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 <[email protected]>
---
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;
}
--
1.9.1
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 <[email protected]>
> ---
> 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 <[email protected]>
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 <[email protected]>
Acked-by: Florian Fainelli <[email protected]>
--
Florian