ARM: EXYNOS: cpuidle: fix AFTR mode check

The EXYNOS cpuidle driver code assumes that cpuidle core will handle
dev->state_count smaller than drv->state_count but currently this is
untrue (dev->state_count is used only for handling cpuidle state sysfs
entries and drv->state_count is used for all other cases) and will not
be fixed in the future as dev->state_count is planned to be removed.

Fix the issue by checking for the max supported idle state in AFTR
state's ->enter handler (exynos4_enter_lowpower()) and entering AFTR
mode only when cores other than CPU0 are offline.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 2 insertions, 6 deletions

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index ddbfe8709fe7..8e0eb2ef8c41 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -151,8 +151,8 @@ static int exynos4_enter_lowpower(struct cpuidle_device *dev,
 {
         int new_index = index;
 
-        /* This mode only can be entered when other core's are offline */
-        if (num_online_cpus() > 1)
+        /* AFTR can only be entered when cores other than CPU0 are offline */
+        if (num_online_cpus() > 1 || dev->cpu != 0)
                 new_index = drv->safe_state_index;
 
         if (new_index == 0)
@@ -214,10 +214,6 @@ static int exynos_cpuidle_probe(struct platform_device *pdev)
                 device = &per_cpu(exynos4_cpuidle_device, cpu_id);
                 device->cpu = cpu_id;
 
-                /* Support IDLE only */
-                if (cpu_id != 0)
-                        device->state_count = 1;
-
                 ret = cpuidle_register_device(device);
                 if (ret) {
                         dev_err(&pdev->dev, "failed to register cpuidle device\n");