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path: root/drivers/cpuidle/cpuidle-exynos.c
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Diffstat (limited to 'drivers/cpuidle/cpuidle-exynos.c')
-rw-r--r--drivers/cpuidle/cpuidle-exynos.c99
1 files changed, 99 insertions, 0 deletions
diff --git a/drivers/cpuidle/cpuidle-exynos.c b/drivers/cpuidle/cpuidle-exynos.c
new file mode 100644
index 000000000000..7c0151263828
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-exynos.c
@@ -0,0 +1,99 @@
+/* linux/arch/arm/mach-exynos/cpuidle.c
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/cpuidle.h>
+#include <linux/cpu_pm.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <asm/proc-fns.h>
+#include <asm/suspend.h>
+#include <asm/cpuidle.h>
+
+static void (*exynos_enter_aftr)(void);
+
+static int idle_finisher(unsigned long flags)
+{
+ exynos_enter_aftr();
+ cpu_do_idle();
+
+ return 1;
+}
+
+static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ cpu_pm_enter();
+ cpu_suspend(0, idle_finisher);
+ cpu_pm_exit();
+
+ return index;
+}
+
+static int exynos_enter_lowpower(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ int new_index = index;
+
+ /* 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)
+ return arm_cpuidle_simple_enter(dev, drv, new_index);
+ else
+ return exynos_enter_core0_aftr(dev, drv, new_index);
+}
+
+static struct cpuidle_driver exynos_idle_driver = {
+ .name = "exynos_idle",
+ .owner = THIS_MODULE,
+ .states = {
+ [0] = ARM_CPUIDLE_WFI_STATE,
+ [1] = {
+ .enter = exynos_enter_lowpower,
+ .exit_latency = 300,
+ .target_residency = 100000,
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .name = "C1",
+ .desc = "ARM power down",
+ },
+ },
+ .state_count = 2,
+ .safe_state_index = 0,
+};
+
+static int exynos_cpuidle_probe(struct platform_device *pdev)
+{
+ int ret;
+
+ exynos_enter_aftr = (void *)(pdev->dev.platform_data);
+
+ ret = cpuidle_register(&exynos_idle_driver, NULL);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register cpuidle driver\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct platform_driver exynos_cpuidle_driver = {
+ .probe = exynos_cpuidle_probe,
+ .driver = {
+ .name = "exynos_cpuidle",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_platform_driver(exynos_cpuidle_driver);