drm/msm/a6xx: Fix up QMP handling

The commit referenced in the Fixes tag had a couple problems (as
pointed out by Dan):

- qmp_put was never called, resulting in refcnt leaks
- failling to acquire the QMP mailbox on A7xx would not undo the probe
  function properly
- the qmp_put call present in the code was unreachable

Fix all of these issues.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Fixes: 88a0997f2f94 ("drm/msm/a6xx: Send ACD state to QMP at GMU resume")
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/562761/
Signed-off-by: Rob Clark <robdclark@chromium.org>

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
index 0555a0134fada71fde2ce1172cf417d7f3b6b656..8c4900444b2c99ced029f4978ff5d1cbabaf6509 100644 (file)
--- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
@@ -1558,6 +1558,9 @@ void a6xx_gmu_remove(struct a6xx_gpu *a6xx_gpu)
                dev_pm_domain_detach(gmu->gxpd, false);
        }
 
+       if (!IS_ERR_OR_NULL(gmu->qmp))
+               qmp_put(gmu->qmp);
+
        iounmap(gmu->mmio);
        if (platform_get_resource_byname(pdev, IORESOURCE_MEM, "rscc"))
                iounmap(gmu->rscc);
@@ -1654,6 +1657,7 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
        struct adreno_gpu *adreno_gpu = &a6xx_gpu->base;
        struct a6xx_gmu *gmu = &a6xx_gpu->gmu;
        struct platform_device *pdev = of_find_device_by_node(node);
+       struct device_link *link;
        int ret;
 
        if (!pdev)
@@ -1777,15 +1781,17 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
                goto err_mmio;
        }
 
-       if (!device_link_add(gmu->dev, gmu->cxpd,
-                                       DL_FLAG_PM_RUNTIME)) {
+       link = device_link_add(gmu->dev, gmu->cxpd, DL_FLAG_PM_RUNTIME);
+       if (!link) {
                ret = -ENODEV;
                goto detach_cxpd;
        }
 
        gmu->qmp = qmp_get(gmu->dev);
-       if (IS_ERR(gmu->qmp) && adreno_is_a7xx(adreno_gpu))
-               return PTR_ERR(gmu->qmp);
+       if (IS_ERR(gmu->qmp) && adreno_is_a7xx(adreno_gpu)) {
+               ret = PTR_ERR(gmu->qmp);
+               goto remove_device_link;
+       }
 
        init_completion(&gmu->pd_gate);
        complete_all(&gmu->pd_gate);
@@ -1810,8 +1816,8 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
 
        return 0;
 
-       if (!IS_ERR_OR_NULL(gmu->qmp))
-               qmp_put(gmu->qmp);
+remove_device_link:
+       device_link_del(link);
 
 detach_cxpd:
        dev_pm_domain_detach(gmu->cxpd, false);