diff mbox series

[3/3] drm/msm/dsi: make sure we have panel or bridge earlier

Message ID 20190630131445.25712-4-robdclark@gmail.com (mailing list archive)
State Not Applicable, archived
Headers show
Series drm/msm: few small cleanups | expand

Commit Message

Rob Clark June 30, 2019, 1:14 p.m. UTC
From: Rob Clark <robdclark@chromium.org>

If we are going to -EPROBE_DEFER due to panel/bridge not probed yet, we
want to do it before we start touching hardware.

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
 drivers/gpu/drm/msm/dsi/dsi.h         |  2 +-
 drivers/gpu/drm/msm/dsi/dsi_host.c    | 30 +++++++++++++--------------
 drivers/gpu/drm/msm/dsi/dsi_manager.c |  9 +++-----
 3 files changed, 19 insertions(+), 22 deletions(-)

Comments

Jeffrey Hugo July 2, 2019, 8:30 p.m. UTC | #1
On Sun, Jun 30, 2019 at 7:16 AM Rob Clark <robdclark@gmail.com> wrote:
> --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> @@ -1824,6 +1824,20 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
>                 goto fail;
>         }
>
> +       /*
> +        * Make sure we have panel or bridge early, before we start
> +        * touching the hw.  If bootloader enabled the display, we
> +        * want to be sure to keep it running until the bridge/panel
> +        * is probed and we are all ready to go.  Otherwise we'll
> +        * kill the display and then -EPROBE_DEFER
> +        */
> +       if (IS_ERR(of_drm_find_panel(msm_host->device_node)) &&
> +                       !of_drm_find_bridge(msm_host->device_node)) {
> +               pr_err("%s: no panel or bridge yet\n", __func__);

pr_err() doesn't seem right for a probe defer condition.  pr_dbg?

> +               return -EPROBE_DEFER;
> +       }
> +
> +

Tested-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Reviewed-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Jeffrey Hugo July 2, 2019, 9:29 p.m. UTC | #2
On Tue, Jul 2, 2019 at 2:30 PM Jeffrey Hugo <jeffrey.l.hugo@gmail.com> wrote:
>
> On Sun, Jun 30, 2019 at 7:16 AM Rob Clark <robdclark@gmail.com> wrote:
> > --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> > +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> > @@ -1824,6 +1824,20 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
> >                 goto fail;
> >         }
> >
> > +       /*
> > +        * Make sure we have panel or bridge early, before we start
> > +        * touching the hw.  If bootloader enabled the display, we
> > +        * want to be sure to keep it running until the bridge/panel
> > +        * is probed and we are all ready to go.  Otherwise we'll
> > +        * kill the display and then -EPROBE_DEFER
> > +        */
> > +       if (IS_ERR(of_drm_find_panel(msm_host->device_node)) &&
> > +                       !of_drm_find_bridge(msm_host->device_node)) {
> > +               pr_err("%s: no panel or bridge yet\n", __func__);
>
> pr_err() doesn't seem right for a probe defer condition.  pr_dbg?
>
> > +               return -EPROBE_DEFER;
> > +       }
> > +
> > +
>
> Tested-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
> Reviewed-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>

Actually, I'm sorry, I'm now NACKing this.

Turns out this prevents the panel/bridge from ever probing if its a
child node of the dsi device, since mipi_dsi_host_register() is never
called.

This probably works for you on the c630 because the bridge hangs off
the i2c bus.
Andrzej Hajda July 4, 2019, 6:39 a.m. UTC | #3
On 30.06.2019 15:14, Rob Clark wrote:
> From: Rob Clark <robdclark@chromium.org>
>
> If we are going to -EPROBE_DEFER due to panel/bridge not probed yet, we
> want to do it before we start touching hardware.


As the evidence shows, if the driver create bus (mipi-dsi), then it
should not defer probing due to lack of sink (panel/bridge), because the
sink will not appear without the bus.

Instead of defer probing you can defer component binding, or if you like
challenges you can implement dynamic sink binding :)


Regards

Andrzej




>
> Signed-off-by: Rob Clark <robdclark@chromium.org>
> ---
>  drivers/gpu/drm/msm/dsi/dsi.h         |  2 +-
>  drivers/gpu/drm/msm/dsi/dsi_host.c    | 30 +++++++++++++--------------
>  drivers/gpu/drm/msm/dsi/dsi_manager.c |  9 +++-----
>  3 files changed, 19 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dsi/dsi.h b/drivers/gpu/drm/msm/dsi/dsi.h
> index 53bb124e8259..e15e7534ccd9 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi.h
> +++ b/drivers/gpu/drm/msm/dsi/dsi.h
> @@ -171,7 +171,7 @@ int msm_dsi_host_set_display_mode(struct mipi_dsi_host *host,
>  struct drm_panel *msm_dsi_host_get_panel(struct mipi_dsi_host *host);
>  unsigned long msm_dsi_host_get_mode_flags(struct mipi_dsi_host *host);
>  struct drm_bridge *msm_dsi_host_get_bridge(struct mipi_dsi_host *host);
> -int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer);
> +int msm_dsi_host_register(struct mipi_dsi_host *host);
>  void msm_dsi_host_unregister(struct mipi_dsi_host *host);
>  int msm_dsi_host_set_src_pll(struct mipi_dsi_host *host,
>  			struct msm_dsi_pll *src_pll);
> diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
> index 1ae2f5522979..8e5b0ba9431e 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> @@ -1824,6 +1824,20 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
>  		goto fail;
>  	}
>  
> +	/*
> +	 * Make sure we have panel or bridge early, before we start
> +	 * touching the hw.  If bootloader enabled the display, we
> +	 * want to be sure to keep it running until the bridge/panel
> +	 * is probed and we are all ready to go.  Otherwise we'll
> +	 * kill the display and then -EPROBE_DEFER
> +	 */
> +	if (IS_ERR(of_drm_find_panel(msm_host->device_node)) &&
> +			!of_drm_find_bridge(msm_host->device_node)) {
> +		pr_err("%s: no panel or bridge yet\n", __func__);
> +		return -EPROBE_DEFER;
> +	}
> +
> +
>  	msm_host->ctrl_base = msm_ioremap(pdev, "dsi_ctrl", "DSI CTRL");
>  	if (IS_ERR(msm_host->ctrl_base)) {
>  		pr_err("%s: unable to map Dsi ctrl base\n", __func__);
> @@ -1941,7 +1955,7 @@ int msm_dsi_host_modeset_init(struct mipi_dsi_host *host,
>  	return 0;
>  }
>  
> -int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer)
> +int msm_dsi_host_register(struct mipi_dsi_host *host)
>  {
>  	struct msm_dsi_host *msm_host = to_msm_dsi_host(host);
>  	int ret;
> @@ -1955,20 +1969,6 @@ int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer)
>  			return ret;
>  
>  		msm_host->registered = true;
> -
> -		/* If the panel driver has not been probed after host register,
> -		 * we should defer the host's probe.
> -		 * It makes sure panel is connected when fbcon detects
> -		 * connector status and gets the proper display mode to
> -		 * create framebuffer.
> -		 * Don't try to defer if there is nothing connected to the dsi
> -		 * output
> -		 */
> -		if (check_defer && msm_host->device_node) {
> -			if (IS_ERR(of_drm_find_panel(msm_host->device_node)))
> -				if (!of_drm_find_bridge(msm_host->device_node))
> -					return -EPROBE_DEFER;
> -		}
>  	}
>  
>  	return 0;
> diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/dsi/dsi_manager.c
> index ff39ce6150ad..cd3450dc3481 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
> @@ -82,7 +82,7 @@ static int dsi_mgr_setup_components(int id)
>  	int ret;
>  
>  	if (!IS_DUAL_DSI()) {
> -		ret = msm_dsi_host_register(msm_dsi->host, true);
> +		ret = msm_dsi_host_register(msm_dsi->host);
>  		if (ret)
>  			return ret;
>  
> @@ -101,14 +101,11 @@ static int dsi_mgr_setup_components(int id)
>  		/* Register slave host first, so that slave DSI device
>  		 * has a chance to probe, and do not block the master
>  		 * DSI device's probe.
> -		 * Also, do not check defer for the slave host,
> -		 * because only master DSI device adds the panel to global
> -		 * panel list. The panel's device is the master DSI device.
>  		 */
> -		ret = msm_dsi_host_register(slave_link_dsi->host, false);
> +		ret = msm_dsi_host_register(slave_link_dsi->host);
>  		if (ret)
>  			return ret;
> -		ret = msm_dsi_host_register(master_link_dsi->host, true);
> +		ret = msm_dsi_host_register(master_link_dsi->host);
>  		if (ret)
>  			return ret;
>
Rob Clark July 4, 2019, 2 p.m. UTC | #4
On Wed, Jul 3, 2019 at 11:39 PM Andrzej Hajda <a.hajda@samsung.com> wrote:
>
> On 30.06.2019 15:14, Rob Clark wrote:
> > From: Rob Clark <robdclark@chromium.org>
> >
> > If we are going to -EPROBE_DEFER due to panel/bridge not probed yet, we
> > want to do it before we start touching hardware.
>
>
> As the evidence shows, if the driver create bus (mipi-dsi), then it
> should not defer probing due to lack of sink (panel/bridge), because the
> sink will not appear without the bus.
>
> Instead of defer probing you can defer component binding, or if you like
> challenges you can implement dynamic sink binding :)
>

I have something working that doesn't require this patch.. although it
does require CCF to export a function to check if clks are enabled so
the driver can detect if the display is already enabled.  (Well, there
kind of is, __clk_is_enabled().. but currently in clk-provider.h)

So we can drop this patch.

BR,
-R

>
> Regards
>
> Andrzej
>
>
>
>
> >
> > Signed-off-by: Rob Clark <robdclark@chromium.org>
> > ---
> >  drivers/gpu/drm/msm/dsi/dsi.h         |  2 +-
> >  drivers/gpu/drm/msm/dsi/dsi_host.c    | 30 +++++++++++++--------------
> >  drivers/gpu/drm/msm/dsi/dsi_manager.c |  9 +++-----
> >  3 files changed, 19 insertions(+), 22 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/msm/dsi/dsi.h b/drivers/gpu/drm/msm/dsi/dsi.h
> > index 53bb124e8259..e15e7534ccd9 100644
> > --- a/drivers/gpu/drm/msm/dsi/dsi.h
> > +++ b/drivers/gpu/drm/msm/dsi/dsi.h
> > @@ -171,7 +171,7 @@ int msm_dsi_host_set_display_mode(struct mipi_dsi_host *host,
> >  struct drm_panel *msm_dsi_host_get_panel(struct mipi_dsi_host *host);
> >  unsigned long msm_dsi_host_get_mode_flags(struct mipi_dsi_host *host);
> >  struct drm_bridge *msm_dsi_host_get_bridge(struct mipi_dsi_host *host);
> > -int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer);
> > +int msm_dsi_host_register(struct mipi_dsi_host *host);
> >  void msm_dsi_host_unregister(struct mipi_dsi_host *host);
> >  int msm_dsi_host_set_src_pll(struct mipi_dsi_host *host,
> >                       struct msm_dsi_pll *src_pll);
> > diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
> > index 1ae2f5522979..8e5b0ba9431e 100644
> > --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> > +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> > @@ -1824,6 +1824,20 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
> >               goto fail;
> >       }
> >
> > +     /*
> > +      * Make sure we have panel or bridge early, before we start
> > +      * touching the hw.  If bootloader enabled the display, we
> > +      * want to be sure to keep it running until the bridge/panel
> > +      * is probed and we are all ready to go.  Otherwise we'll
> > +      * kill the display and then -EPROBE_DEFER
> > +      */
> > +     if (IS_ERR(of_drm_find_panel(msm_host->device_node)) &&
> > +                     !of_drm_find_bridge(msm_host->device_node)) {
> > +             pr_err("%s: no panel or bridge yet\n", __func__);
> > +             return -EPROBE_DEFER;
> > +     }
> > +
> > +
> >       msm_host->ctrl_base = msm_ioremap(pdev, "dsi_ctrl", "DSI CTRL");
> >       if (IS_ERR(msm_host->ctrl_base)) {
> >               pr_err("%s: unable to map Dsi ctrl base\n", __func__);
> > @@ -1941,7 +1955,7 @@ int msm_dsi_host_modeset_init(struct mipi_dsi_host *host,
> >       return 0;
> >  }
> >
> > -int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer)
> > +int msm_dsi_host_register(struct mipi_dsi_host *host)
> >  {
> >       struct msm_dsi_host *msm_host = to_msm_dsi_host(host);
> >       int ret;
> > @@ -1955,20 +1969,6 @@ int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer)
> >                       return ret;
> >
> >               msm_host->registered = true;
> > -
> > -             /* If the panel driver has not been probed after host register,
> > -              * we should defer the host's probe.
> > -              * It makes sure panel is connected when fbcon detects
> > -              * connector status and gets the proper display mode to
> > -              * create framebuffer.
> > -              * Don't try to defer if there is nothing connected to the dsi
> > -              * output
> > -              */
> > -             if (check_defer && msm_host->device_node) {
> > -                     if (IS_ERR(of_drm_find_panel(msm_host->device_node)))
> > -                             if (!of_drm_find_bridge(msm_host->device_node))
> > -                                     return -EPROBE_DEFER;
> > -             }
> >       }
> >
> >       return 0;
> > diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/dsi/dsi_manager.c
> > index ff39ce6150ad..cd3450dc3481 100644
> > --- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
> > +++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
> > @@ -82,7 +82,7 @@ static int dsi_mgr_setup_components(int id)
> >       int ret;
> >
> >       if (!IS_DUAL_DSI()) {
> > -             ret = msm_dsi_host_register(msm_dsi->host, true);
> > +             ret = msm_dsi_host_register(msm_dsi->host);
> >               if (ret)
> >                       return ret;
> >
> > @@ -101,14 +101,11 @@ static int dsi_mgr_setup_components(int id)
> >               /* Register slave host first, so that slave DSI device
> >                * has a chance to probe, and do not block the master
> >                * DSI device's probe.
> > -              * Also, do not check defer for the slave host,
> > -              * because only master DSI device adds the panel to global
> > -              * panel list. The panel's device is the master DSI device.
> >                */
> > -             ret = msm_dsi_host_register(slave_link_dsi->host, false);
> > +             ret = msm_dsi_host_register(slave_link_dsi->host);
> >               if (ret)
> >                       return ret;
> > -             ret = msm_dsi_host_register(master_link_dsi->host, true);
> > +             ret = msm_dsi_host_register(master_link_dsi->host);
> >               if (ret)
> >                       return ret;
> >
>
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/msm/dsi/dsi.h b/drivers/gpu/drm/msm/dsi/dsi.h
index 53bb124e8259..e15e7534ccd9 100644
--- a/drivers/gpu/drm/msm/dsi/dsi.h
+++ b/drivers/gpu/drm/msm/dsi/dsi.h
@@ -171,7 +171,7 @@  int msm_dsi_host_set_display_mode(struct mipi_dsi_host *host,
 struct drm_panel *msm_dsi_host_get_panel(struct mipi_dsi_host *host);
 unsigned long msm_dsi_host_get_mode_flags(struct mipi_dsi_host *host);
 struct drm_bridge *msm_dsi_host_get_bridge(struct mipi_dsi_host *host);
-int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer);
+int msm_dsi_host_register(struct mipi_dsi_host *host);
 void msm_dsi_host_unregister(struct mipi_dsi_host *host);
 int msm_dsi_host_set_src_pll(struct mipi_dsi_host *host,
 			struct msm_dsi_pll *src_pll);
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 1ae2f5522979..8e5b0ba9431e 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -1824,6 +1824,20 @@  int msm_dsi_host_init(struct msm_dsi *msm_dsi)
 		goto fail;
 	}
 
+	/*
+	 * Make sure we have panel or bridge early, before we start
+	 * touching the hw.  If bootloader enabled the display, we
+	 * want to be sure to keep it running until the bridge/panel
+	 * is probed and we are all ready to go.  Otherwise we'll
+	 * kill the display and then -EPROBE_DEFER
+	 */
+	if (IS_ERR(of_drm_find_panel(msm_host->device_node)) &&
+			!of_drm_find_bridge(msm_host->device_node)) {
+		pr_err("%s: no panel or bridge yet\n", __func__);
+		return -EPROBE_DEFER;
+	}
+
+
 	msm_host->ctrl_base = msm_ioremap(pdev, "dsi_ctrl", "DSI CTRL");
 	if (IS_ERR(msm_host->ctrl_base)) {
 		pr_err("%s: unable to map Dsi ctrl base\n", __func__);
@@ -1941,7 +1955,7 @@  int msm_dsi_host_modeset_init(struct mipi_dsi_host *host,
 	return 0;
 }
 
-int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer)
+int msm_dsi_host_register(struct mipi_dsi_host *host)
 {
 	struct msm_dsi_host *msm_host = to_msm_dsi_host(host);
 	int ret;
@@ -1955,20 +1969,6 @@  int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer)
 			return ret;
 
 		msm_host->registered = true;
-
-		/* If the panel driver has not been probed after host register,
-		 * we should defer the host's probe.
-		 * It makes sure panel is connected when fbcon detects
-		 * connector status and gets the proper display mode to
-		 * create framebuffer.
-		 * Don't try to defer if there is nothing connected to the dsi
-		 * output
-		 */
-		if (check_defer && msm_host->device_node) {
-			if (IS_ERR(of_drm_find_panel(msm_host->device_node)))
-				if (!of_drm_find_bridge(msm_host->device_node))
-					return -EPROBE_DEFER;
-		}
 	}
 
 	return 0;
diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/dsi/dsi_manager.c
index ff39ce6150ad..cd3450dc3481 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
@@ -82,7 +82,7 @@  static int dsi_mgr_setup_components(int id)
 	int ret;
 
 	if (!IS_DUAL_DSI()) {
-		ret = msm_dsi_host_register(msm_dsi->host, true);
+		ret = msm_dsi_host_register(msm_dsi->host);
 		if (ret)
 			return ret;
 
@@ -101,14 +101,11 @@  static int dsi_mgr_setup_components(int id)
 		/* Register slave host first, so that slave DSI device
 		 * has a chance to probe, and do not block the master
 		 * DSI device's probe.
-		 * Also, do not check defer for the slave host,
-		 * because only master DSI device adds the panel to global
-		 * panel list. The panel's device is the master DSI device.
 		 */
-		ret = msm_dsi_host_register(slave_link_dsi->host, false);
+		ret = msm_dsi_host_register(slave_link_dsi->host);
 		if (ret)
 			return ret;
-		ret = msm_dsi_host_register(master_link_dsi->host, true);
+		ret = msm_dsi_host_register(master_link_dsi->host);
 		if (ret)
 			return ret;