drm/msm: Upgrade gxpd checks to IS_ERR_OR_NULL

dev_pm_domain_attach_by_name() can return NULL, so we should check for
that case when we're about to dereference gxpd.

Fixes: 9325d4266afd ("drm/msm/gpu: Attach to the GPU GX power domain")
Cc: Jordan Crouse <jcrouse@codeaurora.org>
Cc: Rob Clark <robdclark@chromium.org>
Reviewed-by: Jordan Crouse <jcrouse@codeauorora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190515170104.155525-1-sean@poorly.run

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
index 9155daf..38e2cfa 100644 (file)
--- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
@@ -747,7 +747,7 @@ int a6xx_gmu_resume(struct a6xx_gpu *a6xx_gpu)
         * will make sure that the refcounting is correct in case we need to
         * bring down the GX after a GMU failure
         */
-       if (!IS_ERR(gmu->gxpd))
+       if (!IS_ERR_OR_NULL(gmu->gxpd))
                pm_runtime_get(gmu->gxpd);
 
 out:
@@ -863,7 +863,7 @@ int a6xx_gmu_stop(struct a6xx_gpu *a6xx_gpu)
         * domain. Usually the GMU does this but only if the shutdown sequence
         * was successful
         */
-       if (!IS_ERR(gmu->gxpd))
+       if (!IS_ERR_OR_NULL(gmu->gxpd))
                pm_runtime_put_sync(gmu->gxpd);
 
        clk_bulk_disable_unprepare(gmu->nr_clocks, gmu->clocks);
@@ -1234,7 +1234,7 @@ void a6xx_gmu_remove(struct a6xx_gpu *a6xx_gpu)
 
        pm_runtime_disable(gmu->dev);
 
-       if (!IS_ERR(gmu->gxpd)) {
+       if (!IS_ERR_OR_NULL(gmu->gxpd)) {
                pm_runtime_disable(gmu->gxpd);
                dev_pm_domain_detach(gmu->gxpd, false);
        }