forked from Minki/linux
c4b5be98fe
A few architectures, like OMAP, allow you to set a debouncing time for the gpio before generating the IRQ. Teach gpiolib about that. Mark said: : This would be generally useful for embedded systems, especially where : the interrupt concerned is a wake source. It allows drivers to avoid : spurious interrupts from noisy sources so if the hardware supports it : the driver can avoid having to explicitly wait for the signal to become : stable and software has to cope with fewer events. We've lived without : it for quite some time, though. David said: : I looked at adding debounce support to the generic GPIO calls (and thus : gpiolib) some time back, but decided against it. I forget why at this : time (check list archives) but it wasn't because of lack of utility in : certain contexts. : : One thing to watch out for is just how variable the hardware capabilities : are. Atmel GPIOs have something like a fixed number of 32K clock cycles : for debounce, twl4030 had something odd, OMAPs were more like the Atmel : chips but with a different clock. In some cases debouncing had to be : ganged, not per-GPIO. And so forth. Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com> Cc: Tony Lindgren <tony@atomide.com> Cc: David Brownell <david-b@pacbell.net> Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| adp5520-gpio.c | ||
| adp5588-gpio.c | ||
| bt8xxgpio.c | ||
| cs5535-gpio.c | ||
| gpiolib.c | ||
| it8761e_gpio.c | ||
| Kconfig | ||
| langwell_gpio.c | ||
| Makefile | ||
| max730x.c | ||
| max732x.c | ||
| max7300.c | ||
| max7301.c | ||
| mc33880.c | ||
| mcp23s08.c | ||
| pca953x.c | ||
| pcf857x.c | ||
| pl061.c | ||
| sch_gpio.c | ||
| timbgpio.c | ||
| twl4030-gpio.c | ||
| ucb1400_gpio.c | ||
| vr41xx_giu.c | ||
| wm831x-gpio.c | ||
| wm8350-gpiolib.c | ||
| wm8994-gpio.c | ||
| xilinx_gpio.c | ||