From a80b83b7b8456e9b475346c2e01d7e210883208c Mon Sep 17 00:00:00 2001 From: John Stultz Date: Fri, 3 Feb 2012 00:19:07 -0800 Subject: Input: add infrastructure for selecting clockid for event time stamps As noted by Arve and others, since wall time can jump backwards, it is difficult to use for input because one cannot determine if one event occurred before another or for how long a key was pressed. However, the timestamp field is part of the kernel ABI, and cannot be changed without possibly breaking existing users. This patch adds a new IOCTL that allows a clockid to be set in the evdev_client struct that will specify which time base to use for event timestamps (ie: CLOCK_MONOTONIC instead of CLOCK_REALTIME). For now we only support CLOCK_MONOTONIC and CLOCK_REALTIME, but in the future we could support other clockids if appropriate. The default remains CLOCK_REALTIME, so we don't change the ABI. Signed-off-by: John Stultz Reviewed-by: Daniel Kurtz Signed-off-by: Dmitry Torokhov --- include/linux/input.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux/input.h') diff --git a/include/linux/input.h b/include/linux/input.h index 3862e32c4eeb..177261ea6f52 100644 --- a/include/linux/input.h +++ b/include/linux/input.h @@ -129,6 +129,8 @@ struct input_keymap_entry { #define EVIOCGRAB _IOW('E', 0x90, int) /* Grab/Release device */ +#define EVIOCSCLOCKID _IOW('E', 0xa0, int) /* Set clockid to be used for timestamps */ + /* * Device properties and quirks */ -- cgit v1.2.3 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 v1.2.3