General Purposer Timers in Linux

I want to use any one of BeagleBoard GPIO144, 145 or 146 as a timer event capture to accurately capture the Start of Frame Detect on a wireless transceiver. Does anyone have any experience on how to use OMAP3530 GPTIMERs in Linux? If someone can point me to some examples of using GPTIMERs in Linux, that would be great.

Kind Regards,

John

I want to use any one of BeagleBoard GPIO144, 145 or 146 as a timer event capture to accurately capture the Start of Frame Detect on a wireless transceiver. Does anyone have any experience on how to use OMAP3530 GPTIMERs in Linux? If someone can point me to some examples of using GPTIMERs in Linux, that would be great.

~/kernel/arch/arm/mach-omap2/timer-gp.c will be helpful,

Regards,
Shankar

I want to use any one of BeagleBoard GPIO144, 145 or 146 as a timer event capture to accurately capture the Start of Frame Detect on a wireless transceiver. Does anyone have any experience on how to use OMAP3530 GPTIMERs in Linux? If someone can point me to some examples of using GPTIMERs in Linux, that would be great.

~/kernel/arch/arm/mach-omap2/timer-gp.c will be helpful,

Hi Shankar,

I’m not sure if I’m missing something, but this code looks like it will trigger an event based on an expired timer. What I’m looking for is a way to capture the value in the timer, which is triggered by an external GPIO event.

Regards,
Shankar

From: beagleboard@googlegroups.com [mailto:beagleboard@googlegroups.com] On Behalf Of Shankar Ganesh
Sent: Tuesday, September 29, 2009 9:46 PM
To: beagleboard@googlegroups.com
Subject: [beagleboard] Re: General Purposer Timers in Linux

I want to use any one of BeagleBoard GPIO144, 145 or 146 as a timer event capture to accurately capture the Start of Frame Detect on a wireless transceiver. Does anyone have any experience on how to use OMAP3530 GPTIMERs in Linux? If someone can point me to some examples of using GPTIMERs in Linux, that would be great.

~/kernel/arch/arm/mach-omap2/timer-gp.c will be helpful,

Hi Shankar,

I’m not sure if I’m missing something, but this code looks like it will trigger an event based on an expired timer. What I’m looking for is a way to capture the value in the timer, which is triggered by an external GPIO event.

I have pointed to code for OMAP gp-timer usage. Here, you will need ISR for GPIO and free-running GP-Timer . I couldn’t find any example code as is for your use-case.