[PATCH v5 29/36] drm/rockchip: analogix_dp: Do not call Analogix code before bind

[Enric Balletbo i Serra]

From: Tomasz Figa <tf...@chromium.org>

Driver callbacks, such as system suspend or resume can be called any
time, specifically they can be called before the component bind
callback. Let's use dp->adp pointer as a safeguard and skip calling
Analogix entry points if it is an ERR_PTR().

Signed-off-by: Tomasz Figa <tf...@chromium.org>
Signed-off-by: Thierry Escande <thierry.esca...@collabora.com>
Signed-off-by: Enric Balletbo i Serra <enric.balle...@collabora.com>
Tested-by: Marek Szyprowski <m.szyprow...@samsung.com>
---

 drivers/gpu/drm/rockchip/analogix_dp-rockchip.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c 
b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
index 23317a2269e1..6d45d62466b3 100644
--- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
+++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
@@ -368,6 +368,8 @@ static void rockchip_dp_unbind(struct device *dev, struct 
device *master,
        analogix_dp_unbind(dp->adp);
        rockchip_drm_psr_unregister(&dp->encoder);
        dp->encoder.funcs->destroy(&dp->encoder);
+
+       dp->adp = ERR_PTR(-ENODEV);
 }
 
 static const struct component_ops rockchip_dp_component_ops = {
@@ -391,6 +393,7 @@ static int rockchip_dp_probe(struct platform_device *pdev)
                return -ENOMEM;
 
        dp->dev = dev;
+       dp->adp = ERR_PTR(-ENODEV);
        dp->plat_data.panel = panel;
 
        ret = rockchip_dp_of_probe(dp);
@@ -414,6 +417,9 @@ static int rockchip_dp_suspend(struct device *dev)
 {
        struct rockchip_dp_device *dp = dev_get_drvdata(dev);
 
+       if (IS_ERR(dp->adp))
+               return 0;
+
        return analogix_dp_suspend(dp->adp);
 }
 
@@ -421,6 +427,9 @@ static int rockchip_dp_resume(struct device *dev)
 {
        struct rockchip_dp_device *dp = dev_get_drvdata(dev);
 
+       if (IS_ERR(dp->adp))
+               return 0;
+
        return analogix_dp_resume(dp->adp);
 }
 #endif
-- 
2.16.1