[PATCH] dmaengine: bestcomm: ioremap and get irq early

[Rosen Penev <rosenp@gmail.com>]

Doing so allows handling potential -EPROBE_DEFER before any work gets
done.

Replace the open-coded resource lookup, request_mem_region, ioremap and
the manual iounmap/release_mem_region cleanup in probe/remove with the
managed devm_platform_get_and_ioremap_resource() helper. This removes the
now-unused error-unmap/release paths and simplifies the driver.

Assisted-by: opencode:hy3-free
Signed-off-by: Rosen Penev <rosenp@gmail.com>

dmaengine: bestcomm: get irq early

platform_get_irq can return -EPROBE_DEFER, which is useful to avoid
doing extra work in such a case

Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/dma/bestcomm/bestcomm.c            | 70 ++++++----------------
 include/linux/fsl/bestcomm/bestcomm_priv.h |  2 +-
 2 files changed, 18 insertions(+), 54 deletions(-)

diff --git a/drivers/dma/bestcomm/bestcomm.c b/drivers/dma/bestcomm/bestcomm.c
index 432b43520ddc..55ad7bc34df7 100644
--- a/drivers/dma/bestcomm/bestcomm.c
+++ b/drivers/dma/bestcomm/bestcomm.c
@@ -48,6 +48,7 @@ bcom_task_alloc(int bd_count, int bd_size, int priv_size)
 {
 	int i, tasknum = -1;
 	struct bcom_task *tsk;
+	int irq;
 
 	/* Don't try to do anything if bestcomm init failed */
 	if (!bcom_eng)
@@ -68,6 +69,10 @@ bcom_task_alloc(int bd_count, int bd_size, int priv_size)
 	if (tasknum < 0)
 		return NULL;
 
+	irq = platform_get_irq(bcom_eng->pdev, tasknum);
+	if (irq < 0)
+		return irq;
+
 	/* Allocate our structure */
 	tsk = kzalloc(sizeof(struct bcom_task) + priv_size, GFP_KERNEL);
 	if (!tsk)
@@ -77,10 +82,7 @@ bcom_task_alloc(int bd_count, int bd_size, int priv_size)
 	if (priv_size)
 		tsk->priv = (void*)tsk + sizeof(struct bcom_task);
 
-	/* Get IRQ of that task */
-	tsk->irq = irq_of_parse_and_map(bcom_eng->ofnode, tsk->tasknum);
-	if (!tsk->irq)
-		goto error;
+	tsk->irq = irq;
 
 	/* Init the BDs, if needed */
 	if (bd_count) {
@@ -102,8 +104,6 @@ bcom_task_alloc(int bd_count, int bd_size, int priv_size)
 
 error:
 	if (tsk) {
-		if (tsk->irq)
-			irq_dispose_mapping(tsk->irq);
 		bcom_sram_free(tsk->bd);
 		kfree(tsk->cookie);
 		kfree(tsk);
@@ -126,7 +126,6 @@ bcom_task_free(struct bcom_task *tsk)
 	bcom_eng->tdt[tsk->tasknum].stop  = 0;
 
 	/* Free everything */
-	irq_dispose_mapping(tsk->irq);
 	bcom_sram_free(tsk->bd);
 	kfree(tsk->cookie);
 	kfree(tsk);
@@ -365,23 +364,24 @@ bcom_engine_cleanup(void)
 static int mpc52xx_bcom_probe(struct platform_device *op)
 {
 	struct device_node *ofn_sram;
-	struct resource res_bcom;
+	struct resource *res_bcom;
+	void __iomem *regs;
 
 	int rv;
 
 	/* Inform user we're ok so far */
 	printk(KERN_INFO "DMA: MPC52xx BestComm driver\n");
 
-	/* Get the bestcomm node */
-	of_node_get(op->dev.of_node);
+	regs = devm_platform_get_and_ioremap_resource(op, 0, &res_bcom);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
 
 	/* Prepare SRAM */
 	ofn_sram = of_find_matching_node(NULL, mpc52xx_sram_ids);
 	if (!ofn_sram) {
 		printk(KERN_ERR DRIVER_NAME ": "
 			"No SRAM found in device tree\n");
-		rv = -ENODEV;
-		goto error_ofput;
+		return -ENODEV;
 	}
 	rv = bcom_sram_init(ofn_sram, DRIVER_NAME);
 	of_node_put(ofn_sram);
@@ -389,7 +389,7 @@ static int mpc52xx_bcom_probe(struct platform_device *op)
 	if (rv) {
 		printk(KERN_ERR DRIVER_NAME ": "
 			"Error in SRAM init\n");
-		goto error_ofput;
+		return rv;
 	}
 
 	/* Get a clean struct */
@@ -400,37 +400,14 @@ static int mpc52xx_bcom_probe(struct platform_device *op)
 	}
 
 	/* Save the node */
-	bcom_eng->ofnode = op->dev.of_node;
-
-	/* Get, reserve & map io */
-	if (of_address_to_resource(op->dev.of_node, 0, &res_bcom)) {
-		printk(KERN_ERR DRIVER_NAME ": "
-			"Can't get resource\n");
-		rv = -EINVAL;
-		goto error_sramclean;
-	}
-
-	if (!request_mem_region(res_bcom.start, resource_size(&res_bcom),
-				DRIVER_NAME)) {
-		printk(KERN_ERR DRIVER_NAME ": "
-			"Can't request registers region\n");
-		rv = -EBUSY;
-		goto error_sramclean;
-	}
-
-	bcom_eng->regs_base = res_bcom.start;
-	bcom_eng->regs = ioremap(res_bcom.start, sizeof(struct mpc52xx_sdma));
-	if (!bcom_eng->regs) {
-		printk(KERN_ERR DRIVER_NAME ": "
-			"Can't map registers\n");
-		rv = -ENOMEM;
-		goto error_release;
-	}
+	bcom_eng->pdev = op;
+	bcom_eng->regs = regs;
+	bcom_eng->regs_base = res_bcom->start;
 
 	/* Now, do the real init */
 	rv = bcom_engine_init();
 	if (rv)
-		goto error_unmap;
+		goto error_sramclean;
 
 	/* Done ! */
 	printk(KERN_INFO "DMA: MPC52xx BestComm engine @%08lx ok !\n",
@@ -439,15 +416,9 @@ static int mpc52xx_bcom_probe(struct platform_device *op)
 	return 0;
 
 	/* Error path */
-error_unmap:
-	iounmap(bcom_eng->regs);
-error_release:
-	release_mem_region(res_bcom.start, sizeof(struct mpc52xx_sdma));
 error_sramclean:
 	kfree(bcom_eng);
 	bcom_sram_cleanup();
-error_ofput:
-	of_node_put(op->dev.of_node);
 
 	printk(KERN_ERR "DMA: MPC52xx BestComm init failed !\n");
 
@@ -463,13 +434,6 @@ static void mpc52xx_bcom_remove(struct platform_device *op)
 	/* Cleanup SRAM */
 	bcom_sram_cleanup();
 
-	/* Release regs */
-	iounmap(bcom_eng->regs);
-	release_mem_region(bcom_eng->regs_base, sizeof(struct mpc52xx_sdma));
-
-	/* Release the node */
-	of_node_put(bcom_eng->ofnode);
-
 	/* Release memory */
 	kfree(bcom_eng);
 	bcom_eng = NULL;
diff --git a/include/linux/fsl/bestcomm/bestcomm_priv.h b/include/linux/fsl/bestcomm/bestcomm_priv.h
index 3b52f3ffbdf8..cddde7c74cb5 100644
--- a/include/linux/fsl/bestcomm/bestcomm_priv.h
+++ b/include/linux/fsl/bestcomm/bestcomm_priv.h
@@ -66,7 +66,7 @@ struct bcom_tdt {
  * This holds all info needed globaly to handle the engine
  */
 struct bcom_engine {
-	struct device_node		*ofnode;
+	struct platform_device		*pdev;
 	struct mpc52xx_sdma __iomem     *regs;
 	phys_addr_t                      regs_base;
 
-- 
2.55.0