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* [PATCH] base/platform: Fix platform drivers with no probe callback (ex alarmtimer)
@ 2016-01-04 18:17 Martin Fuzzey
  2016-01-05  8:43 ` Uwe Kleine-König
  0 siblings, 1 reply; 5+ messages in thread
From: Martin Fuzzey @ 2016-01-04 18:17 UTC (permalink / raw)
  To: Greg Kroah-Hartman, Uwe Kleine-König; +Cc: linux-kernel

Normally, when a platform driver defines a .probe callback, the
result of dev_pm_domain_attach() is ignored unless it is EPROBE_DEFER.

However, when a .probe callback is not defined the result of
dev_pm_domain_attach() is propagated to the caller.

But dev_pm_domain_attach() can return -ENODEV for devices with no
power domain.

This was causing the alarmtimer .suspend() callback to be ignored
and hence alarms not to wake from suspend (since the RTC was
not being programmed on suspend).

Fixes: b8b2c7d [base/platform: assert that dev_pm_domain callbacks are called unconditionally]
Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
---
 drivers/base/platform.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 1dd6d3b..61e5b7e 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -513,8 +513,8 @@ static int platform_drv_probe(struct device *_dev)
 		return ret;
 
 	ret = dev_pm_domain_attach(_dev, true);
-	if (ret != -EPROBE_DEFER && drv->probe) {
-		ret = drv->probe(dev);
+	if (ret != -EPROBE_DEFER) {
+		ret = drv->probe ? drv->probe(dev) : 0;
 		if (ret)
 			dev_pm_domain_detach(_dev, true);
 	}


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH] base/platform: Fix platform drivers with no probe callback (ex alarmtimer)
  2016-01-04 18:17 [PATCH] base/platform: Fix platform drivers with no probe callback (ex alarmtimer) Martin Fuzzey
@ 2016-01-05  8:43 ` Uwe Kleine-König
  2016-01-05 10:02   ` Tero Roponen
  2016-01-05 11:14   ` Martin Fuzzey
  0 siblings, 2 replies; 5+ messages in thread
From: Uwe Kleine-König @ 2016-01-05  8:43 UTC (permalink / raw)
  To: Martin Fuzzey; +Cc: Greg Kroah-Hartman, linux-kernel

Hello,

I think this is the same problem that another Martin found and fixed in

http://mid.gmane.org/1449132704-9952-1-git-send-email-martin.wilck@ts.fujitsu.com

I didn't check, but thought Greg already picked that up?!

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH] base/platform: Fix platform drivers with no probe callback (ex alarmtimer)
  2016-01-05  8:43 ` Uwe Kleine-König
@ 2016-01-05 10:02   ` Tero Roponen
  2016-01-05 13:02     ` Uwe Kleine-König
  2016-01-05 11:14   ` Martin Fuzzey
  1 sibling, 1 reply; 5+ messages in thread
From: Tero Roponen @ 2016-01-05 10:02 UTC (permalink / raw)
  To: Uwe Kleine-König; +Cc: Martin Fuzzey, Greg Kroah-Hartman, linux-kernel

[-- Attachment #1: Type: text/plain, Size: 598 bytes --]


On Tue, 5 Jan 2016, Uwe Kleine-König wrote:

> Hello,
> 
> I think this is the same problem that another Martin found and fixed in
> 
> http://mid.gmane.org/1449132704-9952-1-git-send-email-martin.wilck@ts.fujitsu.com
> 
> I didn't check, but thought Greg already picked that up?!

I can confirm that applying the patch in that link to 4.4-rc8 fixes the
following problem I've seen since 4.4-rc5:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000e20
IP: [<ffffffffa017835e>] asus_sysfs_is_visible+0xe/0x1d0 [asus_laptop]

So:

Tested-by: Tero Roponen <tero.roponen@gmail.com>

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH] base/platform: Fix platform drivers with no probe callback (ex alarmtimer)
  2016-01-05  8:43 ` Uwe Kleine-König
  2016-01-05 10:02   ` Tero Roponen
@ 2016-01-05 11:14   ` Martin Fuzzey
  1 sibling, 0 replies; 5+ messages in thread
From: Martin Fuzzey @ 2016-01-05 11:14 UTC (permalink / raw)
  To: Uwe Kleine-König; +Cc: Greg Kroah-Hartman, linux-kernel

Hi Uwe,

On 05/01/16 09:43, Uwe Kleine-König wrote:
> Hello,
>
> I think this is the same problem that another Martin found and fixed in
>
> http://mid.gmane.org/1449132704-9952-1-git-send-email-martin.wilck@ts.fujitsu.com

Yes it's the same problem and the fix is equivalent to my patch
> I didn't check, but thought Greg already picked that up?!

It's not in 4.4-rc8

Regards,

Martin

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH] base/platform: Fix platform drivers with no probe callback (ex alarmtimer)
  2016-01-05 10:02   ` Tero Roponen
@ 2016-01-05 13:02     ` Uwe Kleine-König
  0 siblings, 0 replies; 5+ messages in thread
From: Uwe Kleine-König @ 2016-01-05 13:02 UTC (permalink / raw)
  To: Tero Roponen; +Cc: Martin Fuzzey, Greg Kroah-Hartman, linux-kernel

On Tue, Jan 05, 2016 at 12:02:23PM +0200, Tero Roponen wrote:
> 
> On Tue, 5 Jan 2016, Uwe Kleine-König wrote:
> 
> > Hello,
> > 
> > I think this is the same problem that another Martin found and fixed in
> > 
> > http://mid.gmane.org/1449132704-9952-1-git-send-email-martin.wilck@ts.fujitsu.com
> > 
> > I didn't check, but thought Greg already picked that up?!
> 
> I can confirm that applying the patch in that link to 4.4-rc8 fixes the
> following problem I've seen since 4.4-rc5:
> 
> BUG: unable to handle kernel NULL pointer dereference at 0000000000000e20
> IP: [<ffffffffa017835e>] asus_sysfs_is_visible+0xe/0x1d0 [asus_laptop]

This is a separate bug however that is worth fixing, too. I guess this
is similar to the tpm problem my broken patch made obvious.

Best regards
Uwe


-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2016-01-05 13:02 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-01-04 18:17 [PATCH] base/platform: Fix platform drivers with no probe callback (ex alarmtimer) Martin Fuzzey
2016-01-05  8:43 ` Uwe Kleine-König
2016-01-05 10:02   ` Tero Roponen
2016-01-05 13:02     ` Uwe Kleine-König
2016-01-05 11:14   ` Martin Fuzzey

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