2 files changed, 137 insertions, 44 deletions

diff --git a/Documentation/powerpc/dts-bindings/fsl/dma.txt b/Documentation/powerpc/dts-bindings/fsl/dma.txt
index 0732cdd05ba1..2a4b4bce6110 100644
--- a/Documentation/powerpc/dts-bindings/fsl/dma.txt
+++ b/Documentation/powerpc/dts-bindings/fsl/dma.txt
@@ -44,21 +44,29 @@ Example:
                         compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
                         cell-index = <0>;
                         reg = <0 0x80>;
+                        interrupt-parent = <&ipic>;
+                        interrupts = <71 8>;
                 };
                 dma-channel@80 {
                         compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
                         cell-index = <1>;
                         reg = <0x80 0x80>;
+                        interrupt-parent = <&ipic>;
+                        interrupts = <71 8>;
                 };
                 dma-channel@100 {
                         compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
                         cell-index = <2>;
                         reg = <0x100 0x80>;
+                        interrupt-parent = <&ipic>;
+                        interrupts = <71 8>;
                 };
                 dma-channel@180 {
                         compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
                         cell-index = <3>;
                         reg = <0x180 0x80>;
+                        interrupt-parent = <&ipic>;
+                        interrupts = <71 8>;
                 };
         };
 
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);