fsldma: clean up the OF subsystem routines

This fixes some errors in the cleanup paths of the OF subsystem, including
missing checks for ioremap failing. Also, some variables were renamed for
brevity.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index c2db754..507b297 100644
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -40,7 +40,7 @@
 static void dma_init(struct fsldma_chan *fsl_chan)
 {
 	/* Reset the channel */
-	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, 0, 32);
+	DMA_OUT(fsl_chan, &fsl_chan->regs->mr, 0, 32);
 
 	switch (fsl_chan->feature & FSL_DMA_IP_MASK) {
 	case FSL_DMA_IP_85XX:
@@ -49,7 +49,7 @@
 		 * EOSIE - End of segments interrupt enable (basic mode)
 		 * EOLNIE - End of links interrupt enable
 		 */
-		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EIE
+		DMA_OUT(fsl_chan, &fsl_chan->regs->mr, FSL_DMA_MR_EIE
 				| FSL_DMA_MR_EOLNIE | FSL_DMA_MR_EOSIE, 32);
 		break;
 	case FSL_DMA_IP_83XX:
@@ -57,7 +57,7 @@
 		 * EOTIE - End-of-transfer interrupt enable
 		 * PRC_RM - PCI read multiple
 		 */
-		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EOTIE
+		DMA_OUT(fsl_chan, &fsl_chan->regs->mr, FSL_DMA_MR_EOTIE
 				| FSL_DMA_MR_PRC_RM, 32);
 		break;
 	}
@@ -66,12 +66,12 @@
 
 static void set_sr(struct fsldma_chan *fsl_chan, u32 val)
 {
-	DMA_OUT(fsl_chan, &fsl_chan->reg_base->sr, val, 32);
+	DMA_OUT(fsl_chan, &fsl_chan->regs->sr, val, 32);
 }
 
 static u32 get_sr(struct fsldma_chan *fsl_chan)
 {
-	return DMA_IN(fsl_chan, &fsl_chan->reg_base->sr, 32);
+	return DMA_IN(fsl_chan, &fsl_chan->regs->sr, 32);
 }
 
 static void set_desc_cnt(struct fsldma_chan *fsl_chan,
@@ -112,27 +112,27 @@
 
 static void set_cdar(struct fsldma_chan *fsl_chan, dma_addr_t addr)
 {
-	DMA_OUT(fsl_chan, &fsl_chan->reg_base->cdar, addr | FSL_DMA_SNEN, 64);
+	DMA_OUT(fsl_chan, &fsl_chan->regs->cdar, addr | FSL_DMA_SNEN, 64);
 }
 
 static dma_addr_t get_cdar(struct fsldma_chan *fsl_chan)
 {
-	return DMA_IN(fsl_chan, &fsl_chan->reg_base->cdar, 64) & ~FSL_DMA_SNEN;
+	return DMA_IN(fsl_chan, &fsl_chan->regs->cdar, 64) & ~FSL_DMA_SNEN;
 }
 
 static void set_ndar(struct fsldma_chan *fsl_chan, dma_addr_t addr)
 {
-	DMA_OUT(fsl_chan, &fsl_chan->reg_base->ndar, addr, 64);
+	DMA_OUT(fsl_chan, &fsl_chan->regs->ndar, addr, 64);
 }
 
 static dma_addr_t get_ndar(struct fsldma_chan *fsl_chan)
 {
-	return DMA_IN(fsl_chan, &fsl_chan->reg_base->ndar, 64);
+	return DMA_IN(fsl_chan, &fsl_chan->regs->ndar, 64);
 }
 
 static u32 get_bcr(struct fsldma_chan *fsl_chan)
 {
-	return DMA_IN(fsl_chan, &fsl_chan->reg_base->bcr, 32);
+	return DMA_IN(fsl_chan, &fsl_chan->regs->bcr, 32);
 }
 
 static int dma_is_idle(struct fsldma_chan *fsl_chan)
@@ -145,11 +145,11 @@
 {
 	u32 mode;
 
-	mode = DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32);
+	mode = DMA_IN(fsl_chan, &fsl_chan->regs->mr, 32);
 
 	if ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) {
 		if (fsl_chan->feature & FSL_DMA_CHAN_PAUSE_EXT) {
-			DMA_OUT(fsl_chan, &fsl_chan->reg_base->bcr, 0, 32);
+			DMA_OUT(fsl_chan, &fsl_chan->regs->bcr, 0, 32);
 			mode |= FSL_DMA_MR_EMP_EN;
 		} else {
 			mode &= ~FSL_DMA_MR_EMP_EN;
@@ -161,7 +161,7 @@
 	else
 		mode |= FSL_DMA_MR_CS;
 
-	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);
+	DMA_OUT(fsl_chan, &fsl_chan->regs->mr, mode, 32);
 }
 
 static void dma_halt(struct fsldma_chan *fsl_chan)
@@ -169,12 +169,12 @@
 	u32 mode;
 	int i;
 
-	mode = DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32);
+	mode = DMA_IN(fsl_chan, &fsl_chan->regs->mr, 32);
 	mode |= FSL_DMA_MR_CA;
-	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);
+	DMA_OUT(fsl_chan, &fsl_chan->regs->mr, mode, 32);
 
 	mode &= ~(FSL_DMA_MR_CS | FSL_DMA_MR_EMS_EN | FSL_DMA_MR_CA);
-	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);
+	DMA_OUT(fsl_chan, &fsl_chan->regs->mr, mode, 32);
 
 	for (i = 0; i < 100; i++) {
 		if (dma_is_idle(fsl_chan))
@@ -235,7 +235,7 @@
 {
 	u32 mode;
 
-	mode = DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32);
+	mode = DMA_IN(fsl_chan, &fsl_chan->regs->mr, 32);
 
 	switch (size) {
 	case 0:
@@ -249,7 +249,7 @@
 		break;
 	}
 
-	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);
+	DMA_OUT(fsl_chan, &fsl_chan->regs->mr, mode, 32);
 }
 
 /**
@@ -267,7 +267,7 @@
 {
 	u32 mode;
 
-	mode = DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32);
+	mode = DMA_IN(fsl_chan, &fsl_chan->regs->mr, 32);
 
 	switch (size) {
 	case 0:
@@ -281,7 +281,7 @@
 		break;
 	}
 
-	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);
+	DMA_OUT(fsl_chan, &fsl_chan->regs->mr, mode, 32);
 }
 
 /**
@@ -302,10 +302,10 @@
 
 	BUG_ON(size > 1024);
 
-	mode = DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32);
+	mode = DMA_IN(fsl_chan, &fsl_chan->regs->mr, 32);
 	mode |= (__ilog2(size) << 24) & 0x0f000000;
 
-	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, mode, 32);
+	DMA_OUT(fsl_chan, &fsl_chan->regs->mr, mode, 32);
 }
 
 /**
@@ -967,7 +967,7 @@
 	return dma_async_is_complete(cookie, last_complete, last_used);
 }
 
-static irqreturn_t fsl_dma_chan_do_interrupt(int irq, void *data)
+static irqreturn_t fsldma_chan_irq(int irq, void *data)
 {
 	struct fsldma_chan *fsl_chan = data;
 	u32 stat;
@@ -1048,17 +1048,17 @@
 	return IRQ_HANDLED;
 }
 
-static irqreturn_t fsl_dma_do_interrupt(int irq, void *data)
+static irqreturn_t fsldma_irq(int irq, void *data)
 {
 	struct fsldma_device *fdev = data;
 	int ch_nr;
 	u32 gsr;
 
-	gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->reg_base)
-			: in_le32(fdev->reg_base);
+	gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->regs)
+			: in_le32(fdev->regs);
 	ch_nr = (32 - ffs(gsr)) / 8;
 
-	return fdev->chan[ch_nr] ? fsl_dma_chan_do_interrupt(irq,
+	return fdev->chan[ch_nr] ? fsldma_chan_irq(irq,
 			fdev->chan[ch_nr]) : IRQ_NONE;
 }
 
@@ -1075,140 +1075,142 @@
 static int __devinit fsl_dma_chan_probe(struct fsldma_device *fdev,
 	struct device_node *node, u32 feature, const char *compatible)
 {
-	struct fsldma_chan *new_fsl_chan;
+	struct fsldma_chan *fchan;
 	struct resource res;
 	int err;
 
 	/* alloc channel */
-	new_fsl_chan = kzalloc(sizeof(*new_fsl_chan), GFP_KERNEL);
-	if (!new_fsl_chan) {
-		dev_err(fdev->dev, "No free memory for allocating "
-				"dma channels!\n");
-		return -ENOMEM;
+	fchan = kzalloc(sizeof(*fchan), GFP_KERNEL);
+	if (!fchan) {
+		dev_err(fdev->dev, "no free memory for DMA channels!\n");
+		err = -ENOMEM;
+		goto out_return;
 	}
 
-	/* get dma channel register base */
+	/* ioremap registers for use */
+	fchan->regs = of_iomap(node, 0);
+	if (!fchan->regs) {
+		dev_err(fdev->dev, "unable to ioremap registers\n");
+		err = -ENOMEM;
+		goto out_free_fchan;
+	}
+
 	err = of_address_to_resource(node, 0, &res);
 	if (err) {
-		dev_err(fdev->dev, "Can't get %s property 'reg'\n",
-				node->full_name);
-		goto err_no_reg;
+		dev_err(fdev->dev, "unable to find 'reg' property\n");
+		goto out_iounmap_regs;
 	}
 
-	new_fsl_chan->feature = feature;
-
+	fchan->feature = feature;
 	if (!fdev->feature)
-		fdev->feature = new_fsl_chan->feature;
+		fdev->feature = fchan->feature;
 
-	/* If the DMA device's feature is different than its channels',
-	 * report the bug.
+	/*
+	 * If the DMA device's feature is different than the feature
+	 * of its channels, report the bug
 	 */
-	WARN_ON(fdev->feature != new_fsl_chan->feature);
+	WARN_ON(fdev->feature != fchan->feature);
 
-	new_fsl_chan->dev = fdev->dev;
-	new_fsl_chan->reg_base = ioremap(res.start, resource_size(&res));
-	new_fsl_chan->id = ((res.start - 0x100) & 0xfff) >> 7;
-	if (new_fsl_chan->id >= FSL_DMA_MAX_CHANS_PER_DEVICE) {
-		dev_err(fdev->dev, "There is no %d channel!\n",
-				new_fsl_chan->id);
+	fchan->dev = fdev->dev;
+	fchan->id = ((res.start - 0x100) & 0xfff) >> 7;
+	if (fchan->id >= FSL_DMA_MAX_CHANS_PER_DEVICE) {
+		dev_err(fdev->dev, "too many channels for device\n");
 		err = -EINVAL;
-		goto err_no_chan;
+		goto out_iounmap_regs;
 	}
-	fdev->chan[new_fsl_chan->id] = new_fsl_chan;
-	tasklet_init(&new_fsl_chan->tasklet, dma_do_tasklet,
-			(unsigned long)new_fsl_chan);
 
-	/* Init the channel */
-	dma_init(new_fsl_chan);
+	fdev->chan[fchan->id] = fchan;
+	tasklet_init(&fchan->tasklet, dma_do_tasklet, (unsigned long)fchan);
+
+	/* Initialize the channel */
+	dma_init(fchan);
 
 	/* Clear cdar registers */
-	set_cdar(new_fsl_chan, 0);
+	set_cdar(fchan, 0);
 
-	switch (new_fsl_chan->feature & FSL_DMA_IP_MASK) {
+	switch (fchan->feature & FSL_DMA_IP_MASK) {
 	case FSL_DMA_IP_85XX:
-		new_fsl_chan->toggle_ext_pause = fsl_chan_toggle_ext_pause;
+		fchan->toggle_ext_pause = fsl_chan_toggle_ext_pause;
 	case FSL_DMA_IP_83XX:
-		new_fsl_chan->toggle_ext_start = fsl_chan_toggle_ext_start;
-		new_fsl_chan->set_src_loop_size = fsl_chan_set_src_loop_size;
-		new_fsl_chan->set_dst_loop_size = fsl_chan_set_dst_loop_size;
-		new_fsl_chan->set_request_count = fsl_chan_set_request_count;
+		fchan->toggle_ext_start = fsl_chan_toggle_ext_start;
+		fchan->set_src_loop_size = fsl_chan_set_src_loop_size;
+		fchan->set_dst_loop_size = fsl_chan_set_dst_loop_size;
+		fchan->set_request_count = fsl_chan_set_request_count;
 	}
 
-	spin_lock_init(&new_fsl_chan->desc_lock);
-	INIT_LIST_HEAD(&new_fsl_chan->ld_queue);
+	spin_lock_init(&fchan->desc_lock);
+	INIT_LIST_HEAD(&fchan->ld_queue);
 
-	new_fsl_chan->common.device = &fdev->common;
+	fchan->common.device = &fdev->common;
 
 	/* Add the channel to DMA device channel list */
-	list_add_tail(&new_fsl_chan->common.device_node,
-			&fdev->common.channels);
+	list_add_tail(&fchan->common.device_node, &fdev->common.channels);
 	fdev->common.chancnt++;
 
-	new_fsl_chan->irq = irq_of_parse_and_map(node, 0);
-	if (new_fsl_chan->irq != NO_IRQ) {
-		err = request_irq(new_fsl_chan->irq,
-					&fsl_dma_chan_do_interrupt, IRQF_SHARED,
-					"fsldma-channel", new_fsl_chan);
+	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, "DMA channel %s request_irq error "
-				"with return %d\n", node->full_name, err);
-			goto err_no_irq;
+			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", new_fsl_chan->id,
-		 compatible,
-		 new_fsl_chan->irq != NO_IRQ ? new_fsl_chan->irq : fdev->irq);
+	dev_info(fdev->dev, "#%d (%s), irq %d\n", fchan->id, compatible,
+		 fchan->irq != NO_IRQ ? fchan->irq : fdev->irq);
 
 	return 0;
 
-err_no_irq:
-	list_del(&new_fsl_chan->common.device_node);
-err_no_chan:
-	iounmap(new_fsl_chan->reg_base);
-err_no_reg:
-	kfree(new_fsl_chan);
+out_list_del:
+	irq_dispose_mapping(fchan->irq);
+	list_del_init(&fchan->common.device_node);
+out_iounmap_regs:
+	iounmap(fchan->regs);
+out_free_fchan:
+	kfree(fchan);
+out_return:
 	return err;
 }
 
 static void fsl_dma_chan_remove(struct fsldma_chan *fchan)
 {
-	if (fchan->irq != NO_IRQ)
+	if (fchan->irq != NO_IRQ) {
 		free_irq(fchan->irq, fchan);
+		irq_dispose_mapping(fchan->irq);
+	}
+
 	list_del(&fchan->common.device_node);
-	iounmap(fchan->reg_base);
+	iounmap(fchan->regs);
 	kfree(fchan);
 }
 
-static int __devinit fsldma_of_probe(struct of_device *dev,
+static int __devinit fsldma_of_probe(struct of_device *op,
 			const struct of_device_id *match)
 {
-	int err;
 	struct fsldma_device *fdev;
 	struct device_node *child;
-	struct resource res;
+	int err;
 
 	fdev = kzalloc(sizeof(*fdev), GFP_KERNEL);
 	if (!fdev) {
-		dev_err(&dev->dev, "No enough memory for 'priv'\n");
-		return -ENOMEM;
+		dev_err(&op->dev, "No enough memory for 'priv'\n");
+		err = -ENOMEM;
+		goto out_return;
 	}
-	fdev->dev = &dev->dev;
+
+	fdev->dev = &op->dev;
 	INIT_LIST_HEAD(&fdev->common.channels);
 
-	/* get DMA controller register base */
-	err = of_address_to_resource(dev->node, 0, &res);
-	if (err) {
-		dev_err(&dev->dev, "Can't get %s property 'reg'\n",
-				dev->node->full_name);
-		goto err_no_reg;
+	/* ioremap the registers for use */
+	fdev->regs = of_iomap(op->node, 0);
+	if (!fdev->regs) {
+		dev_err(&op->dev, "unable to ioremap registers\n");
+		err = -ENOMEM;
+		goto out_free_fdev;
 	}
 
-	dev_info(&dev->dev, "Probe the Freescale DMA driver for %s "
-			"controller at 0x%llx...\n",
-			match->compatible, (unsigned long long)res.start);
-	fdev->reg_base = ioremap(res.start, resource_size(&res));
-
 	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);
@@ -1220,66 +1222,69 @@
 	fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
 	fdev->common.device_prep_slave_sg = fsl_dma_prep_slave_sg;
 	fdev->common.device_terminate_all = fsl_dma_device_terminate_all;
-	fdev->common.dev = &dev->dev;
+	fdev->common.dev = &op->dev;
 
-	fdev->irq = irq_of_parse_and_map(dev->node, 0);
+	fdev->irq = irq_of_parse_and_map(op->node, 0);
 	if (fdev->irq != NO_IRQ) {
-		err = request_irq(fdev->irq, &fsl_dma_do_interrupt, IRQF_SHARED,
-					"fsldma-device", fdev);
+		err = request_irq(fdev->irq, &fsldma_irq, IRQF_SHARED,
+				  "fsldma-device", fdev);
 		if (err) {
-			dev_err(&dev->dev, "DMA device request_irq error "
-				"with return %d\n", err);
-			goto err;
+			dev_err(&op->dev, "unable to request IRQ\n");
+			goto out_iounmap_regs;
 		}
 	}
 
-	dev_set_drvdata(&(dev->dev), fdev);
+	dev_set_drvdata(&op->dev, fdev);
 
-	/* We cannot use of_platform_bus_probe() because there is no
-	 * of_platform_bus_remove.  Instead, we manually instantiate every DMA
+	/*
+	 * We cannot use of_platform_bus_probe() because there is no
+	 * of_platform_bus_remove(). Instead, we manually instantiate every DMA
 	 * channel object.
 	 */
-	for_each_child_of_node(dev->node, child) {
-		if (of_device_is_compatible(child, "fsl,eloplus-dma-channel"))
+	for_each_child_of_node(op->node, child) {
+		if (of_device_is_compatible(child, "fsl,eloplus-dma-channel")) {
 			fsl_dma_chan_probe(fdev, child,
 				FSL_DMA_IP_85XX | FSL_DMA_BIG_ENDIAN,
 				"fsl,eloplus-dma-channel");
-		if (of_device_is_compatible(child, "fsl,elo-dma-channel"))
+		}
+
+		if (of_device_is_compatible(child, "fsl,elo-dma-channel")) {
 			fsl_dma_chan_probe(fdev, child,
 				FSL_DMA_IP_83XX | FSL_DMA_LITTLE_ENDIAN,
 				"fsl,elo-dma-channel");
+		}
 	}
 
 	dma_async_device_register(&fdev->common);
 	return 0;
 
-err:
-	iounmap(fdev->reg_base);
-err_no_reg:
+out_iounmap_regs:
+	iounmap(fdev->regs);
+out_free_fdev:
 	kfree(fdev);
+out_return:
 	return err;
 }
 
-static int fsldma_of_remove(struct of_device *of_dev)
+static int fsldma_of_remove(struct of_device *op)
 {
 	struct fsldma_device *fdev;
 	unsigned int i;
 
-	fdev = dev_get_drvdata(&of_dev->dev);
-
+	fdev = dev_get_drvdata(&op->dev);
 	dma_async_device_unregister(&fdev->common);
 
-	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++)
+	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->reg_base);
-
+	iounmap(fdev->regs);
+	dev_set_drvdata(&op->dev, NULL);
 	kfree(fdev);
-	dev_set_drvdata(&of_dev->dev, NULL);
 
 	return 0;
 }