[PATCH for-5.4.y 0/3] db845c(sdm845) PM runtime fixes

[PATCH for-5.4.y 0/3] db845c(sdm845) PM runtime fixes

[Amit Pundir]

Hi,

v5.4.y commit 31b169a8bed7 ("drm/msm/dsi: Use pm_runtime_resume_and_get
to prevent refcnt leaks"), which is commit 3d07a411b4fa upstream, broke
display on Dragonboard 845c(sdm845). Cherry-picking commit 6ab502bc1cf3
("drm/msm/dsi: Enable runtime PM") from the original patch series
https://patchwork.freedesktop.org/series/119583/
and it's dependent runtime PM helper routines as suggested by Dmitry
https://lore.kernel.org/stable/CAA8EJpo7q9qZbgXHWe7SuQFh0EWW0ZxGL5xYX4nckoFGoGAtPw@mail.gmail.com
fixes that display regression on DB845c.

Dmitry Baryshkov (1):
  PM: runtime: add devm_pm_runtime_enable helper

Douglas Anderson (1):
  PM: runtime: Have devm_pm_runtime_enable() handle
    pm_runtime_dont_use_autosuspend()

Konrad Dybcio (1):
  drm/msm/dsi: Enable runtime PM

 drivers/base/power/runtime.c          | 22 ++++++++++++++++++++++
 drivers/gpu/drm/msm/dsi/phy/dsi_phy.c |  4 ++++
 include/linux/pm_runtime.h            |  9 +++++++++
 3 files changed, 35 insertions(+)

-- 
2.25.1

[PATCH for-v5.4.y 1/3] PM: runtime: add devm_pm_runtime_enable helper

[Amit Pundir]

From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

[ Upstream commit b3636a3a2c51715736d3ec45f635ed03191962ce ]

A typical code pattern for pm_runtime_enable() call is to call it in the
_probe function and to call pm_runtime_disable() both from _probe error
path and from _remove function. For some drivers the whole remove
function would consist of the call to pm_remove_disable().

Add helper function to replace this bolierplate piece of code. Calling
devm_pm_runtime_enable() removes the need for calling
pm_runtime_disable() both in the probe()'s error path and in the
remove() function.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20210731195034.979084-2-dmitry.baryshkov@linaro.org
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Stable-dep-of: 3d07a411b4fa ("drm/msm/dsi: Use pm_runtime_resume_and_get to prevent refcnt leaks")
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
---
 drivers/base/power/runtime.c | 17 +++++++++++++++++
 include/linux/pm_runtime.h   |  4 ++++
 2 files changed, 21 insertions(+)

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 626f22c01f2f..f31609f3e7fa 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -1475,6 +1475,23 @@ void pm_runtime_enable(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(pm_runtime_enable);
 
+static void pm_runtime_disable_action(void *data)
+{
+	pm_runtime_disable(data);
+}
+
+/**
+ * devm_pm_runtime_enable - devres-enabled version of pm_runtime_enable.
+ * @dev: Device to handle.
+ */
+int devm_pm_runtime_enable(struct device *dev)
+{
+	pm_runtime_enable(dev);
+
+	return devm_add_action_or_reset(dev, pm_runtime_disable_action, dev);
+}
+EXPORT_SYMBOL_GPL(devm_pm_runtime_enable);
+
 /**
  * pm_runtime_forbid - Block runtime PM of a device.
  * @dev: Device to handle.
diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
index c7c754884cdc..eda6619a6358 100644
--- a/include/linux/pm_runtime.h
+++ b/include/linux/pm_runtime.h
@@ -60,6 +60,8 @@ extern void pm_runtime_put_suppliers(struct device *dev);
 extern void pm_runtime_new_link(struct device *dev);
 extern void pm_runtime_drop_link(struct device_link *link);
 
+extern int devm_pm_runtime_enable(struct device *dev);
+
 static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
 {
 	dev->power.ignore_children = enable;
@@ -156,6 +158,8 @@ static inline void __pm_runtime_disable(struct device *dev, bool c) {}
 static inline void pm_runtime_allow(struct device *dev) {}
 static inline void pm_runtime_forbid(struct device *dev) {}
 
+static inline int devm_pm_runtime_enable(struct device *dev) { return 0; }
+
 static inline void pm_suspend_ignore_children(struct device *dev, bool enable) {}
 static inline void pm_runtime_get_noresume(struct device *dev) {}
 static inline void pm_runtime_put_noidle(struct device *dev) {}
-- 
2.25.1

[PATCH for-v5.4.y 2/3] PM: runtime: Have devm_pm_runtime_enable() handle pm_runtime_dont_use_autosuspend()

[Amit Pundir]

From: Douglas Anderson <dianders@chromium.org>

[ Upstream commit b4060db9251f919506e4d672737c6b8ab9a84701 ]

The PM Runtime docs say:

  Drivers in ->remove() callback should undo the runtime PM changes done
  in ->probe(). Usually this means calling pm_runtime_disable(),
  pm_runtime_dont_use_autosuspend() etc.

From grepping code, it's clear that many people aren't aware of the
need to call pm_runtime_dont_use_autosuspend().

When brainstorming solutions, one idea that came up was to leverage
the new-ish devm_pm_runtime_enable() function. The idea here is that:

 * When the devm action is called we know that the driver is being
   removed. It's the perfect time to undo the use_autosuspend.

 * The code of pm_runtime_dont_use_autosuspend() already handles the
   case of being called when autosuspend wasn't enabled.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: 3d07a411b4fa ("drm/msm/dsi: Use pm_runtime_resume_and_get to prevent refcnt leaks")
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
---
 drivers/base/power/runtime.c | 5 +++++
 include/linux/pm_runtime.h   | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index f31609f3e7fa..a10121b05aaf 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -1477,11 +1477,16 @@ EXPORT_SYMBOL_GPL(pm_runtime_enable);
 
 static void pm_runtime_disable_action(void *data)
 {
+	pm_runtime_dont_use_autosuspend(data);
 	pm_runtime_disable(data);
 }
 
 /**
  * devm_pm_runtime_enable - devres-enabled version of pm_runtime_enable.
+ *
+ * NOTE: this will also handle calling pm_runtime_dont_use_autosuspend() for
+ * you at driver exit time if needed.
+ *
  * @dev: Device to handle.
  */
 int devm_pm_runtime_enable(struct device *dev)
diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
index eda6619a6358..ea0dd2c81e7f 100644
--- a/include/linux/pm_runtime.h
+++ b/include/linux/pm_runtime.h
@@ -296,6 +296,11 @@ static inline void pm_runtime_disable(struct device *dev)
 	__pm_runtime_disable(dev, true);
 }
 
+/**
+ * NOTE: It's important to undo this with pm_runtime_dont_use_autosuspend()
+ * at driver exit time unless your driver initially enabled pm_runtime
+ * with devm_pm_runtime_enable() (which handles it for you).
+ */
 static inline void pm_runtime_use_autosuspend(struct device *dev)
 {
 	__pm_runtime_use_autosuspend(dev, true);
-- 
2.25.1

[PATCH for-v5.4.y 3/3] drm/msm/dsi: Enable runtime PM

[Amit Pundir]

From: Konrad Dybcio <konrad.dybcio@linaro.org>

[ Upstream commit 6ab502bc1cf3147ea1d8540d04b83a7a4cb6d1f1 ]

Some devices power the DSI PHY/PLL through a power rail that we model
as a GENPD. Enable runtime PM to make it suspendable.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/543352/
Link: https://lore.kernel.org/r/20230620-topic-dsiphy_rpm-v2-2-a11a751f34f0@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Stable-dep-of: 3d07a411b4fa ("drm/msm/dsi: Use pm_runtime_resume_and_get to prevent refcnt leaks")
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
---
 drivers/gpu/drm/msm/dsi/phy/dsi_phy.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c
index 1582386fe162..925262ea6f14 100644
--- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c
+++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c
@@ -606,6 +606,10 @@ static int dsi_phy_driver_probe(struct platform_device *pdev)
 			goto fail;
 	}
 
+	ret = devm_pm_runtime_enable(&pdev->dev);
+	if (ret)
+		return ret;
+
 	/* PLL init will call into clk_register which requires
 	 * register access, so we need to enable power and ahb clock.
 	 */
-- 
2.25.1

Re: [PATCH for-5.4.y 0/3] db845c(sdm845) PM runtime fixes

[Greg KH]

On Mon, Jan 29, 2024 at 04:08:59PM +0530, Amit Pundir wrote:
> Hi,
> 
> v5.4.y commit 31b169a8bed7 ("drm/msm/dsi: Use pm_runtime_resume_and_get
> to prevent refcnt leaks"), which is commit 3d07a411b4fa upstream, broke
> display on Dragonboard 845c(sdm845). Cherry-picking commit 6ab502bc1cf3
> ("drm/msm/dsi: Enable runtime PM") from the original patch series
> https://patchwork.freedesktop.org/series/119583/
> and it's dependent runtime PM helper routines as suggested by Dmitry
> https://lore.kernel.org/stable/CAA8EJpo7q9qZbgXHWe7SuQFh0EWW0ZxGL5xYX4nckoFGoGAtPw@mail.gmail.com
> fixes that display regression on DB845c.

We need fixes for all of the newer stable trees too, you can't fix an
issue in an old tree and then if you upgraded, you would run into that
issue again.

So please, resend this series as a set of series for all active lts
kernels, and we will be glad to queue them up.

thanks,

greg k-h

Re: [PATCH for-5.4.y 0/3] db845c(sdm845) PM runtime fixes

[Amit Pundir]

On Mon, 29 Jan 2024 at 21:51, Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Mon, Jan 29, 2024 at 04:08:59PM +0530, Amit Pundir wrote:
> > Hi,
> >
> > v5.4.y commit 31b169a8bed7 ("drm/msm/dsi: Use pm_runtime_resume_and_get
> > to prevent refcnt leaks"), which is commit 3d07a411b4fa upstream, broke
> > display on Dragonboard 845c(sdm845). Cherry-picking commit 6ab502bc1cf3
> > ("drm/msm/dsi: Enable runtime PM") from the original patch series
> > https://patchwork.freedesktop.org/series/119583/
> > and it's dependent runtime PM helper routines as suggested by Dmitry
> > https://lore.kernel.org/stable/CAA8EJpo7q9qZbgXHWe7SuQFh0EWW0ZxGL5xYX4nckoFGoGAtPw@mail.gmail.com
> > fixes that display regression on DB845c.
>
> We need fixes for all of the newer stable trees too, you can't fix an
> issue in an old tree and then if you upgraded, you would run into that
> issue again.
>
> So please, resend this series as a set of series for all active lts
> kernels, and we will be glad to queue them up.

Ack. I'll send the patch series for all the active LTS kernels
tomorrow after build/boot testing them locally. Meanwhile please
consider this patch series for v5.4.y anyway.

Regards,
Amit Pundir

>
> thanks,
>
> greg k-h

Re: [PATCH for-5.4.y 0/3] db845c(sdm845) PM runtime fixes

[Greg KH]

On Mon, Jan 29, 2024 at 10:59:53PM +0530, Amit Pundir wrote:
> On Mon, 29 Jan 2024 at 21:51, Greg KH <gregkh@linuxfoundation.org> wrote:
> >
> > On Mon, Jan 29, 2024 at 04:08:59PM +0530, Amit Pundir wrote:
> > > Hi,
> > >
> > > v5.4.y commit 31b169a8bed7 ("drm/msm/dsi: Use pm_runtime_resume_and_get
> > > to prevent refcnt leaks"), which is commit 3d07a411b4fa upstream, broke
> > > display on Dragonboard 845c(sdm845). Cherry-picking commit 6ab502bc1cf3
> > > ("drm/msm/dsi: Enable runtime PM") from the original patch series
> > > https://patchwork.freedesktop.org/series/119583/
> > > and it's dependent runtime PM helper routines as suggested by Dmitry
> > > https://lore.kernel.org/stable/CAA8EJpo7q9qZbgXHWe7SuQFh0EWW0ZxGL5xYX4nckoFGoGAtPw@mail.gmail.com
> > > fixes that display regression on DB845c.
> >
> > We need fixes for all of the newer stable trees too, you can't fix an
> > issue in an old tree and then if you upgraded, you would run into that
> > issue again.
> >
> > So please, resend this series as a set of series for all active lts
> > kernels, and we will be glad to queue them up.
> 
> Ack. I'll send the patch series for all the active LTS kernels
> tomorrow after build/boot testing them locally. Meanwhile please
> consider this patch series for v5.4.y anyway.

Nope, I have to wait until the newer changes show up, for obvious
reasonse.

thanks,

greg k-h

Re: [PATCH for-5.4.y 0/3] db845c(sdm845) PM runtime fixes

[Amit Pundir]

On Mon, 29 Jan 2024 at 22:59, Amit Pundir <amit.pundir@linaro.org> wrote:
>
> On Mon, 29 Jan 2024 at 21:51, Greg KH <gregkh@linuxfoundation.org> wrote:
> >
> > On Mon, Jan 29, 2024 at 04:08:59PM +0530, Amit Pundir wrote:
> > > Hi,
> > >
> > > v5.4.y commit 31b169a8bed7 ("drm/msm/dsi: Use pm_runtime_resume_and_get
> > > to prevent refcnt leaks"), which is commit 3d07a411b4fa upstream, broke
> > > display on Dragonboard 845c(sdm845). Cherry-picking commit 6ab502bc1cf3
> > > ("drm/msm/dsi: Enable runtime PM") from the original patch series
> > > https://patchwork.freedesktop.org/series/119583/
> > > and it's dependent runtime PM helper routines as suggested by Dmitry
> > > https://lore.kernel.org/stable/CAA8EJpo7q9qZbgXHWe7SuQFh0EWW0ZxGL5xYX4nckoFGoGAtPw@mail.gmail.com
> > > fixes that display regression on DB845c.
> >
> > We need fixes for all of the newer stable trees too, you can't fix an
> > issue in an old tree and then if you upgraded, you would run into that
> > issue again.
> >
> > So please, resend this series as a set of series for all active lts
> > kernels, and we will be glad to queue them up.
>
> Ack. I'll send the patch series for all the active LTS kernels
> tomorrow after build/boot testing them locally. Meanwhile please
> consider this patch series for v5.4.y anyway.

Smoke tested and sent relevant fixes for other active LTS kernel
versions as well.

v5.10.y https://lore.kernel.org/stable/20240130124630.3867218-1-amit.pundir@linaro.org/T/

v5.15.y https://lore.kernel.org/stable/20240130125847.3915432-1-amit.pundir@linaro.org/T/

and v6.1.y+ https://lore.kernel.org/stable/20240130134647.58630-1-amit.pundir@linaro.org/T/

>
> Regards,
> Amit Pundir
>
> >
> > thanks,
> >
> > greg k-h

Re: [PATCH for-5.4.y 0/3] db845c(sdm845) PM runtime fixes

[Greg KH]

On Tue, Jan 30, 2024 at 07:22:28PM +0530, Amit Pundir wrote:
> On Mon, 29 Jan 2024 at 22:59, Amit Pundir <amit.pundir@linaro.org> wrote:
> >
> > On Mon, 29 Jan 2024 at 21:51, Greg KH <gregkh@linuxfoundation.org> wrote:
> > >
> > > On Mon, Jan 29, 2024 at 04:08:59PM +0530, Amit Pundir wrote:
> > > > Hi,
> > > >
> > > > v5.4.y commit 31b169a8bed7 ("drm/msm/dsi: Use pm_runtime_resume_and_get
> > > > to prevent refcnt leaks"), which is commit 3d07a411b4fa upstream, broke
> > > > display on Dragonboard 845c(sdm845). Cherry-picking commit 6ab502bc1cf3
> > > > ("drm/msm/dsi: Enable runtime PM") from the original patch series
> > > > https://patchwork.freedesktop.org/series/119583/
> > > > and it's dependent runtime PM helper routines as suggested by Dmitry
> > > > https://lore.kernel.org/stable/CAA8EJpo7q9qZbgXHWe7SuQFh0EWW0ZxGL5xYX4nckoFGoGAtPw@mail.gmail.com
> > > > fixes that display regression on DB845c.
> > >
> > > We need fixes for all of the newer stable trees too, you can't fix an
> > > issue in an old tree and then if you upgraded, you would run into that
> > > issue again.
> > >
> > > So please, resend this series as a set of series for all active lts
> > > kernels, and we will be glad to queue them up.
> >
> > Ack. I'll send the patch series for all the active LTS kernels
> > tomorrow after build/boot testing them locally. Meanwhile please
> > consider this patch series for v5.4.y anyway.
> 
> Smoke tested and sent relevant fixes for other active LTS kernel
> versions as well.
> 
> v5.10.y https://lore.kernel.org/stable/20240130124630.3867218-1-amit.pundir@linaro.org/T/
> 
> v5.15.y https://lore.kernel.org/stable/20240130125847.3915432-1-amit.pundir@linaro.org/T/
> 
> and v6.1.y+ https://lore.kernel.org/stable/20240130134647.58630-1-amit.pundir@linaro.org/T/

Sorry for the long delay, been busy :(

All now queued up.

greg k-h