[PATCH v4 3/3] drm/msm: handle for EPROBE_DEFER for of_icc_get

[Jonathan Marek <jonathan@marek.ca>]

Check for errors instead of silently not using icc if the msm driver
probes before the interconnect driver.

Allow ENODATA for ocmem path, as it is optional and this error
is returned when "gfx-mem" path is provided but not "ocmem".

Because msm_gpu_cleanup assumes msm_gpu_init has been called, the icc path
init needs to be after msm_gpu_init for the error path to work.

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
---
 drivers/gpu/drm/msm/adreno/adreno_gpu.c | 65 +++++++++++++++----------
 1 file changed, 38 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index ad64d4b7e8d7..3f1ecc1de965 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -895,7 +895,7 @@ static int adreno_get_legacy_pwrlevels(struct device *dev)
 	return 0;
 }
 
-static int adreno_get_pwrlevels(struct device *dev,
+static void adreno_get_pwrlevels(struct device *dev,
 		struct msm_gpu *gpu)
 {
 	unsigned long freq = ULONG_MAX;
@@ -930,24 +930,6 @@ static int adreno_get_pwrlevels(struct device *dev,
 	}
 
 	DBG("fast_rate=%u, slow_rate=27000000", gpu->fast_rate);
-
-	/* Check for an interconnect path for the bus */
-	gpu->icc_path = of_icc_get(dev, "gfx-mem");
-	if (!gpu->icc_path) {
-		/*
-		 * Keep compatbility with device trees that don't have an
-		 * interconnect-names property.
-		 */
-		gpu->icc_path = of_icc_get(dev, NULL);
-	}
-	if (IS_ERR(gpu->icc_path))
-		gpu->icc_path = NULL;
-
-	gpu->ocmem_icc_path = of_icc_get(dev, "ocmem");
-	if (IS_ERR(gpu->ocmem_icc_path))
-		gpu->ocmem_icc_path = NULL;
-
-	return 0;
 }
 
 int adreno_gpu_ocmem_init(struct device *dev, struct adreno_gpu *adreno_gpu,
@@ -993,9 +975,11 @@ int adreno_gpu_init(struct drm_device *drm, struct platform_device *pdev,
 		struct adreno_gpu *adreno_gpu,
 		const struct adreno_gpu_funcs *funcs, int nr_rings)
 {
-	struct adreno_platform_config *config = pdev->dev.platform_data;
+	struct device *dev = &pdev->dev;
+	struct adreno_platform_config *config = dev->platform_data;
 	struct msm_gpu_config adreno_gpu_config  = { 0 };
 	struct msm_gpu *gpu = &adreno_gpu->base;
+	int ret;
 
 	adreno_gpu->funcs = funcs;
 	adreno_gpu->info = adreno_info(config->rev);
@@ -1007,15 +991,42 @@ int adreno_gpu_init(struct drm_device *drm, struct platform_device *pdev,
 
 	adreno_gpu_config.nr_rings = nr_rings;
 
-	adreno_get_pwrlevels(&pdev->dev, gpu);
+	adreno_get_pwrlevels(dev, gpu);
 
-	pm_runtime_set_autosuspend_delay(&pdev->dev,
+	pm_runtime_set_autosuspend_delay(dev,
 		adreno_gpu->info->inactive_period);
-	pm_runtime_use_autosuspend(&pdev->dev);
-	pm_runtime_enable(&pdev->dev);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_enable(dev);
 
-	return msm_gpu_init(drm, pdev, &adreno_gpu->base, &funcs->base,
+	ret = msm_gpu_init(drm, pdev, &adreno_gpu->base, &funcs->base,
 			adreno_gpu->info->name, &adreno_gpu_config);
+	if (ret)
+		return ret;
+
+	/* Check for an interconnect path for the bus */
+	gpu->icc_path = of_icc_get(dev, "gfx-mem");
+	if (!gpu->icc_path) {
+		/*
+		 * Keep compatbility with device trees that don't have an
+		 * interconnect-names property.
+		 */
+		gpu->icc_path = of_icc_get(dev, NULL);
+	}
+	if (IS_ERR(gpu->icc_path)) {
+		ret = PTR_ERR(gpu->icc_path);
+		gpu->icc_path = NULL;
+		return ret;
+	}
+
+	gpu->ocmem_icc_path = of_icc_get(dev, "ocmem");
+	if (IS_ERR(gpu->ocmem_icc_path)) {
+		ret = PTR_ERR(gpu->ocmem_icc_path);
+		gpu->ocmem_icc_path = NULL;
+		/* allow -ENODATA, ocmem icc is optional */
+		if (ret != -ENODATA)
+			return ret;
+	}
+	return 0;
 }
 
 void adreno_gpu_cleanup(struct adreno_gpu *adreno_gpu)
@@ -1029,8 +1040,8 @@ void adreno_gpu_cleanup(struct adreno_gpu *adreno_gpu)
 
 	pm_runtime_disable(&priv->gpu_pdev->dev);
 
+	msm_gpu_cleanup(&adreno_gpu->base);
+
 	icc_put(gpu->icc_path);
 	icc_put(gpu->ocmem_icc_path);
-
-	msm_gpu_cleanup(&adreno_gpu->base);
 }
-- 
2.26.1