands in the DMA chain, the code should be
+ * ......
+ * ->device_prep_slave_sg(0);
+ * ......
+ * ->device_prep_slave_sg(DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ * ......
+ * [3] If there are more than two DMA commands in the DMA chain, the code
+ * should be:
+ * ......
+ * ->device_prep_slave_sg(0); // First
+ * ......
+ * ->device_prep_slave_sg(DMA_PREP_INTERRUPT [| DMA_CTRL_ACK]);
+ * ......
+ * ->device_prep_slave_sg(DMA_PREP_INTERRUPT | DMA_CTRL_ACK); // Last
+ * ......
+ */
static struct dma_async_tx_descriptor *mxs_dma_prep_slave_sg(
struct dma_chan *chan, struct scatterlist *sgl,
unsigned int sg_len, enum dma_transfer_direction direction,
- unsigned long append, void *context)
+ unsigned long flags, void *context)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
@@ -348,6 +370,7 @@ static struct dma_async_tx_descriptor *mxs_dma_prep_slave_sg(
struct scatterlist *sg;
int i, j;
u32 *pio;
+ bool append = flags & DMA_PREP_INTERRUPT;
int idx = append ? mxs_chan->desc_count : 0;
if (mxs_chan->status == DMA_IN_PROGRESS && !append)
@@ -374,7 +397,6 @@ static struct dma_async_tx_descriptor *mxs_dma_prep_slave_sg(
ccw->bits |= CCW_CHAIN;
ccw->bits &= ~CCW_IRQ;
ccw->bits &= ~CCW_DEC_SEM;
- ccw->bits &= ~CCW_WAIT4END;
} else {
idx = 0;
}
@@ -389,7 +411,8 @@ static struct dma_async_tx_descriptor *mxs_dma_prep_slave_sg(
ccw->bits = 0;
ccw->bits |= CCW_IRQ;
ccw->bits |= CCW_DEC_SEM;
- ccw->bits |= CCW_WAIT4END;
+ if (flags & DMA_CTRL_ACK)
+ ccw->bits |= CCW_WAIT4END;
ccw->bits |= CCW_HALT_ON_TERM;
ccw->bits |= CCW_TERM_FLUSH;
ccw->bits |= BF_CCW(sg_len, PIO_NUM);
@@ -420,7 +443,8 @@ static struct dma_async_tx_descriptor *mxs_dma_prep_slave_sg(
ccw->bits &= ~CCW_CHAIN;
ccw->bits |= CCW_IRQ;
ccw->bits |= CCW_DEC_SEM;
- ccw->bits |= CCW_WAIT4END;
+ if (flags & DMA_CTRL_ACK)
+ ccw->bits |= CCW_WAIT4END;
}
}
}