[RESEND,v2,2/2] drm/bridge: dw-hdmi: Always add the bridge in the global bridge list
diff mbox series

Message ID 1594260156-8316-2-git-send-email-victor.liu@nxp.com
State New
Headers show
Series
  • [RESEND,v2,1/2] drm/bridge: dw-hdmi: Don't cleanup i2c adapter and ddc ptr in __dw_hdmi_probe() bailout path
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Commit Message

Liu Ying July 9, 2020, 2:02 a.m. UTC
It doesn't hurt to add the bridge in the global bridge list also for
platform specific dw-hdmi drivers which are based on the component
framework.  This can be achieved by moving the drm_bridge_add() function
call from dw_hdmi_probe() to __dw_hdmi_probe().  A counterpart movement
for drm_bridge_remove() is also needed then.  Moreover, since drm_bridge_add()
initializes &bridge->hpd_mutex, this may help those platform specific
dw-hdmi drivers(based on the component framework) avoid accessing the
uninitialized mutex in drm_bridge_hpd_notify() which is called in
dw_hdmi_irq().  Putting drm_bridge_add() in __dw_hdmi_probe() just before
it returns successfully should bring no logic change for platforms based
on the DRM bridge API, which is a good choice from safety point of view.
Also, __dw_hdmi_probe() is renamed to dw_hdmi_probe() since dw_hdmi_probe()
does nothing else but calling __dw_hdmi_probe().  Similar renaming applies
to the __dw_hdmi_remove()/dw_hdmi_remove() pair.

Fixes: ec971aaa6775 ("drm: bridge: dw-hdmi: Make connector creation optional")
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Jonas Karlman <jonas@kwiboo.se>
Cc: Jernej Skrabec <jernej.skrabec@siol.net>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Cc: Cheng-Yi Chiang <cychiang@chromium.org>
Cc: Dariusz Marcinkiewicz <darekm@google.com>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Jose Abreu <joabreu@synopsys.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: dri-devel@lists.freedesktop.org
Cc: NXP Linux Team <linux-imx@nxp.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v1->v2:
* Put drm_bridge_add() in __dw_hdmi_probe() just before it returns
  successfully so that the bridge shows up in the global bridge list
  late enough to avoid potential race condition with other display
  drivers. (Laurent)
* Rename __dw_hdmi_probe/remove() to dw_hdmi_probe/remove()
  respectively. (Laurent)
* Cc'ed Sam.

 drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 44 +++++++++----------------------
 1 file changed, 13 insertions(+), 31 deletions(-)

Comments

Sam Ravnborg July 10, 2020, 5:32 p.m. UTC | #1
On Thu, Jul 09, 2020 at 10:02:36AM +0800, Liu Ying wrote:
> It doesn't hurt to add the bridge in the global bridge list also for
> platform specific dw-hdmi drivers which are based on the component
> framework.  This can be achieved by moving the drm_bridge_add() function
> call from dw_hdmi_probe() to __dw_hdmi_probe().  A counterpart movement
> for drm_bridge_remove() is also needed then.  Moreover, since drm_bridge_add()
> initializes &bridge->hpd_mutex, this may help those platform specific
> dw-hdmi drivers(based on the component framework) avoid accessing the
> uninitialized mutex in drm_bridge_hpd_notify() which is called in
> dw_hdmi_irq().  Putting drm_bridge_add() in __dw_hdmi_probe() just before
> it returns successfully should bring no logic change for platforms based
> on the DRM bridge API, which is a good choice from safety point of view.
> Also, __dw_hdmi_probe() is renamed to dw_hdmi_probe() since dw_hdmi_probe()
> does nothing else but calling __dw_hdmi_probe().  Similar renaming applies
> to the __dw_hdmi_remove()/dw_hdmi_remove() pair.

Hmm, it took me some attempts to read this.
Anyway, applied as-is to drm-misc-next.

	Sam

> 
> Fixes: ec971aaa6775 ("drm: bridge: dw-hdmi: Make connector creation optional")
> Cc: Andrzej Hajda <a.hajda@samsung.com>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> Cc: Jonas Karlman <jonas@kwiboo.se>
> Cc: Jernej Skrabec <jernej.skrabec@siol.net>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: Boris Brezillon <boris.brezillon@collabora.com>
> Cc: Jerome Brunet <jbrunet@baylibre.com>
> Cc: Cheng-Yi Chiang <cychiang@chromium.org>
> Cc: Dariusz Marcinkiewicz <darekm@google.com>
> Cc: Archit Taneja <architt@codeaurora.org>
> Cc: Jose Abreu <joabreu@synopsys.com>
> Cc: Sam Ravnborg <sam@ravnborg.org>
> Cc: dri-devel@lists.freedesktop.org
> Cc: NXP Linux Team <linux-imx@nxp.com>
> Signed-off-by: Liu Ying <victor.liu@nxp.com>
> ---
> v1->v2:
> * Put drm_bridge_add() in __dw_hdmi_probe() just before it returns
>   successfully so that the bridge shows up in the global bridge list
>   late enough to avoid potential race condition with other display
>   drivers. (Laurent)
> * Rename __dw_hdmi_probe/remove() to dw_hdmi_probe/remove()
>   respectively. (Laurent)
> * Cc'ed Sam.
> 
>  drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 44 +++++++++----------------------
>  1 file changed, 13 insertions(+), 31 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> index 137b6eb..748df1c 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> @@ -3179,9 +3179,11 @@ static void dw_hdmi_init_hw(struct dw_hdmi *hdmi)
>  		hdmi->phy.ops->setup_hpd(hdmi, hdmi->phy.data);
>  }
>  
> -static struct dw_hdmi *
> -__dw_hdmi_probe(struct platform_device *pdev,
> -		const struct dw_hdmi_plat_data *plat_data)
> +/* -----------------------------------------------------------------------------
> + * Probe/remove API, used from platforms based on the DRM bridge API.
> + */
> +struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
> +			      const struct dw_hdmi_plat_data *plat_data)
>  {
>  	struct device *dev = &pdev->dev;
>  	struct device_node *np = dev->of_node;
> @@ -3438,6 +3440,8 @@ __dw_hdmi_probe(struct platform_device *pdev,
>  		hdmi->cec = platform_device_register_full(&pdevinfo);
>  	}
>  
> +	drm_bridge_add(&hdmi->bridge);
> +
>  	return hdmi;
>  
>  err_iahb:
> @@ -3451,9 +3455,12 @@ __dw_hdmi_probe(struct platform_device *pdev,
>  
>  	return ERR_PTR(ret);
>  }
> +EXPORT_SYMBOL_GPL(dw_hdmi_probe);
>  
> -static void __dw_hdmi_remove(struct dw_hdmi *hdmi)
> +void dw_hdmi_remove(struct dw_hdmi *hdmi)
>  {
> +	drm_bridge_remove(&hdmi->bridge);
> +
>  	if (hdmi->audio && !IS_ERR(hdmi->audio))
>  		platform_device_unregister(hdmi->audio);
>  	if (!IS_ERR(hdmi->cec))
> @@ -3472,31 +3479,6 @@ static void __dw_hdmi_remove(struct dw_hdmi *hdmi)
>  	else
>  		i2c_put_adapter(hdmi->ddc);
>  }
> -
> -/* -----------------------------------------------------------------------------
> - * Probe/remove API, used from platforms based on the DRM bridge API.
> - */
> -struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
> -			      const struct dw_hdmi_plat_data *plat_data)
> -{
> -	struct dw_hdmi *hdmi;
> -
> -	hdmi = __dw_hdmi_probe(pdev, plat_data);
> -	if (IS_ERR(hdmi))
> -		return hdmi;
> -
> -	drm_bridge_add(&hdmi->bridge);
> -
> -	return hdmi;
> -}
> -EXPORT_SYMBOL_GPL(dw_hdmi_probe);
> -
> -void dw_hdmi_remove(struct dw_hdmi *hdmi)
> -{
> -	drm_bridge_remove(&hdmi->bridge);
> -
> -	__dw_hdmi_remove(hdmi);
> -}
>  EXPORT_SYMBOL_GPL(dw_hdmi_remove);
>  
>  /* -----------------------------------------------------------------------------
> @@ -3509,7 +3491,7 @@ struct dw_hdmi *dw_hdmi_bind(struct platform_device *pdev,
>  	struct dw_hdmi *hdmi;
>  	int ret;
>  
> -	hdmi = __dw_hdmi_probe(pdev, plat_data);
> +	hdmi = dw_hdmi_probe(pdev, plat_data);
>  	if (IS_ERR(hdmi))
>  		return hdmi;
>  
> @@ -3526,7 +3508,7 @@ EXPORT_SYMBOL_GPL(dw_hdmi_bind);
>  
>  void dw_hdmi_unbind(struct dw_hdmi *hdmi)
>  {
> -	__dw_hdmi_remove(hdmi);
> +	dw_hdmi_remove(hdmi);
>  }
>  EXPORT_SYMBOL_GPL(dw_hdmi_unbind);
>  
> -- 
> 2.7.4
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
Liu Ying July 11, 2020, 12:59 a.m. UTC | #2
On Fri, 2020-07-10 at 19:32 +0200, Sam Ravnborg wrote:
> On Thu, Jul 09, 2020 at 10:02:36AM +0800, Liu Ying wrote:
> > It doesn't hurt to add the bridge in the global bridge list also
> > for
> > platform specific dw-hdmi drivers which are based on the component
> > framework.  This can be achieved by moving the drm_bridge_add()
> > function
> > call from dw_hdmi_probe() to __dw_hdmi_probe().  A counterpart
> > movement
> > for drm_bridge_remove() is also needed then.  Moreover, since
> > drm_bridge_add()
> > initializes &bridge->hpd_mutex, this may help those platform
> > specific
> > dw-hdmi drivers(based on the component framework) avoid accessing
> > the
> > uninitialized mutex in drm_bridge_hpd_notify() which is called in
> > dw_hdmi_irq().  Putting drm_bridge_add() in __dw_hdmi_probe() just
> > before
> > it returns successfully should bring no logic change for platforms
> > based
> > on the DRM bridge API, which is a good choice from safety point of
> > view.
> > Also, __dw_hdmi_probe() is renamed to dw_hdmi_probe() since
> > dw_hdmi_probe()
> > does nothing else but calling __dw_hdmi_probe().  Similar renaming
> > applies
> > to the __dw_hdmi_remove()/dw_hdmi_remove() pair.
> 
> Hmm, it took me some attempts to read this.
> Anyway, applied as-is to drm-misc-next.

Thank you, Sam.

Liu Ying

> 
> 	Sam
> 
> > 
> > Fixes: ec971aaa6775 ("drm: bridge: dw-hdmi: Make connector creation
> > optional")
> > Cc: Andrzej Hajda <a.hajda@samsung.com>
> > Cc: Neil Armstrong <narmstrong@baylibre.com>
> > Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> > Cc: Jonas Karlman <jonas@kwiboo.se>
> > Cc: Jernej Skrabec <jernej.skrabec@siol.net>
> > Cc: David Airlie <airlied@linux.ie>
> > Cc: Daniel Vetter <daniel@ffwll.ch>
> > Cc: Boris Brezillon <boris.brezillon@collabora.com>
> > Cc: Jerome Brunet <jbrunet@baylibre.com>
> > Cc: Cheng-Yi Chiang <cychiang@chromium.org>
> > Cc: Dariusz Marcinkiewicz <darekm@google.com>
> > Cc: Archit Taneja <architt@codeaurora.org>
> > Cc: Jose Abreu <joabreu@synopsys.com>
> > Cc: Sam Ravnborg <sam@ravnborg.org>
> > Cc: dri-devel@lists.freedesktop.org
> > Cc: NXP Linux Team <linux-imx@nxp.com>
> > Signed-off-by: Liu Ying <victor.liu@nxp.com>
> > ---
> > v1->v2:
> > * Put drm_bridge_add() in __dw_hdmi_probe() just before it returns
> >   successfully so that the bridge shows up in the global bridge
> > list
> >   late enough to avoid potential race condition with other display
> >   drivers. (Laurent)
> > * Rename __dw_hdmi_probe/remove() to dw_hdmi_probe/remove()
> >   respectively. (Laurent)
> > * Cc'ed Sam.
> > 
> >  drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 44 +++++++++--------
> > --------------
> >  1 file changed, 13 insertions(+), 31 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > index 137b6eb..748df1c 100644
> > --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > @@ -3179,9 +3179,11 @@ static void dw_hdmi_init_hw(struct dw_hdmi
> > *hdmi)
> >  		hdmi->phy.ops->setup_hpd(hdmi, hdmi->phy.data);
> >  }
> >  
> > -static struct dw_hdmi *
> > -__dw_hdmi_probe(struct platform_device *pdev,
> > -		const struct dw_hdmi_plat_data *plat_data)
> > +/* -------------------------------------------------------------
> > ----------------
> > + * Probe/remove API, used from platforms based on the DRM bridge
> > API.
> > + */
> > +struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
> > +			      const struct dw_hdmi_plat_data
> > *plat_data)
> >  {
> >  	struct device *dev = &pdev->dev;
> >  	struct device_node *np = dev->of_node;
> > @@ -3438,6 +3440,8 @@ __dw_hdmi_probe(struct platform_device *pdev,
> >  		hdmi->cec = platform_device_register_full(&pdevinfo);
> >  	}
> >  
> > +	drm_bridge_add(&hdmi->bridge);
> > +
> >  	return hdmi;
> >  
> >  err_iahb:
> > @@ -3451,9 +3455,12 @@ __dw_hdmi_probe(struct platform_device
> > *pdev,
> >  
> >  	return ERR_PTR(ret);
> >  }
> > +EXPORT_SYMBOL_GPL(dw_hdmi_probe);
> >  
> > -static void __dw_hdmi_remove(struct dw_hdmi *hdmi)
> > +void dw_hdmi_remove(struct dw_hdmi *hdmi)
> >  {
> > +	drm_bridge_remove(&hdmi->bridge);
> > +
> >  	if (hdmi->audio && !IS_ERR(hdmi->audio))
> >  		platform_device_unregister(hdmi->audio);
> >  	if (!IS_ERR(hdmi->cec))
> > @@ -3472,31 +3479,6 @@ static void __dw_hdmi_remove(struct dw_hdmi
> > *hdmi)
> >  	else
> >  		i2c_put_adapter(hdmi->ddc);
> >  }
> > -
> > -/* -------------------------------------------------------------
> > ----------------
> > - * Probe/remove API, used from platforms based on the DRM bridge
> > API.
> > - */
> > -struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
> > -			      const struct dw_hdmi_plat_data
> > *plat_data)
> > -{
> > -	struct dw_hdmi *hdmi;
> > -
> > -	hdmi = __dw_hdmi_probe(pdev, plat_data);
> > -	if (IS_ERR(hdmi))
> > -		return hdmi;
> > -
> > -	drm_bridge_add(&hdmi->bridge);
> > -
> > -	return hdmi;
> > -}
> > -EXPORT_SYMBOL_GPL(dw_hdmi_probe);
> > -
> > -void dw_hdmi_remove(struct dw_hdmi *hdmi)
> > -{
> > -	drm_bridge_remove(&hdmi->bridge);
> > -
> > -	__dw_hdmi_remove(hdmi);
> > -}
> >  EXPORT_SYMBOL_GPL(dw_hdmi_remove);
> >  
> >  /* -------------------------------------------------------------
> > ----------------
> > @@ -3509,7 +3491,7 @@ struct dw_hdmi *dw_hdmi_bind(struct
> > platform_device *pdev,
> >  	struct dw_hdmi *hdmi;
> >  	int ret;
> >  
> > -	hdmi = __dw_hdmi_probe(pdev, plat_data);
> > +	hdmi = dw_hdmi_probe(pdev, plat_data);
> >  	if (IS_ERR(hdmi))
> >  		return hdmi;
> >  
> > @@ -3526,7 +3508,7 @@ EXPORT_SYMBOL_GPL(dw_hdmi_bind);
> >  
> >  void dw_hdmi_unbind(struct dw_hdmi *hdmi)
> >  {
> > -	__dw_hdmi_remove(hdmi);
> > +	dw_hdmi_remove(hdmi);
> >  }
> >  EXPORT_SYMBOL_GPL(dw_hdmi_unbind);
> >  
> > -- 
> > 2.7.4
> > 
> > _______________________________________________
> > dri-devel mailing list
> > dri-devel@lists.freedesktop.org
> > 
https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Fdri-devel&amp;data=02%7C01%7Cvictor.liu%40nxp.com%7C0f923c54af014f54175608d824f72c5d%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637299991302447959&amp;sdata=kgoboL8o%2Ft0qvvlQw4nyrHlcusib5Ynuc%2BY%2Fn70fu14%3D&amp;reserved=0

Patch
diff mbox series

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index 137b6eb..748df1c 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -3179,9 +3179,11 @@  static void dw_hdmi_init_hw(struct dw_hdmi *hdmi)
 		hdmi->phy.ops->setup_hpd(hdmi, hdmi->phy.data);
 }
 
-static struct dw_hdmi *
-__dw_hdmi_probe(struct platform_device *pdev,
-		const struct dw_hdmi_plat_data *plat_data)
+/* -----------------------------------------------------------------------------
+ * Probe/remove API, used from platforms based on the DRM bridge API.
+ */
+struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
+			      const struct dw_hdmi_plat_data *plat_data)
 {
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev->of_node;
@@ -3438,6 +3440,8 @@  __dw_hdmi_probe(struct platform_device *pdev,
 		hdmi->cec = platform_device_register_full(&pdevinfo);
 	}
 
+	drm_bridge_add(&hdmi->bridge);
+
 	return hdmi;
 
 err_iahb:
@@ -3451,9 +3455,12 @@  __dw_hdmi_probe(struct platform_device *pdev,
 
 	return ERR_PTR(ret);
 }
+EXPORT_SYMBOL_GPL(dw_hdmi_probe);
 
-static void __dw_hdmi_remove(struct dw_hdmi *hdmi)
+void dw_hdmi_remove(struct dw_hdmi *hdmi)
 {
+	drm_bridge_remove(&hdmi->bridge);
+
 	if (hdmi->audio && !IS_ERR(hdmi->audio))
 		platform_device_unregister(hdmi->audio);
 	if (!IS_ERR(hdmi->cec))
@@ -3472,31 +3479,6 @@  static void __dw_hdmi_remove(struct dw_hdmi *hdmi)
 	else
 		i2c_put_adapter(hdmi->ddc);
 }
-
-/* -----------------------------------------------------------------------------
- * Probe/remove API, used from platforms based on the DRM bridge API.
- */
-struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
-			      const struct dw_hdmi_plat_data *plat_data)
-{
-	struct dw_hdmi *hdmi;
-
-	hdmi = __dw_hdmi_probe(pdev, plat_data);
-	if (IS_ERR(hdmi))
-		return hdmi;
-
-	drm_bridge_add(&hdmi->bridge);
-
-	return hdmi;
-}
-EXPORT_SYMBOL_GPL(dw_hdmi_probe);
-
-void dw_hdmi_remove(struct dw_hdmi *hdmi)
-{
-	drm_bridge_remove(&hdmi->bridge);
-
-	__dw_hdmi_remove(hdmi);
-}
 EXPORT_SYMBOL_GPL(dw_hdmi_remove);
 
 /* -----------------------------------------------------------------------------
@@ -3509,7 +3491,7 @@  struct dw_hdmi *dw_hdmi_bind(struct platform_device *pdev,
 	struct dw_hdmi *hdmi;
 	int ret;
 
-	hdmi = __dw_hdmi_probe(pdev, plat_data);
+	hdmi = dw_hdmi_probe(pdev, plat_data);
 	if (IS_ERR(hdmi))
 		return hdmi;
 
@@ -3526,7 +3508,7 @@  EXPORT_SYMBOL_GPL(dw_hdmi_bind);
 
 void dw_hdmi_unbind(struct dw_hdmi *hdmi)
 {
-	__dw_hdmi_remove(hdmi);
+	dw_hdmi_remove(hdmi);
 }
 EXPORT_SYMBOL_GPL(dw_hdmi_unbind);