Dear Corentin, Yes, you are right, finally I know the story, thank you very much. There is an udev event sending out while pressing the brightness key. I'll file a bug for gnome-settings-daemon, since we use it to handle the OSD. And please ignore this patch, I'll resend it with quirks. If you are still interesting in the DSDT, here you are. Thanks. Best regards, AceLan Kao. 2012/3/12 Corentin Chary <corentin.chary@xxxxxxxxx>: > On Mon, Mar 12, 2012 at 2:34 AM, AceLan Kao <acelan.kao@xxxxxxxxxxxxx> wrote: >> Dear Corentin, >> >> No, I don't use acpi_backlight=vendor or something like that. >> And there is no ACPI backlight functions in the BIOS. > > Hum ok, I see. I would be curious to take a look at the DSDT, is this possible ? > >> Yes, we just need to inform the userspace to update the backlight >> brightness status, and I found that using backlight_notify doesn't work, so I let it send >> the key event directly. > > Here is how backlight notification work these days: > > When a backlight related hotkey is received: > - The BIOS already have handled it and changed the brightness: we have > to call backlight_force_update(bd, BACKLIGHT_UPDATE_HOTKEY) to tell > userspace that the brightness have changed in response to an hotkey > - The BIOS haven't handled it: we should only send an input event > (KEY_BRIGHTNESSDOWN or KEY_BRIGHTNESSUP) and userspace will deal with > it (setting the appropriate sysfs file, and displaying an OSD). > > When we call backlight_force_update(bd, BACKLIGHT_UPDATE_HOTKEY), it > do two things: > - send a change notification on the actual_brightness file (userspace > can monitor it using inotify or related). > - send a uevent which can be catched by udev or others (with SOURCE > being an env variable containing the source of this change). > > It's possible that some desktop components don't handle that correctly > yet (gnome-power-daemon, gnome-settings-daemon, powerdevil, xrandr, > etc..). But in this case you should send them a bug report. > > ref: backlight: Allow drivers to update the core, and generate events > on changes - https://lwn.net/Articles/341289/ > > -- > Corentin Chary > http://xf.iksaif.net > -- > To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Chia-Lin Kao(AceLan) http://blog.acelan.idv.tw/ E-Mail: acelan.kaoATcanonical.com (s/AT/@/)
DSDTÝ–