[PATCH 2/2] DMA: Freescale: update driver to support 8-channel DMA engine

From: hongbo.zhang
Date: Sun Jun 30 2013 - 23:21:09 EST


From: Hongbo Zhang <hongbo.zhang@xxxxxxxxxxxxx>

This patch adds support to 8-channel DMA engine, thus the driver works for both
the new 8-channel and the legacy 4-channel DMA engines.

Signed-off-by: Hongbo Zhang <hongbo.zhang@xxxxxxxxxxxxx>
---
drivers/dma/fsldma.c | 48 ++++++++++++++++++++++++++++++++++--------------
drivers/dma/fsldma.h | 4 ++--
2 files changed, 36 insertions(+), 16 deletions(-)

diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index 4fc2980..0f453ea 100644
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -1119,27 +1119,33 @@ static irqreturn_t fsldma_ctrl_irq(int irq, void *data)
struct fsldma_device *fdev = data;
struct fsldma_chan *chan;
unsigned int handled = 0;
- u32 gsr, mask;
+ u8 chan_sr[round_up(FSL_DMA_MAX_CHANS_PER_DEVICE, 4)];
+ u32 gsr;
int i;

- gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->regs)
- : in_le32(fdev->regs);
- mask = 0xff000000;
- dev_dbg(fdev->dev, "IRQ: gsr 0x%.8x\n", gsr);
+ memset(&chan_sr, 0, sizeof(chan_sr));
+ gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->regs0)
+ : in_le32(fdev->regs0);
+ memcpy(&chan_sr[0], &gsr, 4);
+ dev_dbg(fdev->dev, "IRQ: gsr0 0x%.8x\n", gsr);
+
+ if (of_device_is_compatible(fdev->dev->of_node, "fsl,eloplus-dma2")) {
+ gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ?
+ in_be32(fdev->regs1) : in_le32(fdev->regs1);
+ memcpy(&chan_sr[4], &gsr, 4);
+ dev_dbg(fdev->dev, "IRQ: gsr1 0x%.8x\n", gsr);
+ }

for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
chan = fdev->chan[i];
if (!chan)
continue;

- if (gsr & mask) {
+ if (chan_sr[i]) {
dev_dbg(fdev->dev, "IRQ: chan %d\n", chan->id);
fsldma_chan_irq(irq, chan);
handled++;
}
-
- gsr &= ~mask;
- mask >>= 8;
}

return IRQ_RETVAL(handled);
@@ -1261,7 +1267,9 @@ static int fsl_dma_chan_probe(struct fsldma_device *fdev,
WARN_ON(fdev->feature != chan->feature);

chan->dev = fdev->dev;
- chan->id = ((res.start - 0x100) & 0xfff) >> 7;
+ chan->id = (res.start & 0xfff) < 0x300 ?
+ ((res.start - 0x100) & 0xfff) >> 7 :
+ ((res.start - 0x200) & 0xfff) >> 7;
if (chan->id >= FSL_DMA_MAX_CHANS_PER_DEVICE) {
dev_err(fdev->dev, "too many channels for device\n");
err = -EINVAL;
@@ -1341,13 +1349,22 @@ static int fsldma_of_probe(struct platform_device *op)
INIT_LIST_HEAD(&fdev->common.channels);

/* ioremap the registers for use */
- fdev->regs = of_iomap(op->dev.of_node, 0);
- if (!fdev->regs) {
- dev_err(&op->dev, "unable to ioremap registers\n");
+ fdev->regs0 = of_iomap(op->dev.of_node, 0);
+ if (!fdev->regs0) {
+ dev_err(&op->dev, "unable to ioremap register0\n");
err = -ENOMEM;
goto out_free_fdev;
}

+ if (of_device_is_compatible(op->dev.of_node, "fsl,eloplus-dma2")) {
+ fdev->regs1 = of_iomap(op->dev.of_node, 1);
+ if (!fdev->regs1) {
+ dev_err(&op->dev, "unable to ioremap register1\n");
+ err = -ENOMEM;
+ goto out_free_fdev;
+ }
+ }
+
/* map the channel IRQ if it exists, but don't hookup the handler yet */
fdev->irq = irq_of_parse_and_map(op->dev.of_node, 0);

@@ -1427,7 +1444,9 @@ static int fsldma_of_remove(struct platform_device *op)
fsl_dma_chan_remove(fdev->chan[i]);
}

- iounmap(fdev->regs);
+ iounmap(fdev->regs0);
+ if (of_device_is_compatible(op->dev.of_node, "fsl,eloplus-dma2"))
+ iounmap(fdev->regs1);
dev_set_drvdata(&op->dev, NULL);
kfree(fdev);

@@ -1436,6 +1455,7 @@ static int fsldma_of_remove(struct platform_device *op)

static const struct of_device_id fsldma_of_ids[] = {
{ .compatible = "fsl,eloplus-dma", },
+ { .compatible = "fsl,eloplus-dma2", },
{ .compatible = "fsl,elo-dma", },
{}
};
diff --git a/drivers/dma/fsldma.h b/drivers/dma/fsldma.h
index f5c3879..880664d 100644
--- a/drivers/dma/fsldma.h
+++ b/drivers/dma/fsldma.h
@@ -112,10 +112,10 @@ struct fsldma_chan_regs {
};

struct fsldma_chan;
-#define FSL_DMA_MAX_CHANS_PER_DEVICE 4
+#define FSL_DMA_MAX_CHANS_PER_DEVICE 8

struct fsldma_device {
- void __iomem *regs; /* DGSR register base */
+ void __iomem *regs0, *regs1; /* DGSR registers */
struct device *dev;
struct dma_device common;
struct fsldma_chan *chan[FSL_DMA_MAX_CHANS_PER_DEVICE];
--
1.7.9.5



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