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-rw-r--r--drivers/dma/fsldma.c173
1 files changed, 129 insertions, 44 deletions
diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index 507b29716bbd..6a905929ef01 100644
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -967,6 +967,10 @@ static enum dma_status fsl_dma_is_complete(struct dma_chan *chan,
return dma_async_is_complete(cookie, last_complete, last_used);
}
+/*----------------------------------------------------------------------------*/
+/* Interrupt Handling */
+/*----------------------------------------------------------------------------*/
+
static irqreturn_t fsldma_chan_irq(int irq, void *data)
{
struct fsldma_chan *fsl_chan = data;
@@ -1048,24 +1052,116 @@ static irqreturn_t fsldma_chan_irq(int irq, void *data)
return IRQ_HANDLED;
}
-static irqreturn_t fsldma_irq(int irq, void *data)
+static void dma_do_tasklet(unsigned long data)
+{
+ struct fsldma_chan *fsl_chan = (struct fsldma_chan *)data;
+ fsl_chan_ld_cleanup(fsl_chan);
+}
+
+static irqreturn_t fsldma_ctrl_irq(int irq, void *data)
{
struct fsldma_device *fdev = data;
- int ch_nr;
- u32 gsr;
+ struct fsldma_chan *chan;
+ unsigned int handled = 0;
+ u32 gsr, mask;
+ int i;
gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->regs)
- : in_le32(fdev->regs);
- ch_nr = (32 - ffs(gsr)) / 8;
+ : in_le32(fdev->regs);
+ mask = 0xff000000;
+ dev_dbg(fdev->dev, "IRQ: gsr 0x%.8x\n", gsr);
- return fdev->chan[ch_nr] ? fsldma_chan_irq(irq,
- fdev->chan[ch_nr]) : IRQ_NONE;
+ for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
+ chan = fdev->chan[i];
+ if (!chan)
+ continue;
+
+ if (gsr & mask) {
+ dev_dbg(fdev->dev, "IRQ: chan %d\n", chan->id);
+ fsldma_chan_irq(irq, chan);
+ handled++;
+ }
+
+ gsr &= ~mask;
+ mask >>= 8;
+ }
+
+ return IRQ_RETVAL(handled);
}
-static void dma_do_tasklet(unsigned long data)
+static void fsldma_free_irqs(struct fsldma_device *fdev)
{
- struct fsldma_chan *fsl_chan = (struct fsldma_chan *)data;
- fsl_chan_ld_cleanup(fsl_chan);
+ struct fsldma_chan *chan;
+ int i;
+
+ if (fdev->irq != NO_IRQ) {
+ dev_dbg(fdev->dev, "free per-controller IRQ\n");
+ free_irq(fdev->irq, fdev);
+ return;
+ }
+
+ for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
+ chan = fdev->chan[i];
+ if (chan && chan->irq != NO_IRQ) {
+ dev_dbg(fdev->dev, "free channel %d IRQ\n", chan->id);
+ free_irq(chan->irq, chan);
+ }
+ }
+}
+
+static int fsldma_request_irqs(struct fsldma_device *fdev)
+{
+ struct fsldma_chan *chan;
+ int ret;
+ int i;
+
+ /* if we have a per-controller IRQ, use that */
+ if (fdev->irq != NO_IRQ) {
+ dev_dbg(fdev->dev, "request per-controller IRQ\n");
+ ret = request_irq(fdev->irq, fsldma_ctrl_irq, IRQF_SHARED,
+ "fsldma-controller", fdev);
+ return ret;
+ }
+
+ /* no per-controller IRQ, use the per-channel IRQs */
+ for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
+ chan = fdev->chan[i];
+ if (!chan)
+ continue;
+
+ if (chan->irq == NO_IRQ) {
+ dev_err(fdev->dev, "no interrupts property defined for "
+ "DMA channel %d. Please fix your "
+ "device tree\n", chan->id);
+ ret = -ENODEV;
+ goto out_unwind;
+ }
+
+ dev_dbg(fdev->dev, "request channel %d IRQ\n", chan->id);
+ ret = request_irq(chan->irq, fsldma_chan_irq, IRQF_SHARED,
+ "fsldma-chan", chan);
+ if (ret) {
+ dev_err(fdev->dev, "unable to request IRQ for DMA "
+ "channel %d\n", chan->id);
+ goto out_unwind;
+ }
+ }
+
+ return 0;
+
+out_unwind:
+ for (/* none */; i >= 0; i--) {
+ chan = fdev->chan[i];
+ if (!chan)
+ continue;
+
+ if (chan->irq == NO_IRQ)
+ continue;
+
+ free_irq(chan->irq, chan);
+ }
+
+ return ret;
}
/*----------------------------------------------------------------------------*/
@@ -1143,29 +1239,18 @@ static int __devinit fsl_dma_chan_probe(struct fsldma_device *fdev,
fchan->common.device = &fdev->common;
+ /* find the IRQ line, if it exists in the device tree */
+ fchan->irq = irq_of_parse_and_map(node, 0);
+
/* Add the channel to DMA device channel list */
list_add_tail(&fchan->common.device_node, &fdev->common.channels);
fdev->common.chancnt++;
- fchan->irq = irq_of_parse_and_map(node, 0);
- if (fchan->irq != NO_IRQ) {
- err = request_irq(fchan->irq, &fsldma_chan_irq,
- IRQF_SHARED, "fsldma-channel", fchan);
- if (err) {
- dev_err(fdev->dev, "unable to request IRQ "
- "for channel %d\n", fchan->id);
- goto out_list_del;
- }
- }
-
dev_info(fdev->dev, "#%d (%s), irq %d\n", fchan->id, compatible,
fchan->irq != NO_IRQ ? fchan->irq : fdev->irq);
return 0;
-out_list_del:
- irq_dispose_mapping(fchan->irq);
- list_del_init(&fchan->common.device_node);
out_iounmap_regs:
iounmap(fchan->regs);
out_free_fchan:
@@ -1176,11 +1261,7 @@ out_return:
static void fsl_dma_chan_remove(struct fsldma_chan *fchan)
{
- if (fchan->irq != NO_IRQ) {
- free_irq(fchan->irq, fchan);
- irq_dispose_mapping(fchan->irq);
- }
-
+ irq_dispose_mapping(fchan->irq);
list_del(&fchan->common.device_node);
iounmap(fchan->regs);
kfree(fchan);
@@ -1211,6 +1292,9 @@ static int __devinit fsldma_of_probe(struct of_device *op,
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->node, 0);
+
dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask);
dma_cap_set(DMA_INTERRUPT, fdev->common.cap_mask);
dma_cap_set(DMA_SLAVE, fdev->common.cap_mask);
@@ -1224,16 +1308,6 @@ static int __devinit fsldma_of_probe(struct of_device *op,
fdev->common.device_terminate_all = fsl_dma_device_terminate_all;
fdev->common.dev = &op->dev;
- fdev->irq = irq_of_parse_and_map(op->node, 0);
- if (fdev->irq != NO_IRQ) {
- err = request_irq(fdev->irq, &fsldma_irq, IRQF_SHARED,
- "fsldma-device", fdev);
- if (err) {
- dev_err(&op->dev, "unable to request IRQ\n");
- goto out_iounmap_regs;
- }
- }
-
dev_set_drvdata(&op->dev, fdev);
/*
@@ -1255,12 +1329,24 @@ static int __devinit fsldma_of_probe(struct of_device *op,
}
}
+ /*
+ * Hookup the IRQ handler(s)
+ *
+ * If we have a per-controller interrupt, we prefer that to the
+ * per-channel interrupts to reduce the number of shared interrupt
+ * handlers on the same IRQ line
+ */
+ err = fsldma_request_irqs(fdev);
+ if (err) {
+ dev_err(fdev->dev, "unable to request IRQs\n");
+ goto out_free_fdev;
+ }
+
dma_async_device_register(&fdev->common);
return 0;
-out_iounmap_regs:
- iounmap(fdev->regs);
out_free_fdev:
+ irq_dispose_mapping(fdev->irq);
kfree(fdev);
out_return:
return err;
@@ -1274,14 +1360,13 @@ static int fsldma_of_remove(struct of_device *op)
fdev = dev_get_drvdata(&op->dev);
dma_async_device_unregister(&fdev->common);
+ fsldma_free_irqs(fdev);
+
for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
if (fdev->chan[i])
fsl_dma_chan_remove(fdev->chan[i]);
}
- if (fdev->irq != NO_IRQ)
- free_irq(fdev->irq, fdev);
-
iounmap(fdev->regs);
dev_set_drvdata(&op->dev, NULL);
kfree(fdev);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.