Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753696AbdCORG0 convert rfc822-to-8bit (ORCPT ); Wed, 15 Mar 2017 13:06:26 -0400 Received: from gloria.sntech.de ([95.129.55.99]:50314 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751866AbdCOREq (ORCPT ); Wed, 15 Mar 2017 13:04:46 -0400 From: Heiko Stuebner To: John Keeping Cc: Linus Walleij , linux-gpio@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 4/4] pinctrl: rockchip: avoid hardirq-unsafe functions in irq_chip Date: Wed, 15 Mar 2017 18:04:37 +0100 Message-ID: <8279144.RSoYI8sFdD@phil> User-Agent: KMail/5.2.3 (Linux/4.9.0-1-amd64; KDE/5.27.0; x86_64; ; ) In-Reply-To: <20170313183813.3582-5-john@metanate.com> References: <20170313183813.3582-1-john@metanate.com> <20170313183813.3582-5-john@metanate.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4129 Lines: 128 Am Montag, 13. M?rz 2017, 18:38:13 CET schrieb John Keeping: > With real-time preemption, regmap functions cannot be used in the > implementation of irq_chip since they use spinlocks which may sleep. > > Move the setting of the mux for IRQs to an irq_bus_sync_unlock handler > where we are allowed to sleep. > > Signed-off-by: John Keeping Looks good Reviewed-by: Heiko Stuebner > --- > drivers/pinctrl/pinctrl-rockchip.c | 44 > ++++++++++++++++++++++++++++++++++---- 1 file changed, 40 insertions(+), 4 > deletions(-) > > diff --git a/drivers/pinctrl/pinctrl-rockchip.c > b/drivers/pinctrl/pinctrl-rockchip.c index 52e70c4aef7c..80f7c23d12d4 > 100644 > --- a/drivers/pinctrl/pinctrl-rockchip.c > +++ b/drivers/pinctrl/pinctrl-rockchip.c > @@ -143,6 +143,9 @@ struct rockchip_drv { > * @gpio_chip: gpiolib chip > * @grange: gpio range > * @slock: spinlock for the gpio bank > + * @irq_lock: bus lock for irq chip > + * @new_irqs: newly configured irqs which must be muxed as GPIOs in > + * irq_bus_sync_unlock() > */ > struct rockchip_pin_bank { > void __iomem *reg_base; > @@ -165,6 +168,8 @@ struct rockchip_pin_bank { > struct pinctrl_gpio_range grange; > raw_spinlock_t slock; > u32 toggle_edge_mode; > + struct mutex irq_lock; > + u32 new_irqs; > }; > > #define PIN_BANK(id, pins, label) \ > @@ -2045,11 +2050,12 @@ static int rockchip_irq_set_type(struct irq_data *d, > unsigned int type) int ret; > > /* make sure the pin is configured as gpio input */ > - ret = rockchip_set_mux(bank, d->hwirq, RK_FUNC_GPIO); > + ret = rockchip_verify_mux(bank, d->hwirq, RK_FUNC_GPIO); > if (ret < 0) > return ret; > > - clk_enable(bank->clk); > + bank->new_irqs |= mask; > + > raw_spin_lock_irqsave(&bank->slock, flags); > > data = readl_relaxed(bank->reg_base + GPIO_SWPORT_DDR); > @@ -2107,7 +2113,6 @@ static int rockchip_irq_set_type(struct irq_data *d, > unsigned int type) default: > irq_gc_unlock(gc); > raw_spin_unlock_irqrestore(&bank->slock, flags); > - clk_disable(bank->clk); > return -EINVAL; > } > > @@ -2116,7 +2121,6 @@ static int rockchip_irq_set_type(struct irq_data *d, > unsigned int type) > > irq_gc_unlock(gc); > raw_spin_unlock_irqrestore(&bank->slock, flags); > - clk_disable(bank->clk); > > return 0; > } > @@ -2160,6 +2164,34 @@ static void rockchip_irq_gc_mask_set_bit(struct > irq_data *d) clk_disable(bank->clk); > } > > +static void rockchip_irq_bus_lock(struct irq_data *d) > +{ > + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); > + struct rockchip_pin_bank *bank = gc->private; > + > + clk_enable(bank->clk); > + mutex_lock(&bank->irq_lock); > +} > + > +static void rockchip_irq_bus_sync_unlock(struct irq_data *d) > +{ > + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); > + struct rockchip_pin_bank *bank = gc->private; > + > + while (bank->new_irqs) { > + unsigned int irq = __ffs(bank->new_irqs); > + int ret; > + > + ret = rockchip_set_mux(bank, irq, RK_FUNC_GPIO); > + WARN_ON(ret < 0); > + > + bank->new_irqs &= ~BIT(irq); > + } > + > + mutex_unlock(&bank->irq_lock); > + clk_disable(bank->clk); > +} > + > static int rockchip_interrupts_register(struct platform_device *pdev, > struct rockchip_pinctrl *info) > { > @@ -2225,6 +2257,9 @@ static int rockchip_interrupts_register(struct > platform_device *pdev, gc->chip_types[0].chip.irq_suspend = > rockchip_irq_suspend; > gc->chip_types[0].chip.irq_resume = rockchip_irq_resume; > gc->chip_types[0].chip.irq_set_type = rockchip_irq_set_type; > + gc->chip_types[0].chip.irq_bus_lock = rockchip_irq_bus_lock; > + gc->chip_types[0].chip.irq_bus_sync_unlock = > + rockchip_irq_bus_sync_unlock; > gc->wake_enabled = IRQ_MSK(bank->nr_pins); > > irq_set_chained_handler_and_data(bank->irq, > @@ -2398,6 +2433,7 @@ static struct rockchip_pin_ctrl > *rockchip_pinctrl_get_soc_data( int bank_pins = 0; > > raw_spin_lock_init(&bank->slock); > + mutex_init(&bank->irq_lock); > bank->drvdata = d; > bank->pin_base = ctrl->nr_pins; > ctrl->nr_pins += bank->nr_pins;