From mboxrd@z Thu Jan 1 00:00:00 1970 From: santosh.shilimkar@ti.com (Santosh Shilimkar) Date: Fri, 26 Oct 2012 11:31:34 +0530 Subject: [PATCH v3] gpio/omap: fix off-mode bug: clear debounce clock enable mask on free/reset In-Reply-To: <5089C2B6.5020606@ti.com> References: <1351182858-14045-1-git-send-email-khilman@deeprootsystems.com> <5089C2B6.5020606@ti.com> Message-ID: <508A273E.3020500@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Jon, On Friday 26 October 2012 04:22 AM, Jon Hunter wrote: > Hi Kevin, > > On 10/25/2012 11:34 AM, Kevin Hilman wrote: >> From: Kevin Hilman >> [...] >> diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c >> index 94cbc84..ce1da19 100644 >> --- a/drivers/gpio/gpio-omap.c >> +++ b/drivers/gpio/gpio-omap.c >> @@ -539,6 +539,8 @@ static void _reset_gpio(struct gpio_bank *bank, int gpio) >> _set_gpio_irqenable(bank, gpio, 0); >> _clear_gpio_irqstatus(bank, gpio); >> _set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), IRQ_TYPE_NONE); >> + bank->dbck_enable_mask &= ~(GPIO_BIT(bank, gpio)); >> + _gpio_dbck_disable(bank); > > We can't use _gpio_dbck_disable() here. This has been specifically implemented > for the suspend path and is designed to disable the debounce clock while > debounce is enabled (which makes sense). Yes this needs to be cleaned up. > I thought this bit was clear on v2 discussion list that debounce clock disable needs to be conditional based on debounce mask. > From 33812f3bd4f7aab1154e7194b7f11fba700a5086 Mon Sep 17 00:00:00 2001 > From: Jon Hunter > Date: Thu, 25 Oct 2012 16:00:51 -0500 > Subject: [PATCH] gpio/omap: fix clearing of debounce settings on gpio > free/reset > > When a GPIO is freed or shutdown, we need to ensure that any debounce settings > are cleared and if the GPIO is the only GPIO in the bank that is currently > using debounce, then disable the debounce clock as well to save power. > > Therefore, introduce a new function called _clear_gpio_debounce() to clear > any debounce settings when the GPIO is freed or shutdown. > > Please note that we cannot use _gpio_dbck_disable() to disable the debounce > clock because this has been specifically created for the gpio suspend path > and is intended to shutdown the debounce clock while debounce is enabled. > > This has been unit tested on an OMAP3430 Beagle board, by requesting a gpio, > enabling debounce and then freeing the gpio and checking the register contents, > the saved register context and the debounce clock state. > > Signed-off-by: Jon Hunter > --- Now that we are aligned, so we can take this patch forward. Feel free to add my ack in case you plan to refresh it. Acked-by: Santosh Shilimkar