Re: Panda ES board hang when using GPIO as interrupt
From: Franky Lin <hidden>
Date: 2012-06-28 22:53:27
Also in:
linux-arm-kernel, linux-omap
Possibly related (same subject, not in this thread)
- 2012-06-28 · Panda ES board hang when using GPIO as interrupt · Jon Hunter <hidden>
- 2012-06-28 · Panda ES board hang when using GPIO as interrupt · Franky Lin <hidden>
- 2012-06-27 · Panda ES board hang when using GPIO as interrupt · Jon Hunter <hidden>
- 2012-06-27 · Panda ES board hang when using GPIO as interrupt · DebBarma, Tarun Kanti <hidden>
- 2012-06-26 · Panda ES board hang when using GPIO as interrupt · Franky Lin <hidden>
On 06/28/2012 02:55 PM, Jon Hunter wrote:
Ok. Any way to manually reset the wlan module to deactivate the gpio when it is hung? I am wondering if the gpio is deactivated if the board comes back to life, indicating it is stuck in the interrupt somewhere.
The only way I can think of is removing the module manually. But it didn't bring the board back to live.
quoted hunk ↗ jump to hunk
Well, at least that is consistent with what I see, but also perplexing that it takes sometime to fail. Can you try the following as a debug patch to see if it is in the context restore that is the problem. From your testing and bisect, the only possible difference in the current kernel is that it could perform the context restore when acquiring the gpio.diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c index c4ed172..a2401bd 100644 --- a/drivers/gpio/gpio-omap.c +++ b/drivers/gpio/gpio-omap.c@@ -1341,6 +1341,8 @@ void omap2_gpio_resume_after_idle(void) #if defined(CONFIG_PM_RUNTIME) static void omap_gpio_restore_context(struct gpio_bank *bank) { + return; + __raw_writel(bank->context.wake_en, bank->base + bank->regs->wkup_en); __raw_writel(bank->context.ctrl, bank->base + bank->regs->ctrl);
This one works! It can run more than 20 mins. I found one interesting thing. When I added the print info to see when runtime_suspend/resume get called, it seems like the suspend/resume is unbalance during boot. Resume got called more than suspend. So I hack the code to make sure suspend and resume are called in pair. A resume without suspend will do nothing and return immediately. This also makes the hang vanish. Regards, Franky