From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752968AbcDVKVG (ORCPT ); Fri, 22 Apr 2016 06:21:06 -0400 Received: from mail-wm0-f48.google.com ([74.125.82.48]:35685 "EHLO mail-wm0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752241AbcDVKSW (ORCPT ); Fri, 22 Apr 2016 06:18:22 -0400 From: Lee Jones To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: kernel@stlinux.com, maxime.coquelin@st.com, linux-pwm@vger.kernel.org, thierry.reding@gmail.com, ajitpal.singh@st.com, Lee Jones Subject: [[PATCH v2] 01/11] pwm: Add PWM Capture support Date: Fri, 22 Apr 2016 11:18:05 +0100 Message-Id: <1461320295-20414-2-git-send-email-lee.jones@linaro.org> X-Mailer: git-send-email 2.8.0 In-Reply-To: <1461320295-20414-1-git-send-email-lee.jones@linaro.org> References: <1461320295-20414-1-git-send-email-lee.jones@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Supply a PWM Capture call-back Op in order to pass back information obtained by running analysis on PWM a signal. This would normally (at least during testing) be called from the Sysfs routines with a view to printing out PWM Capture data which has been encoded into a string. Signed-off-by: Lee Jones --- drivers/pwm/core.c | 27 +++++++++++++++++++++++++++ include/linux/pwm.h | 28 ++++++++++++++++++++++++++++ 2 files changed, 55 insertions(+) diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 7831bc6..160784d 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -494,6 +494,33 @@ unlock: EXPORT_SYMBOL_GPL(pwm_set_polarity); /** + * pwm_capture() - capture and report a PWM signal + * @pwm: PWM device + * @result: struct to fill with capture result + * @timeout_ms: time to wait, in milliseconds, before giving up on capture + * + * Returns: 0 on success or a negative error code on failure. + */ +int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result, + unsigned int timeout_ms) +{ + int err; + + if (!pwm || !pwm->chip->ops) + return -EINVAL; + + if (!pwm->chip->ops->capture) + return -ENOSYS; + + mutex_lock(&pwm->lock); + err = pwm->chip->ops->capture(pwm->chip, pwm, result, timeout_ms); + mutex_unlock(&pwm->lock); + + return err; +} +EXPORT_SYMBOL_GPL(pwm_capture); + +/** * pwm_enable() - start a PWM output toggling * @pwm: PWM device * diff --git a/include/linux/pwm.h b/include/linux/pwm.h index cfc3ed4..49f9648 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -6,6 +6,7 @@ #include struct pwm_device; +struct pwm_capture; struct seq_file; #if IS_ENABLED(CONFIG_PWM) @@ -33,6 +34,13 @@ int pwm_enable(struct pwm_device *pwm); * pwm_disable - stop a PWM output toggling */ void pwm_disable(struct pwm_device *pwm); + +/* + * pwm_capture - capture and report a PWM signal + */ +int pwm_capture(struct pwm_device *pwm, + struct pwm_capture *result, + unsigned int timeout_ms); #else static inline struct pwm_device *pwm_request(int pwm_id, const char *label) { @@ -56,6 +64,13 @@ static inline int pwm_enable(struct pwm_device *pwm) static inline void pwm_disable(struct pwm_device *pwm) { } + +static inline int pwm_capture(struct pwm_device *pwm, + struct pwm_capture *result, + unsigned int timeout_ms) +{ + return -EINVAL; +} #endif struct pwm_chip; @@ -107,6 +122,16 @@ struct pwm_device { enum pwm_polarity polarity; }; +/** + * struct pwm_capture - PWM capture data + * @period: period of the PWM signal (in nanoseconds) + * @duty_cycle: duty cycle of the PWM signal (in nanoseconds) + */ +struct pwm_capture { + unsigned long long period; + unsigned long long duty_cycle; +}; + static inline bool pwm_is_enabled(const struct pwm_device *pwm) { return test_bit(PWMF_ENABLED, &pwm->flags); @@ -150,6 +175,7 @@ static inline enum pwm_polarity pwm_get_polarity(const struct pwm_device *pwm) * @free: optional hook for freeing a PWM * @config: configure duty cycles and period length for this PWM * @set_polarity: configure the polarity of this PWM + * @capture: capture and report PWM signal * @enable: enable PWM output toggling * @disable: disable PWM output toggling * @dbg_show: optional routine to show contents in debugfs @@ -162,6 +188,8 @@ struct pwm_ops { int duty_ns, int period_ns); int (*set_polarity)(struct pwm_chip *chip, struct pwm_device *pwm, enum pwm_polarity polarity); + int (*capture)(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_capture *result, unsigned int timeout_ms); int (*enable)(struct pwm_chip *chip, struct pwm_device *pwm); void (*disable)(struct pwm_chip *chip, struct pwm_device *pwm); #ifdef CONFIG_DEBUG_FS -- 2.8.0