grvga: Fix error handling issues

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@gmail.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>

diff --git a/drivers/video/grvga.c b/drivers/video/grvga.c
index da066c2..5245f9a 100644 (file)
--- 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);