[S390] pm: css bus power management callbacks (dcbd16d5) · Commits · jan.koester / Linux

drivers/s390/cio/chsc.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -549,8 +549,7 @@ chsc_add_cmg_attr(struct channel_subsystem *css)
		return ret;
		}

		static int
		__chsc_do_secm(struct channel_subsystem css, int enable, void page)
		int __chsc_do_secm(struct channel_subsystem css, int enable, void page)
		{
		struct {
		struct chsc_header request;

drivers/s390/cio/chsc.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -90,6 +90,7 @@ extern void chsc_free_sei_area(void);
		extern int chsc_enable_facility(int);
		struct channel_subsystem;
		extern int chsc_secm(struct channel_subsystem *, int);
		int __chsc_do_secm(struct channel_subsystem css, int enable, void page);

		int chsc_chp_vary(struct chp_id chpid, int on);
		int chsc_determine_channel_path_desc(struct chp_id chpid, int fmt, int rfmt,

drivers/s390/cio/css.c

+152 −5

Original line number	Diff line number	Diff line
		/*
		* drivers/s390/cio/css.c
		* driver for channel subsystem
		*
		* Copyright IBM Corp. 2002,2008
		* Copyright IBM Corp. 2002, 2009
		*
		* Author(s): Arnd Bergmann (arndb@de.ibm.com)
		* Cornelia Huck (cornelia.huck@de.ibm.com)
		*/
		@@ -17,6 +17,7 @@
		#include <linux/errno.h>
		#include <linux/list.h>
		#include <linux/reboot.h>
		#include <linux/suspend.h>
		#include <asm/isc.h>
		#include <asm/crw.h>

		@@ -779,6 +780,79 @@ static struct notifier_block css_reboot_notifier = {
		.notifier_call = css_reboot_event,
		};

		/*
		* Since the css devices are neither on a bus nor have a class
		* nor have a special device type, we cannot stop/restart channel
		* path measurements via the normal suspend/resume callbacks, but have
		* to use notifiers.
		*/
		static int css_power_event(struct notifier_block *this, unsigned long event,
		void *ptr)
		{
		void *secm_area;
		int ret, i;

		switch (event) {
		case PM_HIBERNATION_PREPARE:
		case PM_SUSPEND_PREPARE:
		ret = NOTIFY_DONE;
		for (i = 0; i <= __MAX_CSSID; i++) {
		struct channel_subsystem *css;

		css = channel_subsystems[i];
		mutex_lock(&css->mutex);
		if (!css->cm_enabled) {
		mutex_unlock(&css->mutex);
		continue;
		}
		secm_area = (void *)get_zeroed_page(GFP_KERNEL \|
		GFP_DMA);
		if (secm_area) {
		if (__chsc_do_secm(css, 0, secm_area))
		ret = NOTIFY_BAD;
		free_page((unsigned long)secm_area);
		} else
		ret = NOTIFY_BAD;

		mutex_unlock(&css->mutex);
		}
		break;
		case PM_POST_HIBERNATION:
		case PM_POST_SUSPEND:
		ret = NOTIFY_DONE;
		for (i = 0; i <= __MAX_CSSID; i++) {
		struct channel_subsystem *css;

		css = channel_subsystems[i];
		mutex_lock(&css->mutex);
		if (!css->cm_enabled) {
		mutex_unlock(&css->mutex);
		continue;
		}
		secm_area = (void *)get_zeroed_page(GFP_KERNEL \|
		GFP_DMA);
		if (secm_area) {
		if (__chsc_do_secm(css, 1, secm_area))
		ret = NOTIFY_BAD;
		free_page((unsigned long)secm_area);
		} else
		ret = NOTIFY_BAD;

		mutex_unlock(&css->mutex);
		}
		/* search for subchannels, which appeared during hibernation */
		css_schedule_reprobe();
		break;
		default:
		ret = NOTIFY_DONE;
		}
		return ret;

		}
		static struct notifier_block css_power_notifier = {
		.notifier_call = css_power_event,
		};

		/*
		* Now that the driver core is running, we can setup our channel subsystem.
		* The struct subchannel's are created during probing (except for the
		@@ -852,6 +926,11 @@ init_channel_subsystem (void)
		ret = register_reboot_notifier(&css_reboot_notifier);
		if (ret)
		goto out_unregister;
		ret = register_pm_notifier(&css_power_notifier);
		if (ret) {
		unregister_reboot_notifier(&css_reboot_notifier);
		goto out_unregister;
		}
		css_init_done = 1;

		/* Enable default isc for I/O subchannels. */
		@@ -953,6 +1032,73 @@ static int css_uevent(struct device dev, struct kobj_uevent_env env)
		return ret;
		}

		static int css_pm_prepare(struct device *dev)
		{
		struct subchannel *sch = to_subchannel(dev);
		struct css_driver *drv;

		if (mutex_is_locked(&sch->reg_mutex))
		return -EAGAIN;
		if (!sch->dev.driver)
		return 0;
		drv = to_cssdriver(sch->dev.driver);
		/* Notify drivers that they may not register children. */
		return drv->prepare ? drv->prepare(sch) : 0;
		}

		static void css_pm_complete(struct device *dev)
		{
		struct subchannel *sch = to_subchannel(dev);
		struct css_driver *drv;

		if (!sch->dev.driver)
		return;
		drv = to_cssdriver(sch->dev.driver);
		if (drv->complete)
		drv->complete(sch);
		}

		static int css_pm_freeze(struct device *dev)
		{
		struct subchannel *sch = to_subchannel(dev);
		struct css_driver *drv;

		if (!sch->dev.driver)
		return 0;
		drv = to_cssdriver(sch->dev.driver);
		return drv->freeze ? drv->freeze(sch) : 0;
		}

		static int css_pm_thaw(struct device *dev)
		{
		struct subchannel *sch = to_subchannel(dev);
		struct css_driver *drv;

		if (!sch->dev.driver)
		return 0;
		drv = to_cssdriver(sch->dev.driver);
		return drv->thaw ? drv->thaw(sch) : 0;
		}

		static int css_pm_restore(struct device *dev)
		{
		struct subchannel *sch = to_subchannel(dev);
		struct css_driver *drv;

		if (!sch->dev.driver)
		return 0;
		drv = to_cssdriver(sch->dev.driver);
		return drv->restore ? drv->restore(sch) : 0;
		}

		static struct dev_pm_ops css_pm_ops = {
		.prepare = css_pm_prepare,
		.complete = css_pm_complete,
		.freeze = css_pm_freeze,
		.thaw = css_pm_thaw,
		.restore = css_pm_restore,
		};

		struct bus_type css_bus_type = {
		.name = "css",
		.match = css_bus_match,
		@@ -960,6 +1106,7 @@ struct bus_type css_bus_type = {
		.remove = css_remove,
		.shutdown = css_shutdown,
		.uevent = css_uevent,
		.pm = &css_pm_ops,
		};

		/**

drivers/s390/cio/css.h

+10 −0

Original line number	Diff line number	Diff line
		@@ -70,6 +70,11 @@ struct chp_link;
		* @probe: function called on probe
		* @remove: function called on remove
		* @shutdown: called at device shutdown
		* @prepare: prepare for pm state transition
		* @complete: undo work done in @prepare
		* @freeze: callback for freezing during hibernation snapshotting
		* @thaw: undo work done in @freeze
		* @restore: callback for restoring after hibernation
		* @name: name of the device driver
		*/
		struct css_driver {
		@@ -82,6 +87,11 @@ struct css_driver {
		int (probe)(struct subchannel );
		int (remove)(struct subchannel );
		void (shutdown)(struct subchannel );
		int (prepare) (struct subchannel );
		void (complete) (struct subchannel );
		int (freeze)(struct subchannel );
		int (thaw) (struct subchannel );
		int (restore)(struct subchannel );
		const char *name;
		};