[PATCH v3] mtd: plat-ram: Replace manual resource management by devm

From: Anton Vasilyev
Date: Tue Aug 22 2017 - 09:25:10 EST


Driver contains unsuitable request_mem_region() and
release_resource() calls.

The patch switches manual resource management by devm interface for
readability and error-free simplification.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Anton Vasilyev <vasilyev@xxxxxxxxx>
Suggested-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
---
v1: Fix commit based on Boris Brezillon review
---
v2: Change commit by Boris Brezillon solution
---
v3: Change description with title
---
drivers/mtd/maps/plat-ram.c | 38 ++++----------------------------------
1 file changed, 4 insertions(+), 34 deletions(-)

diff --git a/drivers/mtd/maps/plat-ram.c b/drivers/mtd/maps/plat-ram.c
index 5157289..6d9a4d6 100644
--- a/drivers/mtd/maps/plat-ram.c
+++ b/drivers/mtd/maps/plat-ram.c
@@ -43,7 +43,6 @@ struct platram_info {
struct device *dev;
struct mtd_info *mtd;
struct map_info map;
- struct resource *area;
struct platdata_mtd_ram *pdata;
};

@@ -97,16 +96,6 @@ static int platram_remove(struct platform_device *pdev)

platram_setrw(info, PLATRAM_RO);

- /* release resources */
-
- if (info->area) {
- release_resource(info->area);
- kfree(info->area);
- }
-
- if (info->map.virt != NULL)
- iounmap(info->map.virt);
-
kfree(info);

return 0;
@@ -147,12 +136,11 @@ static int platram_probe(struct platform_device *pdev)
info->pdata = pdata;

/* get the resource for the memory mapping */
-
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-
- if (res == NULL) {
- dev_err(&pdev->dev, "no memory resource specified\n");
- err = -ENOENT;
+ info->map.virt = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(info->map.virt)) {
+ err = PTR_ERR(info->map.virt);
+ dev_err(&pdev->dev, "failed to ioremap() region\n");
goto exit_free;
}

@@ -167,26 +155,8 @@ static int platram_probe(struct platform_device *pdev)
(char *)pdata->mapname : (char *)pdev->name;
info->map.bankwidth = pdata->bankwidth;

- /* register our usage of the memory area */
-
- info->area = request_mem_region(res->start, info->map.size, pdev->name);
- if (info->area == NULL) {
- dev_err(&pdev->dev, "failed to request memory region\n");
- err = -EIO;
- goto exit_free;
- }
-
- /* remap the memory area */
-
- info->map.virt = ioremap(res->start, info->map.size);
dev_dbg(&pdev->dev, "virt %p, %lu bytes\n", info->map.virt, info->map.size);

- if (info->map.virt == NULL) {
- dev_err(&pdev->dev, "failed to ioremap() region\n");
- err = -EIO;
- goto exit_free;
- }
-
simple_map_init(&info->map);

dev_dbg(&pdev->dev, "initialised map, probing for mtd\n");
--
2.7.4