diff options
Diffstat (limited to 'drivers/video/fbdev')
| -rw-r--r-- | drivers/video/fbdev/core/fbmem.c | 47 | ||||
| -rw-r--r-- | drivers/video/fbdev/efifb.c | 11 | ||||
| -rw-r--r-- | drivers/video/fbdev/simplefb.c | 11 | ||||
| -rw-r--r-- | drivers/video/fbdev/xen-fbfront.c | 1 |
4 files changed, 70 insertions, 0 deletions
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index 826175ad88a2..0fa7ede94fa6 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1763,6 +1763,53 @@ int remove_conflicting_framebuffers(struct apertures_struct *a, EXPORT_SYMBOL(remove_conflicting_framebuffers); /** + * is_firmware_framebuffer - detect if firmware-configured framebuffer matches + * @a: memory range, users of which are to be checked + * + * This function checks framebuffer devices (initialized by firmware/bootloader) + * which use memory range described by @a. If @a matchesm the function returns + * true, otherwise false. + */ +bool is_firmware_framebuffer(struct apertures_struct *a) +{ + bool do_free = false; + bool found = false; + int i; + + if (!a) { + a = alloc_apertures(1); + if (!a) + return false; + + a->ranges[0].base = 0; + a->ranges[0].size = ~0; + do_free = true; + } + + mutex_lock(®istration_lock); + /* check all firmware fbs and kick off if the base addr overlaps */ + for_each_registered_fb(i) { + struct apertures_struct *gen_aper; + + if (!(registered_fb[i]->flags & FBINFO_MISC_FIRMWARE)) + continue; + + gen_aper = registered_fb[i]->apertures; + if (fb_do_apertures_overlap(gen_aper, a)) { + found = true; + break; + } + } + mutex_unlock(®istration_lock); + + if (do_free) + kfree(a); + + return found; +} +EXPORT_SYMBOL(is_firmware_framebuffer); + +/** * remove_conflicting_pci_framebuffers - remove firmware-configured framebuffers for PCI devices * @pdev: PCI device * @name: requesting driver name diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c index edca3703b964..ea42ba6445b2 100644 --- a/drivers/video/fbdev/efifb.c +++ b/drivers/video/fbdev/efifb.c @@ -351,6 +351,17 @@ static int efifb_probe(struct platform_device *dev) char *option = NULL; efi_memory_desc_t md; + /* + * Generic drivers must not be registered if a framebuffer exists. + * If a native driver was probed, the display hardware was already + * taken and attempting to use the system framebuffer is dangerous. + */ + if (num_registered_fb > 0) { + dev_err(&dev->dev, + "efifb: a framebuffer is already registered\n"); + return -EINVAL; + } + if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI || pci_dev_disabled) return -ENODEV; diff --git a/drivers/video/fbdev/simplefb.c b/drivers/video/fbdev/simplefb.c index 62f0ded70681..b63074fd892e 100644 --- a/drivers/video/fbdev/simplefb.c +++ b/drivers/video/fbdev/simplefb.c @@ -407,6 +407,17 @@ static int simplefb_probe(struct platform_device *pdev) struct simplefb_par *par; struct resource *mem; + /* + * Generic drivers must not be registered if a framebuffer exists. + * If a native driver was probed, the display hardware was already + * taken and attempting to use the system framebuffer is dangerous. + */ + if (num_registered_fb > 0) { + dev_err(&pdev->dev, + "simplefb: a framebuffer is already registered\n"); + return -EINVAL; + } + if (fb_get_options("simplefb", NULL)) return -ENODEV; diff --git a/drivers/video/fbdev/xen-fbfront.c b/drivers/video/fbdev/xen-fbfront.c index 5ec51445bee8..6826f986da43 100644 --- a/drivers/video/fbdev/xen-fbfront.c +++ b/drivers/video/fbdev/xen-fbfront.c @@ -695,6 +695,7 @@ static struct xenbus_driver xenfb_driver = { .remove = xenfb_remove, .resume = xenfb_resume, .otherend_changed = xenfb_backend_changed, + .not_essential = true, }; static int __init xenfb_init(void) |