Messages in this thread | | | Subject | Re: [PATCH RESEND] LEDS-One-Shot-Timer-Trigger-implementation | From | Shuah Khan <> | Date | Mon, 09 Apr 2012 10:55:49 -0600 |
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On Sat, 2012-04-07 at 14:56 -0700, Dmitry Torokhov wrote: > Hi Shuah, > > On Sat, Apr 07, 2012 at 08:13:44AM -0600, Shuah Khan wrote: > > > > > > +This feature will help implement vibrate functionality which requires one > > > > +time activation of vibrate mode without a continuous vibrate on/off cycles. > > > > > > They make vibrating LED? ;) > > > > > > What's going on here? You're proposing to repurpose the LEDs code to > > > drive vibration devices? Or some devices couple a LED with a vibration > > > device? > > > > I owe you filling in the blanks type explanation. Let me describe the > > use-case I am trying to address first. Vibrater function on phones is > > implemented using PWM pins on SoC or PMIC. When there is no such > > hardware present, a software solution is needed. Currently two drivers > > timed-gpio and timed-output (under staging/android in Linux 3.3) > > together implement the software vibrate feature. The main functionality > > it implements is the one time enables of timer to prevent user space > > crashes leaving the phone in vibrate mode causing the battery to drain. > > leds as it is implemented currently, is not suitable to address this > > use-case as it doesn't support one time enables. > > So why do not you use memoryless force feedback framework that other > devices use (see drivers/input/misc/*vibra.c drivers). >
Dimitry,
I took a look at these vibra* drivers. The three vibrate drivers are chip-set specific. The use-case I have is a non-chip set approach to address the use-case when vibrate hardware is not present. Are you envisioning a generic approach using ff-memoryless infrastructure?
-- Shuah
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