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From: Sunny Kumar <sunny.kumar.roy@gmail.com>
To: mdharm-usb@one-eyed-alien.net, gregkh@linuxfoundation.org,
	linux-usb@vger.kernel.org, usb-storage@lists.one-eyed-alien.net,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1] usb: usleep_range is preferred over udelay where wakeup is flexible
Date: Wed, 24 Jun 2015 21:15:03 +0530	[thread overview]
Message-ID: <20150624154503.GA2557@sunny-DevBox> (raw)
In-Reply-To: <1435128869-20263-1-git-send-email-sunny.kumar.roy@gmail.com>

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Ok then,
This might be the final lower and upper limit value.

Sunny Kumar

On Wed, Jun 24, 2015 at 12:24:29PM +0530, Sunny Kumar wrote:
> According to Documentation/timers/timers-howto.txt"
> udelay() is only called once from a place where sleeping is allowed.
> We can replace it with a call to usleep_range()
> with a reasonable upper limit.
> 
> Signed-off-by: Sunny Kumar <sunny.kumar.roy@gmail.com>
> ---
>  drivers/usb/storage/transport.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c
> index 540add2..7cd45ac 100644
> --- a/drivers/usb/storage/transport.c
> +++ b/drivers/usb/storage/transport.c
> @@ -1111,7 +1111,7 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
>  	 * command phase and the data phase.  Some devices need a little
>  	 * more than that, probably because of clock rate inaccuracies. */
>  	if (unlikely(us->fflags & US_FL_GO_SLOW))
> -		udelay(125);
> +		usleep_range(100, 125);
>  
>  	if (transfer_length) {
>  		unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ? 
> -- 
> 2.1.4
> 

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[-- Type: text/x-diff, Size: 1202 bytes --]

>From 62bc3514ec4da51e7e766199d00de0594b17d23b Mon Sep 17 00:00:00 2001
From: Sunny Kumar <sunny.kumar.roy@gmail.com>
Date: Wed, 24 Jun 2015 21:07:18 +0530
Subject: [PATCH 1/1] usb: usleep_range is preferred over udelay where wakeup
 is flexible

According to Documentation/timers/timers-howto.txt"
udelay() is only called once from a place where sleeping is allowed.
We can replace it with a call to usleep_range()
with a reasonable upper limit.

Signed-off-by: Sunny Kumar <sunny.kumar.roy@gmail.com>
---
 drivers/usb/storage/transport.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c
index 540add2..5e67f63 100644
--- a/drivers/usb/storage/transport.c
+++ b/drivers/usb/storage/transport.c
@@ -1111,7 +1111,7 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
 	 * command phase and the data phase.  Some devices need a little
 	 * more than that, probably because of clock rate inaccuracies. */
 	if (unlikely(us->fflags & US_FL_GO_SLOW))
-		udelay(125);
+		usleep_range(125, 150);
 
 	if (transfer_length) {
 		unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ? 
-- 
1.9.1


  parent reply	other threads:[~2015-06-24 15:45 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-06-24  6:54 [PATCH 1/1] usb: usleep_range is preferred over udelay where wakeup is flexible Sunny Kumar
2015-06-24 13:44 ` Alan Stern
2015-06-24 14:28 ` Sunny Kumar
2015-06-24 14:35   ` Alan Stern
2015-06-24 15:45 ` Sunny Kumar [this message]
2015-06-25 15:30 ` Sunny Kumar

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