commit: ce880cb860f36694d2cdebfac9e6ae18176fe4c4 From: Kay Sievers <[email protected]> Date: Sat, 28 Jan 2012 19:57:46 +0000 Subject: udlfb: remove sysfs framebuffer device with USB .disconnect()
The USB graphics card driver delays the unregistering of the framebuffer device to a workqueue, which breaks the userspace visible remove uevent sequence. Recent userspace tools started to support USB graphics card hotplug out-of-the-box and rely on proper events sent by the kernel. The framebuffer device is a direct child of the USB interface which is removed immediately after the USB .disconnect() callback. But the fb device in /sys stays around until its final cleanup, at a time where all the parent devices have been removed already. To work around that, we remove the sysfs fb device directly in the USB .disconnect() callback and leave only the cleanup of the internal fb data to the delayed work. Before: add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2 (usb) add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0 (usb) add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/graphics/fb0 (graphics) remove /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0 (usb) remove /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2 (usb) remove /2-1.2:1.0/graphics/fb0 (graphics) After: add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2 (usb) add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0 (usb) add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/graphics/fb1 (graphics) remove /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/graphics/fb1 (graphics) remove /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0 (usb) remove /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2 (usb) Cc: [email protected] Tested-by: Bernie Thompson <[email protected]> Acked-by: Bernie Thompson <[email protected]> Signed-off-by: Kay Sievers <[email protected]> Signed-off-by: Florian Tobias Schandinat <[email protected]> --- drivers/video/fbmem.c | 18 +++++++++++++++++- drivers/video/udlfb.c | 2 +- include/linux/fb.h | 1 + 3 files changed, 19 insertions(+), 2 deletions(-) diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c index ac9141b..c6ce416 100644 --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -1665,6 +1665,7 @@ static int do_unregister_framebuffer(struct fb_info *fb_info) if (ret) return -EINVAL; + unlink_framebuffer(fb_info); if (fb_info->pixmap.addr && (fb_info->pixmap.flags & FB_PIXMAP_DEFAULT)) kfree(fb_info->pixmap.addr); @@ -1672,7 +1673,6 @@ static int do_unregister_framebuffer(struct fb_info *fb_info) registered_fb[i] = NULL; num_registered_fb--; fb_cleanup_device(fb_info); - device_destroy(fb_class, MKDEV(FB_MAJOR, i)); event.info = fb_info; fb_notifier_call_chain(FB_EVENT_FB_UNREGISTERED, &event); @@ -1681,6 +1681,22 @@ static int do_unregister_framebuffer(struct fb_info *fb_info) return 0; } +int unlink_framebuffer(struct fb_info *fb_info) +{ + int i; + + i = fb_info->node; + if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info) + return -EINVAL; + + if (fb_info->dev) { + device_destroy(fb_class, MKDEV(FB_MAJOR, i)); + fb_info->dev = NULL; + } + return 0; +} +EXPORT_SYMBOL(unlink_framebuffer); + void remove_conflicting_framebuffers(struct apertures_struct *a, const char *name, bool primary) { diff --git a/drivers/video/udlfb.c b/drivers/video/udlfb.c index a197731..a40c05e 100644 --- a/drivers/video/udlfb.c +++ b/drivers/video/udlfb.c @@ -1739,7 +1739,7 @@ static void dlfb_usb_disconnect(struct usb_interface *interface) for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) device_remove_file(info->dev, &fb_device_attrs[i]); device_remove_bin_file(info->dev, &edid_attr); - + unlink_framebuffer(info); usb_set_intfdata(interface, NULL); /* if clients still have us open, will be freed on last close */ diff --git a/include/linux/fb.h b/include/linux/fb.h index c18122f..a395b8c 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -1003,6 +1003,7 @@ extern ssize_t fb_sys_write(struct fb_info *info, const char __user *buf, /* drivers/video/fbmem.c */ extern int register_framebuffer(struct fb_info *fb_info); extern int unregister_framebuffer(struct fb_info *fb_info); +extern int unlink_framebuffer(struct fb_info *fb_info); extern void remove_conflicting_framebuffers(struct apertures_struct *a, const char *name, bool primary); extern int fb_prepare_logo(struct fb_info *fb_info, int rotate); -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
