[PATCH net-next] net: stmmac: Handle different error codes from platform_get_irq_byname

[PATCH net-next] net: stmmac: Handle different error codes from platform_get_irq_byname

[Chen-Yu Tsai]

The following patch moved device tree interrupt resolution into
platform_get_irq_byname:

  ad69674 of/irq: do irq resolution in platform_get_irq_byname()

As a result, the function no longer only return -ENXIO on error.
This breaks DT based probing of stmmac, as seen in test runs of
linux-next next-20140526 cubie2-sunxi_defconfig:

  http://lists.linaro.org/pipermail/kernel-build-reports/2014-May/003659.html

This patch makes the stmmac_platform probe function properly handle
error codes, such as returning for deferred probing, and other codes
returned by of_irq_get_by_name.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 .../net/ethernet/stmicro/stmmac/stmmac_platform.c    | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
index 46aef510..9562b18 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
@@ -237,10 +237,12 @@ static int stmmac_pltfr_probe(struct platform_device *pdev)
 
 	/* Get the MAC information */
 	priv->dev->irq = platform_get_irq_byname(pdev, "macirq");
-	if (priv->dev->irq == -ENXIO) {
-		pr_err("%s: ERROR: MAC IRQ configuration "
-		       "information not found\n", __func__);
-		return -ENXIO;
+	if (priv->dev->irq < 0) {
+		if (priv->wol_irq != -EPROBE_DEFER) {
+			pr_err("%s: ERROR: MAC IRQ configuration "
+			       "information not found\n", __func__);
+		}
+		return priv->dev->irq;
 	}
 
 	/*
@@ -252,10 +254,18 @@ static int stmmac_pltfr_probe(struct platform_device *pdev)
 	 * so the driver will continue to use the mac irq (ndev->irq)
 	 */
 	priv->wol_irq = platform_get_irq_byname(pdev, "eth_wake_irq");
-	if (priv->wol_irq == -ENXIO)
+	if (priv->wol_irq < 0) {
+		if (priv->wol_irq == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
 		priv->wol_irq = priv->dev->irq;
+	}
 
 	priv->lpi_irq = platform_get_irq_byname(pdev, "eth_lpi");
+	if (priv->lpi_irq < 0) {
+		if (priv->wol_irq == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		priv->lpi_irq = -ENXIO;
+	}
 
 	platform_set_drvdata(pdev, priv->dev);
 
-- 
2.0.0.rc2

Re: [PATCH net-next] net: stmmac: Handle different error codes from platform_get_irq_byname

[Rob Herring]

On Mon, May 26, 2014 at 11:49 PM, Chen-Yu Tsai <wens@csie.org> wrote:
> The following patch moved device tree interrupt resolution into
> platform_get_irq_byname:
>
>   ad69674 of/irq: do irq resolution in platform_get_irq_byname()
>
> As a result, the function no longer only return -ENXIO on error.
> This breaks DT based probing of stmmac, as seen in test runs of
> linux-next next-20140526 cubie2-sunxi_defconfig:
>
>   http://lists.linaro.org/pipermail/kernel-build-reports/2014-May/003659.html
>
> This patch makes the stmmac_platform probe function properly handle
> error codes, such as returning for deferred probing, and other codes
> returned by of_irq_get_by_name.

ST u8500 is also broken as reported by Kevin Hilman.

>
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
> ---
>  .../net/ethernet/stmicro/stmmac/stmmac_platform.c    | 20 +++++++++++++++-----
>  1 file changed, 15 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
> index 46aef510..9562b18 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
> @@ -237,10 +237,12 @@ static int stmmac_pltfr_probe(struct platform_device *pdev)
>
>         /* Get the MAC information */
>         priv->dev->irq = platform_get_irq_byname(pdev, "macirq");
> -       if (priv->dev->irq == -ENXIO) {
> -               pr_err("%s: ERROR: MAC IRQ configuration "
> -                      "information not found\n", __func__);
> -               return -ENXIO;
> +       if (priv->dev->irq < 0) {
> +               if (priv->wol_irq != -EPROBE_DEFER) {

s/wol_irq/dev->irq/

> +                       pr_err("%s: ERROR: MAC IRQ configuration "

netdev_err

> +                              "information not found\n", __func__);

Don't split strings.

> +               }
> +               return priv->dev->irq;
>         }
>
>         /*
> @@ -252,10 +254,18 @@ static int stmmac_pltfr_probe(struct platform_device *pdev)
>          * so the driver will continue to use the mac irq (ndev->irq)
>          */
>         priv->wol_irq = platform_get_irq_byname(pdev, "eth_wake_irq");
> -       if (priv->wol_irq == -ENXIO)
> +       if (priv->wol_irq < 0) {
> +               if (priv->wol_irq == -EPROBE_DEFER)
> +                       return -EPROBE_DEFER;
>                 priv->wol_irq = priv->dev->irq;
> +       }
>
>         priv->lpi_irq = platform_get_irq_byname(pdev, "eth_lpi");
> +       if (priv->lpi_irq < 0) {

You don't need this if.

> +               if (priv->wol_irq == -EPROBE_DEFER)

s/wol_irq/lpi_irq/

> +                       return -EPROBE_DEFER;
> +               priv->lpi_irq = -ENXIO;
> +       }
>
>         platform_set_drvdata(pdev, priv->dev);
>
> --
> 2.0.0.rc2
>

Re: [PATCH net-next] net: stmmac: Handle different error codes from platform_get_irq_byname

[Chen-Yu Tsai]

On Wed, May 28, 2014 at 8:58 AM, Rob Herring <robh@kernel.org> wrote:
> On Mon, May 26, 2014 at 11:49 PM, Chen-Yu Tsai <wens@csie.org> wrote:
>> The following patch moved device tree interrupt resolution into
>> platform_get_irq_byname:
>>
>>   ad69674 of/irq: do irq resolution in platform_get_irq_byname()
>>
>> As a result, the function no longer only return -ENXIO on error.
>> This breaks DT based probing of stmmac, as seen in test runs of
>> linux-next next-20140526 cubie2-sunxi_defconfig:
>>
>>   http://lists.linaro.org/pipermail/kernel-build-reports/2014-May/003659.html
>>
>> This patch makes the stmmac_platform probe function properly handle
>> error codes, such as returning for deferred probing, and other codes
>> returned by of_irq_get_by_name.
>
> ST u8500 is also broken as reported by Kevin Hilman.

Saw the mail today.

>>
>> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
>> ---
>>  .../net/ethernet/stmicro/stmmac/stmmac_platform.c    | 20 +++++++++++++++-----
>>  1 file changed, 15 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
>> index 46aef510..9562b18 100644
>> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
>> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
>> @@ -237,10 +237,12 @@ static int stmmac_pltfr_probe(struct platform_device *pdev)
>>
>>         /* Get the MAC information */
>>         priv->dev->irq = platform_get_irq_byname(pdev, "macirq");
>> -       if (priv->dev->irq == -ENXIO) {
>> -               pr_err("%s: ERROR: MAC IRQ configuration "
>> -                      "information not found\n", __func__);
>> -               return -ENXIO;
>> +       if (priv->dev->irq < 0) {
>> +               if (priv->wol_irq != -EPROBE_DEFER) {
>
> s/wol_irq/dev->irq/

Copy paste error :(

>> +                       pr_err("%s: ERROR: MAC IRQ configuration "
>
> netdev_err
>
>> +                              "information not found\n", __func__);
>
> Don't split strings.

It was in the original code. Will fix.

>> +               }
>> +               return priv->dev->irq;
>>         }
>>
>>         /*
>> @@ -252,10 +254,18 @@ static int stmmac_pltfr_probe(struct platform_device *pdev)
>>          * so the driver will continue to use the mac irq (ndev->irq)
>>          */
>>         priv->wol_irq = platform_get_irq_byname(pdev, "eth_wake_irq");
>> -       if (priv->wol_irq == -ENXIO)
>> +       if (priv->wol_irq < 0) {
>> +               if (priv->wol_irq == -EPROBE_DEFER)
>> +                       return -EPROBE_DEFER;
>>                 priv->wol_irq = priv->dev->irq;
>> +       }
>>
>>         priv->lpi_irq = platform_get_irq_byname(pdev, "eth_lpi");
>> +       if (priv->lpi_irq < 0) {
>
> You don't need this if.

stmmac core driver checks lpi_irq != -ENXIO for valid interrupt.
Might as well change that check to  lpi_irq >= 0.
(0 is a valid interrupt, correct?)

Interestingly, stmmac_pci never sets lpi_irq, there might be a glitch
there.

>> +               if (priv->wol_irq == -EPROBE_DEFER)
>
> s/wol_irq/lpi_irq/

ditto

>> +                       return -EPROBE_DEFER;
>> +               priv->lpi_irq = -ENXIO;
>> +       }
>>
>>         platform_set_drvdata(pdev, priv->dev);
>>
>> --
>> 2.0.0.rc2
>>


Thanks
ChenYu

Re: [PATCH net-next] net: stmmac: Handle different error codes from platform_get_irq_byname

[Rob Herring]

On Wed, May 28, 2014 at 1:44 AM, Chen-Yu Tsai <wens@csie.org> wrote:
> On Wed, May 28, 2014 at 8:58 AM, Rob Herring <robh@kernel.org> wrote:
>> On Mon, May 26, 2014 at 11:49 PM, Chen-Yu Tsai <wens@csie.org> wrote:
>>> The following patch moved device tree interrupt resolution into
>>> platform_get_irq_byname:
>>>
>>>   ad69674 of/irq: do irq resolution in platform_get_irq_byname()
>>>
>>> As a result, the function no longer only return -ENXIO on error.
>>> This breaks DT based probing of stmmac, as seen in test runs of
>>> linux-next next-20140526 cubie2-sunxi_defconfig:

[...]

>>>         priv->lpi_irq = platform_get_irq_byname(pdev, "eth_lpi");
>>> +       if (priv->lpi_irq < 0) {
>>
>> You don't need this if.
>
> stmmac core driver checks lpi_irq != -ENXIO for valid interrupt.
> Might as well change that check to  lpi_irq >= 0.
> (0 is a valid interrupt, correct?)

No. NO_IRQ is defined to 0 (preferred) or -1 depending on the arch.
You should be testing for "> 0" for valid irq rather than only ENXIO.

My comment still stands. If lpi_irq is already <0, then there is no
reason to set it to -ENXIO (again). If there are other error codes
returned, changing the error code is not good practice.

> Interestingly, stmmac_pci never sets lpi_irq, there might be a glitch
> there.

I believe they would have to be combined to a single interrrupt for PCI.

Rob