Re: [RFC 1/2] input: mt: Add method to extract the MT slot state
From: Henrik Rydberg <hidden>
Date: 2011-01-27 12:05:44
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Hi Benjamin, On Thu, Jan 27, 2011 at 11:35:46AM +0100, Benjamin Tissoires wrote:
This patch adds the function input_mt_get_abs_value(), which may be
Ehm, input_mt_get_absinfo?
used to extract the current state of the MT slots. Signed-off-by: Henrik Rydberg <redacted>
I had rather re-add this myself, thanks.
quoted hunk
Signed-off-by: Benjamin Tissoires <redacted> --- drivers/input/input-mt.c | 32 ++++++++++++++++++++++++++++++++ include/linux/input/mt.h | 1 + 2 files changed, 33 insertions(+), 0 deletions(-)diff --git a/drivers/input/input-mt.c b/drivers/input/input-mt.c index c48c81f..5b95e38 100644 --- a/drivers/input/input-mt.c +++ b/drivers/input/input-mt.c@@ -168,3 +168,35 @@ void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count) } } EXPORT_SYMBOL(input_mt_report_pointer_emulation); + +/** + * input_mt_get_absinfo - retrieve MT state variables from a device slot + * @dev: input device which state is being queried + * @code: ABS code to retrieve + * @slot: slot to retrieve from + * + * Return the ABS state of the given MT slot. If code is not an MT + * event, the corresponding ABS event is returned. + * + * This function may be called by anyone interested in extracting the + * current MT state. Used by evdev handlers. + */ +struct input_absinfo input_mt_get_absinfo(struct input_dev *dev, unsigned int code, int slot)
Why return the struct? Give it a pointer instead, so the return value can be used for errors. Also, I wonder about the usefulness of extracting the absinfo here - only the value depends on the slot argument, and absinfo does not require the same lock protection. Why not keep the layout from the original patch?
+{
+ unsigned int mtmap = code > ABS_MT_FIRST ? code - ABS_MT_FIRST : 0;Should rather return -EINVAL on bad argument.
+ unsigned long flags;
+ struct input_absinfo retval;
+
+ spin_lock_irqsave(&dev->event_lock, flags);
+ if (!mtmap)
+ retval = dev->absinfo[code];
+ else if (slot >= 0 && slot < dev->mtsize) {
+ retval = dev->absinfo[code];
+ retval.value = dev->mt[slot].abs[mtmap];Please use input_mt_get_value().
quoted hunk
+ } else + retval.value = 0; + spin_unlock_irqrestore(&dev->event_lock, flags); + + return retval; +} +EXPORT_SYMBOL(input_mt_get_absinfo);diff --git a/include/linux/input/mt.h b/include/linux/input/mt.h index b3ac06a..a71a27f 100644 --- a/include/linux/input/mt.h +++ b/include/linux/input/mt.h@@ -54,4 +54,5 @@ void input_mt_report_slot_state(struct input_dev *dev, void input_mt_report_finger_count(struct input_dev *dev, int count); void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count); +struct input_absinfo input_mt_get_absinfo(struct input_dev *dev, unsigned int code, int slot); #endif
Thanks, Henrik