On Tue, Oct 23, 2012 at 9:09 PM, Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx> wrote: > From: Kevin Hilman <khilman@xxxxxx> > > When debounce clocks are disabled, ensure that the banks > dbck_enable_mask is cleared also. Otherwise, context restore on > subsequent off-mode transition will restore previous value from the > shadow copies (bank->context.debounce*) leading to mismatch state > between driver state and hardware state. This doesn't look right to me, aren't you effectively disabling debounce forever here? _gpio_dbck_disable is called from omap_gpio_runtime_suspend() and nothing will ever restore dbck_enable_mask back to what it was set by _set_gpio_debounce and debounce functionality is lost. > > This was discovered when board code was doing > > gpio_request_one() > gpio_set_debounce() > gpio_free() > > which was leaving the GPIO debounce settings in a confused state. > Then, enabling off mode causing bogus state to be restored, leaving > GPIO debounce enabled which then prevented the CORE powerdomain from > transitioning. > > Reported-by: Paul Walmsley <paul@xxxxxxxxx> > Cc: Igor Grinberg <grinberg@xxxxxxxxxxxxxx> > Signed-off-by: Kevin Hilman <khilman@xxxxxx> > --- > Applies on v3.7-rc2, targetted for v3.7. > > drivers/gpio/gpio-omap.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c > index 94cbc84..dee2856 100644 > --- a/drivers/gpio/gpio-omap.c > +++ b/drivers/gpio/gpio-omap.c > @@ -187,6 +187,7 @@ static inline void _gpio_dbck_disable(struct gpio_bank *bank) > * to detect events and generate interrupts at least on OMAP3. > */ > __raw_writel(0, bank->base + bank->regs->debounce_en); > + bank->dbck_enable_mask = 0; > > clk_disable(bank->dbck); > bank->dbck_enabled = false; > -- > 1.8.0 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- Gražvydas -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
