[PATCH RESEND] drm/tegra: dc: fix reference leak in tegra_dc_couple()

[Ma Ke <make24@iscas.ac.cn>]

driver_find_device() calls get_device() to increment the reference
count once a matching device is found, but there is no put_device() to
balance the reference count. To avoid reference count leakage, add
put_device() to decrease the reference count.

Found by code review.

Cc: stable@vger.kernel.org
Fixes: a31500fe7055 ("drm/tegra: dc: Restore coupling of display controllers")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
---
 drivers/gpu/drm/tegra/dc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index 59d5c1ba145a..6c84bd69b11f 100644
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -3148,6 +3148,7 @@ static int tegra_dc_couple(struct tegra_dc *dc)
 		dc->client.parent = &parent->client;
 
 		dev_dbg(dc->dev, "coupled to %s\n", dev_name(companion));
+		put_device(companion);
 	}
 
 	return 0;
-- 
2.17.1