[PATCH v2] rtc: s3c: Don't print an error on probe deferral

[PATCH v2] rtc: s3c: Don't print an error on probe deferral

[Javier Martinez Canillas]

The clock and source clock looked up by the driver may not be available
just because the clock controller driver was not probed yet so printing
an error in this case is not correct and only adds confusion to users.

However, knowing that a driver's probe was deferred may be useful so it
can be printed as debug information.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>

---

Changes in v2:
- Improve debug messages as suggested by Joe Perches.

 drivers/rtc/rtc-s3c.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
index ffb860d18701..4a3a8eb35234 100644
--- a/drivers/rtc/rtc-s3c.c
+++ b/drivers/rtc/rtc-s3c.c
@@ -501,18 +501,27 @@ static int s3c_rtc_probe(struct platform_device *pdev)
 
 	info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
 	if (IS_ERR(info->rtc_clk)) {
-		dev_err(&pdev->dev, "failed to find rtc clock\n");
-		return PTR_ERR(info->rtc_clk);
+		ret = PTR_ERR(info->rtc_clk);
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "failed to find rtc clock\n");
+		else
+			dev_dbg(&pdev->dev, "probe deferred due missing rtc clk\n");
+		return ret;
 	}
 	clk_prepare_enable(info->rtc_clk);
 
 	if (info->data->needs_src_clk) {
 		info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
 		if (IS_ERR(info->rtc_src_clk)) {
-			dev_err(&pdev->dev,
-				"failed to find rtc source clock\n");
+			ret = PTR_ERR(info->rtc_src_clk);
+			if (ret != -EPROBE_DEFER)
+				dev_err(&pdev->dev,
+					"failed to find rtc source clock\n");
+			else
+				dev_dbg(&pdev->dev,
+					"probe deferred due missing rtc src clk\n");
 			clk_disable_unprepare(info->rtc_clk);
-			return PTR_ERR(info->rtc_src_clk);
+			return ret;
 		}
 		clk_prepare_enable(info->rtc_src_clk);
 	}
-- 
2.5.0

Re: [PATCH v2] rtc: s3c: Don't print an error on probe deferral

[Joe Perches]

On Mon, 2016-03-14 at 17:25 -0300, Javier Martinez Canillas wrote:
> The clock and source clock looked up by the driver may not be available
> just because the clock controller driver was not probed yet so printing
> an error in this case is not correct and only adds confusion to users.
> 
> However, knowing that a driver's probe was deferred may be useful so it
> can be printed as debug information.

Hello again Javier:
> +			dev_dbg(&pdev->dev, "probe deferred due missing rtc clk\n");

Again, intelligible English would not use "due"
but would use "due to" or "because of".

> +				dev_dbg(&pdev->dev,
> +					"probe deferred due missing rtc src clk\n");

here too.

Re: [PATCH v2] rtc: s3c: Don't print an error on probe deferral

[Javier Martinez Canillas]

Hello Joe,

On 03/14/2016 05:30 PM, Joe Perches wrote:
> On Mon, 2016-03-14 at 17:25 -0300, Javier Martinez Canillas wrote:
>> The clock and source clock looked up by the driver may not be available
>> just because the clock controller driver was not probed yet so printing
>> an error in this case is not correct and only adds confusion to users.
>>
>> However, knowing that a driver's probe was deferred may be useful so it
>> can be printed as debug information.
> 
> Hello again Javier:
>> +			dev_dbg(&pdev->dev, "probe deferred due missing rtc clk\n");
> 
> Again, intelligible English would not use "due"
> but would use "due to" or "because of".
> 

Ok, I'll post another version then. I hope the third time's the charm...

Alexandre, do you have any other comments before I re-spin this patch?

Best regards,
-- 
Javier Martinez Canillas
Open Source Group
Samsung Research America

Re: [PATCH v2] rtc: s3c: Don't print an error on probe deferral

[Alexandre Belloni]

On 14/03/2016 at 18:07:36 -0300, Javier Martinez Canillas wrote :
> Hello Joe,
> 
> On 03/14/2016 05:30 PM, Joe Perches wrote:
> > On Mon, 2016-03-14 at 17:25 -0300, Javier Martinez Canillas wrote:
> >> The clock and source clock looked up by the driver may not be available
> >> just because the clock controller driver was not probed yet so printing
> >> an error in this case is not correct and only adds confusion to users.
> >>
> >> However, knowing that a driver's probe was deferred may be useful so it
> >> can be printed as debug information.
> > 
> > Hello again Javier:
> >> +			dev_dbg(&pdev->dev, "probe deferred due missing rtc clk\n");
> > 
> > Again, intelligible English would not use "due"
> > but would use "due to" or "because of".
> > 
> 
> Ok, I'll post another version then. I hope the third time's the charm...
> 
> Alexandre, do you have any other comments before I re-spin this patch?
> 

No further comments :)


-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com