From 1cf0c6e69e396538615153056605aaafab11935a Mon Sep 17 00:00:00 2001 From: Henrik Rydberg Date: Mon, 6 Feb 2012 08:49:25 +0100 Subject: Input: Add EVIOC mechanism for MT slots This patch adds the ability to extract MT slot data via a new ioctl, EVIOCGMTSLOTS. The function returns an array of slot values for the specified ABS_MT event type. Example of user space usage: struct { unsigned code; int values[64]; } req; req.code = ABS_MT_POSITION_X; if (ioctl(fd, EVIOCGMTSLOTS(sizeof(req)), &req) < 0) return -1; for (i = 0; i < 64; i++) printf("slot %d: %d\n", i, req.values[i]); Reviewed-by: Chase Douglas Signed-off-by: Henrik Rydberg --- include/linux/input.h | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'include/linux/input.h') diff --git a/include/linux/input.h b/include/linux/input.h index 3862e32c4eeb..af264438631d 100644 --- a/include/linux/input.h +++ b/include/linux/input.h @@ -114,6 +114,31 @@ struct input_keymap_entry { #define EVIOCGUNIQ(len) _IOC(_IOC_READ, 'E', 0x08, len) /* get unique identifier */ #define EVIOCGPROP(len) _IOC(_IOC_READ, 'E', 0x09, len) /* get device properties */ +/** + * EVIOCGMTSLOTS(len) - get MT slot values + * + * The ioctl buffer argument should be binary equivalent to + * + * struct input_mt_request_layout { + * __u32 code; + * __s32 values[num_slots]; + * }; + * + * where num_slots is the (arbitrary) number of MT slots to extract. + * + * The ioctl size argument (len) is the size of the buffer, which + * should satisfy len = (num_slots + 1) * sizeof(__s32). If len is + * too small to fit all available slots, the first num_slots are + * returned. + * + * Before the call, code is set to the wanted ABS_MT event type. On + * return, values[] is filled with the slot values for the specified + * ABS_MT code. + * + * If the request code is not an ABS_MT value, -EINVAL is returned. + */ +#define EVIOCGMTSLOTS(len) _IOC(_IOC_READ, 'E', 0x0a, len) + #define EVIOCGKEY(len) _IOC(_IOC_READ, 'E', 0x18, len) /* get global key state */ #define EVIOCGLED(len) _IOC(_IOC_READ, 'E', 0x19, len) /* get all LEDs */ #define EVIOCGSND(len) _IOC(_IOC_READ, 'E', 0x1a, len) /* get all sounds status */ -- cgit