staging: nvec: Fix usleep_range is preferred over udelay

Message ID 20171129160002.GA26462@josharch
State New
Headers show
Series
  • staging: nvec: Fix usleep_range is preferred over udelay
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Commit Message

Josh Abraham Nov. 29, 2017, 4 p.m.
Signed-off-by: Joshua Abraham <j.abraham1776@gmail.com>

This patch fixes the issue:

CHECK: usleep_range is preferred over udelay; see
Documentation/timers/timers-howto.txt

---
 drivers/staging/nvec/nvec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Mikko Perttunen Nov. 29, 2017, 4:07 p.m. | #1
On 11/29/2017 06:00 PM, Joshua Abraham wrote:
> Signed-off-by: Joshua Abraham <j.abraham1776@gmail.com>
> 
> This patch fixes the issue:
> 
> CHECK: usleep_range is preferred over udelay; see
> Documentation/timers/timers-howto.txt
> 
> ---
>   drivers/staging/nvec/nvec.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/nvec/nvec.c b/drivers/staging/nvec/nvec.c
> index 4ff8f47385da..2a01ef4b54ff 100644
> --- a/drivers/staging/nvec/nvec.c
> +++ b/drivers/staging/nvec/nvec.c
> @@ -631,7 +631,7 @@ static irqreturn_t nvec_interrupt(int irq, void *dev)
>   		break;
>   	case 2:		/* first byte after command */
>   		if (status == (I2C_SL_IRQ | RNW | RCVD)) {
> -			udelay(33);
> +			usleep_range(30, 35);
>   			if (nvec->rx->data[0] != 0x01) {
>   				dev_err(nvec->dev,
>   					"Read without prior read command\n");
> 

This is incorrect, as this function is an interrupt handler and we 
cannot sleep in interrupt context.

Cheers,
Mikko
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Josh Abraham Nov. 29, 2017, 4:17 p.m. | #2
On Wed, Nov 29, 2017 at 06:07:53PM +0200, Mikko Perttunen wrote:
> On 11/29/2017 06:00 PM, Joshua Abraham wrote:
> > Signed-off-by: Joshua Abraham <j.abraham1776@gmail.com>
> > 
> > This patch fixes the issue:
> > 
> > CHECK: usleep_range is preferred over udelay; see
> > Documentation/timers/timers-howto.txt
> > 
> > ---
> >   drivers/staging/nvec/nvec.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/staging/nvec/nvec.c b/drivers/staging/nvec/nvec.c
> > index 4ff8f47385da..2a01ef4b54ff 100644
> > --- a/drivers/staging/nvec/nvec.c
> > +++ b/drivers/staging/nvec/nvec.c
> > @@ -631,7 +631,7 @@ static irqreturn_t nvec_interrupt(int irq, void *dev)
> >   		break;
> >   	case 2:		/* first byte after command */
> >   		if (status == (I2C_SL_IRQ | RNW | RCVD)) {
> > -			udelay(33);
> > +			usleep_range(30, 35);
> >   			if (nvec->rx->data[0] != 0x01) {
> >   				dev_err(nvec->dev,
> >   					"Read without prior read command\n");
> > 
> 
> This is incorrect, as this function is an interrupt handler and we cannot
> sleep in interrupt context.
> 
> Cheers,
> Mikko

My mistake.  Thank you for the feedback!
-Josh
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Patch

diff --git a/drivers/staging/nvec/nvec.c b/drivers/staging/nvec/nvec.c
index 4ff8f47385da..2a01ef4b54ff 100644
--- a/drivers/staging/nvec/nvec.c
+++ b/drivers/staging/nvec/nvec.c
@@ -631,7 +631,7 @@  static irqreturn_t nvec_interrupt(int irq, void *dev)
 		break;
 	case 2:		/* first byte after command */
 		if (status == (I2C_SL_IRQ | RNW | RCVD)) {
-			udelay(33);
+			usleep_range(30, 35);
 			if (nvec->rx->data[0] != 0x01) {
 				dev_err(nvec->dev,
 					"Read without prior read command\n");