Message ID | 1523497702-7200-1-git-send-email-baijiaju1990@gmail.com |
---|---|
State | Deferred, archived |
Delegated to: | David Miller |
Headers | show |
Series | [v2] net: dsa: b53: Using sleep-able operations in b53_switch_reset_gpio | expand |
On 12/04/2018 09:48, Jia-Ju Bai wrote: > b53_switch_reset_gpio() is never called in atomic context. > > The call chain ending up at b53_switch_reset_gpio() is: > [1] b53_switch_reset_gpio() <- b53_switch_reset() <- > b53_reset_switch() <- b53_setup() > > b53_switch_reset_gpio() is set as ".setup" in struct dsa_switch_ops. > This function is not called in atomic context. > > Despite never getting called from atomic context, b53_switch_reset_gpio() > calls non-sleep operations mdelay() and gpio_set_value(). > They are not necessary and can be replaced with msleep() > and gpio_set_value_cansleep(). > > This is found by a static analysis tool named DCNS written by myself. > And I also manually check it. > > Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> > --- > v2: > * Use gpio_set_value_cansleep() to replace gpio_set_value() additionally. > Thanks for Florian and Phil for good advice. > --- > drivers/net/dsa/b53/b53_common.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c > index 274f367..36cc60d 100644 > --- a/drivers/net/dsa/b53/b53_common.c > +++ b/drivers/net/dsa/b53/b53_common.c > @@ -596,11 +596,11 @@ static void b53_switch_reset_gpio(struct b53_device *dev) > > /* Reset sequence: RESET low(50ms)->high(20ms) > */ > - gpio_set_value(gpio, 0); > - mdelay(50); > + gpio_set_value_cansleep(gpio, 0); > + msleep(50); > > - gpio_set_value(gpio, 1); > - mdelay(20); > + gpio_set_value_cansleep(gpio, 1); > + msleep(20); > > dev->current_page = 0xff; > } > FWIW: Reviewed-by: Phil Reid <preid@electromag.com.au>
On 04/11/2018 06:48 PM, Jia-Ju Bai wrote: > b53_switch_reset_gpio() is never called in atomic context. > > The call chain ending up at b53_switch_reset_gpio() is: > [1] b53_switch_reset_gpio() <- b53_switch_reset() <- > b53_reset_switch() <- b53_setup() > > b53_switch_reset_gpio() is set as ".setup" in struct dsa_switch_ops. > This function is not called in atomic context. > > Despite never getting called from atomic context, b53_switch_reset_gpio() > calls non-sleep operations mdelay() and gpio_set_value(). > They are not necessary and can be replaced with msleep() > and gpio_set_value_cansleep(). > > This is found by a static analysis tool named DCNS written by myself. > And I also manually check it. > > Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com>
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c index 274f367..36cc60d 100644 --- a/drivers/net/dsa/b53/b53_common.c +++ b/drivers/net/dsa/b53/b53_common.c @@ -596,11 +596,11 @@ static void b53_switch_reset_gpio(struct b53_device *dev) /* Reset sequence: RESET low(50ms)->high(20ms) */ - gpio_set_value(gpio, 0); - mdelay(50); + gpio_set_value_cansleep(gpio, 0); + msleep(50); - gpio_set_value(gpio, 1); - mdelay(20); + gpio_set_value_cansleep(gpio, 1); + msleep(20); dev->current_page = 0xff; }
b53_switch_reset_gpio() is never called in atomic context. The call chain ending up at b53_switch_reset_gpio() is: [1] b53_switch_reset_gpio() <- b53_switch_reset() <- b53_reset_switch() <- b53_setup() b53_switch_reset_gpio() is set as ".setup" in struct dsa_switch_ops. This function is not called in atomic context. Despite never getting called from atomic context, b53_switch_reset_gpio() calls non-sleep operations mdelay() and gpio_set_value(). They are not necessary and can be replaced with msleep() and gpio_set_value_cansleep(). This is found by a static analysis tool named DCNS written by myself. And I also manually check it. Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> --- v2: * Use gpio_set_value_cansleep() to replace gpio_set_value() additionally. Thanks for Florian and Phil for good advice. --- drivers/net/dsa/b53/b53_common.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)