[PATCH] pda_power: ac_draw used before set

[PATCH] pda_power: ac_draw used before set

[Paul Parsons]

When I reboot my iPAQ hx4700 in its cradle, the battery will not begin
to charge even though the AC supply is connected. Charging will start
only after the PDA power driver is tickled by some other power event,
such as reseating the iPAQ in its cradle or connecting the USB cable.

The problem lies in pda_power_probe(), where ac_draw is used by the call
to update_charger() before being set by the call to regulator_get().

Moving the regulator_get() call to before the update_charger() call
fixes the problem.

Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Cc: Philipp Zabel <philipp.zabel@gmail.com>
---
  drivers/power/pda_power.c |   16 +++++++++-------
  1 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/power/pda_power.c b/drivers/power/pda_power.c
index 7312f26..d3be834d 100644
--- a/drivers/power/pda_power.c
+++ b/drivers/power/pda_power.c
@@ -281,6 +281,14 @@ static int pda_power_probe(struct platform_device 
*pdev)
  			goto init_failed;
  	}

+	ac_draw = regulator_get(dev, "ac_draw");
+	if (IS_ERR(ac_draw)) {
+		dev_dbg(dev, "couldn't get ac_draw regulator\n");
+		ret = PTR_ERR(ac_draw);
+		ac_draw = NULL;
+		goto ac_draw_failed;
+	}
+
  	update_status();
  	update_charger();

@@ -309,13 +317,6 @@ static int pda_power_probe(struct platform_device 
*pdev)
  		pda_psy_usb.num_supplicants = pdata->num_supplicants;
  	}

-	ac_draw = regulator_get(dev, "ac_draw");
-	if (IS_ERR(ac_draw)) {
-		dev_dbg(dev, "couldn't get ac_draw regulator\n");
-		ac_draw = NULL;
-		ret = PTR_ERR(ac_draw);
-	}
-
  #ifdef CONFIG_USB_OTG_UTILS
  	transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
  	if (!IS_ERR_OR_NULL(transceiver)) {
@@ -415,6 +416,7 @@ ac_supply_failed:
  		regulator_put(ac_draw);
  		ac_draw = NULL;
  	}
+ac_draw_failed:
  	if (pdata->exit)
  		pdata->exit(dev);
  init_failed:
-- 
1.7.8.6

Re: [PATCH] pda_power: ac_draw used before set

[Anton Vorontsov]

On Wed, Sep 19, 2012 at 06:36:19PM +0100, Paul Parsons wrote:
> When I reboot my iPAQ hx4700 in its cradle, the battery will not begin
> to charge even though the AC supply is connected. Charging will start
> only after the PDA power driver is tickled by some other power event,
> such as reseating the iPAQ in its cradle or connecting the USB cable.
> 
> The problem lies in pda_power_probe(), where ac_draw is used by the call
> to update_charger() before being set by the call to regulator_get().
> 
> Moving the regulator_get() call to before the update_charger() call
> fixes the problem.
> 
> Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
> Cc: Philipp Zabel <philipp.zabel@gmail.com>
> ---

Great to see that someone is still using hx4700. :-)

Thanks for the patch, it is merged now!

Cheers,
Anton.

p.s.
The patch was mangled (word wrapped), but I fixed it up. Just fyi...

Re: [PATCH] pda_power: ac_draw used before set

[Paul Parsons]

Hello Anton,

On 20/09/12 22:32, Anton Vorontsov wrote:
> On Wed, Sep 19, 2012 at 06:36:19PM +0100, Paul Parsons wrote:
>> When I reboot my iPAQ hx4700 in its cradle, the battery will not begin
>> to charge even though the AC supply is connected. Charging will start
>> only after the PDA power driver is tickled by some other power event,
>> such as reseating the iPAQ in its cradle or connecting the USB cable.
>>
>> The problem lies in pda_power_probe(), where ac_draw is used by the call
>> to update_charger() before being set by the call to regulator_get().
>>
>> Moving the regulator_get() call to before the update_charger() call
>> fixes the problem.
>>
>> Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
>> Cc: Philipp Zabel <philipp.zabel@gmail.com>
>> ---
>
> Great to see that someone is still using hx4700. :-)
>
> Thanks for the patch, it is merged now!

I am having second thoughts about the goto ac_draw_failed I added.
This will cause pda_power_probe() to fail if regulator_get() fails.
However the way ac_draw is used - always after a check for NULL -
suggests that a failed call to regulator_get() was not fatal.

I am happy to submit another patch to remove the goto and label.

Regards,
Paul

Re: [PATCH] pda_power: ac_draw used before set

[Anton Vorontsov]

On Fri, Sep 21, 2012 at 01:16:38AM +0100, Paul Parsons wrote:
> >>When I reboot my iPAQ hx4700 in its cradle, the battery will not begin
> >>to charge even though the AC supply is connected. Charging will start
> >>only after the PDA power driver is tickled by some other power event,
> >>such as reseating the iPAQ in its cradle or connecting the USB cable.
> >>
> >>The problem lies in pda_power_probe(), where ac_draw is used by the call
> >>to update_charger() before being set by the call to regulator_get().
> >>
> >>Moving the regulator_get() call to before the update_charger() call
> >>fixes the problem.
> >>
> >>Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
> >>Cc: Philipp Zabel <philipp.zabel@gmail.com>
> >>---
> >
> >Great to see that someone is still using hx4700. :-)
> >
> >Thanks for the patch, it is merged now!
> 
> I am having second thoughts about the goto ac_draw_failed I added.
> This will cause pda_power_probe() to fail if regulator_get() fails.
> However the way ac_draw is used - always after a check for NULL -
> suggests that a failed call to regulator_get() was not fatal.
> 
> I am happy to submit another patch to remove the goto and label.

Sure thing, just send another patch on top.

Thanks!
Anton.