[PATCH] drm/nouveau: platform: Fix deferred probe

[Thierry Reding]

From: Thierry Reding <tred...@nvidia.com>

The error cleanup paths aren't quite correct and will crash upon
deferred probe.

Cc: stable at vger.kernel.org # v4.3+
Signed-off-by: Thierry Reding <treding at nvidia.com>
---
 drivers/gpu/drm/nouveau/nouveau_platform.c         |  2 +-
 drivers/gpu/drm/nouveau/nvkm/engine/device/tegra.c | 40 ++++++++++++++++------
 2 files changed, 30 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_platform.c 
b/drivers/gpu/drm/nouveau/nouveau_platform.c
index 8a70cec59bcd..2dfe58af12e4 100644
--- a/drivers/gpu/drm/nouveau/nouveau_platform.c
+++ b/drivers/gpu/drm/nouveau/nouveau_platform.c
@@ -24,7 +24,7 @@
 static int nouveau_platform_probe(struct platform_device *pdev)
 {
        const struct nvkm_device_tegra_func *func;
-       struct nvkm_device *device;
+       struct nvkm_device *device = NULL;
        struct drm_device *drm;
        int ret;

diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/device/tegra.c 
b/drivers/gpu/drm/nouveau/nvkm/engine/device/tegra.c
index 7f8a42721eb2..e7e581d6a8ff 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/device/tegra.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/device/tegra.c
@@ -252,32 +252,40 @@ nvkm_device_tegra_new(const struct nvkm_device_tegra_func 
*func,

        if (!(tdev = kzalloc(sizeof(*tdev), GFP_KERNEL)))
                return -ENOMEM;
-       *pdevice = &tdev->device;
+
        tdev->func = func;
        tdev->pdev = pdev;
        tdev->irq = -1;

        tdev->vdd = devm_regulator_get(&pdev->dev, "vdd");
-       if (IS_ERR(tdev->vdd))
-               return PTR_ERR(tdev->vdd);
+       if (IS_ERR(tdev->vdd)) {
+               ret = PTR_ERR(tdev->vdd);
+               goto free;
+       }

        tdev->rst = devm_reset_control_get(&pdev->dev, "gpu");
-       if (IS_ERR(tdev->rst))
-               return PTR_ERR(tdev->rst);
+       if (IS_ERR(tdev->rst)) {
+               ret = PTR_ERR(tdev->rst);
+               goto free;
+       }

        tdev->clk = devm_clk_get(&pdev->dev, "gpu");
-       if (IS_ERR(tdev->clk))
-               return PTR_ERR(tdev->clk);
+       if (IS_ERR(tdev->clk)) {
+               ret = PTR_ERR(tdev->clk);
+               goto free;
+       }

        tdev->clk_pwr = devm_clk_get(&pdev->dev, "pwr");
-       if (IS_ERR(tdev->clk_pwr))
-               return PTR_ERR(tdev->clk_pwr);
+       if (IS_ERR(tdev->clk_pwr)) {
+               ret = PTR_ERR(tdev->clk_pwr);
+               goto free;
+       }

        nvkm_device_tegra_probe_iommu(tdev);

        ret = nvkm_device_tegra_power_up(tdev);
        if (ret)
-               return ret;
+               goto remove;

        tdev->gpu_speedo = tegra_sku_info.gpu_speedo_value;
        ret = nvkm_device_ctor(&nvkm_device_tegra_func, NULL, &pdev->dev,
@@ -285,9 +293,19 @@ nvkm_device_tegra_new(const struct nvkm_device_tegra_func 
*func,
                               cfg, dbg, detect, mmio, subdev_mask,
                               &tdev->device);
        if (ret)
-               return ret;
+               goto powerdown;
+
+       *pdevice = &tdev->device;

        return 0;
+
+powerdown:
+       nvkm_device_tegra_power_down(tdev);
+remove:
+       nvkm_device_tegra_remove_iommu(tdev);
+free:
+       kfree(tdev);
+       return ret;
 }
 #else
 int
-- 
2.7.1