On Thu, Mar 05, 2015 at 11:20:38PM +0100, Bruno Prémont wrote: > As GMUX depends on IO for iGP to be enabled and active, lock the IO at > vgaarb level. This should prevent GPU driver for dGPU to disable IO for > iGP while it tries to own legacy VGA IO. > > This fixes usage of backlight control combined with closed nvidia > driver on some Apple dual-GPU (intel/nvidia) systems. > > On those systems loading nvidia driver disables intel IO decoding, > disabling the gmux backlight controls as a side effect. > Prior to commits moving boot_vga from (optional) efifb to less optional > vgaarb this mis-behavior could be avoided by using right kernel config > (efifb enabled but vgaarb disabled). > > This patch explicitly does not try to trigger vgaarb changes in order > to avoid confusing already running graphics drivers. If IO has been > mis-configured by vgaarb gmux will thus fail to probe. > It is expected to load/probe gmux prior to graphics drivers. > > Fixes: ce027dac592c0ada241ce0f95ae65856828ac450 # nvidia interaction > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=86121 > Reported-by: Petri Hodju <petrihodju@xxxxxxxxx> > Tested-by: Petri Hodju <petrihodju@xxxxxxxxx> > Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > Cc: Matthew Garrett <matthew.garrett@xxxxxxxxxx> > Signed-off-by: Bruno Prémont <bonbons@xxxxxxxxxxxxxxxxx> > --- > Respinning, fixing Darren's nit. > > Changes since v1: > - Dropped repeat of gmux in pr_info/pr_err calls > - Mention PCI device we tried to lock IO for in case of error Hi Bruno, I don't know if this is on your end or mine (I've not seen this before). Saving off your patch (through mutt like I do everything else) to a file and applying works, build works, and git show and visual inspection look correct. However, checkpatch sees a lot of =3D instead of just =, and complains bitterly. Can you check this patch (from the list) and let me know what you find? ERROR: patch seems to be corrupt (line wrapped?) #93: FILE: drivers/platform/x86/apple-gmux.c:27: =20 ERROR: spaces required around that '=' (ctx:WxV) #108: FILE: drivers/platform/x86/apple-gmux.c:421: + struct pci_dev *pdev =3D NULL; ^ WARNING: Missing a blank line after declarations #109: FILE: drivers/platform/x86/apple-gmux.c:422: + struct pci_dev *pdev =3D NULL; + while ((pdev =3D pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev))) { ERROR: spaces required around that '=' (ctx:WxV) #109: FILE: drivers/platform/x86/apple-gmux.c:422: + while ((pdev =3D pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev))) { ^ ERROR: spaces required around that '=' (ctx:WxV) #130: FILE: drivers/platform/x86/apple-gmux.c:447: + struct pci_dev *pdev =3D NULL; ^ ERROR: spaces required around that '=' (ctx:WxV) #155: FILE: drivers/platform/x86/apple-gmux.c:510: + pdev =3D gmux_find_pdev(); ^ ERROR: spaces required around that '=' (ctx:WxV) #160: FILE: drivers/platform/x86/apple-gmux.c:515: + ret =3D -EBUSY; ^ ERROR: need consistent spacing around '-' (ctx:WxV) #160: FILE: drivers/platform/x86/apple-gmux.c:515: + ret =3D -EBUSY; ^ ERROR: spaces required around that '=' (ctx:WxV) #164: FILE: drivers/platform/x86/apple-gmux.c:519: + gmux_data->pdev =3D pdev; ^ total: 8 errors, 1 warnings, 96 lines checked /home/dvhart/apple.patch has style problems, please review. If any of these errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. -- Darren Hart Intel Open Source Technology Center -- 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
