On Fri, Oct 30, 2015 at 04:31:58PM +0800, Chen Yu wrote:
> From: Zhang Rui <[email protected]>
>
> Current thermal code does not handle system sleep well because
> 1. the cooling device cooling state may be changed during suspend
> 2. the previous temperature reading becomes invalid after resumed because
> it is got before system sleep
> 3. updating thermal zone device during suspending/resuming
> is wrong because some devices may have already been suspended
> or may have not been resumed.
>
> Thus, the proper way to do this is to cancel all thermal zone
> device update requirements during suspend/resume, and after all
> the devices have been resumed, reset and update every registered
> thermal zone devices.
>
> This also fixes a regression introduced by:
> Commit 19593a1fb1f6 ("ACPI / fan: convert to platform driver")
> Because, with above commit applied, all the fan devices are attached
> to the acpi_general_pm_domain, and they are turned on by the pm_domain
> automatically after resume, without the awareness of thermal core.
>
> CC: <[email protected]> #3.18+
> Reference: https://bugzilla.kernel.org/show_bug.cgi?id=78201
> Reference: https://bugzilla.kernel.org/show_bug.cgi?id=91411
> Tested-by: Manuel Krause <[email protected]>
> Tested-by: szegad <[email protected]>
> Tested-by: prash <[email protected]>
> Tested-by: amish <[email protected]>
> Tested-by: Matthias <[email protected]>
> Reviewed-by: Javi Merino <[email protected]>
> Signed-off-by: Zhang Rui <[email protected]>
> Signed-off-by: Chen Yu <[email protected]>
Acked-by: Eduardo Valentin <[email protected]>
> ---
> drivers/thermal/thermal_core.c | 42 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 42 insertions(+)
>
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index 682bc1e..9aae767 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -37,6 +37,7 @@
> #include <linux/of.h>
> #include <net/netlink.h>
> #include <net/genetlink.h>
> +#include <linux/suspend.h>
>
> #define CREATE_TRACE_POINTS
> #include <trace/events/thermal.h>
> @@ -59,6 +60,8 @@ static LIST_HEAD(thermal_governor_list);
> static DEFINE_MUTEX(thermal_list_lock);
> static DEFINE_MUTEX(thermal_governor_lock);
>
> +static atomic_t in_suspend;
> +
> static struct thermal_governor *def_governor;
>
> static struct thermal_governor *__find_governor(const char *name)
> @@ -554,6 +557,9 @@ void thermal_zone_device_update(struct thermal_zone_device *tz)
> {
> int count;
>
> + if (atomic_read(&in_suspend))
> + return;
> +
> if (!tz->ops->get_temp)
> return;
>
> @@ -2155,6 +2161,36 @@ static void thermal_unregister_governors(void)
> thermal_gov_power_allocator_unregister();
> }
>
> +static int thermal_pm_notify(struct notifier_block *nb,
> + unsigned long mode, void *_unused)
> +{
> + struct thermal_zone_device *tz;
> +
> + switch (mode) {
> + case PM_HIBERNATION_PREPARE:
> + case PM_RESTORE_PREPARE:
> + case PM_SUSPEND_PREPARE:
> + atomic_set(&in_suspend, 1);
> + break;
> + case PM_POST_HIBERNATION:
> + case PM_POST_RESTORE:
> + case PM_POST_SUSPEND:
> + atomic_set(&in_suspend, 0);
> + list_for_each_entry(tz, &thermal_tz_list, node) {
> + thermal_zone_device_reset(tz);
> + thermal_zone_device_update(tz);
> + }
> + break;
> + default:
> + break;
> + }
> + return 0;
> +}
> +
> +static struct notifier_block thermal_pm_nb = {
> + .notifier_call = thermal_pm_notify,
> +};
> +
> static int __init thermal_init(void)
> {
> int result;
> @@ -2175,6 +2211,11 @@ static int __init thermal_init(void)
> if (result)
> goto exit_netlink;
>
> + result = register_pm_notifier(&thermal_pm_nb);
> + if (result)
> + pr_warn("Thermal: Can not register suspend notifier, return %d\n",
> + result);
> +
> return 0;
>
> exit_netlink:
> @@ -2194,6 +2235,7 @@ error:
>
> static void __exit thermal_exit(void)
> {
> + unregister_pm_notifier(&thermal_pm_nb);
> of_thermal_destroy_zones();
> genetlink_exit();
> class_unregister(&thermal_class);
> --
> 1.8.4.2
>