From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756604Ab3AYMcX (ORCPT ); Fri, 25 Jan 2013 07:32:23 -0500 Received: from bear.ext.ti.com ([192.94.94.41]:45280 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755243Ab3AYMcV (ORCPT ); Fri, 25 Jan 2013 07:32:21 -0500 Message-ID: <51027B43.1080504@ti.com> Date: Fri, 25 Jan 2013 13:32:03 +0100 From: Peter Ujfalusi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130115 Thunderbird/17.0.2 MIME-Version: 1.0 To: Florian Vaussard CC: Bryan Wu , Richard Purdie , Thierry Reding , , , Subject: Re: [PATCH 1/3] pwm: Add pwm_cansleep() as exported API to users References: <1359108114-16998-1-git-send-email-florian.vaussard@epfl.ch> <1359108114-16998-2-git-send-email-florian.vaussard@epfl.ch> In-Reply-To: <1359108114-16998-2-git-send-email-florian.vaussard@epfl.ch> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/25/2013 11:01 AM, Florian Vaussard wrote: > Calls to some external PWM chips can sleep. To help users, > add pwm_cansleep() API. > > Signed-off-by: Florian Vaussard > --- > drivers/pwm/core.c | 12 ++++++++++++ > include/linux/pwm.h | 10 ++++++++++ > 2 files changed, 22 insertions(+), 0 deletions(-) > > diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c > index 4a13da4..f49bfa6 100644 > --- a/drivers/pwm/core.c > +++ b/drivers/pwm/core.c > @@ -763,6 +763,18 @@ void devm_pwm_put(struct device *dev, struct pwm_device *pwm) > } > EXPORT_SYMBOL_GPL(devm_pwm_put); > > +/** > + * pwm_can_sleep() - report whether pwm access will sleep > + * @pwm: PWM device > + * > + * It returns nonzero if accessing the PWM can sleep. > + */ > +int pwm_can_sleep(struct pwm_device *pwm) > +{ > + return pwm->chip->can_sleep; > +} > +EXPORT_SYMBOL_GPL(pwm_can_sleep); Can we name this as pwm_cansleep() to be more alligned with the gpio_cansleep() API? > + > #ifdef CONFIG_DEBUG_FS > static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s) > { > diff --git a/include/linux/pwm.h b/include/linux/pwm.h > index 70655a2..2aee75d 100644 > --- a/include/linux/pwm.h > +++ b/include/linux/pwm.h > @@ -146,6 +146,8 @@ struct pwm_ops { > * @base: number of first PWM controlled by this chip > * @npwm: number of PWMs controlled by this chip > * @pwms: array of PWM devices allocated by the framework > + * @can_sleep: flag must be set iff config()/enable()/disable() methods sleep, > + * as they must while accessing PWM chips over I2C or SPI > */ > struct pwm_chip { > struct device *dev; > @@ -159,6 +161,7 @@ struct pwm_chip { > struct pwm_device * (*of_xlate)(struct pwm_chip *pc, > const struct of_phandle_args *args); > unsigned int of_pwm_n_cells; > + unsigned int can_sleep:1; > }; > > #if IS_ENABLED(CONFIG_PWM) > @@ -182,6 +185,8 @@ struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id); > struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, > const char *con_id); > void devm_pwm_put(struct device *dev, struct pwm_device *pwm); > + > +int pwm_can_sleep(struct pwm_device *pwm); > #else > static inline int pwm_set_chip_data(struct pwm_device *pwm, void *data) > { > @@ -242,6 +247,11 @@ static inline struct pwm_device *devm_of_pwm_get(struct device *dev, > static inline void devm_pwm_put(struct device *dev, struct pwm_device *pwm) > { > } > + > +static inline int pwm_can_sleep(struct pwm_device *pwm) > +{ > + return -EINVAL; I think we should return 0 here instead an error. > +} > #endif > > struct pwm_lookup { > -- Péter