[PATCH v4 1/3] PM: wakeup: Add routine to help fetch wakeup source object.

[PATCH v4 1/3] PM: wakeup: Add routine to help fetch wakeup source object.

[Ran Wang]

Some user might want to go through all registered wakeup sources
and doing things accordingly. For example, SoC PM driver might need to
do HW programming to prevent powering down specific IP which wakeup
source depending on. And is user's responsibility to identify if this
wakeup source he is interested in.

Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
---
Change in v4:
	- None.

Change in v3:
	- Adjust indentation of *attached_dev;.

Change in v2:
	- None.

 drivers/base/power/wakeup.c |   18 ++++++++++++++++++
 include/linux/pm_wakeup.h   |    3 +++
 2 files changed, 21 insertions(+), 0 deletions(-)

diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
index 5b2b6a0..6904485 100644
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -14,6 +14,7 @@
 #include <linux/suspend.h>
 #include <linux/seq_file.h>
 #include <linux/debugfs.h>
+#include <linux/of_device.h>
 #include <linux/pm_wakeirq.h>
 #include <trace/events/power.h>
 
@@ -226,6 +227,22 @@ void wakeup_source_unregister(struct wakeup_source *ws)
 	}
 }
 EXPORT_SYMBOL_GPL(wakeup_source_unregister);
+/**
+ * wakeup_source_get_next - Get next wakeup source from the list
+ * @ws: Previous wakeup source object, null means caller want first one.
+ */
+struct wakeup_source *wakeup_source_get_next(struct wakeup_source *ws)
+{
+	struct list_head *ws_head = &wakeup_sources;
+
+	if (ws)
+		return list_next_or_null_rcu(ws_head, &ws->entry,
+				struct wakeup_source, entry);
+	else
+		return list_entry_rcu(ws_head->next,
+				struct wakeup_source, entry);
+}
+EXPORT_SYMBOL_GPL(wakeup_source_get_next);
 
 /**
  * device_wakeup_attach - Attach a wakeup source object to a device object.
@@ -242,6 +259,7 @@ static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws)
 		return -EEXIST;
 	}
 	dev->power.wakeup = ws;
+	ws->attached_dev = dev;
 	if (dev->power.wakeirq)
 		device_wakeup_attach_irq(dev, dev->power.wakeirq);
 	spin_unlock_irq(&dev->power.lock);
diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h
index 0ff134d..913b2fb 100644
--- a/include/linux/pm_wakeup.h
+++ b/include/linux/pm_wakeup.h
@@ -50,6 +50,7 @@
  * @wakeup_count: Number of times the wakeup source might abort suspend.
  * @active: Status of the wakeup source.
  * @has_timeout: The wakeup source has been activated with a timeout.
+ * @attached_dev: The device it attached to
  */
 struct wakeup_source {
 	const char 		*name;
@@ -70,6 +71,7 @@ struct wakeup_source {
 	unsigned long		wakeup_count;
 	bool			active:1;
 	bool			autosleep_enabled:1;
+	struct device		*attached_dev;
 };
 
 #ifdef CONFIG_PM_SLEEP
@@ -101,6 +103,7 @@ static inline void device_set_wakeup_path(struct device *dev)
 extern void wakeup_source_remove(struct wakeup_source *ws);
 extern struct wakeup_source *wakeup_source_register(const char *name);
 extern void wakeup_source_unregister(struct wakeup_source *ws);
+extern struct wakeup_source *wakeup_source_get_next(struct wakeup_source *ws);
 extern int device_wakeup_enable(struct device *dev);
 extern int device_wakeup_disable(struct device *dev);
 extern void device_set_wakeup_capable(struct device *dev, bool capable);
-- 
1.7.1

[PATCH v4 2/3] Documentation: dt: binding: fsl: Add 'little-endian' and update Chassis define

[Ran Wang]

By default, QorIQ SoC's RCPM register block is Big Endian. But
there are some exceptions, such as LS1088A and LS2088A, are Little
Endian. So add this optional property to help identify them.

Actually LS2021A and other Layerscapes won't totally follow Chassis
2.1, so separate them from powerpc SoC.

Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
---
Change in v4:
	- Adjust indectation of 'ls1021a, ls1012a, ls1043a, ls1046a'.

Change in v3:
	- None.

Change in v2:
	- None.

 Documentation/devicetree/bindings/soc/fsl/rcpm.txt |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/Documentation/devicetree/bindings/soc/fsl/rcpm.txt b/Documentation/devicetree/bindings/soc/fsl/rcpm.txt
index e284e4e..058154c 100644
--- a/Documentation/devicetree/bindings/soc/fsl/rcpm.txt
+++ b/Documentation/devicetree/bindings/soc/fsl/rcpm.txt
@@ -20,6 +20,7 @@ Required properites:
 	* "fsl,qoriq-rcpm-1.0": for chassis 1.0 rcpm
 	* "fsl,qoriq-rcpm-2.0": for chassis 2.0 rcpm
 	* "fsl,qoriq-rcpm-2.1": for chassis 2.1 rcpm
+	* "fsl,qoriq-rcpm-2.1+": for chassis 2.1+ rcpm
 
 All references to "1.0" and "2.0" refer to the QorIQ chassis version to
 which the chip complies.
@@ -27,7 +28,12 @@ Chassis Version		Example Chips
 ---------------		-------------------------------
 1.0				p4080, p5020, p5040, p2041, p3041
 2.0				t4240, b4860, b4420
-2.1				t1040, ls1021
+2.1				t1040,
+2.1+				ls1021a, ls1012a, ls1043a, ls1046a
+
+Optional properties:
+ - little-endian : RCPM register block is Little Endian. Without it RCPM
+   will be Big Endian (default case).
 
 Example:
 The RCPM node for T4240:
-- 
1.7.1

[PATCH v4 3/3] soc: fsl: add RCPM driver

[Ran Wang]

The NXP's QorIQ Processors based on ARM Core have RCPM module
(Run Control and Power Management), which performs all device-level
tasks associated with power management such as wakeup source control.

This driver depends on PM wakeup source framework which help to
collect wake information.

Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
---
Change in v4:
	- Remove extra ',' in author line of rcpm.c
	- Update usage of wakeup_source_get_next() to be less confusing to the
	  reader, code logic remain the same.

Change in v3:
	- Some whitespace ajdustment.

Change in v2:
	- Rebase Kconfig and Makefile update to latest mainline.

 drivers/soc/fsl/Kconfig  |    8 +++
 drivers/soc/fsl/Makefile |    1 +
 drivers/soc/fsl/rcpm.c   |  122 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 131 insertions(+), 0 deletions(-)
 create mode 100644 drivers/soc/fsl/rcpm.c

diff --git a/drivers/soc/fsl/Kconfig b/drivers/soc/fsl/Kconfig
index 61f8e14..8e84e40 100644
--- a/drivers/soc/fsl/Kconfig
+++ b/drivers/soc/fsl/Kconfig
@@ -29,4 +29,12 @@ config FSL_MC_DPIO
 	  other DPAA2 objects. This driver does not expose the DPIO
 	  objects individually, but groups them under a service layer
 	  API.
+
+config FSL_RCPM
+	bool "Freescale RCPM support"
+	depends on PM_SLEEP
+	help
+	  The NXP's QorIQ Processors based on ARM Core have RCPM module
+	  (Run Control and Power Management), which performs all device-level
+	  tasks associated with power management, such as wakeup source control.
 endmenu
diff --git a/drivers/soc/fsl/Makefile b/drivers/soc/fsl/Makefile
index 803ef1b..c1be6ee 100644
--- a/drivers/soc/fsl/Makefile
+++ b/drivers/soc/fsl/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_QUICC_ENGINE)		+= qe/
 obj-$(CONFIG_CPM)			+= qe/
 obj-$(CONFIG_FSL_GUTS)			+= guts.o
 obj-$(CONFIG_FSL_MC_DPIO) 		+= dpio/
+obj-$(CONFIG_FSL_RCPM)		+= rcpm.o
diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c
new file mode 100644
index 0000000..ff27adc
--- /dev/null
+++ b/drivers/soc/fsl/rcpm.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// rcpm.c - Freescale QorIQ RCPM driver
+//
+// Copyright 2019 NXP
+//
+// Author: Ran Wang <ran.wang_1@nxp.com>
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/suspend.h>
+#include <linux/kernel.h>
+
+#define RCPM_WAKEUP_CELL_MAX_SIZE	7
+
+struct rcpm {
+	unsigned int	wakeup_cells;
+	void __iomem	*ippdexpcr_base;
+	bool		little_endian;
+};
+
+static int rcpm_pm_prepare(struct device *dev)
+{
+	struct device_node	*np = dev->of_node;
+	struct wakeup_source	*ws;
+	struct rcpm		*rcpm;
+	u32 value[RCPM_WAKEUP_CELL_MAX_SIZE + 1], tmp;
+	int i, ret;
+
+	rcpm = dev_get_drvdata(dev);
+	if (!rcpm)
+		return -EINVAL;
+
+	/* Begin with first registered wakeup source */
+	ws = NULL;
+	while (wakeup_source_get_next(ws)) {
+		ret = device_property_read_u32_array(ws->attached_dev,
+				"fsl,rcpm-wakeup", value, rcpm->wakeup_cells + 1);
+
+		/*  Wakeup source should refer to current rcpm device */
+		if (ret || (np->phandle != value[0])) {
+			dev_info(dev, "%s doesn't refer to this rcpm\n",
+					ws->name);
+			continue;
+		}
+
+		for (i = 0; i < rcpm->wakeup_cells; i++) {
+			/* We can only OR related bits */
+			if (value[i + 1]) {
+				if (rcpm->little_endian) {
+					tmp = ioread32(rcpm->ippdexpcr_base + i * 4);
+					tmp |= value[i + 1];
+					iowrite32(tmp, rcpm->ippdexpcr_base + i * 4);
+				} else {
+					tmp = ioread32be(rcpm->ippdexpcr_base + i * 4);
+					tmp |= value[i + 1];
+					iowrite32be(tmp, rcpm->ippdexpcr_base + i * 4);
+				}
+			}
+		}
+	}
+
+	return 0;
+}
+
+static const struct dev_pm_ops rcpm_pm_ops = {
+	.prepare =  rcpm_pm_prepare,
+};
+
+static int rcpm_probe(struct platform_device *pdev)
+{
+	struct device	*dev = &pdev->dev;
+	struct resource *r;
+	struct rcpm	*rcpm;
+	int ret;
+
+	rcpm = devm_kzalloc(dev, sizeof(*rcpm), GFP_KERNEL);
+	if (!rcpm)
+		return -ENOMEM;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r)
+		return -ENODEV;
+
+	rcpm->ippdexpcr_base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(rcpm->ippdexpcr_base)) {
+		ret =  PTR_ERR(rcpm->ippdexpcr_base);
+		return ret;
+	}
+
+	rcpm->little_endian = device_property_read_bool(
+			&pdev->dev, "little-endian");
+
+	ret = device_property_read_u32(&pdev->dev,
+			"fsl,#rcpm-wakeup-cells", &rcpm->wakeup_cells);
+	if (ret)
+		return ret;
+
+	dev_set_drvdata(&pdev->dev, rcpm);
+
+	return 0;
+}
+
+static const struct of_device_id rcpm_of_match[] = {
+	{ .compatible = "fsl,qoriq-rcpm-2.1+", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, rcpm_of_match);
+
+static struct platform_driver rcpm_driver = {
+	.driver = {
+		.name = "rcpm",
+		.of_match_table = rcpm_of_match,
+		.pm	= &rcpm_pm_ops,
+	},
+	.probe = rcpm_probe,
+};
+
+module_platform_driver(rcpm_driver);
-- 
1.7.1

RE: [PATCH v4 1/3] PM: wakeup: Add routine to help fetch wakeup source object.

[Ran Wang]

Hi Sirs,
    Could anyone please comment this patch set or tell me if I have missed
maintainer in mail list? I'd like to let review process move forward.
    Thank you.

Regards, 
Ran

On Monday, May 20, 2019 17:53 Ran Wang wrote:
> 
> Some user might want to go through all registered wakeup sources and doing
> things accordingly. For example, SoC PM driver might need to do HW
> programming to prevent powering down specific IP which wakeup source
> depending on. And is user's responsibility to identify if this wakeup source he is
> interested in.
> 
> Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
> ---
> Change in v4:
> 	- None.
> 
> Change in v3:
> 	- Adjust indentation of *attached_dev;.
> 
> Change in v2:
> 	- None.
> 
>  drivers/base/power/wakeup.c |   18 ++++++++++++++++++
>  include/linux/pm_wakeup.h   |    3 +++
>  2 files changed, 21 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index
> 5b2b6a0..6904485 100644
> --- a/drivers/base/power/wakeup.c
> +++ b/drivers/base/power/wakeup.c
> @@ -14,6 +14,7 @@
>  #include <linux/suspend.h>
>  #include <linux/seq_file.h>
>  #include <linux/debugfs.h>
> +#include <linux/of_device.h>
>  #include <linux/pm_wakeirq.h>
>  #include <trace/events/power.h>
> 
> @@ -226,6 +227,22 @@ void wakeup_source_unregister(struct wakeup_source
> *ws)
>  	}
>  }
>  EXPORT_SYMBOL_GPL(wakeup_source_unregister);
> +/**
> + * wakeup_source_get_next - Get next wakeup source from the list
> + * @ws: Previous wakeup source object, null means caller want first one.
> + */
> +struct wakeup_source *wakeup_source_get_next(struct wakeup_source *ws)
> +{
> +	struct list_head *ws_head = &wakeup_sources;
> +
> +	if (ws)
> +		return list_next_or_null_rcu(ws_head, &ws->entry,
> +				struct wakeup_source, entry);
> +	else
> +		return list_entry_rcu(ws_head->next,
> +				struct wakeup_source, entry);
> +}
> +EXPORT_SYMBOL_GPL(wakeup_source_get_next);
> 
>  /**
>   * device_wakeup_attach - Attach a wakeup source object to a device object.
> @@ -242,6 +259,7 @@ static int device_wakeup_attach(struct device *dev,
> struct wakeup_source *ws)
>  		return -EEXIST;
>  	}
>  	dev->power.wakeup = ws;
> +	ws->attached_dev = dev;
>  	if (dev->power.wakeirq)
>  		device_wakeup_attach_irq(dev, dev->power.wakeirq);
>  	spin_unlock_irq(&dev->power.lock);
> diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h index
> 0ff134d..913b2fb 100644
> --- a/include/linux/pm_wakeup.h
> +++ b/include/linux/pm_wakeup.h
> @@ -50,6 +50,7 @@
>   * @wakeup_count: Number of times the wakeup source might abort suspend.
>   * @active: Status of the wakeup source.
>   * @has_timeout: The wakeup source has been activated with a timeout.
> + * @attached_dev: The device it attached to
>   */
>  struct wakeup_source {
>  	const char 		*name;
> @@ -70,6 +71,7 @@ struct wakeup_source {
>  	unsigned long		wakeup_count;
>  	bool			active:1;
>  	bool			autosleep_enabled:1;
> +	struct device		*attached_dev;
>  };
> 
>  #ifdef CONFIG_PM_SLEEP
> @@ -101,6 +103,7 @@ static inline void device_set_wakeup_path(struct device
> *dev)  extern void wakeup_source_remove(struct wakeup_source *ws);  extern
> struct wakeup_source *wakeup_source_register(const char *name);  extern
> void wakeup_source_unregister(struct wakeup_source *ws);
> +extern struct wakeup_source *wakeup_source_get_next(struct
> +wakeup_source *ws);
>  extern int device_wakeup_enable(struct device *dev);  extern int
> device_wakeup_disable(struct device *dev);  extern void
> device_set_wakeup_capable(struct device *dev, bool capable);
> --
> 1.7.1

Re: [PATCH v4 2/3] Documentation: dt: binding: fsl: Add 'little-endian' and update Chassis define

[Rob Herring]

On Mon, 20 May 2019 17:52:37 +0800, Ran Wang wrote:
> By default, QorIQ SoC's RCPM register block is Big Endian. But
> there are some exceptions, such as LS1088A and LS2088A, are Little
> Endian. So add this optional property to help identify them.
> 
> Actually LS2021A and other Layerscapes won't totally follow Chassis
> 2.1, so separate them from powerpc SoC.
> 
> Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
> ---
> Change in v4:
> 	- Adjust indectation of 'ls1021a, ls1012a, ls1043a, ls1046a'.
> 
> Change in v3:
> 	- None.
> 
> Change in v2:
> 	- None.
> 
>  Documentation/devicetree/bindings/soc/fsl/rcpm.txt |    8 +++++++-
>  1 files changed, 7 insertions(+), 1 deletions(-)
> 

Reviewed-by: Rob Herring <robh@kernel.org>

Re: [PATCH v4 1/3] PM: wakeup: Add routine to help fetch wakeup source object.

[Rafael J. Wysocki]

On Monday, May 20, 2019 11:52:36 AM CEST Ran Wang wrote:
> Some user might want to go through all registered wakeup sources
> and doing things accordingly. For example, SoC PM driver might need to
> do HW programming to prevent powering down specific IP which wakeup
> source depending on. And is user's responsibility to identify if this
> wakeup source he is interested in.

I guess the idea here is that you need to walk wakeup devices and you noticed
that there was a wakeup source object for each of them and those wakeup
source objects were on a list, so you could walk wakeup devices by walking
the list of wakeup source objects.

That is fair enough, but the changelog above doesn't even talk about that.
 
> Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
> ---
> Change in v4:
> 	- None.
> 
> Change in v3:
> 	- Adjust indentation of *attached_dev;.
> 
> Change in v2:
> 	- None.
> 
>  drivers/base/power/wakeup.c |   18 ++++++++++++++++++
>  include/linux/pm_wakeup.h   |    3 +++
>  2 files changed, 21 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
> index 5b2b6a0..6904485 100644
> --- a/drivers/base/power/wakeup.c
> +++ b/drivers/base/power/wakeup.c
> @@ -14,6 +14,7 @@
>  #include <linux/suspend.h>
>  #include <linux/seq_file.h>
>  #include <linux/debugfs.h>
> +#include <linux/of_device.h>
>  #include <linux/pm_wakeirq.h>
>  #include <trace/events/power.h>
>  
> @@ -226,6 +227,22 @@ void wakeup_source_unregister(struct wakeup_source *ws)
>  	}
>  }
>  EXPORT_SYMBOL_GPL(wakeup_source_unregister);
> +/**
> + * wakeup_source_get_next - Get next wakeup source from the list
> + * @ws: Previous wakeup source object, null means caller want first one.
> + */
> +struct wakeup_source *wakeup_source_get_next(struct wakeup_source *ws)
> +{
> +	struct list_head *ws_head = &wakeup_sources;
> +
> +	if (ws)
> +		return list_next_or_null_rcu(ws_head, &ws->entry,
> +				struct wakeup_source, entry);
> +	else
> +		return list_entry_rcu(ws_head->next,
> +				struct wakeup_source, entry);
> +}
> +EXPORT_SYMBOL_GPL(wakeup_source_get_next);

This needs to be arranged along the lines of wakeup_sources_stats_seq_start/next/stop()
because of the SRCU protection of the list.

>  
>  /**
>   * device_wakeup_attach - Attach a wakeup source object to a device object.
> @@ -242,6 +259,7 @@ static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws)
>  		return -EEXIST;
>  	}
>  	dev->power.wakeup = ws;
> +	ws->attached_dev = dev;
>  	if (dev->power.wakeirq)
>  		device_wakeup_attach_irq(dev, dev->power.wakeirq);
>  	spin_unlock_irq(&dev->power.lock);
> diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h
> index 0ff134d..913b2fb 100644
> --- a/include/linux/pm_wakeup.h
> +++ b/include/linux/pm_wakeup.h
> @@ -50,6 +50,7 @@
>   * @wakeup_count: Number of times the wakeup source might abort suspend.
>   * @active: Status of the wakeup source.
>   * @has_timeout: The wakeup source has been activated with a timeout.
> + * @attached_dev: The device it attached to
>   */
>  struct wakeup_source {
>  	const char 		*name;
> @@ -70,6 +71,7 @@ struct wakeup_source {
>  	unsigned long		wakeup_count;
>  	bool			active:1;
>  	bool			autosleep_enabled:1;
> +	struct device		*attached_dev;

Please (a) call it just dev and (b) move it up (before wakeirq, say).

>  };
>  
>  #ifdef CONFIG_PM_SLEEP
> @@ -101,6 +103,7 @@ static inline void device_set_wakeup_path(struct device *dev)
>  extern void wakeup_source_remove(struct wakeup_source *ws);
>  extern struct wakeup_source *wakeup_source_register(const char *name);
>  extern void wakeup_source_unregister(struct wakeup_source *ws);
> +extern struct wakeup_source *wakeup_source_get_next(struct wakeup_source *ws);
>  extern int device_wakeup_enable(struct device *dev);
>  extern int device_wakeup_disable(struct device *dev);
>  extern void device_set_wakeup_capable(struct device *dev, bool capable);
> 

RE: [PATCH v4 1/3] PM: wakeup: Add routine to help fetch wakeup source object.

[Ran Wang]

Hi Rafael,

On Wednesday, June 19, 2019 06:45, Rafael J. Wysocki wrote:
> 
> On Monday, May 20, 2019 11:52:36 AM CEST Ran Wang wrote:
> > Some user might want to go through all registered wakeup sources and
> > doing things accordingly. For example, SoC PM driver might need to do
> > HW programming to prevent powering down specific IP which wakeup
> > source depending on. And is user's responsibility to identify if this
> > wakeup source he is interested in.
> 
> I guess the idea here is that you need to walk wakeup devices and you noticed
> that there was a wakeup source object for each of them and those wakeup
> source objects were on a list, so you could walk wakeup devices by walking the
> list of wakeup source objects.
> 
> That is fair enough, but the changelog above doesn't even talk about that.

How about this:
"Providing a API for helping walk through all registered wakeup devices on the list.
It will be useful for SoC PMU driver to know which device will work as a wakeup
source then do specific HW programming for them."

> > Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
> > ---
> > Change in v4:
> > 	- None.
> >
> > Change in v3:
> > 	- Adjust indentation of *attached_dev;.
> >
> > Change in v2:
> > 	- None.
> >
> >  drivers/base/power/wakeup.c |   18 ++++++++++++++++++
> >  include/linux/pm_wakeup.h   |    3 +++
> >  2 files changed, 21 insertions(+), 0 deletions(-)
> >
> > diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
> > index 5b2b6a0..6904485 100644
> > --- a/drivers/base/power/wakeup.c
> > +++ b/drivers/base/power/wakeup.c
> > @@ -14,6 +14,7 @@
> >  #include <linux/suspend.h>
> >  #include <linux/seq_file.h>
> >  #include <linux/debugfs.h>
> > +#include <linux/of_device.h>
> >  #include <linux/pm_wakeirq.h>
> >  #include <trace/events/power.h>
> >
> > @@ -226,6 +227,22 @@ void wakeup_source_unregister(struct
> wakeup_source *ws)
> >  	}
> >  }
> >  EXPORT_SYMBOL_GPL(wakeup_source_unregister);
> > +/**
> > + * wakeup_source_get_next - Get next wakeup source from the list
> > + * @ws: Previous wakeup source object, null means caller want first one.
> > + */
> > +struct wakeup_source *wakeup_source_get_next(struct wakeup_source
> > +*ws) {
> > +	struct list_head *ws_head = &wakeup_sources;
> > +
> > +	if (ws)
> > +		return list_next_or_null_rcu(ws_head, &ws->entry,
> > +				struct wakeup_source, entry);
> > +	else
> > +		return list_entry_rcu(ws_head->next,
> > +				struct wakeup_source, entry);
> > +}
> > +EXPORT_SYMBOL_GPL(wakeup_source_get_next);
> 
> This needs to be arranged along the lines of
> wakeup_sources_stats_seq_start/next/stop()
> because of the SRCU protection of the list.

Got it, how about this:
 230 /**                                                                              
 231  * wakeup_source_get_next - Get next wakeup source from the list                 
 232  * @ws: Previous wakeup source object, null means caller want first one.         
 233  */                                                                              
 234 struct wakeup_source *wakeup_source_get_next(struct wakeup_source *ws)           
 235 {                                                                                
 236         struct list_head *ws_head = &wakeup_sources;                             
 237         struct wakeup_source *next_ws = NULL;                                    
 238         int idx;                                                                 
 239                                                                                  
 240         idx = srcu_read_lock(&wakeup_srcu);                                      
 241         if (ws)                                                                                                                
 242                 next_ws = list_next_or_null_rcu(ws_head, &ws->entry,             
 243                                 struct wakeup_source, entry);                    
 244         else                                                                     
 245                 next_ws = list_entry_rcu(ws_head->next,                          
 246                                 struct wakeup_source, entry);                    
 247         srcu_read_unlock(&wakeup_srcu, idx);                                     
 248                                                                                  
 249         return next_ws;                                                          
 250 }                                                                                
 251 EXPORT_SYMBOL_GPL(wakeup_source_get_next);   

> >
> >  /**
> >   * device_wakeup_attach - Attach a wakeup source object to a device object.
> > @@ -242,6 +259,7 @@ static int device_wakeup_attach(struct device *dev,
> struct wakeup_source *ws)
> >  		return -EEXIST;
> >  	}
> >  	dev->power.wakeup = ws;
> > +	ws->attached_dev = dev;
> >  	if (dev->power.wakeirq)
> >  		device_wakeup_attach_irq(dev, dev->power.wakeirq);
> >  	spin_unlock_irq(&dev->power.lock);
> > diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h
> > index 0ff134d..913b2fb 100644
> > --- a/include/linux/pm_wakeup.h
> > +++ b/include/linux/pm_wakeup.h
> > @@ -50,6 +50,7 @@
> >   * @wakeup_count: Number of times the wakeup source might abort suspend.
> >   * @active: Status of the wakeup source.
> >   * @has_timeout: The wakeup source has been activated with a timeout.
> > + * @attached_dev: The device it attached to
> >   */
> >  struct wakeup_source {
> >  	const char 		*name;
> > @@ -70,6 +71,7 @@ struct wakeup_source {
> >  	unsigned long		wakeup_count;
> >  	bool			active:1;
> >  	bool			autosleep_enabled:1;
> > +	struct device		*attached_dev;
> 
> Please (a) call it just dev and (b) move it up (before wakeirq, say)

Got it, will update in next version.

Thanks & Regards,
Ran
> 
> >  };
> >
> >  #ifdef CONFIG_PM_SLEEP
> > @@ -101,6 +103,7 @@ static inline void device_set_wakeup_path(struct
> > device *dev)  extern void wakeup_source_remove(struct wakeup_source
> > *ws);  extern struct wakeup_source *wakeup_source_register(const char
> > *name);  extern void wakeup_source_unregister(struct wakeup_source
> > *ws);
> > +extern struct wakeup_source *wakeup_source_get_next(struct
> > +wakeup_source *ws);
> >  extern int device_wakeup_enable(struct device *dev);  extern int
> > device_wakeup_disable(struct device *dev);  extern void
> > device_set_wakeup_capable(struct device *dev, bool capable);
> >
> 
> 
>