[PATCH] mwifiex: propagate error if IRQ request fails in mwifiex_sdio_of()

If request_irq() fails in mwifiex_sdio_probe_of(), only an error message
is printed but the actual error is not propagated to the caller function.

Signed-off-by: Javier Martinez Canillas <redacted>
---

 drivers/net/wireless/marvell/mwifiex/sdio.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/marvell/mwifiex/sdio.c b/drivers/net/wireless/marvell/mwifiex/sdio.c
index d3e1561ca075..00727936ad6e 100644
--- a/drivers/net/wireless/marvell/mwifiex/sdio.c
+++ b/drivers/net/wireless/marvell/mwifiex/sdio.c

@@ -125,6 +125,7 @@ static int mwifiex_sdio_probe_of(struct device *dev, struct sdio_mmc_card *card)
 				dev_err(dev,
 					"Failed to request irq_wifi %d (%d)\n",
 					cfg->irq_wifi, ret);
+				return ret;
 			}
 			disable_irq(cfg->irq_wifi);
 		}

-- 
2.5.5

On 18-08-16 21:29, Javier Martinez Canillas wrote:

Hello Arend,

Thanks a lot for your feedback.

On 08/18/2016 03:14 PM, Arend van Spriel wrote:

quoted

On 18-08-16 16:17, Javier Martinez Canillas wrote:

quoted

If request_irq() fails in mwifiex_sdio_probe_of(), only an error message
is printed but the actual error is not propagated to the caller function.

Hmm. The caller function, ie. mwifiex_sdio_probe(), does not seem to care.

Hmm, I'm not so sure about that. It's checking the wifiex_sdio_probe_of()
return value.

Ok. I looked at 4.7 sources on lxr [1].

If the IRQ request failing is not an error, then at the very least the call
to disable_irq() should be avoided if request_irq() fails, and the message
should be changed from dev_err() to dev_dgb() or dev_info().

agree.

quoted

The device may still function without this wake interrupt.

That's correct, the binding says that the "interrupts" property in the child
node is optional since is just a wakeup IRQ. Now the question is if should
be an error if the IRQ is defined but fails to be requested.

Clearly it indicates an error in the DT specification so behavior is not
as expected. Personally I would indeed consider it an error, but I was
just indicating that it might have done like this intentionally.

Regards,
Arend

[1]
http://lxr.free-electrons.com/source/drivers/net/wireless/marvell/mwifiex/sdio.c#L192

quoted

Regards,
Arend

Best regards,

On 18-08-16 16:17, Javier Martinez Canillas wrote:

If request_irq() fails in mwifiex_sdio_probe_of(), only an error message
is printed but the actual error is not propagated to the caller function.

Hmm. The caller function, ie. mwifiex_sdio_probe(), does not seem to care.

The device may still function without this wake interrupt.

Regards,
Arend

Hello Arend,

Thanks a lot for your feedback.

On 08/18/2016 03:14 PM, Arend van Spriel wrote:

On 18-08-16 16:17, Javier Martinez Canillas wrote:

quoted

If request_irq() fails in mwifiex_sdio_probe_of(), only an error message
is printed but the actual error is not propagated to the caller function.

Hmm. The caller function, ie. mwifiex_sdio_probe(), does not seem to care.

Hmm, I'm not so sure about that. It's checking the wifiex_sdio_probe_of()
return value.

If the IRQ request failing is not an error, then at the very least the call
to disable_irq() should be avoided if request_irq() fails, and the message
should be changed from dev_err() to dev_dgb() or dev_info().
 

The device may still function without this wake interrupt.

That's correct, the binding says that the "interrupts" property in the child
node is optional since is just a wakeup IRQ. Now the question is if should
be an error if the IRQ is defined but fails to be requested.

Regards,
Arend

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

Hello Arend,

On 08/18/2016 03:49 PM, Arend van Spriel wrote:

On 18-08-16 21:29, Javier Martinez Canillas wrote:

quoted

Hello Arend,

Thanks a lot for your feedback.

On 08/18/2016 03:14 PM, Arend van Spriel wrote:

quoted

On 18-08-16 16:17, Javier Martinez Canillas wrote:

quoted

If request_irq() fails in mwifiex_sdio_probe_of(), only an error message
is printed but the actual error is not propagated to the caller function.

Hmm. The caller function, ie. mwifiex_sdio_probe(), does not seem to care.

Hmm, I'm not so sure about that. It's checking the wifiex_sdio_probe_of()
return value.

Ok. I looked at 4.7 sources on lxr [1].

Oh, right. That was fixed quite recently indeed.
 

quoted

If the IRQ request failing is not an error, then at the very least the call
to disable_irq() should be avoided if request_irq() fails, and the message
should be changed from dev_err() to dev_dgb() or dev_info().

agree.

quoted

quoted

The device may still function without this wake interrupt.

That's correct, the binding says that the "interrupts" property in the child
node is optional since is just a wakeup IRQ. Now the question is if should
be an error if the IRQ is defined but fails to be requested.

Clearly it indicates an error in the DT specification so behavior is not
as expected. Personally I would indeed consider it an error, but I was
just indicating that it might have done like this intentionally.

Yes, might had been done intentionally indeed but I don't think that is
the case since the driver lacked error checking and propagation in many
places. But if someone thinks that's better to not honor the DT and at
least have the driver working without the wake up capability, then I'm
happy to respin the patch and change the print log level to info/debug.
 

Regards,
Arend

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

Javier Martinez Canillas [off-list ref] wrote:

If request_irq() fails in mwifiex_sdio_probe_of(), only an error message
is printed but the actual error is not propagated to the caller function.

Signed-off-by: Javier Martinez Canillas <redacted>

What's the conclusion with this patch? Should I drop it or take it?

(The discussion is available from the patchwork link in the signature.)

-- 
Sent by pwcli
https://patchwork.kernel.org/patch/9288169/