I had to drop back by this thread after doing buttons with gpio_v2 and say the .debounce_period_us member to gpio_v2_line_attribute is the most ass-kickingly great feature yet! I have a bunch of miscellaneous switches that are horribly noisy and always a PITA to debounce. In the past I'd use interval timers disabling press detection for x-ms or try hardware debounce. The .debounce_period_us implementation is flawless. I tested with a noisy switch that I think I scavenged from one of my kids noise making stuffed animals years ago. Edge detection is 100% with a 5 ms (5000 us) debounce period.It is all in there - v2 is a strict super-set of v1. v1 grew organically and when I came along wanting to add debounce there was nowhere in the existing ioctls to put it. As new ioctls were in order it seemed like a good time to do a clean sweep and fix a bunch of other problems - like the odd object model that v1 had developed, e.g. edge detection requiring a separate request, and that only supporting a single line.
The setup was dead-bang simple just adding the attribute, e.g.
Code:
/* gpio_v2 attribute and attribute config setting button debounce to 5 ms. * for button gpio pin (offsets[0]) - adjust as needed) */ struct gpio_v2_line_attribute rd_attr = { .id = GPIO_V2_LINE_ATTR_ID_DEBOUNCE, .debounce_period_us = 5000 }; struct gpio_v2_line_config_attribute rd_cfg_attr = { .attr = rd_attr, .mask = 0x01 };Since your quoted paragraph was written in the first-person, a direct "thank you" is deserved. That was a stroke of genius.
Statistics: Posted by drankinatty — Mon May 27, 2024 8:21 pm