| Message ID | 1359985042-2610-1-git-send-email-jbarnes@virtuousgeek.org (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
On Monday, February 04, 2013 01:37:20 PM Jesse Barnes wrote: > KMS drivers can potentially restore the display configuration without > userspace help. Such drivers can can call a new funciton, > pm_vt_switch_required(false) if they support this feature. In that > case, the PM layer won't VT switch to the suspend console at suspend > time and then back to the original VT on resume, but rather leave things > alone for a nicer looking suspend and resume sequence. > > v2: make a function so we can handle multiple drivers (Alan) > v3: use a list to track device requests (Rafael) > > Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> for all [1-3/3]. Thanks, Rafael > --- > include/linux/pm.h | 4 ++ > kernel/power/console.c | 115 ++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 119 insertions(+) > > diff --git a/include/linux/pm.h b/include/linux/pm.h > index 03d7bb1..98310eb 100644 > --- a/include/linux/pm.h > +++ b/include/linux/pm.h > @@ -35,6 +35,10 @@ extern void (*pm_idle)(void); > extern void (*pm_power_off)(void); > extern void (*pm_power_off_prepare)(void); > > +struct device; /* we have a circular dep with device.h */ > +extern void pm_vt_switch_required(struct device *dev, bool required); > +extern void pm_vt_switch_unregister(struct device *dev); > + > /* > * Device power management > */ > diff --git a/kernel/power/console.c b/kernel/power/console.c > index b1dc456..4871ca9 100644 > --- a/kernel/power/console.c > +++ b/kernel/power/console.c > @@ -4,6 +4,7 @@ > * Originally from swsusp. > */ > > +#include <linux/console.h> > #include <linux/vt_kern.h> > #include <linux/kbd_kern.h> > #include <linux/vt.h> > @@ -14,8 +15,119 @@ > > static int orig_fgconsole, orig_kmsg; > > +DEFINE_MUTEX(vt_switch_mutex); > + > +struct pm_vt_switch { > + struct list_head head; > + struct device *dev; > + bool required; > +}; > + > +LIST_HEAD(pm_vt_switch_list); > + > + > +/** > + * pm_vt_switch_required - indicate VT switch at suspend requirements > + * @dev: device > + * @required: if true, caller needs VT switch at suspend/resume time > + * > + * The different console drivers may or may not require VT switches across > + * suspend/resume, depending on how they handle restoring video state and > + * what may be running. > + * > + * Drivers can indicate support for switchless suspend/resume, which can > + * save time and flicker, by using this routine and passing 'false' as > + * the argument. If any loaded driver needs VT switching, or the > + * no_console_suspend argument has been passed on the command line, VT > + * switches will occur. > + */ > +void pm_vt_switch_required(struct device *dev, bool required) > +{ > + struct pm_vt_switch *entry, *tmp; > + > + mutex_lock(&vt_switch_mutex); > + list_for_each_entry(tmp, &pm_vt_switch_list, head) { > + if (tmp->dev == dev) { > + /* already registered, update requirement */ > + tmp->required = required; > + goto out; > + } > + } > + > + entry = kmalloc(sizeof(*entry), GFP_KERNEL); > + if (!entry) > + goto out; > + > + entry->required = required; > + entry->dev = dev; > + > + list_add(&entry->head, &pm_vt_switch_list); > +out: > + mutex_unlock(&vt_switch_mutex); > +} > +EXPORT_SYMBOL(pm_vt_switch_required); > + > +/** > + * pm_vt_switch_unregister - stop tracking a device's VT switching needs > + * @dev: device > + * > + * Remove @dev from the vt switch list. > + */ > +void pm_vt_switch_unregister(struct device *dev) > +{ > + struct pm_vt_switch *tmp; > + > + mutex_lock(&vt_switch_mutex); > + list_for_each_entry(tmp, &pm_vt_switch_list, head) { > + if (tmp->dev == dev) { > + list_del(&tmp->head); > + break; > + } > + } > + mutex_unlock(&vt_switch_mutex); > +} > + > +/* > + * There are three cases when a VT switch on suspend/resume are required: > + * 1) no driver has indicated a requirement one way or another, so preserve > + * the old behavior > + * 2) console suspend is disabled, we want to see debug messages across > + * suspend/resume > + * 3) any registered driver indicates it needs a VT switch > + * > + * If none of these conditions is present, meaning we have at least one driver > + * that doesn't need the switch, and none that do, we can avoid it to make > + * resume look a little prettier (and suspend too, but that's usually hidden, > + * e.g. when closing the lid on a laptop). > + */ > +static bool pm_vt_switch(void) > +{ > + struct pm_vt_switch *entry; > + bool ret = true; > + > + mutex_lock(&vt_switch_mutex); > + if (list_empty(&pm_vt_switch_list)) > + goto out; > + > + if (!console_suspend_enabled) > + goto out; > + > + list_for_each_entry(entry, &pm_vt_switch_list, head) { > + if (entry->required) > + goto out; > + } > + > + ret = false; > +out: > + mutex_unlock(&vt_switch_mutex); > + return ret; > +} > + > int pm_prepare_console(void) > { > + if (!pm_vt_switch()) > + return 0; > + > orig_fgconsole = vt_move_to_console(SUSPEND_CONSOLE, 1); > if (orig_fgconsole < 0) > return 1; > @@ -26,6 +138,9 @@ int pm_prepare_console(void) > > void pm_restore_console(void) > { > + if (!pm_vt_switch()) > + return; > + > if (orig_fgconsole >= 0) { > vt_move_to_console(orig_fgconsole, 0); > vt_kmsg_redirect(orig_kmsg); >
On Mon, 04 Feb 2013 21:26:26 +0100 "Rafael J. Wysocki" <rjw@sisk.pl> wrote: > On Monday, February 04, 2013 01:37:20 PM Jesse Barnes wrote: > > KMS drivers can potentially restore the display configuration without > > userspace help. Such drivers can can call a new funciton, > > pm_vt_switch_required(false) if they support this feature. In that > > case, the PM layer won't VT switch to the suspend console at suspend > > time and then back to the original VT on resume, but rather leave things > > alone for a nicer looking suspend and resume sequence. > > > > v2: make a function so we can handle multiple drivers (Alan) > > v3: use a list to track device requests (Rafael) > > > > Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> > > Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > for all [1-3/3]. Any chance for an r-b on the PM one at least? Then Daniel could probably push this through drm-intel-next. Thanks, Jesse -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Monday, February 04, 2013 01:37:20 PM Jesse Barnes wrote: > KMS drivers can potentially restore the display configuration without > userspace help. Such drivers can can call a new funciton, > pm_vt_switch_required(false) if they support this feature. In that > case, the PM layer won't VT switch to the suspend console at suspend > time and then back to the original VT on resume, but rather leave things > alone for a nicer looking suspend and resume sequence. > > v2: make a function so we can handle multiple drivers (Alan) > v3: use a list to track device requests (Rafael) > > Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > include/linux/pm.h | 4 ++ > kernel/power/console.c | 115 ++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 119 insertions(+) > > diff --git a/include/linux/pm.h b/include/linux/pm.h > index 03d7bb1..98310eb 100644 > --- a/include/linux/pm.h > +++ b/include/linux/pm.h > @@ -35,6 +35,10 @@ extern void (*pm_idle)(void); > extern void (*pm_power_off)(void); > extern void (*pm_power_off_prepare)(void); > > +struct device; /* we have a circular dep with device.h */ > +extern void pm_vt_switch_required(struct device *dev, bool required); > +extern void pm_vt_switch_unregister(struct device *dev); > + > /* > * Device power management > */ > diff --git a/kernel/power/console.c b/kernel/power/console.c > index b1dc456..4871ca9 100644 > --- a/kernel/power/console.c > +++ b/kernel/power/console.c > @@ -4,6 +4,7 @@ > * Originally from swsusp. > */ > > +#include <linux/console.h> > #include <linux/vt_kern.h> > #include <linux/kbd_kern.h> > #include <linux/vt.h> > @@ -14,8 +15,119 @@ > > static int orig_fgconsole, orig_kmsg; > > +DEFINE_MUTEX(vt_switch_mutex); > + > +struct pm_vt_switch { > + struct list_head head; > + struct device *dev; > + bool required; > +}; > + > +LIST_HEAD(pm_vt_switch_list); > + > + > +/** > + * pm_vt_switch_required - indicate VT switch at suspend requirements > + * @dev: device > + * @required: if true, caller needs VT switch at suspend/resume time > + * > + * The different console drivers may or may not require VT switches across > + * suspend/resume, depending on how they handle restoring video state and > + * what may be running. > + * > + * Drivers can indicate support for switchless suspend/resume, which can > + * save time and flicker, by using this routine and passing 'false' as > + * the argument. If any loaded driver needs VT switching, or the > + * no_console_suspend argument has been passed on the command line, VT > + * switches will occur. > + */ > +void pm_vt_switch_required(struct device *dev, bool required) > +{ > + struct pm_vt_switch *entry, *tmp; > + > + mutex_lock(&vt_switch_mutex); > + list_for_each_entry(tmp, &pm_vt_switch_list, head) { > + if (tmp->dev == dev) { > + /* already registered, update requirement */ > + tmp->required = required; > + goto out; > + } > + } > + > + entry = kmalloc(sizeof(*entry), GFP_KERNEL); > + if (!entry) > + goto out; > + > + entry->required = required; > + entry->dev = dev; > + > + list_add(&entry->head, &pm_vt_switch_list); > +out: > + mutex_unlock(&vt_switch_mutex); > +} > +EXPORT_SYMBOL(pm_vt_switch_required); > + > +/** > + * pm_vt_switch_unregister - stop tracking a device's VT switching needs > + * @dev: device > + * > + * Remove @dev from the vt switch list. > + */ > +void pm_vt_switch_unregister(struct device *dev) > +{ > + struct pm_vt_switch *tmp; > + > + mutex_lock(&vt_switch_mutex); > + list_for_each_entry(tmp, &pm_vt_switch_list, head) { > + if (tmp->dev == dev) { > + list_del(&tmp->head); > + break; > + } > + } > + mutex_unlock(&vt_switch_mutex); > +} > + > +/* > + * There are three cases when a VT switch on suspend/resume are required: > + * 1) no driver has indicated a requirement one way or another, so preserve > + * the old behavior > + * 2) console suspend is disabled, we want to see debug messages across > + * suspend/resume > + * 3) any registered driver indicates it needs a VT switch > + * > + * If none of these conditions is present, meaning we have at least one driver > + * that doesn't need the switch, and none that do, we can avoid it to make > + * resume look a little prettier (and suspend too, but that's usually hidden, > + * e.g. when closing the lid on a laptop). > + */ > +static bool pm_vt_switch(void) > +{ > + struct pm_vt_switch *entry; > + bool ret = true; > + > + mutex_lock(&vt_switch_mutex); > + if (list_empty(&pm_vt_switch_list)) > + goto out; > + > + if (!console_suspend_enabled) > + goto out; > + > + list_for_each_entry(entry, &pm_vt_switch_list, head) { > + if (entry->required) > + goto out; > + } > + > + ret = false; > +out: > + mutex_unlock(&vt_switch_mutex); > + return ret; > +} > + > int pm_prepare_console(void) > { > + if (!pm_vt_switch()) > + return 0; > + > orig_fgconsole = vt_move_to_console(SUSPEND_CONSOLE, 1); > if (orig_fgconsole < 0) > return 1; > @@ -26,6 +138,9 @@ int pm_prepare_console(void) > > void pm_restore_console(void) > { > + if (!pm_vt_switch()) > + return; > + > if (orig_fgconsole >= 0) { > vt_move_to_console(orig_fgconsole, 0); > vt_kmsg_redirect(orig_kmsg); >
On Tuesday, February 05, 2013 01:55:44 PM Jesse Barnes wrote: > On Mon, 04 Feb 2013 21:26:26 +0100 > "Rafael J. Wysocki" <rjw@sisk.pl> wrote: > > > On Monday, February 04, 2013 01:37:20 PM Jesse Barnes wrote: > > > KMS drivers can potentially restore the display configuration without > > > userspace help. Such drivers can can call a new funciton, > > > pm_vt_switch_required(false) if they support this feature. In that > > > case, the PM layer won't VT switch to the suspend console at suspend > > > time and then back to the original VT on resume, but rather leave things > > > alone for a nicer looking suspend and resume sequence. > > > > > > v2: make a function so we can handle multiple drivers (Alan) > > > v3: use a list to track device requests (Rafael) > > > > > > Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> > > > > Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > > > for all [1-3/3]. > > Any chance for an r-b on the PM one at least? Then Daniel could > probably push this through drm-intel-next. Done. Thanks, Rafael
On Tue, Feb 05, 2013 at 11:02:17PM +0100, Rafael J. Wysocki wrote: > On Tuesday, February 05, 2013 01:55:44 PM Jesse Barnes wrote: > > On Mon, 04 Feb 2013 21:26:26 +0100 > > "Rafael J. Wysocki" <rjw@sisk.pl> wrote: > > > > > On Monday, February 04, 2013 01:37:20 PM Jesse Barnes wrote: > > > > KMS drivers can potentially restore the display configuration without > > > > userspace help. Such drivers can can call a new funciton, > > > > pm_vt_switch_required(false) if they support this feature. In that > > > > case, the PM layer won't VT switch to the suspend console at suspend > > > > time and then back to the original VT on resume, but rather leave things > > > > alone for a nicer looking suspend and resume sequence. > > > > > > > > v2: make a function so we can handle multiple drivers (Alan) > > > > v3: use a list to track device requests (Rafael) > > > > > > > > Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> > > > > > > Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > > > > > for all [1-3/3]. > > > > Any chance for an r-b on the PM one at least? Then Daniel could > > probably push this through drm-intel-next. > > Done. Thanks, I've merged the first two patches to drm-intel-next, the i915 one still needs a bit of care imo. -Daniel
diff --git a/include/linux/pm.h b/include/linux/pm.h index 03d7bb1..98310eb 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -35,6 +35,10 @@ extern void (*pm_idle)(void); extern void (*pm_power_off)(void); extern void (*pm_power_off_prepare)(void); +struct device; /* we have a circular dep with device.h */ +extern void pm_vt_switch_required(struct device *dev, bool required); +extern void pm_vt_switch_unregister(struct device *dev); + /* * Device power management */ diff --git a/kernel/power/console.c b/kernel/power/console.c index b1dc456..4871ca9 100644 --- a/kernel/power/console.c +++ b/kernel/power/console.c @@ -4,6 +4,7 @@ * Originally from swsusp. */ +#include <linux/console.h> #include <linux/vt_kern.h> #include <linux/kbd_kern.h> #include <linux/vt.h> @@ -14,8 +15,119 @@ static int orig_fgconsole, orig_kmsg; +DEFINE_MUTEX(vt_switch_mutex); + +struct pm_vt_switch { + struct list_head head; + struct device *dev; + bool required; +}; + +LIST_HEAD(pm_vt_switch_list); + + +/** + * pm_vt_switch_required - indicate VT switch at suspend requirements + * @dev: device + * @required: if true, caller needs VT switch at suspend/resume time + * + * The different console drivers may or may not require VT switches across + * suspend/resume, depending on how they handle restoring video state and + * what may be running. + * + * Drivers can indicate support for switchless suspend/resume, which can + * save time and flicker, by using this routine and passing 'false' as + * the argument. If any loaded driver needs VT switching, or the + * no_console_suspend argument has been passed on the command line, VT + * switches will occur. + */ +void pm_vt_switch_required(struct device *dev, bool required) +{ + struct pm_vt_switch *entry, *tmp; + + mutex_lock(&vt_switch_mutex); + list_for_each_entry(tmp, &pm_vt_switch_list, head) { + if (tmp->dev == dev) { + /* already registered, update requirement */ + tmp->required = required; + goto out; + } + } + + entry = kmalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + goto out; + + entry->required = required; + entry->dev = dev; + + list_add(&entry->head, &pm_vt_switch_list); +out: + mutex_unlock(&vt_switch_mutex); +} +EXPORT_SYMBOL(pm_vt_switch_required); + +/** + * pm_vt_switch_unregister - stop tracking a device's VT switching needs + * @dev: device + * + * Remove @dev from the vt switch list. + */ +void pm_vt_switch_unregister(struct device *dev) +{ + struct pm_vt_switch *tmp; + + mutex_lock(&vt_switch_mutex); + list_for_each_entry(tmp, &pm_vt_switch_list, head) { + if (tmp->dev == dev) { + list_del(&tmp->head); + break; + } + } + mutex_unlock(&vt_switch_mutex); +} + +/* + * There are three cases when a VT switch on suspend/resume are required: + * 1) no driver has indicated a requirement one way or another, so preserve + * the old behavior + * 2) console suspend is disabled, we want to see debug messages across + * suspend/resume + * 3) any registered driver indicates it needs a VT switch + * + * If none of these conditions is present, meaning we have at least one driver + * that doesn't need the switch, and none that do, we can avoid it to make + * resume look a little prettier (and suspend too, but that's usually hidden, + * e.g. when closing the lid on a laptop). + */ +static bool pm_vt_switch(void) +{ + struct pm_vt_switch *entry; + bool ret = true; + + mutex_lock(&vt_switch_mutex); + if (list_empty(&pm_vt_switch_list)) + goto out; + + if (!console_suspend_enabled) + goto out; + + list_for_each_entry(entry, &pm_vt_switch_list, head) { + if (entry->required) + goto out; + } + + ret = false; +out: + mutex_unlock(&vt_switch_mutex); + return ret; +} + int pm_prepare_console(void) { + if (!pm_vt_switch()) + return 0; + orig_fgconsole = vt_move_to_console(SUSPEND_CONSOLE, 1); if (orig_fgconsole < 0) return 1; @@ -26,6 +138,9 @@ int pm_prepare_console(void) void pm_restore_console(void) { + if (!pm_vt_switch()) + return; + if (orig_fgconsole >= 0) { vt_move_to_console(orig_fgconsole, 0); vt_kmsg_redirect(orig_kmsg);
KMS drivers can potentially restore the display configuration without userspace help. Such drivers can can call a new funciton, pm_vt_switch_required(false) if they support this feature. In that case, the PM layer won't VT switch to the suspend console at suspend time and then back to the original VT on resume, but rather leave things alone for a nicer looking suspend and resume sequence. v2: make a function so we can handle multiple drivers (Alan) v3: use a list to track device requests (Rafael) Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> --- include/linux/pm.h | 4 ++ kernel/power/console.c | 115 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 119 insertions(+)