Re: [PATCH v2] grvga: Fix error handling issues
From: Florian Tobias Schandinat
Date: Sun Jul 08 2012 - 18:02:33 EST
On 06/25/2012 10:37 PM, Emil Goode wrote:
> This patch fixes two problems with the error handling in the
> grvga_probe function and simplifies it making the code
> easier to read.
>
> - If the call to grvga_parse_custom on line 370 fails we use
> the wrong label so that release_mem_region will be called
> without a call to request_mem_region being made.
>
> - If the call to ioremap on line 436 fails we should not try
> to call iounmap in the error handling code.
>
> This patch introduces the following changes:
>
> - Converts request_mem_region into its devm_ equivalent
> which simplifies the otherwise messy clean up code.
>
> - Changes the labels for correct error handling and their
> names to make the code easier to read.
>
> Signed-off-by: Emil Goode <emilgoode@xxxxxxxxx>
Applied.
Thanks,
Florian Tobias Schandinat
> ---
> v2: Simplifies the error handling by converting to
> devm_request_mem_region
>
> drivers/video/grvga.c | 47 ++++++++++++++++++++++-------------------------
> 1 file changed, 22 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/video/grvga.c b/drivers/video/grvga.c
> index da066c2..5245f9a 100644
> --- a/drivers/video/grvga.c
> +++ b/drivers/video/grvga.c
> @@ -354,7 +354,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> */
> if (fb_get_options("grvga", &options)) {
> retval = -ENODEV;
> - goto err;
> + goto free_fb;
> }
>
> if (!options || !*options)
> @@ -370,7 +370,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> if (grvga_parse_custom(this_opt, &info->var) < 0) {
> dev_err(&dev->dev, "Failed to parse custom mode (%s).\n", this_opt);
> retval = -EINVAL;
> - goto err1;
> + goto free_fb;
> }
> } else if (!strncmp(this_opt, "addr", 4))
> grvga_fix_addr = simple_strtoul(this_opt + 5, NULL, 16);
> @@ -387,10 +387,11 @@ static int __devinit grvga_probe(struct platform_device *dev)
> info->flags = FBINFO_DEFAULT | FBINFO_PARTIAL_PAN_OK | FBINFO_HWACCEL_YPAN;
> info->fix.smem_len = grvga_mem_size;
>
> - if (!request_mem_region(dev->resource[0].start, resource_size(&dev->resource[0]), "grlib-svgactrl regs")) {
> + if (!devm_request_mem_region(&dev->dev, dev->resource[0].start,
> + resource_size(&dev->resource[0]), "grlib-svgactrl regs")) {
> dev_err(&dev->dev, "registers already mapped\n");
> retval = -EBUSY;
> - goto err;
> + goto free_fb;
> }
>
> par->regs = of_ioremap(&dev->resource[0], 0,
> @@ -400,14 +401,14 @@ static int __devinit grvga_probe(struct platform_device *dev)
> if (!par->regs) {
> dev_err(&dev->dev, "failed to map registers\n");
> retval = -ENOMEM;
> - goto err1;
> + goto free_fb;
> }
>
> retval = fb_alloc_cmap(&info->cmap, 256, 0);
> if (retval < 0) {
> dev_err(&dev->dev, "failed to allocate mem with fb_alloc_cmap\n");
> retval = -ENOMEM;
> - goto err2;
> + goto unmap_regs;
> }
>
> if (mode_opt) {
> @@ -415,7 +416,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> grvga_modedb, sizeof(grvga_modedb), &grvga_modedb[0], 8);
> if (!retval || retval == 4) {
> retval = -EINVAL;
> - goto err3;
> + goto dealloc_cmap;
> }
> }
>
> @@ -427,10 +428,11 @@ static int __devinit grvga_probe(struct platform_device *dev)
>
> physical_start = grvga_fix_addr;
>
> - if (!request_mem_region(physical_start, grvga_mem_size, dev->name)) {
> + if (!devm_request_mem_region(&dev->dev, physical_start,
> + grvga_mem_size, dev->name)) {
> dev_err(&dev->dev, "failed to request memory region\n");
> retval = -ENOMEM;
> - goto err3;
> + goto dealloc_cmap;
> }
>
> virtual_start = (unsigned long) ioremap(physical_start, grvga_mem_size);
> @@ -438,7 +440,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> if (!virtual_start) {
> dev_err(&dev->dev, "error mapping framebuffer memory\n");
> retval = -ENOMEM;
> - goto err4;
> + goto dealloc_cmap;
> }
> } else { /* Allocate frambuffer memory */
>
> @@ -451,7 +453,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> "unable to allocate framebuffer memory (%lu bytes)\n",
> grvga_mem_size);
> retval = -ENOMEM;
> - goto err3;
> + goto dealloc_cmap;
> }
>
> physical_start = dma_map_single(&dev->dev, (void *)virtual_start, grvga_mem_size, DMA_TO_DEVICE);
> @@ -484,7 +486,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> retval = register_framebuffer(info);
> if (retval < 0) {
> dev_err(&dev->dev, "failed to register framebuffer\n");
> - goto err4;
> + goto free_mem;
> }
>
> __raw_writel(physical_start, &par->regs->fb_pos);
> @@ -493,21 +495,18 @@ static int __devinit grvga_probe(struct platform_device *dev)
>
> return 0;
>
> -err4:
> +free_mem:
> dev_set_drvdata(&dev->dev, NULL);
> - if (grvga_fix_addr) {
> - release_mem_region(physical_start, grvga_mem_size);
> + if (grvga_fix_addr)
> iounmap((void *)virtual_start);
> - } else
> + else
> kfree((void *)virtual_start);
> -err3:
> +dealloc_cmap:
> fb_dealloc_cmap(&info->cmap);
> -err2:
> +unmap_regs:
> of_iounmap(&dev->resource[0], par->regs,
> resource_size(&dev->resource[0]));
> -err1:
> - release_mem_region(dev->resource[0].start, resource_size(&dev->resource[0]));
> -err:
> +free_fb:
> framebuffer_release(info);
>
> return retval;
> @@ -524,12 +523,10 @@ static int __devexit grvga_remove(struct platform_device *device)
>
> of_iounmap(&device->resource[0], par->regs,
> resource_size(&device->resource[0]));
> - release_mem_region(device->resource[0].start, resource_size(&device->resource[0]));
>
> - if (!par->fb_alloced) {
> - release_mem_region(info->fix.smem_start, info->fix.smem_len);
> + if (!par->fb_alloced)
> iounmap(info->screen_base);
> - } else
> + else
> kfree((void *)info->screen_base);
>
> framebuffer_release(info);
--
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