[PATCH] staging: wfx: Replace udelay() by usleep_range() in bh.c

[PATCH] staging: wfx: Replace udelay() by usleep_range() in bh.c

[Fabio M. De Francesco]

Replace udelay() by usleep_range() in bh.c according to checkpatch
message: "CHECK: usleep_range is preferred over udelay"

Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
---
 drivers/staging/wfx/bh.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/wfx/bh.c b/drivers/staging/wfx/bh.c
index ed53d0b45592..07ef6732973d 100644
--- a/drivers/staging/wfx/bh.c
+++ b/drivers/staging/wfx/bh.c
@@ -315,7 +315,7 @@ void wfx_bh_poll_irq(struct wfx_dev *wdev)
 			dev_err(wdev->dev, "time out while polling control register\n");
 			return;
 		}
-		udelay(200);
+		usleep_range(200, 300);
 	}
 	wfx_bh_request_rx(wdev);
 }
-- 
2.30.2

Re: [PATCH] staging: wfx: Replace udelay() by usleep_range() in bh.c

[Greg KH]

On Mon, Apr 05, 2021 at 11:52:13AM +0200, Fabio M. De Francesco wrote:
> Replace udelay() by usleep_range() in bh.c according to checkpatch
> message: "CHECK: usleep_range is preferred over udelay"
> 
> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
> ---
>  drivers/staging/wfx/bh.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/wfx/bh.c b/drivers/staging/wfx/bh.c
> index ed53d0b45592..07ef6732973d 100644
> --- a/drivers/staging/wfx/bh.c
> +++ b/drivers/staging/wfx/bh.c
> @@ -315,7 +315,7 @@ void wfx_bh_poll_irq(struct wfx_dev *wdev)
>  			dev_err(wdev->dev, "time out while polling control register\n");
>  			return;
>  		}
> -		udelay(200);
> +		usleep_range(200, 300);

Do you know that this range is safe to use?  This type of change needs
to be tested on a device itself.

thanks,

greg k-h

Re: [PATCH] staging: wfx: Replace udelay() by usleep_range() in bh.c

[FMDF]

Thanks for your prompt reply. No, I don't know it for sure. I've just
read some drivers and found that often the maximum time is about 150%
of the minimum. I assumed (wrongly) that it was safe.

Can I leave usleep_range() with 200 usec for min and max time, as it
was with udelay(), and let the maintainer to take care of the numbers?

Kind regards,

Fabio

On Mon, Apr 5, 2021 at 12:03 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Mon, Apr 05, 2021 at 11:52:13AM +0200, Fabio M. De Francesco wrote:
> > Replace udelay() by usleep_range() in bh.c according to checkpatch
> > message: "CHECK: usleep_range is preferred over udelay"
> >
> > Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
> > ---
> >  drivers/staging/wfx/bh.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/staging/wfx/bh.c b/drivers/staging/wfx/bh.c
> > index ed53d0b45592..07ef6732973d 100644
> > --- a/drivers/staging/wfx/bh.c
> > +++ b/drivers/staging/wfx/bh.c
> > @@ -315,7 +315,7 @@ void wfx_bh_poll_irq(struct wfx_dev *wdev)
> >                       dev_err(wdev->dev, "time out while polling control register\n");
> >                       return;
> >               }
> > -             udelay(200);
> > +             usleep_range(200, 300);
>
> Do you know that this range is safe to use?  This type of change needs
> to be tested on a device itself.
>
> thanks,
>
> greg k-h

Re: [PATCH] staging: wfx: Replace udelay() by usleep_range() in bh.c

[Greg KH]

A: http://en.wikipedia.org/wiki/Top_post
Q: Were do I find info about this thing called top-posting?
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?

A: No.
Q: Should I include quotations after my reply?

http://daringfireball.net/2007/07/on_top

On Mon, Apr 05, 2021 at 12:15:17PM +0200, FMDF wrote:
> Thanks for your prompt reply. No, I don't know it for sure. I've just
> read some drivers and found that often the maximum time is about 150%
> of the minimum. I assumed (wrongly) that it was safe.
> 
> Can I leave usleep_range() with 200 usec for min and max time, as it
> was with udelay(), and let the maintainer to take care of the numbers?

I would just leave it as-is for now, no need to change it.

thanks,

greg k-h