On Tue 2019-09-03 19:00:21, Oleh Kravchenko wrote: > Hello Pavel, > > 03.09.19 17:12, Pavel Machek пише: > > On Tue 2019-09-03 15:50:20, Oleh Kravchenko wrote: > >> Error was detected by PVS-Studio: > >> V792 The '__gpio_cansleep' function located to the right of > >> the operator '|' will be called regardless of the value of > >> the left operand. Perhaps, it is better to use '||'. > > 1st: original code is not wrong > > '|' is bitwise operation, if it really means *OR* then should be '||' - > led_dat->can_sleep is bool. I see that || would be more natural. But | also works. > > 2nd: you are introducing a bug > > No, because if GPIOs *slow* can sleep and GPIO *cmd* can't sleep > it will call gpio_set_value_cansleep() for both. If just one of them can sleep, can_sleep will be 0, and bad things will happen, right? > >> @@ -205,7 +205,7 @@ create_ns2_led(struct platform_device *pdev, struct ns2_led_data *led_dat, > >> led_dat->cdev.groups = ns2_led_groups; > >> led_dat->cmd = template->cmd; > >> led_dat->slow = template->slow; > >> - led_dat->can_sleep = gpio_cansleep(led_dat->cmd) | > >> + led_dat->can_sleep = gpio_cansleep(led_dat->cmd) && > >> gpio_cansleep(led_dat->slow); > >> if (led_dat->can_sleep) > >> led_dat->cdev.brightness_set_blocking = ns2_led_set_blocking; Best regards, Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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