adv7511_probe() is never called in atomic context.
This function is only set as ".probe" in struct i2c_driver.
Despite never getting called from atomic context, adv7511_probe()
calls mdelay() to busily wait.
This is not necessary and can be replaced with usleep_range() 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 <[email protected]>
---
drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index b2431ae..2cf7fa1 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -1054,7 +1054,7 @@ static int adv7511_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
}
if (adv7511->gpio_pd) {
- mdelay(5);
+ usleep_range(5000, 6000);
gpiod_set_value_cansleep(adv7511->gpio_pd, 0);
}
--
1.9.1
Hi Jia-Ju,
Thank you for the patch.
On Wednesday, 11 April 2018 11:33:42 EEST Jia-Ju Bai wrote:
> adv7511_probe() is never called in atomic context.
> This function is only set as ".probe" in struct i2c_driver.
>
> Despite never getting called from atomic context, adv7511_probe()
> calls mdelay() to busily wait.
> This is not necessary and can be replaced with usleep_range() to
> avoid busy waiting.
>
> This is found by a static analysis tool named DCNS written by myself.
> And I also manually check it.
Nice work ! Is the tool open-source ?
> Signed-off-by: Jia-Ju Bai <[email protected]>
> ---
> drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c index b2431ae..2cf7fa1
> 100644
> --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> @@ -1054,7 +1054,7 @@ static int adv7511_probe(struct i2c_client *i2c, const
> struct i2c_device_id *id) }
>
> if (adv7511->gpio_pd) {
> - mdelay(5);
> + usleep_range(5000, 6000);
> gpiod_set_value_cansleep(adv7511->gpio_pd, 0);
> }
The patch looks good to me.
Reviewed-by: Laurent Pinchart <[email protected]>
--
Regards,
Laurent Pinchart
On Friday 27 April 2018 03:46 AM, Laurent Pinchart wrote:
> Hi Jia-Ju,
>
> Thank you for the patch.
>
> On Wednesday, 11 April 2018 11:33:42 EEST Jia-Ju Bai wrote:
>> adv7511_probe() is never called in atomic context.
>> This function is only set as ".probe" in struct i2c_driver.
>>
>> Despite never getting called from atomic context, adv7511_probe()
>> calls mdelay() to busily wait.
>> This is not necessary and can be replaced with usleep_range() to
>> avoid busy waiting.
>>
>> This is found by a static analysis tool named DCNS written by myself.
>> And I also manually check it.
>
> Nice work ! Is the tool open-source ?
>
>> Signed-off-by: Jia-Ju Bai <[email protected]>
>> ---
>> drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
>> b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c index b2431ae..2cf7fa1
>> 100644
>> --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
>> +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
>> @@ -1054,7 +1054,7 @@ static int adv7511_probe(struct i2c_client *i2c, const
>> struct i2c_device_id *id) }
>>
>> if (adv7511->gpio_pd) {
>> - mdelay(5);
>> + usleep_range(5000, 6000);
>> gpiod_set_value_cansleep(adv7511->gpio_pd, 0);
>> }
>
> The patch looks good to me.
>
> Reviewed-by: Laurent Pinchart <[email protected]>
queued to drm-misc-next
Thanks,
Archit