[PATCHv5] dmaengine: bestcomm: use devm_platform_get_and_ioremap_resource() to simplify code
From: Rosen Penev <hidden>
Date: 2026-09-15 07:28:55
Also in:
lkml
Subsystem:
dma generic offload engine subsystem, the rest · Maintainers:
Vinod Koul, Linus Torvalds
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 probing. Fix a resource size mismatch between allocating and freeing where request_mem_region() and release_mem_region() hopefully use the same size but is not guarenteed. Signed-off-by: Rosen Penev <redacted> --- v5: resend with PATCHv5 this time. v4: fix subject v3: reword again v2: remove Sashiko generated description. Reword description. drivers/dma/bestcomm/bestcomm.c | 45 ++++++++------------------------- 1 file changed, 10 insertions(+), 35 deletions(-)
diff --git a/drivers/dma/bestcomm/bestcomm.c b/drivers/dma/bestcomm/bestcomm.c
index ec58d2c6573f..241a91936fe8 100644
--- a/drivers/dma/bestcomm/bestcomm.c
+++ b/drivers/dma/bestcomm/bestcomm.c@@ -13,7 +13,6 @@ #include <linux/kernel.h> #include <linux/slab.h> #include <linux/of.h> -#include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/platform_device.h> #include <asm/io.h>
@@ -365,13 +364,19 @@ 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, reserve & map io */ + regs = devm_platform_get_and_ioremap_resource(op, 0, &res_bcom); + if (IS_ERR(regs)) + return PTR_ERR(regs); + /* Get the bestcomm node */ of_node_get(op->dev.of_node);
@@ -402,35 +407,13 @@ 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->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",
@@ -439,10 +422,6 @@ 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_eng = NULL;
@@ -464,10 +443,6 @@ 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);
--
2.55.0