[PATCH v2 01/32] apple-gmux: Stop using acpi_video_dmi_demote_vendor()

Hans de Goede hdegoede at redhat.com
Fri Jun 12 04:23:20 PDT 2015

acpi_video_dmi_demote_vendor() is going away as part of the cleanup of
the code for determinging which backlight class driver(s) to register.

The call to acpi_video_dmi_demote_vendor() was meant to undo the call to
acpi_video_dmi_promote_vendor() when the gmux device is removed, this is
questionable though since the promote call sets a flag, not a counter, so
the demote call may undo a promoto done elsewhere. Moreover in practice
this is a nop since the gmux device is never removed, and the flag is only
checked when acpi/video.ko gets loaded, so even if the user manually
removes apple-gmux the demote call is still a nop as video.ko will already
have loaded by this time.

Also note that none of the other users of acpi_video_dmi_promote_vendor()
use acpi_video_dmi_demote_vendor().

If we ever encounter a system with a gmux where the acpi-video interface
should be used, then the proper fix would be to dmi-blacklist the gmux
driver on that system.

Signed-off-by: Hans de Goede <hdegoede at redhat.com>
 drivers/platform/x86/apple-gmux.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c
index 45032ce..a7f6412 100644
--- a/drivers/platform/x86/apple-gmux.c
+++ b/drivers/platform/x86/apple-gmux.c
@@ -645,7 +645,6 @@ static void gmux_remove(struct pnp_dev *pnp)
 	apple_gmux_data = NULL;
-	acpi_video_dmi_demote_vendor();

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