[PATCH] drm: tda998x: mali-dp: hdlcd: refactor connector registration

From: Brian Starkey
Date: Mon Oct 24 2016 - 10:28:20 EST


Connectors shouldn't be registered until the rest of the whole device
is set up, so that consistent state is presented to userspace.

As such, remove the calls to drm_connector_register() and
drm_connector_unregister() from tda998x, as these are now handled by
drm_dev_(un)register() itself.

To work with this change, the mali-dp and hdlcd bind and unbind
sequences have to be reordered, to ensure that the componentised
encoder/connector is bound before drm_dev_register() registers all
connectors. Similarly, the device must be unregistered before the
component is unbound.

Altogether, this allows other drivers using tda998x to be
de-midlayered, and to have less racy initialisation of their components.

Splitting this commit into three (one per driver) isn't possible without
intermediate breakage, so it is all squashed together here.

Suggested-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
Signed-off-by: Brian Starkey <brian.starkey@xxxxxxx>
Reviewed-by: Liviu Dudau <Liviu.Dudau@xxxxxxx>
---
drivers/gpu/drm/arm/hdlcd_drv.c | 19 +++++++++++--------
drivers/gpu/drm/arm/malidp_drv.c | 18 +++++++++++-------
drivers/gpu/drm/i2c/tda998x_drv.c | 8 --------
3 files changed, 22 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/arm/hdlcd_drv.c b/drivers/gpu/drm/arm/hdlcd_drv.c
index d83b46a..85aec8b 100644
--- a/drivers/gpu/drm/arm/hdlcd_drv.c
+++ b/drivers/gpu/drm/arm/hdlcd_drv.c
@@ -337,14 +337,10 @@ static int hdlcd_drm_bind(struct device *dev)
if (ret)
goto err_free;

- ret = drm_dev_register(drm, 0);
- if (ret)
- goto err_unload;
-
ret = component_bind_all(dev, drm);
if (ret) {
DRM_ERROR("Failed to bind all components\n");
- goto err_unregister;
+ goto err_unload;
}

ret = pm_runtime_set_active(dev);
@@ -371,8 +367,17 @@ static int hdlcd_drm_bind(struct device *dev)
goto err_fbdev;
}

+ ret = drm_dev_register(drm, 0);
+ if (ret)
+ goto err_register;
+
return 0;

+err_register:
+ if (hdlcd->fbdev) {
+ drm_fbdev_cma_fini(hdlcd->fbdev);
+ hdlcd->fbdev = NULL;
+ }
err_fbdev:
drm_kms_helper_poll_fini(drm);
drm_mode_config_cleanup(drm);
@@ -381,8 +386,6 @@ err_vblank:
pm_runtime_disable(drm->dev);
err_pm_active:
component_unbind_all(dev, drm);
-err_unregister:
- drm_dev_unregister(drm);
err_unload:
drm_irq_uninstall(drm);
of_reserved_mem_device_release(drm->dev);
@@ -398,6 +401,7 @@ static void hdlcd_drm_unbind(struct device *dev)
struct drm_device *drm = dev_get_drvdata(dev);
struct hdlcd_drm_private *hdlcd = drm->dev_private;

+ drm_dev_unregister(drm);
if (hdlcd->fbdev) {
drm_fbdev_cma_fini(hdlcd->fbdev);
hdlcd->fbdev = NULL;
@@ -411,7 +415,6 @@ static void hdlcd_drm_unbind(struct device *dev)
pm_runtime_disable(drm->dev);
of_reserved_mem_device_release(drm->dev);
drm_mode_config_cleanup(drm);
- drm_dev_unregister(drm);
drm_dev_unref(drm);
drm->dev_private = NULL;
dev_set_drvdata(dev, NULL);
diff --git a/drivers/gpu/drm/arm/malidp_drv.c b/drivers/gpu/drm/arm/malidp_drv.c
index 82171d2..79bfc13 100644
--- a/drivers/gpu/drm/arm/malidp_drv.c
+++ b/drivers/gpu/drm/arm/malidp_drv.c
@@ -354,10 +354,6 @@ static int malidp_bind(struct device *dev)
if (ret < 0)
goto init_fail;

- ret = drm_dev_register(drm, 0);
- if (ret)
- goto register_fail;
-
/* Set the CRTC's port so that the encoder component can find it */
ep = of_graph_get_next_endpoint(dev->of_node, NULL);
if (!ep) {
@@ -394,8 +390,18 @@ static int malidp_bind(struct device *dev)
}

drm_kms_helper_poll_init(drm);
+
+ ret = drm_dev_register(drm, 0);
+ if (ret)
+ goto register_fail;
+
return 0;

+register_fail:
+ if (malidp->fbdev) {
+ drm_fbdev_cma_fini(malidp->fbdev);
+ malidp->fbdev = NULL;
+ }
fbdev_fail:
drm_vblank_cleanup(drm);
vblank_fail:
@@ -407,8 +413,6 @@ bind_fail:
of_node_put(malidp->crtc.port);
malidp->crtc.port = NULL;
port_fail:
- drm_dev_unregister(drm);
-register_fail:
malidp_de_planes_destroy(drm);
drm_mode_config_cleanup(drm);
init_fail:
@@ -431,6 +435,7 @@ static void malidp_unbind(struct device *dev)
struct malidp_drm *malidp = drm->dev_private;
struct malidp_hw_device *hwdev = malidp->dev;

+ drm_dev_unregister(drm);
if (malidp->fbdev) {
drm_fbdev_cma_fini(malidp->fbdev);
malidp->fbdev = NULL;
@@ -442,7 +447,6 @@ static void malidp_unbind(struct device *dev)
component_unbind_all(dev, drm);
of_node_put(malidp->crtc.port);
malidp->crtc.port = NULL;
- drm_dev_unregister(drm);
malidp_de_planes_destroy(drm);
drm_mode_config_cleanup(drm);
drm->dev_private = NULL;
diff --git a/drivers/gpu/drm/i2c/tda998x_drv.c b/drivers/gpu/drm/i2c/tda998x_drv.c
index f4315bc..6e6fca2 100644
--- a/drivers/gpu/drm/i2c/tda998x_drv.c
+++ b/drivers/gpu/drm/i2c/tda998x_drv.c
@@ -1369,7 +1369,6 @@ const struct drm_connector_helper_funcs tda998x_connector_helper_funcs = {

static void tda998x_connector_destroy(struct drm_connector *connector)
{
- drm_connector_unregister(connector);
drm_connector_cleanup(connector);
}

@@ -1441,16 +1440,10 @@ static int tda998x_bind(struct device *dev, struct device *master, void *data)
if (ret)
goto err_connector;

- ret = drm_connector_register(&priv->connector);
- if (ret)
- goto err_sysfs;
-
drm_mode_connector_attach_encoder(&priv->connector, &priv->encoder);

return 0;

-err_sysfs:
- drm_connector_cleanup(&priv->connector);
err_connector:
drm_encoder_cleanup(&priv->encoder);
err_encoder:
@@ -1463,7 +1456,6 @@ static void tda998x_unbind(struct device *dev, struct device *master,
{
struct tda998x_priv *priv = dev_get_drvdata(dev);

- drm_connector_unregister(&priv->connector);
drm_connector_cleanup(&priv->connector);
drm_encoder_cleanup(&priv->encoder);
tda998x_destroy(priv);
--
1.7.9.5