drm/msm/dsi: Fix some reference counted resource leaks

[ Upstream commit 6977cc8 ]

'of_find_device_by_node()' takes a reference that must be released when
not needed anymore.
This is expected to be done in 'dsi_destroy()'.

However, there are 2 issues in 'dsi_get_phy()'.

First, if 'of_find_device_by_node()' succeeds but 'platform_get_drvdata()'
returns NULL, 'msm_dsi->phy_dev' will still be NULL, and the reference
won't be released in 'dsi_destroy()'.

Secondly, as 'of_find_device_by_node()' already takes a reference, there is
no need for an additional 'get_device()'.

Move the assignment to 'msm_dsi->phy_dev' a few lines above and remove the
unneeded 'get_device()' to solve both issues.

Fixes: ec31abf ("drm/msm/dsi: Separate PHY to another platform device")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/f15bc57648a00e7c99f943903468a04639d50596.1628241097.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/gpu/drm/msm/dsi/dsi.c

@@ -26,8 +26,10 @@ static int dsi_get_phy(struct msm_dsi *msm_dsi)
 	}
 
 	phy_pdev = of_find_device_by_node(phy_node);
-	if (phy_pdev)
+	if (phy_pdev) {
 		msm_dsi->phy = platform_get_drvdata(phy_pdev);
+		msm_dsi->phy_dev = &phy_pdev->dev;
+	}
 
 	of_node_put(phy_node);
 
@@ -36,8 +38,6 @@ static int dsi_get_phy(struct msm_dsi *msm_dsi)
 		return -EPROBE_DEFER;
 	}
 
-	msm_dsi->phy_dev = get_device(&phy_pdev->dev);
-
 	return 0;
 }