2018-07-27 08:43:19

by Jia-Ju Bai

[permalink] [raw]
Subject: [PATCH] net: usb: sr9700: Replace mdelay() with msleep() in sr9700_bind()

sr9700_bind() is never called in atomic context.
It calls mdelay() to busily wait, which is not necessary.
mdelay() can be replaced with msleep().

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <[email protected]>
---
drivers/net/usb/sr9700.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c
index 2d316c1b851b..6ac232e52bf7 100644
--- a/drivers/net/usb/sr9700.c
+++ b/drivers/net/usb/sr9700.c
@@ -358,7 +358,7 @@ static int sr9700_bind(struct usbnet *dev, struct usb_interface *intf)
/* power up and reset phy */
sr_write_reg(dev, SR_PRR, PRR_PHY_RST);
/* at least 10ms, here 20ms for safe */
- mdelay(20);
+ msleep(20);
sr_write_reg(dev, SR_PRR, 0);
/* at least 1ms, here 2ms for reading right register */
udelay(2 * 1000);
--
2.17.0



2018-07-27 09:06:15

by [email protected]

[permalink] [raw]
Subject: Re: [PATCH] net: usb: sr9700: Replace mdelay() with msleep() in sr9700_bind()

Dear Jia-Ju Bai :

OK.

the patch is ok.



[email protected]

From: Jia-Ju Bai
Date: 2018-07-27 16:41
To: liujunliang_ljl
CC: linux-usb; netdev; linux-kernel; Jia-Ju Bai
Subject: [PATCH] net: usb: sr9700: Replace mdelay() with msleep() in sr9700_bind()
sr9700_bind() is never called in atomic context.
It calls mdelay() to busily wait, which is not necessary.
mdelay() can be replaced with msleep().

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <[email protected]>
---
drivers/net/usb/sr9700.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c
index 2d316c1b851b..6ac232e52bf7 100644
--- a/drivers/net/usb/sr9700.c
+++ b/drivers/net/usb/sr9700.c
@@ -358,7 +358,7 @@ static int sr9700_bind(struct usbnet *dev, struct usb_interface *intf)
/* power up and reset phy */
sr_write_reg(dev, SR_PRR, PRR_PHY_RST);
/* at least 10ms, here 20ms for safe */
- mdelay(20);
+ msleep(20);
sr_write_reg(dev, SR_PRR, 0);
/* at least 1ms, here 2ms for reading right register */
udelay(2 * 1000);
--
2.17.0

2018-07-27 21:14:30

by David Miller

[permalink] [raw]
Subject: Re: [PATCH] net: usb: sr9700: Replace mdelay() with msleep() in sr9700_bind()

From: Jia-Ju Bai <[email protected]>
Date: Fri, 27 Jul 2018 16:41:04 +0800

> sr9700_bind() is never called in atomic context.
> It calls mdelay() to busily wait, which is not necessary.
> mdelay() can be replaced with msleep().
>
> This is found by a static analysis tool named DCNS written by myself.
>
> Signed-off-by: Jia-Ju Bai <[email protected]>

Applied.