[PATCH review for 4.9 21/50] drm/fsl-dcu: check for clk_prepare_enable() error

From: Levin, Alexander (Sasha Levin)
Date: Sat Oct 07 2017 - 18:48:33 EST


From: Fabio Estevam <fabio.estevam@xxxxxxx>

[ Upstream commit ef15d36154cc741d7ded4ae4fa0cf7987354e313 ]

clk_prepare_enable() may fail, so we should better check its return
value.

Also place the of_node_put() function right after clk_prepare_enable(),
in order to avoid calling of_node_put() twice in case clk_prepare_enable()
fails.

Signed-off-by: Fabio Estevam <fabio.estevam@xxxxxxx>
Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
drivers/gpu/drm/fsl-dcu/fsl_tcon.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_tcon.c b/drivers/gpu/drm/fsl-dcu/fsl_tcon.c
index 3194e544ee27..faacc813254c 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_tcon.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_tcon.c
@@ -89,9 +89,13 @@ struct fsl_tcon *fsl_tcon_init(struct device *dev)
goto err_node_put;
}

- of_node_put(np);
- clk_prepare_enable(tcon->ipg_clk);
+ ret = clk_prepare_enable(tcon->ipg_clk);
+ if (ret) {
+ dev_err(dev, "Couldn't enable the TCON clock\n");
+ goto err_node_put;
+ }

+ of_node_put(np);
dev_info(dev, "Using TCON in bypass mode\n");

return tcon;
--
2.11.0