[PATCH v2 10/22] apple-gmux: Assign apple_gmux_data before registering

[Lukas Wunner]

From: Matthew Garrett <matthew.garrett at nebula.com>

Registering the handler after both GPUs will trigger a DDC switch for
connector reprobing. This will oops if apple_gmux_data hasn't already been
assigned. Reorder the code to do that.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115
Tested-by: Paul Hordiienko <pvt.gord at gmail.com>
    [MBP  6,2 2010  intel ILK + nvidia GT216  pre-retina]
Tested-by: William Brown <william at blackhats.net.au>
    [MBP  8,2 2011  intel SNB + amd turks     pre-retina]
Tested-by: Lukas Wunner <lukas at wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina]
Tested-by: Bruno Bierbaumer <bruno at bierbaumer.net>
    [MBP 11,3 2013  intel HSW + nvidia GK107  retina -- work in progress]

Signed-off-by: Matthew Garrett <matthew.garrett at nebula.com>
Signed-off-by: Lukas Wunner <lukas at wunner.de>
---
 drivers/platform/x86/apple-gmux.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c
index 08bdf1e..b120a11 100644
--- a/drivers/platform/x86/apple-gmux.c
+++ b/drivers/platform/x86/apple-gmux.c
@@ -609,18 +609,20 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
 		gmux_data->gpe = -1;
 	}
 
+	apple_gmux_data = gmux_data;
+	init_completion(&gmux_data->powerchange_done);
+	gmux_enable_interrupts(gmux_data);
+
 	if (vga_switcheroo_register_handler(&gmux_handler)) {
 		ret = -ENODEV;
 		goto err_register_handler;
 	}
 
-	init_completion(&gmux_data->powerchange_done);
-	apple_gmux_data = gmux_data;
-	gmux_enable_interrupts(gmux_data);
-
 	return 0;
 
 err_register_handler:
+	gmux_disable_interrupts(gmux_data);
+	apple_gmux_data = NULL;
 	if (gmux_data->gpe >= 0)
 		acpi_disable_gpe(NULL, gmux_data->gpe);
 err_enable_gpe:
-- 
1.8.5.2 (Apple Git-48)