On Tue, 20 Jul 2010 21:19:23 +0200 Marcin Slusarz <[email protected]> wrote:
> We don't want vga16fb to mess with hardware initialized by other driver. > Detect it and refuse to load. > It fixes nouveau interrupt storm on some machines. > > Signed-off-by: Marcin Slusarz <[email protected]> > --- > drivers/video/vga16fb.c | 13 ++++++++++++- > 1 files changed, 12 insertions(+), 1 deletions(-) > > diff --git a/drivers/video/vga16fb.c b/drivers/video/vga16fb.c > index 28ccab4..4505446 100644 > --- a/drivers/video/vga16fb.c > +++ b/drivers/video/vga16fb.c > @@ -22,6 +22,7 @@ > #include <linux/platform_device.h> > #include <linux/screen_info.h> > > +#include <asm/fb.h> > #include <asm/io.h> > #include <video/vga.h> > > @@ -1415,7 +1416,7 @@ static struct platform_device *vga16fb_device; > > static int __init vga16fb_init(void) > { > - int ret; > + int ret, i; > #ifndef MODULE > char *option = NULL; > > @@ -1424,6 +1425,16 @@ static int __init vga16fb_init(void) > > vga16fb_setup(option); > #endif > + for (i = 0 ; i < FB_MAX; i++) { > + if (!registered_fb[i]) > + continue; > + if (fb_is_primary_device(registered_fb[i])) { > + printk(KERN_INFO "vga16fb: %s is driving the primary > card, refusing to load\n", > + registered_fb[i]->fix.id); > + return -EBUSY; > + } > + } > + > ret = platform_driver_register(&vga16fb_driver); > > if (!ret) { This seems pretty hacky, and specific to vga16fb. Is vga16fb.c the only fbdev driver (now and forever more) which can grab the hardware from under a different driver's feet? This is the basic and very common problem of two drivers diddling the same hardware, yes? A common way of preventing such collisions is to perform a suitably-checked request_region() in both drivers. Whichever driver gets there second will get a failure and will bale out cleanly. Can that mechanism be made to work in this case? _______________________________________________ Nouveau mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/nouveau
