1 files changed, 69 insertions, 0 deletions

diff --git a/drivers/cpuidle/cpuidle-at91.c b/drivers/cpuidle/cpuidle-at91.c
new file mode 100644
index 000000000000..a0774370c6bc
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-at91.c
@@ -0,0 +1,69 @@
+/*
+ * based on arch/arm/mach-kirkwood/cpuidle.c
+ *
+ * CPU idle support for AT91 SoC
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * The cpu idle uses wait-for-interrupt and RAM self refresh in order
+ * to implement two idle states -
+ * #1 wait-for-interrupt
+ * #2 wait-for-interrupt and RAM self refresh
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/cpuidle.h>
+#include <linux/io.h>
+#include <linux/export.h>
+#include <asm/proc-fns.h>
+#include <asm/cpuidle.h>
+
+#define AT91_MAX_STATES 2
+
+static void (*at91_standby)(void);
+
+/* Actual code that puts the SoC in different idle states */
+static int at91_enter_idle(struct cpuidle_device *dev,
+                        struct cpuidle_driver *drv,
+                               int index)
+{
+        at91_standby();
+        return index;
+}
+
+static struct cpuidle_driver at91_idle_driver = {
+        .name                   = "at91_idle",
+        .owner                  = THIS_MODULE,
+        .states[0]              = ARM_CPUIDLE_WFI_STATE,
+        .states[1]              = {
+                .enter                  = at91_enter_idle,
+                .exit_latency           = 10,
+                .target_residency       = 10000,
+                .flags                  = CPUIDLE_FLAG_TIME_VALID,
+                .name                   = "RAM_SR",
+                .desc                   = "WFI and DDR Self Refresh",
+        },
+        .state_count = AT91_MAX_STATES,
+};
+
+/* Initialize CPU idle by registering the idle states */
+static int at91_cpuidle_probe(struct platform_device *dev)
+{
+        at91_standby = (void *)(dev->dev.platform_data);
+        
+        return cpuidle_register(&at91_idle_driver, NULL);
+}
+
+static struct platform_driver at91_cpuidle_driver = {
+        .driver = {
+                .name = "cpuidle-at91",
+                .owner = THIS_MODULE,
+        },
+        .probe = at91_cpuidle_probe,
+};
+
+module_platform_driver(at91_cpuidle_driver);