From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756674AbcJ3OfJ (ORCPT ); Sun, 30 Oct 2016 10:35:09 -0400 Received: from saturn.retrosnub.co.uk ([178.18.118.26]:42314 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753338AbcJ3OfH (ORCPT ); Sun, 30 Oct 2016 10:35:07 -0400 Subject: Re: [PATCH 04/10] iio: adc: stm32: add optional support for exti gpios To: Fabrice Gasnier , linux-iio@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <1477412722-24061-1-git-send-email-fabrice.gasnier@st.com> <1477412722-24061-5-git-send-email-fabrice.gasnier@st.com> Cc: linux@armlinux.org.uk, robh+dt@kernel.org, mark.rutland@arm.com, mcoquelin.stm32@gmail.com, alexandre.torgue@st.com, lars@metafoo.de, knaack.h@gmx.de, pmeerw@pmeerw.net From: Jonathan Cameron Message-ID: Date: Sun, 30 Oct 2016 14:35:04 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <1477412722-24061-5-git-send-email-fabrice.gasnier@st.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 25/10/16 17:25, Fabrice Gasnier wrote: > STM32 ADC may use EXTi signals routed internally as trigger source > for conversions. Configure them as interrupt to configure this path > in HW to adc. > Note: interrupt handler isn't required here, and corresponding interrupt > can be kept masked at exti controller level. > > Signed-off-by: Fabrice Gasnier > --- > drivers/iio/adc/stm32/stm32-adc.c | 45 +++++++++++++++++++++++++++++++++++++++ > drivers/iio/adc/stm32/stm32-adc.h | 3 +++ > 2 files changed, 48 insertions(+) > > diff --git a/drivers/iio/adc/stm32/stm32-adc.c b/drivers/iio/adc/stm32/stm32-adc.c > index 25d0307..1a13450 100644 > --- a/drivers/iio/adc/stm32/stm32-adc.c > +++ b/drivers/iio/adc/stm32/stm32-adc.c > @@ -482,6 +482,12 @@ static irqreturn_t stm32_adc_common_isr(int irq, void *data) > return ret; > } > > +static irqreturn_t stm32_adc_exti_handler(int irq, void *data) > +{ > + /* Exti handler should not be invoqued, and is not used */ invoked. > + return IRQ_HANDLED; > +} > + > /** > * stm32_adc_validate_trigger() - validate trigger for stm32 adc > * @indio_dev: IIO device > @@ -1051,6 +1057,41 @@ static void stm32_adc_unregister(struct stm32_adc *adc) > } > } > > +static int stm32_adc_exti_probe(struct stm32_adc_common *common) > +{ > + int i, irq, ret; > + > + common->gpios = devm_gpiod_get_array_optional(common->dev, NULL, > + GPIOD_IN); > + if (!common->gpios) > + return 0; > + > + for (i = 0; i < common->gpios->ndescs; i++) { > + irq = gpiod_to_irq(common->gpios->desc[i]); > + if (irq < 0) { > + dev_err(common->dev, "gpio %d to irq failed\n", i); > + return irq; > + } > + > + ret = devm_request_irq(common->dev, irq, stm32_adc_exti_handler, > + 0, dev_name(common->dev), common); > + if (ret) { > + dev_err(common->dev, "request IRQ %d failed\n", irq); > + return ret; > + } > + > + /* > + * gpios are configured as interrupts, so exti trigger path is > + * configured in HW. But getting interrupts when starting > + * conversions is unused here, so mask it in on exti > + * controller by default. > + */ > + disable_irq(irq); > + } > + > + return 0; > +} > + > int stm32_adc_probe(struct platform_device *pdev) > { > struct device_node *np = pdev->dev.of_node, *child; > @@ -1131,6 +1172,10 @@ int stm32_adc_probe(struct platform_device *pdev) > goto err_clk_disable; > } > > + ret = stm32_adc_exti_probe(common); > + if (ret) > + goto err_clk_disable; > + > /* Parse adc child nodes to retrieve master/slave instances data */ > for_each_available_child_of_node(np, child) { > ret = stm32_adc_register(common, child); > diff --git a/drivers/iio/adc/stm32/stm32-adc.h b/drivers/iio/adc/stm32/stm32-adc.h > index 01a0dda..fe3568b 100644 > --- a/drivers/iio/adc/stm32/stm32-adc.h > +++ b/drivers/iio/adc/stm32/stm32-adc.h > @@ -23,6 +23,7 @@ > #define __STM32_ADC_H > > #include > +#include > #include > > /* > @@ -323,6 +324,7 @@ struct stm32_adc { > * @aclk: common clock for the analog circuitry > * @vref: regulator reference > * @vref_mv: vref voltage (mv) > + * @gpio_descs: gpio descriptor used to configure EXTi triggers > * @lock: mutex > */ > struct stm32_adc_common { > @@ -335,6 +337,7 @@ struct stm32_adc_common { > struct clk *aclk; > struct regulator *vref; > int vref_mv; > + struct gpio_descs *gpios; > struct mutex lock; /* read_raw lock */ > }; > >