Changing direction of character device line
As Linus presented in Linux conference, we should now use new character device instead of /sys/class/gpio. By using SFS, you could change direction of a pin by writing in or out to the /gpioN/direction. I can't find a simpler way in new character device than than closing the descriptor and request the same line again with different flag:
struct gpiohandle_request req;
req.flags = GPIOHANDLE_REQUEST_INPUT;
ioctl(fd_chip, GPIO_GET_LINEHANDLE_IOCTL, &req);
// do some stuff
close(req.fd);
req.flags = GPIOHANDLE_REQUEST_OUTPUT;
ioctl(fd_chip, GPIO_GET_LINEHANDLE_IOCTL, &req);
What's the prefered way of doing it?
gpio
asked Feb 13 at 19:00
QuestQuest
1,60311331
migrated from unix.stackexchange.com Feb 15 at 10:24
This question came from our site for users of Linux, FreeBSD and other Un*x-like operating systems.
add a comment |
As Linus presented in Linux conference, we should now use new character device instead of /sys/class/gpio. By using SFS, you could change direction of a pin by writing in or out to the /gpioN/direction. I can't find a simpler way in new character device than than closing the descriptor and request the same line again with different flag:
struct gpiohandle_request req;
req.flags = GPIOHANDLE_REQUEST_INPUT;
ioctl(fd_chip, GPIO_GET_LINEHANDLE_IOCTL, &req);
// do some stuff
close(req.fd);
req.flags = GPIOHANDLE_REQUEST_OUTPUT;
ioctl(fd_chip, GPIO_GET_LINEHANDLE_IOCTL, &req);
What's the prefered way of doing it?
gpio
asked Feb 13 at 19:00
QuestQuest
1,60311331
migrated from unix.stackexchange.com Feb 15 at 10:24
This question came from our site for users of Linux, FreeBSD and other Un*x-like operating systems.
add a comment |
As Linus presented in Linux conference, we should now use new character device instead of /sys/class/gpio. By using SFS, you could change direction of a pin by writing in or out to the /gpioN/direction. I can't find a simpler way in new character device than than closing the descriptor and request the same line again with different flag:
struct gpiohandle_request req;
req.flags = GPIOHANDLE_REQUEST_INPUT;
ioctl(fd_chip, GPIO_GET_LINEHANDLE_IOCTL, &req);
// do some stuff
close(req.fd);
req.flags = GPIOHANDLE_REQUEST_OUTPUT;
ioctl(fd_chip, GPIO_GET_LINEHANDLE_IOCTL, &req);
What's the prefered way of doing it?
gpio
asked Feb 13 at 19:00
QuestQuest
1,60311331
As Linus presented in Linux conference, we should now use new character device instead of /sys/class/gpio. By using SFS, you could change direction of a pin by writing in or out to the /gpioN/direction. I can't find a simpler way in new character device than than closing the descriptor and request the same line again with different flag:
struct gpiohandle_request req;
req.flags = GPIOHANDLE_REQUEST_INPUT;
ioctl(fd_chip, GPIO_GET_LINEHANDLE_IOCTL, &req);
// do some stuff
close(req.fd);
req.flags = GPIOHANDLE_REQUEST_OUTPUT;
ioctl(fd_chip, GPIO_GET_LINEHANDLE_IOCTL, &req);
What's the prefered way of doing it?
gpio
gpio
asked Feb 13 at 19:00
QuestQuest
1,60311331
asked Feb 13 at 19:00
QuestQuest
1,60311331
asked Feb 13 at 19:00
QuestQuest
1,60311331
asked Feb 13 at 19:00
QuestQuest
1,60311331
asked Feb 13 at 19:00
QuestQuest
1,60311331
1,60311331
migrated from unix.stackexchange.com Feb 15 at 10:24
This question came from our site for users of Linux, FreeBSD and other Un*x-like operating systems.
migrated from unix.stackexchange.com Feb 15 at 10:24
This question came from our site for users of Linux, FreeBSD and other Un*x-like operating systems.
add a comment |
add a comment |
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