From: "Maciej W. Rozycki" Add error messages to the probe call. While they may rarely trigger, they may be useful when something weird is going on. Also this is good style. Signed-off-by: Maciej W. Rozycki Cc: Mariusz Kozlowski Cc: Ralf Baechle Cc: "Antonino A. Daplas" Signed-off-by: Andrew Morton --- drivers/video/pmag-ba-fb.c | 34 +++++++++++++++++++++++++++------- 1 files changed, 27 insertions(+), 7 deletions(-) diff -puN drivers/video/pmag-ba-fb.c~drivers-video-pmag-ba-fbc-improve-diagnostics drivers/video/pmag-ba-fb.c --- a/drivers/video/pmag-ba-fb.c~drivers-video-pmag-ba-fbc-improve-diagnostics +++ a/drivers/video/pmag-ba-fb.c @@ -147,16 +147,23 @@ static int __init pmagbafb_probe(struct resource_size_t start, len; struct fb_info *info; struct pmagbafb_par *par; + int err = 0; info = framebuffer_alloc(sizeof(struct pmagbafb_par), dev); - if (!info) + if (!info) { + printk(KERN_ERR "%s: Cannot allocate memory\n", dev->bus_id); return -ENOMEM; + } par = info->par; dev_set_drvdata(dev, info); - if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) + if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) { + printk(KERN_ERR "%s: Cannot allocate color map\n", + dev->bus_id); + err = -ENOMEM; goto err_alloc; + } info->fbops = &pmagbafb_ops; info->fix = pmagbafb_fix; @@ -166,28 +173,41 @@ static int __init pmagbafb_probe(struct /* Request the I/O MEM resource. */ start = tdev->resource.start; len = tdev->resource.end - start + 1; - if (!request_mem_region(start, len, dev->bus_id)) + if (!request_mem_region(start, len, dev->bus_id)) { + printk(KERN_ERR "%s: Cannot reserve FB region\n", dev->bus_id); + err = -EBUSY; goto err_cmap; + } /* MMIO mapping setup. */ info->fix.mmio_start = start; par->mmio = ioremap_nocache(info->fix.mmio_start, info->fix.mmio_len); - if (!par->mmio) + if (!par->mmio) { + printk(KERN_ERR "%s: Cannot map MMIO\n", dev->bus_id); + err = -ENOMEM; goto err_resource; + } par->dac = par->mmio + PMAG_BA_BT459; /* Frame buffer mapping setup. */ info->fix.smem_start = start + PMAG_BA_FBMEM; info->screen_base = ioremap_nocache(info->fix.smem_start, info->fix.smem_len); - if (!info->screen_base) + if (!info->screen_base) { + printk(KERN_ERR "%s: Cannot map FB\n", dev->bus_id); + err = -ENOMEM; goto err_mmio_map; + } info->screen_size = info->fix.smem_len; pmagbafb_erase_cursor(info); - if (register_framebuffer(info) < 0) + err = register_framebuffer(info); + if (err < 0) { + printk(KERN_ERR "%s: Cannot register framebuffer\n", + dev->bus_id); goto err_smem_map; + } get_device(dev); @@ -211,7 +231,7 @@ err_cmap: err_alloc: framebuffer_release(info); - return -ENXIO; + return err; } static int __exit pmagbafb_remove(struct device *dev) _