From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [RFC/RFT PATCH 2/2] gpio: omap: ensure that runtime pm will disable unused gpio banks Date: Fri, 6 Mar 2015 15:15:30 -0800 Message-ID: <20150306231513.GB2651@atomide.com> References: <1425670017-19598-1-git-send-email-grygorii.strashko@linaro.org> <1425670017-19598-2-git-send-email-grygorii.strashko@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from muru.com ([72.249.23.125]:35382 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754411AbbCFXUu (ORCPT ); Fri, 6 Mar 2015 18:20:50 -0500 Content-Disposition: inline In-Reply-To: <1425670017-19598-2-git-send-email-grygorii.strashko@linaro.org> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: grygorii.strashko@linaro.org Cc: Linus Walleij , ssantosh@kernel.org, Javier Martinez Canillas , Alexandre Courbot , linux-omap@vger.kernel.org, linux-gpio@vger.kernel.org * grygorii.strashko@linaro.org [150306 11:27]: > From: Grygorii Strashko > > Now there are two points related to Runtime PM usage: > 1) bank state doesn't need to be checked in places where > Rintime PM is used, bacause Runtime PM maintains its > own usage counter: > if (!BANK_USED(bank)) > pm_runtime_get_sync(bank->dev); > so, it's safe to drop such checks. > > 2) There is a call of pm_runtime_get_sync() in omap_gpio_irq_type(), > but no corresponding put. As result, GPIO devices could be > powered on forever if at least one GPIO was used as IRQ. > Hence, allow powering off GPIO banks by adding missed > pm_runtime_put(bank->dev) at the end of omap_gpio_irq_type(). Nice to see this happening, but I think before merging this we need to test to be sure that the pm_runtime calls actually match.. I'm not convinced right now.. We may still have uninitialized entry points similar to 3d009c8c61f9 ("gpio: omap: Fix bad device access with setup_irq()"). Regards, Tony > Signed-off-by: Grygorii Strashko > --- > drivers/gpio/gpio-omap.c | 17 +++++++---------- > 1 file changed, 7 insertions(+), 10 deletions(-) > > diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c > index 2b2fc4b..b1176c5 100644 > --- a/drivers/gpio/gpio-omap.c > +++ b/drivers/gpio/gpio-omap.c > @@ -497,8 +497,7 @@ static int omap_gpio_irq_type(struct irq_data *d, unsigned type) > unsigned long flags; > unsigned offset; > > - if (!BANK_USED(bank)) > - pm_runtime_get_sync(bank->dev); > + pm_runtime_get_sync(bank->dev); > > #ifdef CONFIG_ARCH_OMAP1 > if (d->irq > IH_MPUIO_BASE) > @@ -530,6 +529,8 @@ static int omap_gpio_irq_type(struct irq_data *d, unsigned type) > else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)) > __irq_set_handler_locked(d->irq, handle_edge_irq); > > + pm_runtime_put(bank->dev); > + > return retval; > } > > @@ -680,8 +681,7 @@ static int omap_gpio_request(struct gpio_chip *chip, unsigned offset) > * If this is the first gpio_request for the bank, > * enable the bank module. > */ > - if (!BANK_USED(bank)) > - pm_runtime_get_sync(bank->dev); > + pm_runtime_get_sync(bank->dev); > > spin_lock_irqsave(&bank->lock, flags); > /* Set trigger to none. You need to enable the desired trigger with > @@ -713,8 +713,7 @@ static void omap_gpio_free(struct gpio_chip *chip, unsigned offset) > * If this is the last gpio to be freed in the bank, > * disable the bank module. > */ > - if (!BANK_USED(bank)) > - pm_runtime_put(bank->dev); > + pm_runtime_put(bank->dev); > } > > /* > @@ -807,8 +806,7 @@ static unsigned int omap_gpio_irq_startup(struct irq_data *d) > unsigned long flags; > unsigned offset = GPIO_INDEX(bank, gpio); > > - if (!BANK_USED(bank)) > - pm_runtime_get_sync(bank->dev); > + pm_runtime_get_sync(bank->dev); > > spin_lock_irqsave(&bank->lock, flags); > omap_gpio_init_irq(bank, gpio, offset); > @@ -835,8 +833,7 @@ static void omap_gpio_irq_shutdown(struct irq_data *d) > * If this is the last IRQ to be freed in the bank, > * disable the bank module. > */ > - if (!BANK_USED(bank)) > - pm_runtime_put(bank->dev); > + pm_runtime_put(bank->dev); > } > > static void omap_gpio_ack_irq(struct irq_data *d) > -- > 1.9.1 >