From: Fabrice Gasnier <fabrice.gasnier@st.com>
To: <thierry.reding@gmail.com>
Cc: <robh+dt@kernel.org>, <u.kleine-koenig@pengutronix.de>,
<tduszyns@gmail.com>, <mark.rutland@arm.com>,
<alexandre.torgue@st.com>, <mcoquelin.stm32@gmail.com>,
<fabrice.gasnier@st.com>, <devicetree@vger.kernel.org>,
<linux-arm-kernel@lists.infradead.org>,
<linux-kernel@vger.kernel.org>, <linux-pwm@vger.kernel.org>,
<linux-stm32@st-md-mailman.stormreply.com>
Subject: [RESEND PATCH v5 2/3] pwm: stm32-lp: Add power management support
Date: Thu, 18 Apr 2019 11:37:46 +0200 [thread overview]
Message-ID: <1555580267-29299-3-git-send-email-fabrice.gasnier@st.com> (raw)
In-Reply-To: <1555580267-29299-1-git-send-email-fabrice.gasnier@st.com>
Add suspend/resume PM sleep ops. When going to low power, enforce the PWM
channel isn't active. Let the PWM consumers disable it during their own
suspend sequence. Only perform a check here, and handle the pinctrl states.
See [1].
[1] https://lkml.org/lkml/2019/2/5/770
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
---
Changes in v2:
- Don't disable PWM channel: let the PWM user disable it. Refuse to
suspend in case it's been left enabled.
- Drop the ifdefs, use __maybe_unused instead.
---
drivers/pwm/pwm-stm32-lp.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)
diff --git a/drivers/pwm/pwm-stm32-lp.c b/drivers/pwm/pwm-stm32-lp.c
index 0059b24c..2211a64 100644
--- a/drivers/pwm/pwm-stm32-lp.c
+++ b/drivers/pwm/pwm-stm32-lp.c
@@ -13,6 +13,7 @@
#include <linux/mfd/stm32-lptimer.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
@@ -223,6 +224,29 @@ static int stm32_pwm_lp_remove(struct platform_device *pdev)
return pwmchip_remove(&priv->chip);
}
+static int __maybe_unused stm32_pwm_lp_suspend(struct device *dev)
+{
+ struct stm32_pwm_lp *priv = dev_get_drvdata(dev);
+ struct pwm_state state;
+
+ pwm_get_state(&priv->chip.pwms[0], &state);
+ if (state.enabled) {
+ dev_err(dev, "The consumer didn't stop us (%s)\n",
+ priv->chip.pwms[0].label);
+ return -EBUSY;
+ }
+
+ return pinctrl_pm_select_sleep_state(dev);
+}
+
+static int __maybe_unused stm32_pwm_lp_resume(struct device *dev)
+{
+ return pinctrl_pm_select_default_state(dev);
+}
+
+static SIMPLE_DEV_PM_OPS(stm32_pwm_lp_pm_ops, stm32_pwm_lp_suspend,
+ stm32_pwm_lp_resume);
+
static const struct of_device_id stm32_pwm_lp_of_match[] = {
{ .compatible = "st,stm32-pwm-lp", },
{},
@@ -235,6 +259,7 @@ static struct platform_driver stm32_pwm_lp_driver = {
.driver = {
.name = "stm32-pwm-lp",
.of_match_table = of_match_ptr(stm32_pwm_lp_of_match),
+ .pm = &stm32_pwm_lp_pm_ops,
},
};
module_platform_driver(stm32_pwm_lp_driver);
--
2.7.4
next prev parent reply other threads:[~2019-04-18 9:38 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-18 9:37 [RESEND PATCH v5 0/3] Add PM support to STM32 LP Timer drivers Fabrice Gasnier
2019-04-18 9:37 ` [RESEND PATCH v5 1/3] dt-bindings: pwm-stm32-lp: document pinctrl sleep state Fabrice Gasnier
2019-04-18 9:37 ` Fabrice Gasnier [this message]
2019-04-18 9:37 ` [RESEND PATCH v5 3/3] pwm: core: add consumer device link Fabrice Gasnier
2019-05-10 7:51 ` [RESEND PATCH v5 0/3] Add PM support to STM32 LP Timer drivers Fabrice Gasnier
2019-05-23 9:09 ` Benjamin Gaignard
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1555580267-29299-3-git-send-email-fabrice.gasnier@st.com \
--to=fabrice.gasnier@st.com \
--cc=alexandre.torgue@st.com \
--cc=devicetree@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pwm@vger.kernel.org \
--cc=linux-stm32@st-md-mailman.stormreply.com \
--cc=mark.rutland@arm.com \
--cc=mcoquelin.stm32@gmail.com \
--cc=robh+dt@kernel.org \
--cc=tduszyns@gmail.com \
--cc=thierry.reding@gmail.com \
--cc=u.kleine-koenig@pengutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).