[PATCH 05/14] drm/tegra: Inherit device DMA parameters from host1x

[Thierry Reding]

From: Thierry Reding <treding at nvidia.com>

The display controllers and VIC don't have any limitations on the
DMA segment size. Inherit the DMA parameters from the parent device,
which also doesn't have any such limitations.

Signed-off-by: Thierry Reding <treding at nvidia.com>
---
 drivers/gpu/drm/tegra/dc.c  | 9 +++++++++
 drivers/gpu/drm/tegra/vic.c | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index fbf57bc3cdab..f7f7984bb749 100644
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -2074,6 +2074,12 @@ static int tegra_dc_init(struct host1x_client *client)
 		goto cleanup;
 	}
 
+	/*
+	 * Inherit the DMA parameters (such as maximum segment size) from the
+	 * parent device.
+	 */
+	client->dev->dma_parms = client->parent->dma_parms;
+
 	return 0;
 
 cleanup:
@@ -2097,6 +2103,9 @@ static int tegra_dc_exit(struct host1x_client *client)
 	if (!tegra_dc_has_window_groups(dc))
 		return 0;
 
+	/* avoid a dangling pointer just in case this disappears */
+	client->dev->dma_parms = NULL;
+
 	devm_free_irq(dc->dev, dc->irq, dc);
 
 	err = tegra_dc_rgb_exit(dc);
diff --git a/drivers/gpu/drm/tegra/vic.c b/drivers/gpu/drm/tegra/vic.c
index c97a61c877af..8d98b0cfc47b 100644
--- a/drivers/gpu/drm/tegra/vic.c
+++ b/drivers/gpu/drm/tegra/vic.c
@@ -214,6 +214,12 @@ static int vic_init(struct host1x_client *client)
 	if (err < 0)
 		goto free_syncpt;
 
+	/*
+	 * Inherit the DMA parameters (such as maximum segment size) from the
+	 * parent device.
+	 */
+	client->dev->dma_parms = client->parent->dma_parms;
+
 	return 0;
 
 free_syncpt:
@@ -236,6 +242,9 @@ static int vic_exit(struct host1x_client *client)
 	struct vic *vic = to_vic(drm);
 	int err;
 
+	/* avoid a dangling pointer just in case this disappears */
+	client->dev->dma_parms = NULL;
+
 	err = tegra_drm_unregister_client(tegra, drm);
 	if (err < 0)
 		return err;
-- 
2.23.0