amba: tegra-ahb: Fix device leak on SMMU enable

Make sure to drop the reference taken to the AHB platform device when
looking up its driver data while enabling the SMMU.

Note that holding a reference to a device does not prevent its driver
data from going away.

Fixes: 89c788bab1f0 ("ARM: tegra: Add SMMU enabler in AHB")
Cc: stable@vger.kernel.org	# 3.5
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/amba/tegra-ahb.c b/drivers/amba/tegra-ahb.c
index c0e8b765522dc79be3756acf62788812ca6ea7a5..f23c3ed018101c0c29243b8abdd83659a39d3b43 100644 (file)
--- a/drivers/amba/tegra-ahb.c
+++ b/drivers/amba/tegra-ahb.c
@@ -144,6 +144,7 @@ int tegra_ahb_enable_smmu(struct device_node *dn)
        if (!dev)
                return -EPROBE_DEFER;
        ahb = dev_get_drvdata(dev);
+       put_device(dev);
        val = gizmo_readl(ahb, AHB_ARBITRATION_XBAR_CTRL);
        val |= AHB_ARBITRATION_XBAR_CTRL_SMMU_INIT_DONE;
        gizmo_writel(ahb, val, AHB_ARBITRATION_XBAR_CTRL);