[v2,9/9] drm/panel: truly-nt35597: Don't log an error when DSI host can't be found

Message ID 20240229-anx7625-defer-log-no-dsi-host-v2-9-00506941049a@collabora.com
State New
Headers
Series drm: Switch from dev_err to dev_err_probe for missing DSI host error path |

Commit Message

Nícolas F. R. A. Prado March 1, 2024, 12:12 a.m. UTC
  Given that failing to find a DSI host causes the driver to defer probe,
make use of dev_err_probe() to log the reason. This makes the defer
probe reason available and avoids alerting userspace about something
that is not necessarily an error.

Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
---
 drivers/gpu/drm/panel/panel-truly-nt35597.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)
  

Comments

Abhinav Kumar March 1, 2024, 12:31 a.m. UTC | #1
On 2/29/2024 4:12 PM, Nícolas F. R. A. Prado wrote:
> Given that failing to find a DSI host causes the driver to defer probe,
> make use of dev_err_probe() to log the reason. This makes the defer
> probe reason available and avoids alerting userspace about something
> that is not necessarily an error.
> 
> Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
> ---
>   drivers/gpu/drm/panel/panel-truly-nt35597.c | 6 ++----
>   1 file changed, 2 insertions(+), 4 deletions(-)
> 

Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
  
Laurent Pinchart March 1, 2024, 6:30 a.m. UTC | #2
Hi Nícolas,

Thank you for the patch.

On Thu, Feb 29, 2024 at 07:12:15PM -0500, Nícolas F. R. A. Prado wrote:
> Given that failing to find a DSI host causes the driver to defer probe,
> make use of dev_err_probe() to log the reason. This makes the defer
> probe reason available and avoids alerting userspace about something
> that is not necessarily an error.
> 
> Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
> ---
>  drivers/gpu/drm/panel/panel-truly-nt35597.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c
> index b73448cf349d..d447db912a61 100644
> --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c
> +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c
> @@ -550,10 +550,8 @@ static int truly_nt35597_probe(struct mipi_dsi_device *dsi)
>  
>  	dsi1_host = of_find_mipi_dsi_host_by_node(dsi1);
>  	of_node_put(dsi1);
> -	if (!dsi1_host) {
> -		dev_err(dev, "failed to find dsi host\n");
> -		return -EPROBE_DEFER;
> -	}
> +	if (!dsi1_host)
> +		return dev_err_probe(dev, -EPROBE_DEFER, "failed to find dsi host\n");

		return dev_err_probe(dev, -EPROBE_DEFER,
				     "failed to find dsi host\n");

With this addressed,

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

>  
>  	/* register the second DSI device */
>  	dsi1_device = mipi_dsi_device_register_full(dsi1_host, &info);
>
  
AngeloGioacchino Del Regno March 1, 2024, 8:44 a.m. UTC | #3
Il 01/03/24 07:30, Laurent Pinchart ha scritto:
> Hi Nícolas,
> 
> Thank you for the patch.
> 
> On Thu, Feb 29, 2024 at 07:12:15PM -0500, Nícolas F. R. A. Prado wrote:
>> Given that failing to find a DSI host causes the driver to defer probe,
>> make use of dev_err_probe() to log the reason. This makes the defer
>> probe reason available and avoids alerting userspace about something
>> that is not necessarily an error.
>>
>> Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
>> ---
>>   drivers/gpu/drm/panel/panel-truly-nt35597.c | 6 ++----
>>   1 file changed, 2 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c
>> index b73448cf349d..d447db912a61 100644
>> --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c
>> +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c
>> @@ -550,10 +550,8 @@ static int truly_nt35597_probe(struct mipi_dsi_device *dsi)
>>   
>>   	dsi1_host = of_find_mipi_dsi_host_by_node(dsi1);
>>   	of_node_put(dsi1);
>> -	if (!dsi1_host) {
>> -		dev_err(dev, "failed to find dsi host\n");
>> -		return -EPROBE_DEFER;
>> -	}
>> +	if (!dsi1_host)
>> +		return dev_err_probe(dev, -EPROBE_DEFER, "failed to find dsi host\n");
> 
> 		return dev_err_probe(dev, -EPROBE_DEFER,
> 				     "failed to find dsi host\n");
> 
> With this addressed,

I disagree. That's 87 columns, and the 80-col rule is long gone.

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> 
>>   
>>   	/* register the second DSI device */
>>   	dsi1_device = mipi_dsi_device_register_full(dsi1_host, &info);
>>
>
  
Laurent Pinchart March 1, 2024, 8:56 a.m. UTC | #4
On Fri, Mar 01, 2024 at 09:44:36AM +0100, AngeloGioacchino Del Regno wrote:
> Il 01/03/24 07:30, Laurent Pinchart ha scritto:
> > On Thu, Feb 29, 2024 at 07:12:15PM -0500, Nícolas F. R. A. Prado wrote:
> >> Given that failing to find a DSI host causes the driver to defer probe,
> >> make use of dev_err_probe() to log the reason. This makes the defer
> >> probe reason available and avoids alerting userspace about something
> >> that is not necessarily an error.
> >>
> >> Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> >> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
> >> ---
> >>   drivers/gpu/drm/panel/panel-truly-nt35597.c | 6 ++----
> >>   1 file changed, 2 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c
> >> index b73448cf349d..d447db912a61 100644
> >> --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c
> >> +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c
> >> @@ -550,10 +550,8 @@ static int truly_nt35597_probe(struct mipi_dsi_device *dsi)
> >>   
> >>   	dsi1_host = of_find_mipi_dsi_host_by_node(dsi1);
> >>   	of_node_put(dsi1);
> >> -	if (!dsi1_host) {
> >> -		dev_err(dev, "failed to find dsi host\n");
> >> -		return -EPROBE_DEFER;
> >> -	}
> >> +	if (!dsi1_host)
> >> +		return dev_err_probe(dev, -EPROBE_DEFER, "failed to find dsi host\n");
> > 
> > 		return dev_err_probe(dev, -EPROBE_DEFER,
> > 				     "failed to find dsi host\n");
> > 
> > With this addressed,
> 
> I disagree. That's 87 columns, and the 80-col rule is long gone.

It's still a maintainer's preference. I soft-enforce it in drivers I
maintain. In this case I'll let Neil decide, as he's listed as the
maintainer for drivers/gpu/drm/panel/.

> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> 
> > Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > 
> >>   
> >>   	/* register the second DSI device */
> >>   	dsi1_device = mipi_dsi_device_register_full(dsi1_host, &info);
  
AngeloGioacchino Del Regno March 1, 2024, 9:37 a.m. UTC | #5
Il 01/03/24 09:56, Laurent Pinchart ha scritto:
> On Fri, Mar 01, 2024 at 09:44:36AM +0100, AngeloGioacchino Del Regno wrote:
>> Il 01/03/24 07:30, Laurent Pinchart ha scritto:
>>> On Thu, Feb 29, 2024 at 07:12:15PM -0500, Nícolas F. R. A. Prado wrote:
>>>> Given that failing to find a DSI host causes the driver to defer probe,
>>>> make use of dev_err_probe() to log the reason. This makes the defer
>>>> probe reason available and avoids alerting userspace about something
>>>> that is not necessarily an error.
>>>>
>>>> Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>>>> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
>>>> ---
>>>>    drivers/gpu/drm/panel/panel-truly-nt35597.c | 6 ++----
>>>>    1 file changed, 2 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c
>>>> index b73448cf349d..d447db912a61 100644
>>>> --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c
>>>> +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c
>>>> @@ -550,10 +550,8 @@ static int truly_nt35597_probe(struct mipi_dsi_device *dsi)
>>>>    
>>>>    	dsi1_host = of_find_mipi_dsi_host_by_node(dsi1);
>>>>    	of_node_put(dsi1);
>>>> -	if (!dsi1_host) {
>>>> -		dev_err(dev, "failed to find dsi host\n");
>>>> -		return -EPROBE_DEFER;
>>>> -	}
>>>> +	if (!dsi1_host)
>>>> +		return dev_err_probe(dev, -EPROBE_DEFER, "failed to find dsi host\n");
>>>
>>> 		return dev_err_probe(dev, -EPROBE_DEFER,
>>> 				     "failed to find dsi host\n");
>>>
>>> With this addressed,
>>
>> I disagree. That's 87 columns, and the 80-col rule is long gone.
> 
> It's still a maintainer's preference. I soft-enforce it in drivers I
> maintain. In this case I'll let Neil decide, as he's listed as the
> maintainer for drivers/gpu/drm/panel/.
> 

Yes, that's right. Comes down to personal opinion.

Cheers

>> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>>
>>> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
>>>
>>>>    
>>>>    	/* register the second DSI device */
>>>>    	dsi1_device = mipi_dsi_device_register_full(dsi1_host, &info);
>
  
Neil Armstrong March 1, 2024, 10:54 a.m. UTC | #6
On 01/03/2024 10:37, AngeloGioacchino Del Regno wrote:
> Il 01/03/24 09:56, Laurent Pinchart ha scritto:
>> On Fri, Mar 01, 2024 at 09:44:36AM +0100, AngeloGioacchino Del Regno wrote:
>>> Il 01/03/24 07:30, Laurent Pinchart ha scritto:
>>>> On Thu, Feb 29, 2024 at 07:12:15PM -0500, Nícolas F. R. A. Prado wrote:
>>>>> Given that failing to find a DSI host causes the driver to defer probe,
>>>>> make use of dev_err_probe() to log the reason. This makes the defer
>>>>> probe reason available and avoids alerting userspace about something
>>>>> that is not necessarily an error.
>>>>>
>>>>> Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>>>>> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
>>>>> ---
>>>>>    drivers/gpu/drm/panel/panel-truly-nt35597.c | 6 ++----
>>>>>    1 file changed, 2 insertions(+), 4 deletions(-)
>>>>>
>>>>> diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c
>>>>> index b73448cf349d..d447db912a61 100644
>>>>> --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c
>>>>> +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c
>>>>> @@ -550,10 +550,8 @@ static int truly_nt35597_probe(struct mipi_dsi_device *dsi)
>>>>>        dsi1_host = of_find_mipi_dsi_host_by_node(dsi1);
>>>>>        of_node_put(dsi1);
>>>>> -    if (!dsi1_host) {
>>>>> -        dev_err(dev, "failed to find dsi host\n");
>>>>> -        return -EPROBE_DEFER;
>>>>> -    }
>>>>> +    if (!dsi1_host)
>>>>> +        return dev_err_probe(dev, -EPROBE_DEFER, "failed to find dsi host\n");
>>>>
>>>>         return dev_err_probe(dev, -EPROBE_DEFER,
>>>>                      "failed to find dsi host\n");
>>>>
>>>> With this addressed,
>>>
>>> I disagree. That's 87 columns, and the 80-col rule is long gone.
>>
>> It's still a maintainer's preference. I soft-enforce it in drivers I
>> maintain. In this case I'll let Neil decide, as he's listed as the
>> maintainer for drivers/gpu/drm/panel/.
>>
> 
> Yes, that's right. Comes down to personal opinion.

There always was an exception for strings to go over the 80col, and I like it better as an one-liner.
So I'm in favor with the initial proposal.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>


Neil

> 
> Cheers
> 
>>> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>>>
>>>> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
>>>>
>>>>>        /* register the second DSI device */
>>>>>        dsi1_device = mipi_dsi_device_register_full(dsi1_host, &info);
>>
>
  

Patch

diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c
index b73448cf349d..d447db912a61 100644
--- a/drivers/gpu/drm/panel/panel-truly-nt35597.c
+++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c
@@ -550,10 +550,8 @@  static int truly_nt35597_probe(struct mipi_dsi_device *dsi)
 
 	dsi1_host = of_find_mipi_dsi_host_by_node(dsi1);
 	of_node_put(dsi1);
-	if (!dsi1_host) {
-		dev_err(dev, "failed to find dsi host\n");
-		return -EPROBE_DEFER;
-	}
+	if (!dsi1_host)
+		return dev_err_probe(dev, -EPROBE_DEFER, "failed to find dsi host\n");
 
 	/* register the second DSI device */
 	dsi1_device = mipi_dsi_device_register_full(dsi1_host, &info);