On 2018/4/12 0:19, Florian Fainelli wrote:
On 04/11/2018 12:14 AM, Jia-Ju Bai wrote:
On 2018/4/11 13:30, Phil Reid wrote:
On 11/04/2018 09:51, 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 mdelay() to busily wait.
This is not necessary and can be replaced with msleep() to
avoid busy waiting.
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 <baijiaju1...@gmail.com>
---
drivers/net/dsa/b53/b53_common.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/dsa/b53/b53_common.c
b/drivers/net/dsa/b53/b53_common.c
index 274f367..e070ff6 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -597,10 +597,10 @@ static void b53_switch_reset_gpio(struct
b53_device *dev)
/* Reset sequence: RESET low(50ms)->high(20ms)
*/
gpio_set_value(gpio, 0);
- mdelay(50);
+ msleep(50);
gpio_set_value(gpio, 1);
- mdelay(20);
+ msleep(20);
dev->current_page = 0xff;
}
Would that also imply gpio_set_value could be gpio_set_value_cansleep?
Yes, I think gpio_set_value_cansleep() is okay here?
Do I need to send a V2 patch to replace gpio_set_value()?
Yes, I would lump these two changes in the same patch since this is
effectively about solving sleeping vs. non sleeping operations.
Okay, I have sent a V2 patch, and you can have a look :)
Best wishes,
Jia-Ju Bai
