Re: [Intel-gfx] [PATCH v3] ACPI / video: Add systems that should favor native backlight interface
On Tue, 2014-01-21 at 13:32 +0800, Aaron Lu wrote: On 01/21/2014 11:17 AM, Matthew Garrett wrote: We know that Windows 8 graphics drivers don't use the ACPI interface, and that systems change their behaviour as a result, in some cases with absolutely no way for the ACPI interface could possibly work. I haven't seen any cases where that's obviously true for any non-Windows 8 Perhaps I'm not clear, I didn't mean non-Windows 8 systems will all favor GPU's interface, I just meant for one specific win7 laptop I could re-use the existing code to make the GPU's interface as the only one left. And to achieve this, the Win8 OSI check in acpi_video_verify_backlight_support has to be gone. We could do that, but why do we think that's the correct fix? The plan is to remove the native list entirely and do this for all Windows 8 systems, so the Win8 OSI check is the right thing to do. -- Matthew Garrett matthew.garr...@nebula.com ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH v3] ACPI / video: Add systems that should favor native backlight interface
On Mon, 2014-01-20 at 16:12 +0800, Aaron Lu wrote: 1 remove the win8 OSI check, I've seen win7 laptops that also needs to have only the GPU interface left and checking win8 doesn't make much sense now; Are we sure that those aren't simply some other bug? -- Matthew Garrett matthew.garr...@nebula.com ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH v3] ACPI / video: Add systems that should favor native backlight interface
On Tue, 2014-01-21 at 10:24 +0800, Aaron Lu wrote: On 01/20/2014 09:34 PM, Matthew Garrett wrote: On Mon, 2014-01-20 at 16:12 +0800, Aaron Lu wrote: 1 remove the win8 OSI check, I've seen win7 laptops that also needs to have only the GPU interface left and checking win8 doesn't make much sense now; Are we sure that those aren't simply some other bug? Well, the firmware on that laptop makes use of EC to do backlight control and the fact that the firmware interface doesn't work while the GPU's work seems to indicate that the backlight control circuit is not routed to EC. I think this is the same case as Win8 laptops. We know that Windows 8 graphics drivers don't use the ACPI interface, and that systems change their behaviour as a result, in some cases with absolutely no way for the ACPI interface could possibly work. I haven't seen any cases where that's obviously true for any non-Windows 8 systems. EC interfaces that don't work are often due to Linux leaving the hardware in a state other than the one expected by the firmware. We shouldn't assume that it's the same issue until we've investigated further. -- Matthew Garrett matthew.garr...@nebula.com ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH v3] ACPI / video: Add systems that should favor native backlight interface
On 01/21/2014 11:17 AM, Matthew Garrett wrote: On Tue, 2014-01-21 at 10:24 +0800, Aaron Lu wrote: On 01/20/2014 09:34 PM, Matthew Garrett wrote: On Mon, 2014-01-20 at 16:12 +0800, Aaron Lu wrote: 1 remove the win8 OSI check, I've seen win7 laptops that also needs to have only the GPU interface left and checking win8 doesn't make much sense now; Are we sure that those aren't simply some other bug? Well, the firmware on that laptop makes use of EC to do backlight control and the fact that the firmware interface doesn't work while the GPU's work seems to indicate that the backlight control circuit is not routed to EC. I think this is the same case as Win8 laptops. We know that Windows 8 graphics drivers don't use the ACPI interface, and that systems change their behaviour as a result, in some cases with absolutely no way for the ACPI interface could possibly work. I haven't seen any cases where that's obviously true for any non-Windows 8 Perhaps I'm not clear, I didn't mean non-Windows 8 systems will all favor GPU's interface, I just meant for one specific win7 laptop I could re-use the existing code to make the GPU's interface as the only one left. And to achieve this, the Win8 OSI check in acpi_video_verify_backlight_support has to be gone. BTW, I actually think use_native_backlight param should mean the native backlight control interface will be the only one available on the system, it doesn't need to go side by side with Win8 OSI check. systems. EC interfaces that don't work are often due to Linux leaving the hardware in a state other than the one expected by the firmware. We Good to know this, thanks. shouldn't assume that it's the same issue until we've investigated further. OK, but I honestly don't have any idea how to proceed, in case you have some time, the bug is: https://bugzilla.kernel.org/show_bug.cgi?id=66501 ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
