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: Thu, 19 Mar 2015 16:03:27 -0700 Message-ID: <20150319230326.GP31346@atomide.com> References: <1425670017-19598-1-git-send-email-grygorii.strashko@linaro.org> <1425670017-19598-2-git-send-email-grygorii.strashko@linaro.org> <20150306231513.GB2651@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20150306231513.GB2651@atomide.com> Sender: linux-omap-owner@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 List-Id: linux-gpio@vger.kernel.org * Tony Lindgren [150307 00:08]: > * 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()"). OK so I finally got around testing this along with your bank removal set. Looks like this patch causes a regression at least with n900 keyboard LEDs with off-idle. The LED won't come back on after restore from off-idle. Anyways, now we have something reproducable :) So I'll try to debug it further at some point, might be few days before I get to it. 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 > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html