[PATCH v7 02/11] thermal: armada: Use msleep for long delays

Miquel RAYNAL miquel.raynal at free-electrons.com
Mon Jan 1 23:42:40 PST 2018


Hello Eduardo,

On Mon, 1 Jan 2018 12:55:39 -0800
Eduardo Valentin <edubezval at gmail.com> wrote:

> On Fri, Dec 22, 2017 at 05:14:04PM +0100, Miquel Raynal wrote:
> > From: Baruch Siach <baruch at tkos.co.il>
> > 
> > Use msleep for long (> 10ms) delays, instead of the busy waiting
> > mdelay. All delays are called from the probe routine, where
> > scheduling is allowed.
> > 
> > Signed-off-by: Baruch Siach <baruch at tkos.co.il>
> > Signed-off-by: Miquel Raynal <miquel.raynal at free-electrons.com>
> > Reviewed-by: Gregory CLEMENT <gregory.clement at free-electrons.com>  
> 
> I am queueing this patch, however, ...
> 
> > ---
> >  drivers/thermal/armada_thermal.c | 8 ++++----
> >  1 file changed, 4 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/thermal/armada_thermal.c
> > b/drivers/thermal/armada_thermal.c index 706d74798cbe..6c4af2622d4f
> > 100644 --- a/drivers/thermal/armada_thermal.c
> > +++ b/drivers/thermal/armada_thermal.c
> > @@ -113,7 +113,7 @@ static void armada370_init_sensor(struct
> > platform_device *pdev, reg &= ~PMU_TDC0_START_CAL_MASK;
> >  	writel(reg, priv->control);
> >  
> > -	mdelay(10);
> > +	msleep(10);  
> 
> I want to double check with you that msleep(10) is documented to reach
> up to 20ms, see:
> 
> 
> WARNING: msleep < 20ms can sleep for up to 20ms; see
> Documentation/timers/timers-howto.txt #43: FILE:
> drivers/thermal/armada_thermal.c:116:
> +	msleep(10);
> 
> WARNING: msleep < 20ms can sleep for up to 20ms; see
> Documentation/timers/timers-howto.txt #66: FILE:
> drivers/thermal/armada_thermal.c:146:
> +		msleep(10);
> 
> Just want to check that you are aware of this and that it won't cause
> troubles in the code flows changed in this patch. Driver is still in
> one piece, correct?

Thanks for queueing the series.

All of these delays are here to ensure that we do wait a minimum
amount of time to let the hardware be ready, IMHO waiting up to 20ms is
not an issue.

Best regards,
Miquèl

> 
> >  }
> >  
> >  static void armada375_init_sensor(struct platform_device *pdev,
> > @@ -127,11 +127,11 @@ static void armada375_init_sensor(struct
> > platform_device *pdev, reg &= ~A375_HW_RESETn;
> >  
> >  	writel(reg, priv->control + 4);
> > -	mdelay(20);
> > +	msleep(20);
> >  
> >  	reg |= A375_HW_RESETn;
> >  	writel(reg, priv->control + 4);
> > -	mdelay(50);
> > +	msleep(50);
> >  }
> >  
> >  static void armada380_init_sensor(struct platform_device *pdev,
> > @@ -143,7 +143,7 @@ static void armada380_init_sensor(struct
> > platform_device *pdev, if (!(reg & A380_HW_RESET)) {
> >  		reg |= A380_HW_RESET;
> >  		writel(reg, priv->control);
> > -		mdelay(10);
> > +		msleep(10);
> >  	}
> >  }
> >  
> > -- 
> > 2.11.0
> >   



-- 
Miquel Raynal, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com



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